11# EOT Crane Operation Manual

Operation Manual for Overhead Crane

1

2

Electrical Equipment

3 Crane Travel

Trolley

Mechanism

4

5

Bridge

Hook

1.6.2 Trolley Trolley is composed of frame, main hoisting mechanism, aux. hoisting mechanism and traversing mechanism (see Fig 3). The frame of trolley is the steel structural member that is made of the box girder and I-shaped beam by welding..

Fig 3 1 frame

Trolley

2

3

4

aux.hoisting

main hoisting

trolley traverse

mechanism

mechanism

mechanism

1.6.2.1 Hoisting Mechanism 5


Hoisting mechanism (Fig 3) comprises motor, brake, reducer, drum, crown sheave sets,limit device, wire rope and hook lifting beam (hoist horizontal beam) etc. The arrangement of hoist mechanism (drums upright to main girder) is located on the crane; please find details in Fig 2. 1.6.2.1.1 Operation Principle of Hoisting Mechanism The operation principle of hoisting mechanism: After power-on, all brakes will be released at the same time. The motor will drive the reducer, which drives the drum to rotate and make its wire rope lower or lift drive the hook (or grab or magnetic chuck) to lower and lift, along which the handled material is lifted or lowered. The hoisting mechanism is equipped with limit switches (weight-type or rotating-type) for lifting limiting position. They can guarantee to cut off the power supply to motor when the hook is lifted to the specified design limiting position. 1.6.2.1.2 Main Components of Hoisting Mechanism: ——Reducer

The horizontal reducer used in the hoisting mechanism is one with hardened tooth-surface and welded housing made by DHI.DCW ----Drum Assembly The drum is made of Q345-B steel plate by rolling and of welded minor axis type barrel structure. After rolling, it will be welded by a special automatic welding machine, and stress relieved and annealed after welding. Finally the nondestructive test is conducted for the drum. See Fig 4.

Fig 4 Sketch of Drum There are two steel core wire ropes which are fixed on clip of each drum. (Fig 5.)

Fig 5

Assembly of Wire Rope

---- Wire Rope 6


For the common safety factors of wire rope for general-purpose overhead traveling crane (FEM), see Table 3 Table 3 Safety Factor of Wire Rope for Crane Group Classification of Mechanism

Safety Factor

M6

5.6

M7

7.1

The remaining safety wraps of wire rope on the drum (exluding the wraps of wire rope which are used for fixing the rope end) should be not be less than 2 wraps. ——Safety Devices

The hoisting mechanism is equipped with double limit switches (weight-type and rotating-type) for lifting limiting position. For the specific operation principle, see 《ChapterII Safety 》. ——Motor and Overspeed Switch 。（Its performance see The hoisting mechanism of Crane generally use ：YZR or YZP series motor 。（《Chapter Six Component》）

In the case where no special requirements are specified, the power marked on the nameplate of motor is the reference duty of motor, i.e. S3, that is the power when the reference cyclic duration factor is 40%. The overspeed switch (LY1 type) is installed on the tail of motor axle and used to limit the overspeed of motor so as to ensure the safety in operation. (The overspeed switch had been adjusted when it leaved the factory, so it will not be not adjusted casually. The switch main axle should be periodically checked, cleaned and lubricated at yearly intervals.) Weight-type Limit Switch The weight-type limit switch is the second protective device for hoisting range limitation. The switch is installed on the trolley frame. The weight is installed on the sheave cover frame of lifting beam of laminated hook. The cover on the

weight is covered on the hoisting wire rope. When hook lifting

beam is lifted l ifted up to the upper limiting position, the rope that supports the weight will lose the tension and the limit switch reset, and the the power supply is cut off and the trolley stopped. —— Electro-Hydraulic Drum Brakes

The hoisting mechanism of Crane generally use ：Electro-Hydraulic Drum Brakes. Operation principle see 《ChapterII Safety 》. ——Hook Sets（Fig 6）

Hook sets is consisted of hook, hook horizontal beam, hook nut, rolling sheave and yoke plate.

7


Fig 6

Hook sets

1.6.2.2 Trolley Traverse Mechanism （Fig 7） Trolley traverse mechanism is consisted of Wheel, Moment support and SEW three-in-one motor reducer and wheels. Operation principle of traversing mechanism ： The main trolley traversing mechanism has two drives, aech of which will drive one driving wheel on one of the two rails separately (also called separate drive).After power-on, the brake will be released. Then the motor will be rotated to drive the wheel to run forward via gearbox. When the motor is rotated in the reverse direction, the wheel will be driven to run backward.

Fig 7 Traverse Mechanism of Trolley No.

1

Description

Wheel

2 Moment support

8

3 SEW Three-in-one Motor with reducer


1.6.3 Crane Traveling Traveling Mechanism （Fig 8） The crane traveling mechanism is composed of four drives and wheels. Each of the drives includes the following main components, i.e. motor, brake and reducer. reducer. After power-on, the brakes will be released and the motors will be rotated to drive wheels run leftward and rightward via reducer. When motor is rotated in the reverse direction, the wheels will run leftward and rightward.

Fig 8 Sketch of Crane Traveling Mechanism

No.

1

2

Description

Wheel

Coupling

3 Drive shaft

4

5

6

7

Reducer

Motor

Brake

Buffer

1.6.4 Bridge （Fig 9） The bridge refers to the load-carrying steel structure of crane (also called metal structure). The bridge is composed of two main girders and two end carriages. Two rails are installed on the two main girders respectively, the main girders and end carriages are of welded box girder structure, which has enough strength and stiffness and stability. The main girders are bias-rail box girders (the rail is installed on T-shaped steel of main web plate, as shown in Fig 10). The passage is provided on the outside of main girder. The stairway is provided from the passage below to the passage above. Rigid end carriage: the main girders and end carriages of bridge are connected using high strength bolts.

9


Fig 9

Bridge

Fig 10 Bias-Rail Box Girder

10


Chapter II

Safety

Table of Contents 2.1 General Rules for Safety .........................................................................................................................12 2.2 Safety Symbol .........................................................................................................................................12 2.3 Safety and Protection Device ...................................................................................................................15 2.4 Failure Disposal Method .........................................................................................................................21 2.5 Measures Taken to Prevent Unqualified Personnel from Operating Overhead Traveling Crane ................21 2.6 Other Safety Precautions and Measures ...................................................................................................21

11


Safety 2.1 General Rules for Safety In order to ensure the safety in operation of crane, “Safety Rules for Lifting Appliances” (GB 6067) must be obeyed and special attention must be paid to the following safety items. 2.1.1 The daily inspection and maintenance of crane should be stayed. In order to make sure that the crane could be normally operated in a good state, the mechanical movement of crane, wearing condition of all components and lubrication situation must be inspected regularly according to the maintenance list. If there is any problem to be found during daily inspection, you must take action immediately to repair properly and make the crane be operated in the optimal working condition. 2.1.2 The safety and protection devices that are installed on every location must be checked for intactness, correct movement, tight connection and function meeting the requirements. It is not allowed to disassemble any device casually. 2.1.3 In order to keep the crane operating normally in the optimal condition, the structure and movement principle must be understood and mastered. 2.1.4 In order to ensure the safety in production, the operator and maintenance personnel must know well the meaning of all safety signals and make correct reaction to them in time. 2.1.5 Please bear in mind that: I will not hurt myself. I will not hurt other people. I will not be hurt by other people. 2.2 Safety Symbol The safety symbols are important facilities which are used to remind the operator and maintenance personnel of possible danger and potential danger and help them to recognize danger and avoid danger. According to the requirements as specified in GB2894－1996, the safety symbols must be put up or hung on the crane. See Table 4. Table 4

Safety Symbol and Installation Location of Crane

Symbol

Description

Installation Location

Prohibition Symbol No Switching-in

It is hung on the main

It means that the equipment is under power failure and someone is doing maintenance.

switch

in

the

electrical

room or driver’s cabin

If you do not obey it, personal damage would happen and life would be endangered and damage done to equipment if serious. No Stacking

It is hung on the place

It means that this crane is required to operate

to

and fro in this area.

close to the rail face of main and auxiliary trolleys

If you do not obey it, equipment would be

and or runway rails as well

damaged and damage to equipment would be

as the surface of upper

endangered if serious.

platform of main girder and auxiliary girder.

12


Symbol

Description Keeping away

Installation Location It is hung on at the side of

It indicates that the rotating mechanical parts exist in this area and can not be closed in.

the rotating components of drive

If you do not obey it, personal damage would happen and the life would be endangered if serious. No Throwing about It indicates that throwing anything downward

It is hung on the platform

is forbidden. If you do not obet it, personal damage would happen and the life would be endangered if serious. Warning Sign Take Care Not to Get An Electric Shock

It is hung on the side of

It means that this live or leak place or article is power likely to exist.

supply

wiring,

electrical room, HV room

If you do not obet this warning, you would get an electric shock or the equipment would be shorted out and damage done to people. The life would be endanger and damage done to equipment if serious. Beware of Falling

It is hung on the edge of

It means that falling likely to happen here.

each

platform,

If you do not obey it or not pay attention to it,

guardrail

falling down likely to happen from platform, passage guardrail and high altitude platform. The life would

and when

near

the

atairway doing

maintenance.

be endanger if serious.. Beware of Suspended Load It means that there is a suspended load is being moved over your head you must keep away from it.

It is hung on at site of erection and commissioning

If you do not obey it, damage would be done to people. The life would be endanger if serious. Take Care Not to Be Injured by Machine It means that somebody is likely to be injured while the crane is running.

It

is

people. The life would be endanger if serious.

13

on

in

the

commissioning area on the crane

If you do not obey it, damage would be done to

hung


Symbol

Description

Installation Location

Warning!

It is hung on at the doorway

It prompts the unqualified person not get out of of line.

electrical

room

and

driver’s cabin

If you do not obey it. equipment damage and human casualty accident are likely to happen during installation,

commissioning,

operation

and

maintenance of equipment. Danger!

It

is

hung

on

in

the

in

the

It prompts the people concerned to avoid danger maintenance area at this area. If you do not obey it, serious equipment damage and human casualty accident are likely to happen during installation, commissioning, operation and maintenance of equipment. Caution!

It

It prompts the people concerned that potential danger likely to exist in this area.

is

hung

on

commissioning

and

maintenance areas.

If you do not obey it, serious equipment damage and human casualty accident are likely to happen during installation, commissioning, operation and maintenance of equipment Instruction Sign Fasten Safety Belt!

It

If you do not obey it, danger of falling down from high altitude and the life safety would be

is

hung

on

in

commissioning

the and

maintenance areas.

endangered if serious.

Wear Safety Helmet!

It

It indicates that the head or other parts of body are in danger of being bruised or scored by falling

is

hung

on

in

commissioning

the and

maintenance areas.

articles from high altitude and edges and corners of equipment. If you do not obey it, you would be bruised and the life safety would be endangered if serious. Wear Protective Suit!.

It

If you do not obey it, you would be scored by edge angle and the life safety would be endangered if serious.

14

is

hung

on

commissioning maintenance areas.

in

the and


Symbol

Description Wear Protective Gloves!

Installation Location It

If you do not obey it, you would be scored by edge angle and the life safety would be endangered

is

hung

on

in

commissioning

the and

maintenance areas.

if serious.

Wear Protective Shoes!

It

It you do not obey it, you would get an electric

is

hung

on

in

the

commissioning area.

shock, thus resulting in personal injury when working in the live or leak place. The life would be endangered and equipment damage would happen if serious. Be Locked!

The door of driver’s cabin

If you do not obey it, equipment damage and

is locked up (when nobody

personal injury would happen. The life safety would

takes spells and the crane is

be endangered if serious.

parked)

Stop! Dangerous High Voltage

It is hung on in front of the

Reminding Sign

It prompts the people concerned not to go ahead

high voltage room

in front of the high voltage area. If you do not obey it, he would get an electric shock, thus resulting in bodily injury. The life and equipment would be endanger and equipment damage would happen if serious. During erection and commissioning of overhead traveling crane, the user and company in charge of installation and commissioning must hang the legible and readable danger warning sign in the dangerous area of equipment. Erection company or user must take responsibility to purchase and hang the safety sign. 2.3 Safety and Protection Devices The safety and protection devices are the devices essential to prevent the overhead trsveling crane from accident. They include the devices that limit the travel distance and operation position and the devices that prevent the crane from overloading, the interlock protection devices etc. The overhead traveling crane is provided with the following: 2.3.1 Safety Devices to Limit Travel Distance and Operation Position The hoisting mechanism is provided with rotating-type limit switch and weight-type limit switch for hoisting travel to ensure safety and reliability in operation. When the lifting implement is lifted up to the specified upper limiting position, both switches can cut off the power supply to the hoisting mechanism and 15


when it is lowered to the limiting position, both switches can automatically cut off the power supply for lowering motion so as to ensure that the wraps of wire rope wound on the drum are not less than two wraps specified in the design documents. After cutting off the power supply to the movement in the above-mentioned direction for motor, the power supply to the movement in the opposite direction is still reserved. At this time the mechanism can move in the opposite direction. (1) Llimit switch for hoisting Travel The rotating-type limit switch is mounted on the minor axis at the tail of drum and rotated synchronously together with the drum. It is used to collect the parameter of rotating wraps of the drum to controlthe upper and lower limits of hoisting mechanism. (Fig 11)

Fig 11 Sketch of Rotating-type Limit Switch For the weight-type limit switch (Fig 12) , its switch is installed on the trolley frame and the weight is installed on the support of sheave hood of the hook and the sleeve of weight i s hollowed the hoisting wire rope (Fig 13). When the hook is lifted up to the upper limit, the wire rope that supports the weight will lose the tension, the limit switch will be reset, the power supply is cut off and the mechanism will be stopped.

Fig 12 Weigh-type Limit Switch

16


Fig 13 Installation Sketch of Weight-type Limit Switch (2) For the travel distance limit switch, the limit switch and collision head are installed on the main girder. (Fig 14)

Fig 14 Sketch of Installation of Travel Distance Limit Switch The traveling mechanism, main traversing and auxiliary traversing mechanisms are provided with the travel distance limit switches in each of movement directions of crane. When the crane, or main trolley or auxiliary trolley reaches the specified design limiting position, the fixed striker plates will actuate the switch and cut off the power supply the movement in forward direction. Where the traveling (traversing) speed is higher (more than 100 m/min) or the requirements for parking location are stricter, the traveling mechanism, main traversing and auxiliary traversing mechanisms are provided with the traveling distance limit switches at two levels on user’s demand. The limit switch at the first level will send out a reduced speed signal and reduce the speed as specified, and the limit switch at the second level will automatically cut off the power supply and stop the crane (trolley). 2.3.2 Safety Device for Prevention of Overload The safety device for prevention of overload mainly refers to the lifting load limiter. The lifting load limiter that is provided for the hoisting mechanism is the safety device which is used to prevent the crane from leading to damage to and failure of the structure and mechanism due to overload. The lifting load limiter for the hoisting mechanism is installed at the bearing block of drum. (Fig15)

17


Fig 15 Sketch of Installation of Sensor When the actual lifting capacity exceeds 95% of the rated lifting capacity, the lifting capacity limiter will send out an alarm signal. When the actual lifting capacity is 100% ~ 110% of the rated lifting capacity, the lifting capacity limiter will be actuated and at this time the power supply should be cut off automatically. However, the load is only allowed to be lowered to the ground. The electronic scale is also provided with the lifting load limiter. 2.3.3 Buffer and End Stop Block (Fig 16) The crane traveling mechanism and trolley traversing mechanisms are all provided with buffers. The buffers have the good performance to absorb the energy of travel mechanisms and reduce the impact. The collision heads and stopping blocks at the ends of both rails are fixed securely and reliably. The stop blocks at the ends of both rails have the performance to prevent the crane from derailing.

Fig 16 Installation of Buffer 2.3.4 Safety Devices that Play Interlocking and Protection Role The door access to the crane and the door through which the personnel get access to the bridge platform from the operator’s cab are all provided with the interlocking switches (Fig. 17). When the door is opened, the power supply to all the mechanisms will be cut off.

Fig 17 Installation Sketch for Interlocking Switch 18


2.3.5 Protective Hood The sheaves are provided with the protective hood (Fig. 18) to prevent the wire rope from leaving out of the groove.

Fig 18 Sheave Hood The protective devices are provided at the parts and components which are likely to lead to danger the personnel from operation of the mechanism. The moving components such as coupling and transmission shaft that are exposed and likely to hurt the personnel are provided with the protective hoods and guardrail. The warning sign is sticked on each of the protective hoods.

(Fig 19)

Fig 19 Protective Hood 2.3.6 Protection against Electric Shock

(Fig 20)

The operator’s cabin of overhead traveling crane is located on one side of runway sliding contact contactor where danger of electric shock exists. The guard net for isolation is provided between the ladder and footwalk access to the crane and the sliding contact conductors in the relative area. The warning sign board is hung on the guard net.

Fig 20 Isolation Net for Protection against Electric Shock The guard frame is provided on the side of sliding contact conductor of the crane (Fig. 21) to prevent the 19


lifting implement or wire rope from making accidental contact with the sliding contact conductor due to swaying when the trolley is located at the end limiting position. The warning sign board is sticked on the end carriage.

Fig 21 Guard Frame of Runway Conductor 2.3.7 Protection against Falling The safe and reliable maintenance cage (Fig22) or platform is installed at the end of bridge for the maintenance personnel who stand and work in or on it during inspection and repair of crane. The exposed connection bolts after installation will be spot welded to prevent them from loosening and falling.

Fig 22 Maintenance Cage & Warning Signs to Be Hung on

2.3.8 Rail Sweeper The rail sweepers are installed in the front of wheels of the crane and main and auxiliary trolleys. The clearance between the bottom of cleaning plate and the top of rail is 10 mm. The rail sweepers will be used to clean the material accumulated on rails, which becomes a clog of operation. The sing of “No Stacking“ is put on at the side of rail. See Fig 23.

Fig 23 Rail Sweeper & Warning Signs 2.3.9 Alarming Device 20


The crane is provided with alarming devices for operation such as buzzer and flashlight. 2.4 Disposal Method in case of Failure When any failure occurs, it must be informed to the chief officer and repaired in time. It is required to hang the warning sign. The driver is not allowed to leave the operating post and must warn anyone not to go through the dangerous area.

Danger

Caution

Warning

2.4.1 Disposal Method in Case of Failure Occurring in HoistIng Mechanism ---- The main hoisting mechanism is provided with brake, lifting limit switch and overload protective device. ---- If there is any abnormal sound to be heard during operation of crane, the trolley must be stopped immediately and the power supply is cut off to check. The lifted load should be put down at low speed. ---- When power failure occurs suddenly or the line voltage drop exceeds the specified value during operation of crane, The lifted load should be put down at low speed. All controllers should turned back to zero position as soon as possible, the master switch is cut off and it should be informed to the commaander. It is required to hang the warning sign. The driver is not allowed to leave the operating post and must warn anyone not to go through the dangerous area. 2.4.2 Disposal Method in Case of Failure Occurring in Travel Mechanisms When a motor or a brake is damaged during operation of crane traveling and trolley traversing mechanisms, the crane or trolley should be stopped for repair. 2.5 Measures Taken to Prevent Unqualified Personnel from Operating Overhead Traveling Crane The crane driver and matainence personnel must work with qualification certificate. The key of operator’s cabin door can only be kept by the driver and assigner of user. 2.6 Other Safety Precautions and Measures For the precautions to be taken before, during and after operation of crane, see Chapter IV “Operation”. For the safety precautions to be taken during matainence and commisioning of crane, see the relevant chapters.

21


Chapter III Erection and Adjustment (or Commissioning) Table of Contents 3.1 Preparation before Erection...........................................................................................................................23 3.2 Erection and Adjustment of Hoisting Mechanism ........................................................................................23 3.3 Installation Precision Among Each Components.......................................................................................... 24 3.4 Installation and Adjustment of Long Traveling and Trolley Traverse Mechanism ......................................25 3.5 Installation and Adjustment of Bridge and Connection of High Strength Bolting........................................26 3.6 Test and Inspection Procedure.......................................................................................................................33

22


Erection & Adjustment (or Commissioning) 3.1 Preparation before Erection The erection and commissioning of crane must be carried out by the qualified erection company according to the drawings and this instrucation manual provided by the manufacturer. Before erection, the following requirements must be met: 3.1.1 Unpack the packing box and check the amount of components and documents and materials as per packing list. At the same time, the appearance check must be carried out. 3.1.2 Read the additional Drawings of Erection and instrucation manual provided by the manufacturer and prepare the erection plan and procedure according to the real objects. 3.1.3 Remove the deviations and defects that caused by transportation or improper storage according to the technical requirements on the drawings. 3.1.4 When the crane has been stored for a long time (more than half a year), it should be checked for corrosion and recoated with paint if necessary. 3.1.5 The erectors must receive the safety education for the specific procedure and have passed the examination. 3.1.6 The erection company must carry out the thorough check of lifting equipment so as to ensure the safety during erection. 3.1.7 The erection company should hang or place the safety warning sign boards at thesite of erection. 3.2 Erection and Adjustment of Hoisting Mechanism The hoist mechanism has been well assembled in the manufacturer’s workshop and passed the no-load test. The components such as drum assembly, fixed sheave block, motor etc. which are disassembled due to out-of-gauge during transportation and the accessories such as platform etc should be installed on the trolley frame according to the position and technical requirements as specified on the drawings after the trolley frame has been assembled and adjusted. 3.2.1 One end of the drum is supported on the output shaft of reducer by the drum coupling. The other end is supported on the base of drum. It should be checked if the drum coupling bolts are loosened, the gap is left between both ends of bearing on the drum base and the bolts at the end of output shaft of reducer are tightened up before erection. 3.2.2 For the motors that placed for a long time, the insulation resistance between the stator and rotor winding and the enclosure ot the shaft must be measured using a 500V megger before installation. If the resistance is lower than 0.5 MΩ, the motor must be dried and the temperature of winding cannot exceed 145℃ when drying. The inside of motor should be blowed and cleaned by dry compressed air. The mechanical check should be carried out to see if the fasteners are loose, the rotor can be rotated flexibly when it is turned by hand and the shaft head nuts of coupling mounted on the tapered shaft extension are tightened up. The motor must be rotated with no load for 30 to 40 minutes. When the motor is energized, the rotating direction must be confirmed and then the installation will be performed after the correct direction has been confirmed in order to avoid the machine parts from being damaged due to reversed polarity. When installation, the relative position between the central line of motor and that of high speed shaft of reducer must be corrected (For the allowable deviation, see Clause 3.3). The holding down bolts should be tightened up after adjustment.

23


3.2.3 Check whether the sensor for fixed sheave block is assembed tightly and the connection is intact. 3.2.4 Check Assembly Position of Brake The axiality between the central line of brake and the axis of brake wheel: when the diameter of brake wheel D<315mm, the axiality is 2 mm and when D≥315 mm, the axiality is 3 mm. Adjust the gap between the brake wheel and the brake spacer (see Clause 3.3), and their contact area

≮70%. Rotate the brake wheel by hand to make the drum rotate one turn without seizure. All joints and hinges should be rotated flexibly without seizure and twisting. Adjust the springs of four brakes to make the braking torques be identical. 3.2.5 After the main trolley is lifted an erected onto the bridge, the wire rope will be installed. The drum with left hand groove will use the right-hand lay wire rope, and the drum with right hand groove will use left-hand lay wire rope. The end of wire rope is fixed on the drum by clip and two safety wraps of wire rope remain on the drum. The other end of each wire rope will be reeved around the sheave on the lifting beam (be hollwed by the weight of weight-type limit switch at the same time) and the fixrd sheave on the trolley frame according to the wire rope reeving diagram and then fixed by wedge sleeve and clamped by rope clip. When the wire rope is fixed, the balance position of lifting cross bar )lifting beam) on the hook will be adjusted to the horizontal position, and the error is not more than 2L/1000 (where L is the central distance of two hooks). The working face of mouth of two hooks should kept horizontal. 3.2.6 The limit switch is so installed and adjusted that it should comply with the requirements for the limiting position. 3.2.7 After all the mechanisms have been installed, the installation precision between the exes of components and that of the brake wheel should comply with the requirements in the related clauses (e.g. Clause 3.3). special attention must be paid to t he double teeth coupling, which is tested strictly. 3.2.8 Install and check the lubrication system of hoisting mechanism: each coupling should be fully filled with grease. The reducer should be filled with oil according to the requirements on the drawings. The oil pumps should be installed in place. The oil inlet pipelines of fixed sheave block and drum assembly should intact without deformation. The lubrication device of wire rope should be installed tightly and be full of oil. 3.2.9 The installation and adjustment of each of the components should be performed according to the instructions for components provided by the suppliers. 3.3 Installation Precision between Components The installation precision between the components is determined according to the types of connected couplings. 3.3.1 The offset angle

α

between the axes of two components (Fig 24) doesnot exceed 1.5° for the gear

couplings, and doesnot exceed 10° ～15° for the universal couplings.

Fig 24 Offset Angle and Radial Displacement of Coupling

24


3.3.2 When no deviation between the axes of two components exists, see Table 5 for the allowable radial displacement of gear coupling. Table 5 Allowable Deviation of Installation of Coupling (mm) 10

3 Type

4 Type

5 Type

6 Type

7 Type

8 Type

9 Type

Modulus m

3

3

3

4

4

4

6

6

Number of Teeth Z

40

48

56

48

56

62

46

56

Outer Diameter of Gear D

126

150

174

200

232

256

288

348

Displacement Quantity △y

1.6

1.2

1.4

1.4

1.5

1.7

1.8

2.0

Type

3.3.3 The amplitude of swing (or jump) after installing brake wheel cannot exceed the regulation of Table 6. Table 6 Allowable Jumping Tolerance for Braking Wheel Installation (mm) Diameter of Brake Wheel

≤250

＞250～500

＞500～800

Radial Runout

0.2

0.25

0.30

Axial Swing Motion

0.15

0.20

0.25

3.3.4 The initial gap between the brake and the brake wheel is as shown in Table 7. Table 7 Initial Clearance between Brake and Brake Wheel (mm) Diameter of Brake Wheel D

250

315

400

500

630

710

800

Initial Clearance between

1.25

1.25

1.25

1.25

1.6

1.6

1.6

Brake Lining and Brake Wheel 3.4 Installation and Adjustment of Traveling and Traversing Mechanisms The traveling and traversing mechanisms have been well assembled in the manufacturer’s workshop and passed through no-load test. When it is necessary to reassemble them due to disassembly and maintenance for transportation, the following requirements should be met: 3.4.1 The allowance of the span of crane is ±5 ～±8 mm (when the span S ≤28 m, it is ±5 mm; when S＞28 m, it is ±8 mm). The relative error of span measured from each pair of wheels does not exceed 5 mm. The trolley gauge measured from the trolley wheel is ±3 mm and the relative error does not exceed 3 mm. 3.4.2 The horizontal skew of each wheel end face: when there are four wheels, the wheel skew

△P=│P1-P2│≤m/1200, and the skew direction of two wheels which are in the same axes has the opposite direction. When there are more than four wheels, two wheels under each equalizing bogie (equalizing beam)

△P=│P1-P2│≤m/1200, but the skew between all wheels under the same end carriage does not exceed m/800 and it is allowed not to control the skew direction of wheel. The unparallel direction of two opposite driving wheels (or driven wheels) should be opposite. See Fig 25. 3.4.3 The vertical skew of wheel tread does not exceed D/400, and the upper part must skew to the outside of rail. 3.4.4 The parity error for two wheels that installed on the same equalizing beam does not exceed 1 mm. The maximum value of parity error for wheels under same end carriage: when there are two wheels, it does not 25


exceed 2 mm. When there are more than two wheels, it does not exceed 3 mm. See Fig 26. 3.4.5 The wheel is suspended under no load and rotated one t urn by hand without seizure. 3.4.6 All the wheels should make contact with the rail under no load.

Fig 25 Horizontal Skew

m m 3 ≤

m m 1 ≤ Fig 26 Parity Error

3.4.7 Adjust the amount of compression of spring for two brakes (four brakes) to make braking torques keep consistent. 3.4.8 Adjust the limit switch so that t he trolley can be correctly stopped at the limiting position. 3.4.9 When the backing plate and the base for each component are aligned, the unmachined faces are allowed to add the spacers but not add more than two layers of spacer (three layers are allowed at the wheel). After installation, they must be welded on the underframe ahd the weld where the spacers are added should be relatively enlarged to ensure the weld being firm without loosening in operation. 3.5 Installation and Adjustment of Bridge and Connection of High Strength Bolting The bridge of crane has been pre-assembled in the manufacturer’s workshop and passed the quality inspection. But for the reason that the bridge passed through the transportation and the process of disassembly, lifting, loading and storage, the bridge that arrived at the customer’s site is not integrated one, so it must be assembled and adjusted at the customer’s site. When the bridge is lifted and erected, it should be done by use of the lifting ears on the cover plate of main girder (trolley frame). The included angle of lifting wire rope to the horizon should be ≮70° (otherwise damage to the lifting ear will lead to serious consequence). Keep the center of gravity in central position. See Fig 27. When the main girder (trolley frame) is lifted, other heavy loads should not be put on it so as to avoid the accident.

26


Fig 27 Sketch of Lifting and Erection of Main Girder 3.5.1 Installation Method of End Carriage Joint Put the bridge in sections on the level and parallel rails. The main girders and end carriages are connected according to the labeled graph of joint position and the bolt holes of main girders and end carriages. The connection should be done as specified in 3.5.2. 3.5.2 High Strength Bolting The steel structure of crane is connected by use of high strength bolts which load is transferred by frictional force. The high strength bolting has the characteristics of low stress concentration, good rigidity, more uniform force transfer and high load-carrying capacity. In order to guarantee the load transfer, the friction face of connected joints had been specially treated by sand blasting and coated with paint and reached the high roughness and skid resistance factor. When on-site erection, the special torque spanner wrenches accompanied with the crane are used at the site and proceed as per following steps: 3.5.2.1 The torque spanner wrench must be calibrated before use and they can only be used after calibration. Torque = arm of force ×gravity 3.5.2.2 The joint friction face should be cleaned and the uneven plates should be assembled after they meet the requirements. The friction face cannot have flap edges, burrs, weld splashings, welding scars, iron oxide scales, dirt and unnecessary painting and sludge. Around the hole, there should not be burrs. The friction faces that are ready for installation should be cleaned using the wire brush. The brushing direction should be vertical to friction stress direction. 3.5.2.3 The high strength bolting end plates should be tightly jointed each other. The gap between the contact surfaces due to tolerance on plate thickness and manufacture deviation or installation deviation should be treated as specified in Table 8 Table 8 Treatment Method for Clearance of Joint Plate No. 1

Sketch

Description When t<1.0mm, it should not be treated

27


When t=1.0～3.0 mm, one side of thick plate is ground to

2

1:10 gentle slope so that the gap is less than 1.0 mm When t＞3.0 mm, the backing plate should be added. The thickness of backing plate is not less than 3 mm and not

3

more than three layers at maximum. The material of backing plate and the treatment method for friction face should be identical to those of the members. The gap is controlled according to the requirements as specified in the table above so that it can ensure

the structural members uniformly transfer the force after jointing. 3.5.2.4 Where there is any problem of installation hole, the oxygen acetylene cannot be used to enlarge the hole, and the punch cannot be used to correct the hole position while the high strength bolt is inserted. When the displacement is long, the reamer should be used to expand the hole. When the displacement of a certain hole position is long, the hole should be drilled once again after repair welding. The burrs around the hole should be cleaned once again after expanding the hole. 3.5.2.5 When the structural members are assembled, the temporary bolts (or rush pins) should be installed firstly. The temporary bolts cannot be useed instead of high strength bolts. The number of temporary bolts should occupy 1/3 of the connecting plate hole s ets and can not be less than 2. When some holes are out of square and the displacement is short, the drift bolt is used to punch for position fixing and then the bolt is installed. When installation bolt reach 30%, they should be tightened and fixed. 3.5.2.6 Installation of High Strength Bolt ----High strength bolts should be inserted into the holes freely and they being punched into the holes by hammer is forbidden. ----The insertion directions of high strength bolts should be consistent except part of bolts is obstructed by the structure. ----The high strength bolts cannot be installed in a rainy day. ----The positions of washers for high strength bolts should be consistent and attention should be paid to the front and back faces of washer when installation. -----The high strength bolt in the hole to be verified cannot be subjected to shear force and should be tightened up in time. 3.5.2.7 Fastening of High Strength Bolt After big hex head high strength bolts have been all installed in place, they begin to be tightened. The fastening method is generally divided into two steps, i.e. preliminary tightening and final tightening. All the high strength bolts should be preliminarily tightened. The preliminary tightening torque is 60% to 80% of the standard value. The specific torque is based on the thickness of steel plate and distance between bolts etc. If the steel plate is too thick and the bolts are arranged at greater intervals, it had better to have bigger axial force of preliminary tightening. The sequence of preliminary tightening should be in accord with that of tightening of big hex head high strength bolt, and it should be generall done from the position where the joints have high stiffness to the unconstrained free end, or from the center of group of bolts to the direction of diffusion around. This is because when the connecting steel plate is not fixed firmly due to buckling, the splice plate may be 28


swelled in the middle and can not jointed tightly if fastening from both ends to center, thus losing the effect of part of friction force transfer. The big hex head high strength bolts should be marked to prevent them from being not tightened when preliminary tightening. One kind of color is generally used for marking after preliminary tightening and another kind of color is used for marking after final tightening in order to distinguish between them. See Fig 28.

Fig 28 Fastening of High Strength Bolt In order to prevent high strength bolts from being influenced by the external environment, thus resulting in change of the torque coefficient, the preliminary tightening and final tightening should be finished at the same day. Since the insertion directions of several big hex head high strength bolts can not be consistent due to structure, the torque is only allowed to be applies on the nut and not on the bolt when the bolt is tightened in order to prevent the torque coefficient from being changed. 3.5.2.8 Inspection and Acceptance ----The high strength bolts are generally checked by knocking with 0.3kg small hammer and preveted from being not tightened. -----The torque is checked by sampling 10% of the number of bolts at each nodal point, but not less than one. A line should be scored on the end face of bolt and the nut before inspection, and the nut is unscrewed about 60° and then tightened again with torque spanner to make two lines coincide. The torque measured at this time should be within the range of allowable values listed in table 9. -----According to the actually measured torque coefficient (the torque coefficient in the inspection record) of high strength bolt, the final tightening torque for construction csn be obtained by adjusting the actually measured torque coefficient. The construction torque of big hex head high strength bolt pair for steel structural connection should be obtained by calculating the actually measured torque coefficient. Calculation formula: (GB50017-2003) N

＝

1.1

×

f

×

Py ×

M

where N ------ final tightening torque value (Nm) f ------ torque coefficient Py ------- pretension value of bolt (KN) M ------ nominal diameter of bolt (mm)

29


If it is found out that any value is out of accord with the requirements, additional 10% should be checked. If it is still unsatisfactory, the high strength bolts at the whole nodal point should be tightened again. The torque inspection of bolts should be done within 1 h after the final tightening and finished 24h before the final tightening. The values listed in Table 9 are the reference values of allowable torque. Table 9 Torque Reference Values of Torque Spanner

Model

Diameter

of Bolt

of Bolt

Performance Degree

Pretension

mm M16 M20 M22 M24 M27 M30

kN

Spanner Torque

Torque

Coefficient

Torque Coefficient

Nm

Spanner Torque

Allowable Torque Reference Value of Torque Spanner

Nm

Nm ＞154.88－211.20

16

8.8 degree

80

0.11

154.88

0.15

211.2

16

10.9 degree

100

0.11

193.6

0.15

264

20

8.8 degree

125

0.11

302.5

0.15

412.5

＞302.50－412.50

20

10.9 degree

155

0.11

375.1

0.15

511.5

＞375.10－511.50

22

8.8 degree

155

0.11

412.61

0.15

562.65

＞412.61－562.65

22

10.9 degree

190

0.11

505.78

0.15

689.7

＞505.78－689.70

24

8.8 degree

180

0.11

522.72

0.15

712.8

＞522.72－712.80

24

10.9 degree

225

0.11

653.4

0.15

891

＞653.40－891.00

27

8.8 degree

230

0.11

751.41

0.15

1024.65

＞751.41－1024.65

27

10.9 degree

290

0.11

947.43

0.15

1291.95

＞947.43－1291.95

30

8.8 degree

285

0.11

1034.55

0.15

1410.75

＞1034.5－1410.75

30

10.9 degree

355

0.11

1288.65

0.15

1757.25

＞1288.6－1757.25

＞193.60－264

---- Check the gap between connection plates by feeler gauge. When the gap exceeds 1mm, it must be adjusted again. ---- Check whether the insertion directions of big hex head high strength bolts are consistent and the front and back faces of washer is correct. ---- The skid resistance factor of joint face for high strength bolt must comply with the design requirements. Check the skid resistance factor inspection record supplied by the structural member fabricator, and the skid resistance factor re-inspection record at the job site and the torque factor re-inspection record. The bolts used for re-inspection should be checked by random sampling from the bolts in the same batch that are ready for installation at the job site and 8 sets of connecting bolt pair should be reinspected by sampling from the bolts in each batch. 3.5.2.9 Quality Record

① Certification of high strength big hex head bolt sets issued before leaving the factory ② Re-inspection certification of high strength big hex head bolt sets ③ Values of the preliminary tightening and final tightening of high strength bolts ④ Inspection record of torque spanners used at the jobsite ⑤ Inspection and acceptance records of construction quality 3.5.3 Installation of other accessories according to requirements on drawing 3.5.4 Quality Requirements for Welds during Installation 30


Welders should have qualified certificates. The welds connecting the main load-carrying structures during installation and the other important welds must ensure the quality and should comply with the quality requirements on the drawings or of Grage Ⅱ of GB3323-87 or Grade Ⅰof JB1152-81 or Grade Ⅰof GB11345 B. 3.5.5 Requirement for Deviation of Installation After the installation (or after repair and change of rail), the installation quality is checked as per following technical requirements. 3.5.5.1 The limit deviation △S for span S of crane (Fig.30) should comply following requirements: Where the separable end carriage and the structure in which boring is done to directly install the wheel, if S≤10m，△S=±2mm; and if S＞10m, △S=±[2+0.1 (S-10)] mm. S is calculated as m. For the deviations to be simplified and rounded in the formula above, the values may be taken from Table 10. Table 10 S（m）

△S （mm）

10 ±2

＞10～15

＞15～20

＞20～25

＞25～30

＞30～35

±2.5

±3

±3.5

±4

±4.5

Fig 30 Span Deviation

3.5.5.2 There should be a camber over main girder and the camber at the mid-span is (1.0 ～1.4) S /1000. The maximum camber should be controlled within the range of S/10. 3.5.5.3 For the middle-rail box girder and semi-bias-rail box girder, the bending of main girder produced in the horizontal direction should not be more than S/200 (can only camber toward the footwalk side). For the bias-rail box girder, the bending is ±5mm if S≤16.5m and the bending is ±S/3000 if S＞ 16.5m. (The horizongtal bending refers to the value is measured from top flange plate.) 3.5.5.4 The trolley gauge deviation K and utmost deviation △K can not exceed the following values:

31


Fig 31: Trolley Gauge Deviation of Bias-rail Box Girder For the bias-rail box girder (Fig. 31), K + △K shouldn’t exceed ±3mm. For the symmetric middle-rail box girder and semi-bias-rail box girder (Fig. 32), at the end of span, K+△K should be ±2 mm; in the mid-span, K+△K should be +5+1 mm where S≤19.5 m and K+△K should be +7+1mm where S＞19.5 m.

Fig 32 Trolley Gauge Deflection of Symmetrical Middle-Rail or Semi-Bias-Rail Girder 3.5.5.5 The displacement deviation of the cntral line of steel rail from that of web of track girder (Fig. 33): for the bias-rail box girder, the displacement deviation of the cntral line of trolley rail from that of web of track girder should not exceed the following values: g≤δ/2 if δ≥12mm; g≤6mm if δ＜12mm.

Fig 33 Rail Installation Deviation 32


3.5.5.6 The elevation deviation △h of steel rail at the same cross section (Figs. 34 & 35): △h≤3mm if K ≤2m;

△h≤0.0015K if 2m＜K ＜6.6m; and △h≤10mm if K ≥6.6m. 3.5.5.7 The local planeness of main beam web will be measured by 1m leveling ruler. It should not exceed 0.7δ within 1/3 of the area from the top flange plate, and it should not exceed 1.2δ within other areas. 3.5.5.8 The camber of end carriage: h=W (±0.3W/1000)/1000 3.5.5.9 The bending of end carriage in the horizontal direction: q ＜W/2000 3.5.5.10 The elevation deviation of trolley at rail joints: d≤1mm. (The right view in Fig. 34) 3.5.5.11 Sidewise mismatch of trolley rail joint f ≤1mm (The left view in Fig. 34)

Fig. 34 Deviation of Rail at Joints For the installation and commissioning of electrical equipment, please see the booklet of electrical equipment..

3.6 Test and Inspection Procedure Because the condition of the manufacturer’s workshop is limited, the crane as a whole will be tested after it has assembled at Vizag site. The runing test will be done as per the following requirements after finishing the crane installation. For the large products which weight

≥300t, the end user should inform the

manufacturer of send the persons to join the test and identify it and reason out a conclusion together. Each time the running test has been finished, the relevant fasteners (especially the fixing places of wire rope in the hoisting mechanism) must be checked for loosening. If loose part is found, it must be tightened immediately. 3.6.1 Inspection and Preparation before Runing Test 3.6.1.1 Inspect the installation quality carefully and adjust improper places in time, thoroughly examine if the fastening parts are connected securely and reliably. 3.6.1.2 Inspect if the limit switches and other safety devices are intact. 3.6.1.3 Inspect if all lubricated points have been filled with appropriate amount of lubricating oil (grease) and the reducers have been filled with appropriate amount of gear oil as required. 3.6.1.4 Suspend the wheel in air and inspect if the rotation directions of the wheels are cinsistent after trying to energize the motor. 3.6.1.5 Inspect the other circuit systems for correct connection and examine the insulation resistance of circuit systems and all electrical devices using a megohmeter. 3.6.1.6 Make preparations for the relatively accurate weights (loads) appropriate to the rated load of crane and additional loads which is equal to 0.1 and 0.25 times of the rated load. 33


Fig 27 Sketch of Lifting and Erection of Main Girder 3.5.1 Installation Method of End Carriage Joint Put the bridge in sections on the level and parallel rails. The main girders and end carriages are connected according to the labeled graph of joint position and the bolt holes of main girders and end carriages. The connection should be done as specified in 3.5.2. 3.5.2 High Strength Bolting The steel structure of crane is connected by use of high strength bolts which load is transferred by frictional force. The high strength bolting has the characteristics of low stress concentration, good rigidity, more uniform force transfer and high load-carrying capacity. In order to guarantee the load transfer, the friction face of connected joints had been specially treated by sand blasting and coated with paint and reached the high roughness and skid resistance factor. When on-site erection, the special torque spanner wrenches accompanied with the crane are used at the site and proceed as per following steps: 3.5.2.1 The torque spanner wrench must be calibrated before use and they can only be used after calibration. Torque = arm of force ×gravity 3.5.2.2 The joint friction face should be cleaned and the uneven plates should be assembled after they meet the requirements. The friction face cannot have flap edges, burrs, weld splashings, welding scars, iron oxide scales, dirt and unnecessary painting and sludge. Around the hole, there should not be burrs. The friction faces that are ready for installation should be cleaned using the wire brush. The brushing direction should be vertical to friction stress direction. 3.5.2.3 The high strength bolting end plates should be tightly jointed each other. The gap between the contact surfaces due to tolerance on plate thickness and manufacture deviation or installation deviation should be treated as specified in Table 8 Table 8 Treatment Method for Clearance of Joint Plate No. 1

Sketch

Description When t<1.0mm, it should not be treated

27


3.6.2 No Load Test Rotate the brake wheel of every mechanism by hand so that all the drives be operated smoothly without seizure when the last-stage shaft (e.g. wheel shaft, drum shaft etc.) is rotated one turn and then start the motor of every mechanism to perform the continuous running test without load. The hoisting and traveling mechanism are tested each for not less than 10 minutes. All the drives should be operated smoothly without vibration, noise, rail block, skew traveling, clogging, twisting, oil leakage etc. Inspect the limit switches and other safety devices for reliability and adjust the degree of tightness for cable. 3.6.3 Static Load Test (Circuit of Weighing Devices Being Disconnected) The static load test mainly aims to inspect the main girders of crane bridge, relevant important metal structure and load handling device. The steps are as follows: 3.6.3.1 Firstly, lift the load that is smaller than the rated load and perform the test run for several times. 3.6.3.2 Secondly, lift the rated load and perform the test run to and fro along the whole bridge for several times. 3.6.3.3 Discharge the test load, drive the trolley to the end and measure the camber of main girder, or determine the zero line of girder over the girder post on the basis of the actual height of girder. 3.6.3.4 Drive the trolley to the middle of span, lift 1.25 times of the rated load gradually (i.e. loads are increased gradually) 100 mm above the ground, suspend and stop it in air for 10 minutes, and then dismantle the load and inspect if there is permanent distortion for main beam. In this way the test is repeated three times and the bridge should not have permanent distortion. Special attention must be paid: When 1.25 times of the rated load is lifted, it should be lifted 100mm over the ground once, suspended and stopped in air for ten minutes. Furthermore the relevant fastening pieces (especially the places where the wire ropes are fixed in the hoisting mechanism) must be checked after finishing the above-mentioned test each time. If it is found that the fastening parts are loose, then they must be fastened immediately. 3.6.3.5 After that, drive the trolley to the end of bridge and measure the actual camber of main girder. The measured value (camber in the mid-span) should be within the scope of (1.0～1.4) S/1000. 3.6.3.6 Finally, lift the rated load to check the deflection value of main girder. It should be less than S/1000 (calculated from the actual camber). 3.6.4 Dynamic Load Test (The circuit of weighing devices B eing Disconnected) Lift 1.1 times of the rated load by hoisting mechanism, respectively start every mechanism to perform the forward and backward test. The running test time for every direction cannot be less than 10 minutes (It should has pause time as per the duty.) or for not less than 10 times as per the specified motions. At this time the test should reach the following requirements: The performance and movement should reach the operating and design requirements; the connection and fastening part should be firm and reliable; the mechanisms should be operated normally without shock; the brakes can be acted flexibly and reliably; the reducers and gear pair are engaged correctly without noise, the lubrication system is in good order; the temperature rise does not exceed the specified value; and the limit switches, safety and protective devices and interlocking devices are actuated correctly without any trouble.

34


Chapter IV Operation of Overhead Traveling Crane

Table of Contents 4.1 Requisitions for Operator ..............................................................................................................................36 4.2 Precautions and Safety Inspection before Operation.....................................................................................36 4.3 Precautions and Safety Inspection during Operation ....................................................................................37 4.4 Precautions and Safety Inspection after Operation .......................................................................................38 4.5 Crane Operating Procedure as Shown in Booklet for Electrical Equipment .................................................39 4.6 Operating Procedure, Method and Precautions during Stoppage of Crane ...................................................39

35


Operation of Overhead Traveling Crane 4.1 Requisitions for Operator The operator must 4.1.1 be trained and pass the exam. 4.1.2 be familiar with the structure and technical performance of every crane mechanism to be operated. 4.1.3 be familiar with “Safety Rules for Lifting Appliances” and the relevant laws. 4.1.4 be familiar with the precautions taken before, during and after operation and the requirements for safety inspection. 4.1.5 be familiar with the performance and positions of safety and protective devices. 4.1.6 be familiar with the basic knowledge of motor and electrical equipment and parts. 4.1.7 be familiar with the daily maintenance and basic repair knowledge. 4.1.8 remember: I don’t hurt myself, I don’t hurt others and I’m not hurted by others. 4.2 Precautions and Safety Inspection Before Operation Please see Table 11. Before handling the materiel, no matter how many, test the brakes. Firstly, lift the materiel about 500 mm from the ground, test the brakes (for lifting and lowering movements), apply the brakes during lowering movement to prove if the brakes are acted reliably, and then lift the material normally. Forbid work before the brakes of hoisting mechanism are proven reliable. Check the fixing rope clip and wedge joint, and tighten up the nut of rope clip at the beginning of end of thimble in turn immediately after the initial static load test has been finished. and the wire rope replaced and loaded. 4.2.1 Firstly confirm if the power supply and voltage are normal. Close the door of every passage, check if every limit switch is in the proper position and determine if the switches and joysticks of electrical devices are in the normal position. 4.2.2 Check if the brakes are normal. 4.2.3 Check if the fixation for both ends of wire rope is normal. 4.2.4 Check if the fastening bolts of drum coupling are loose and the fastening hold-down device at the end of wire rope on the drum is reliable. 4.2.5 When the hook is located at the lowest point of working position, the wire rope wound on the drum should not be less than 2 wraps to be left except the number of wraps for fastening the rope end. 4.2.6 Fill every lubricated point with lubricating grease as specified. 4.2.7 Check if there are any articles loose keeping on the crane. 4.2.8 Check if there are any articles which may block travel on or near traveling rails. 4.2.9 Start the crane, operate it at low speed without load, and then normally do it after confirming the safety and protective devices are normal.

36


Table 11 Safety Inspection before Operation No. 1

Inspection Item

Inspection Method

Check if there are any barriers in the operating scope of

Visual check

crane or not.

2

Check the condition of power supply system of crane

Visual check

3

Check the condition of power supply system of trolley

Visual check

4 5

Check the condition of the wire rope in the groove setting

Visual check

in place on the drum and pulley block Check the condition of fixure and lubrication of the ends of

Visual check

wire rope

6

Inspect the brakes and brake wheels

Visual check, knock gently

7

Inspect the movement of every brake

Start-up

8

Check every instrument board and indicator light

Start-up

9

Check the movement of every safety switch

Start-up

10

Check the movement of joystick and button

Start-up

11

Recovery situation of last fault position

movement

4.3 Precautions and Safety Inspection during Operation Please see Table 12. Start the mechanism and apply the brake smoothly; stop accurately; harmonize the mechanism movement, reduce the work cycle time; any people and device accident donot happen. When one motor is damaged, one brake fails, and one wire rope or two digonal wire ropes are broken during operation, the crane should be stopped for repair and inform the commander of it. If abnormal sound occurs during operation, the crane must be stopped immediately and the power supply is cut off for checking it. The lifted load should be lowered to the ground at low speed. and inform the commander of it. Sudden power failure happens or voltage in the circuit descends rapidly during operation, all the controller joysticks should be turned back to zero position as quickly as possible, the main switch cut off and it informed to the commander. The operator must not leave the work post and should warn any people not to pass the dangerous area. Refuse to operate where the rated load is exceeded; Refuse operation where the load is not clear. Refuse to operate where the working area is sombrous and the operator canot see distinctly the field, the lifted load and command signals are not clear etc. Adjusting the brake of hoisting mechanism is forbidden where there is load on the hook. 4.3.1 The operator must concentrate the energy on the work and not chat with other people, smoke and eat during operation. 4.3.2 The operator must ring or give an alarm before starting the crane. When the crane approaches to people, the operator must ring off and on or give an alarm. 4.3.3 Firstly start each of the mechanisms to confirm if it can be operated normally. 4.4.4 When each mechanism is started and there is people at the travel route, t he operator must give an alarm. 4.3.5 The operator must obey the command and signal, and donot start the crane before the cases are clear. The crane must be stopped whenever a stop signal is given, 4.3.6 Operating three or more mechanisms at the same time is forbidden. 37


4.3.7 When lifting the load, the traveling and traversing mechanisms should be started and arrested smoothly. 4.3.8 When one trolley is operated separately for the crane with double-trolley, the other trolley must be moved to closely limiting position. 4.3.9 When the main hook is operated separately, the auxiliary hook must be lifted up to close upper limit, but donot touch the limit switch. 4.3.10 The limit switch is never allowed to stop the crane normally, but must be often kept in the correct and normal condition. 4.3.11 Use of the emergency stop device to interrupt the normal operation is strictly prohibited. 4.3.12 The switch and junction box must not be opened before cutting off the power supply. 4.3.12 Use of the low speed gears for the mechanisms for a long time is prohibited but only allowed in the three cases of starting, braking and aligning operations. The mechanism should be operated at high speed gears in the normal working cases except for the above-mentioned three working conditions. Table 12 Safety Inspection during Operation No.

Inspection Item

Inspection method

Abnormal smell, abnormal sound, abnormal heat, abnormal shock

1

Smelling, listening,

(including winding, iron core, collector ring)

touching

2

Abnormal situation of voltage and current

Visual check

3

Abnormal change of external environment

Visual check

4.4 Precaotions and Safety Inspection after Operation See Table 13. Table 13 Clean and check the condition of every mechanism. Complete the operating log and make preparations for crew change. 4.4.1 The crane is parked at the designated position. 4.4.2 The trolley is parked at closely limiting position on the side of the operator’s cabin and the empty hook is lifted up to the closely limiting position. 4.4.3 All the controller joysticks and switches are turned back to the designated position in the operator’s cabin. 4.4.4 In order to keep it in the optimal condition when the crane is started next time, it must be confirmed if the power supply to every safety device is sufficient. Table 13 Safety Inspection after Operation No.

Inspection Item

Inspection Method

1

Check if the crane is stopped in the right position.

Visual check

2

Check if there is oil leakage for every part, especially the reducer and brake.

Visual check

3

Check if there is abnormal temperature rise for the motor and reducer.

4

Check if controller joysticks and buttons are reset

Visual check

5

Check if the power supply switch is disconnected

movement

6

Operating log

Observation

7

Lock the operator’s cabin

Visual check

8

Clean the crane (motor, collector ring etc.)

Visual check 38

Touching


4.5 For the Crane Operation Procedure, see the booklet for Electrical Equipment. 4.6 Operating Procedure, Method and Precautions during Stoppage of Crane Where the Crane is stopped to operate for a certain reason, the following work should be done: 4.6.1 The crane is moved to the position that can not affect other cranes. If the above requirement canot be met because of condition limit, the reliable protective measures should be taken or the supervisor provided. 4.6.2 All the controller joysticks are put to zero position. 4.6.3 Cut off the main power supply switch, lock it or hang the sign plate. The sign plate should be put in the position where the persons concerned can read it distinctly.

39


Chapter V Maintenance & Repair

Table of Contents 5.1 Requisitions For Maintenance Personnel ......................................................................................................41 5.2 Scope of Maintenance ...................................................................................................................................41 5.3 Safety Rules during Maintenance Work and Overhaul Period......................................................................41 5.4 Preventive Maintenance (Maintenance Work and Frequency) .....................................................................41 5.5 Wear (Operating) Limit (Discard Standard)..................................................................................................44 5.6 Failure and Repairing Maintenance ..............................................................................................................46 5.7 Maintenance for Long-time Parking .............................................................................................................51 5.8 Lubrication ....................................................................................................................................................51

40


Maintenance & Repair 5.1 Requisitions For Maintenance Personnel The maintenance personnel should: 5.1.1 Have been trained professionally and have passed the exam 5.1.2 Master and understand the function and setting of safety and protective device in this product. 5.1.3 Master and understand the structure and driving principle of each of mechanisms and components in this product. 5.1.4 Be familiar with the “Safety Rules for Listing Appliancese” 5.1.5 Be familiar with the maintenance regulations and frequency 5.1.6 Remember: I don’t hurt myself, I don’t hurt others and I’m not hurted by others. 5.2

Scope of Maintenance

5.2.1 Reliability and precision of Safety and protective devices 5.2.2 Condition of wearing of wire ropes and fixing of ends of rope 5.2.3 Condition of wearing, cracking and deformation of main parts and components 5.2.4 Condition of deformation, cracking corrosion of main load-carrying structures and welding, riveting and bolting; 5.2.5 Lubricating condition 5.2.6 Electrical drive and control system etc. (see the booklet for electrical equipment) 5.3 Safety Rules during MaintenanceWork 5.3.1 Move the crane to the designated maintenance area 5.3.2 Cut off the power supply switch to prevent it from being reenergized without authorization: inspect all the functions after power-off and confirm all the circuits have been disconnected. 5.3.3 Hang the safety sign board at appropriate positions. 5.3.4 Operation should be done within the range of platform or guardrail 5.3.5 Wear the safety wares during operation 5.3.6 Use the safety and reliable wire ropes to handling the heavy load properly 5.3.7 When welding around the bearing and circuit, isolation and protective measures should be taken. 5.3.8 When the crane is at the operating condition, maintenance, repair and manual lubrication will be forbidden. 5.4 Preventive Maintenance (Maintenance Work and Frequency) 5.4.1 For the maintenance of safety and protective devices, see Table 14. Table 14 Maintenance of Safety and Protective Devices Description Rotating-type limit switch for lifting Weight-type

Location At the tail end of drum On

Scope of Inspection

Time Interval

Check if the contacts are acted accurately and powered off and

Each shift

reset normally. the

trolley

The weight is hung without 41

Each shift

Special Cue


Description

Location

Scope of Inspection

Time Interval

limit switch for frame

blocking and powered off and

lifting

reset normally.

Travel

limit

switch Electronic scale Lifting

load

limiter Buffer Door switch Protective hood Safety cover and guard frame Rail sweeper

It

On the bridge

is

Swung

Display

shaft (base)

normal.

At the drum base the

and

powered off and reset normally.

Under the sheave

On

flexibly

bridge

(trolley frame)

and

precision

are

It gives an alarm and cuts off the power according to quantity Keep cushion stroke without loose connection

At the bottom of Contact, power-off and reset each door

are exact or not

At each rotating No loose connection exists and component

the appearance is intact.

At exposed wires In front of wheel

No loose connection exists and the appearance is intact. No loose connection exists and the appearance is intact.

Special Cue

Daily Weekly Daily Daily Daily Weekly Daily Weekly

Note: For the safety brake maintenance, see the Booklet for Electrical Equipment in the supplier’s documents accompanied with the crane. 5.4.2 For the maintenance of mechanisms, see Table 15 Table 15 Maintenance of Mechanism Description

Location At the end of motor

Coupling

(disk)

Check whether it has eccentricity and abnormal noise

At the high speed

Check whether it has

end of reducer

eccentricity and abnormal noise

At the low speed end

Check whether it has

of reducer

eccentricity and abnormal noise

Drum coupling Brake wheel

Scope of Inspection

Each mechanism

Check whether it has eccentricity and abnormal noise Wear status Too high temperature

At the driving end of Heat generation and abnormal

Roller bearing

motor

noise

At the non-driving

Heat generation and abnormal

end of motor

noise

At both ends of each

Heat generation and abnormal

shaft of reducer

noise 42

Time Interval Daily Daily Daily Daily Weekly Daily Daily Daily Daily

Special Cue


Description

Location

Scope of Inspection Check whether the detent has crack or not

Ratch

detent

device

Main

hoisting

reducer

Check whether the pin shaft has any play or not Check whether the spring has distortion or not

Motor

Winding iron core collector ring

Too high temperature Check if the wire rope is connected tightly or not

Wire Rope*

Hoisting mechanism

Check if grease exists on the rope or not Check if wear and broken wires exist or not

Time Interval Weekly Weekly Weekly Daily Each shift Daily Each shift

Sheave

Hoisting mechanism

Check if swing exists or not

Weekly

Drum

Hoisting mechanism

Check if axial play exists or not

Weekly

Tooth surface damage Quantity lubricating oil and oil Reducer

Brake

Wheel Equalizing bogie

Each mechanism

Each mechanism

Travel mechanism Travel mechanism

leak

Semiyearly Weekly

Body heat

Daily

Vibration and noise

Daily

Torque change

Daily

Even clearance at both sides

Daily

Spring acting force change

Daily

Inclination exists or not

Daily

Wear of yread and wheel flange

Quarterly

Shaft play exists or not

Quarterly

Shaft hole enlarging exists

Quarterly

Shaft hole

Wear or not

Yearly

Liner

Wear or not

Semiyearly

Hook tip

Wear or not

Yearly

Connecting bolt

Loose or not

Quarterly

Drum clamp

Fasten or not

Each shift

Drum coupling

Fasten or not

Each shift

Motor frame

Fasten or not

Weekly

Connecting

Brake base

Fasten or not

Weekly

bolt

Reducer gearbox

Fasten or not

Weekly

Drum

Fasten or not

Hook Buffer

supporting

base Each coupling

Fasten or not 43

Weekly Weekly

Special Cue


Note: Maintenance of wire rope shall be done according to GB5972 “Appliable Specification for Inspection and Discard of Wire Ropes for Lifting Appliances” and GB6067 “Safety Rules for Lifting Appliances”. 5.4.3 For the maintenance of Structure, see Table 16. Table 16 Maintenance of Structure Item

Location

Scope of Inspection

Time Interval

Special Cue

At the connection between main girder Loose or not Connect bolt

Yearly

and end carriage Connection

of

trolley frame Platform railings

Loose or not

Yearly

Loose or not

Quarterly

At the connection between main girder Crack or not

Yearly

and end carriage At the connection between

Welds

bottom

flange plate and web

Crack

or

not

(pay

special attention to the

Semiyearly

Treated in time

plate in mid-span of weld arcing area) main girder Each

components

basement

Crack or not

Semiyearly

Crack or not

Daily

Wear on rail surface

Daily

Rail

On the bridge

Cable tray

On the bridge

Shaking or not

Daily

Carrier

On the bridge

Flexible or not

Daily

Electrical Room and

Temperature

operator’s cabin

with the standard or not

Air cooler

comlies

Daily

5.5 Wear (Operating) Limit (Discard Standard) See Table 17 Table 17 Wear limit Description

Tooth surface wear

Affiliated Component Hardened tooth surface of hoisting reducer Other reducers

Tooth

flank Mating surface

Wear Limit 20% of the first-stage dirving hardened layer 30% of the second-stage dirving hardened layer 40% of the third-stage dirving hardened layer 15-20% of the original tooth thickness 30%

pitting

Pitting depth

10% of the original tooth thickness

Gear crack

All reducers

Crack, tooth rupture 44


Description Coupling gear tooth

Affiliated Component

Wear Limit

Hoisting mechanism

10% of the original tooth thickness

Travel mechanism

15-25% of the original tooth thickness

Each mechaniam

Crack, tooth rupture

Main hoisting mechanism Hoisting mechanism

20% of the brake disc wear compared with the original thickness 30% of the brake wheel flange wear compared with the original thickness 40% of the wheel flange wear compared with the original

Travel mechanism

thickness

Brake

Wheel face ruggedness reaches to 1.5mm 50% of the brake disc wear compared with the original thickness Each mechanism

Plastic deformation exists in the spring 5% of the small shaft or shaft hole diameter wear compared with the original diameter wheel (disc) cracking 15% of the tread thickness wear compared with the original thickness 50% the wheel flange wear of compared with the original

Wheel

Each travel mechanism

thickness 20% of the wheel flange bending deformation compared with the original thickness Diameters of driving wheels are not equal

Main hoisting mechanism with M7 Auxiliary

hoisting

mechanism Wire Rope*

Renewed at intervals of 8 monthes

(Main

hoisting mechanism with

7% of the original diameter

M6) 7 Broken wires / pitch Seriously bruised or bent Each hoisting mechanism

Cage type distortion and strand being extruded Serious external corrosion and deep pits occuring on the surface

Thickness

of

sheave

of

groove

groove wall Sheave

Diameter

bottom of sheave

10% of the original wall 25% of the wire rope diameter cracking

45


Description

Affiliated Component

Wear Limit 10% of the tube wall wear compared with the original wall

Drum

Each travel mechanism

thickness cracking

Roll bearing

Main hoisting mechanism

Be operated for 2500 hours

Others

Be operated for 6300 hours Components being broken up Detent cracking

Ratch detent

Main hoisting mechanism

10% the spring wear compared with original dimension The spring has plastic distortion and, cannot be restored 30% of the serious wear compared with the original

Rail head Steel

Main beam, end carriage, plate

trolley frame

thickness 10% of the original thickness

corrosion

The opening of hook mouth being increased by 30% compared with the original thickness The torsional deformation exceeds 10° Plastic deformation occurring at the dangerous section or Hook

Each hoisting mechanism

hook shank When the laminated hook sleeve is worn by 50% compared with the original dimension, it should be discarded. When the spindle of laminated hook is worn by 5% compared with the original dimension, it should be discarded.

Painting

Crane as a whole

More than 10% of the Paint film being peeled off, cracked and chapped.

Deflection of

S/1700 under horizontal line. (if it cannot be repaired, it must

main girder

be discarded)

Note: Use, maintenance and discard of wire ropes should comply with GB 5972-86 “Appliable Specification for Inspection and Discard of Wire Ropes for Lifting Appliances” and GB6067 “Safety Rules for Lifting Appliances”. 5.6 Failure And Repairing Maintenance 5.6.1 For the failures in the mechanical equioment and repair, see Table 18 The part to be renewed due to failure in the mechanical equipment must be fully in accord with the requirements as specified on the original design drawings. Table 18 Mechanical Failure and Repair Component

Failure

Reason and Consequence

46

Corrective Measures


Component

Failure


Corrective Measures

Bearing failure, gears and bearings lack of lubricating oil. (The temperature Gearbox heating

is not

more than ambient medium temperature of 40℃.

The

absolute value is not more

Inspect

the

lubrication

condition and

of

bearings.

Change the lubricating oil and bearing if necessary.

than 80℃ as normal) Planetary gear box body over heat leak

temperature

of

lubricating oil in the box is more than 80℃.

Reducer Oil

The

occurring

between split faces or at the bearing cover

Loose

Vibration

and

damaged seal gule

axle

cooling

device.

Lubricating oil is circulated and cooled between gear box and

Fasten, clean, re-coat with seal gule.

connection

malposed

the

cooler.

connection

Loose

Install

center

and of

connecting part

Re-adjust, fasten, secure the base Replace the pin with new one,

Vertical

reducer Deformed connecting hinge

jumping

and damaged pin

adjust and fasten the hinge basement, and replace the key with new one.

Overload or fatigue fracture, Gear pair

Tooth rupture

cracking occurring at the root

Changed

of tooth and destroyed drive The peeling-off area is more than 30% of the working area Tooth face pitting

Peeling off

and the pitting depth is more than 10% of the tooth thickness. Changed. The wear limit of hoisting mechanism

Tooth is worn.

Runout

when

starting

is

10%

of

the

or original tooth thickness. If that

arresting

of travel mechanism is 15-25%, the gear pair should be replaced with new one.

Tooth glueing

Inproper lubrication

Wheel spoke and rim

Damaged gear may lead to

cracking

breakage of driving chain

47

Changed Renew the hoisting mechanism but

repair

mechanism

the

traveling


Component

Failure

Reason and Consequence Improper

fabrication

Corrective Measures

and

assembly: insufficient contact Noise and clash

face, scars existing on the

Guarantee

tooth,

running-in with no load

tooth

tip

gnawing

the

precision,

against the tooth root and assembly deflection Half body cracking

Damaged coupling

Changed Change the coupling for the

Jumping Bolt hole is worn.

when

the

crane

hoisting

mechanism. For other

being started and the bolt

machined hole, change the bolt

being nipped off.

or repair welding for hole and remachine.

Poor installation precision, insufficient

Tooth is damaged.

rigidity

of

bracket, lack of lubricating

Coupling

grease and damaged drive.

Filled with grease termly and renewed when the coupling is worn by 15-25% of the original tooth thickness (10% for main hoisting mechanism) Renew the coupling for the

Key way is worn.

Key being out of the key way

hoisting

mechanism,

leads to falling of the load.

welding

for

the

repair traveling

mechanism. Jumping

Tooth is damaged.

during

operation

resulting in breakage

Key is damaged and

The

key

is

snipped

tooth is jumped.

driving chain is broken

and

Renew the gear. Renew the key. Filled with grease. Check it for

Being not rotated.

Mandrel abrasion

abrasion and the condition of

Sheave

bearing. Sheave

groove

is

unevenly worn. High temperature

Wire rope is tilted pulled

Lifting the load by tilted wire

when lifting the load.

rope is prohibited. Changed

Lack of Lubricant, load being

Clean

the

bearing

using

increased. There is dirt, crack kerosene, fill it with grease or

Rolling

and little pit.

bearing

The end play is too small, Noise

change it.

rotating part is blocked or Adjust or change part broken up. Turning

Load Brake

can

not

be

arrested by brake and slip distance is long.

joint

lubricant

drops

is to

locked, brake

Lubricate the turning joint with

surface, brake shoe is worn

oil, clean the vane wheel and

too seriously, vane wheel in pad using kerosene, replace push

bar

is

not

rotated brake linings

flexibly and hook slides.

48


Component

Failure


Corrective Measures

There is glue on the brake lining, the spring Can not be opened

tension is

too great, the vane wheel in

Clean the brake lining, adjust or

push rod or the motor fails

replace the spring.

and

driving

chain

is

damaged.. The brake is renewed for the The brake is swung, not Key way is widened.

hoisting mechanism and its key

applied exactly and the hook way can be slotted on the slips.

malposition

for

the

travel

mechanism. Rupture may lead to the Brake wheel

brake wheel flying off to hurt

Cracking

people and the load falls

Renew

down. Ratchet wheel

and

detent device

Detent distortion and

Abruption and driving chain

cracking

breakage

Spring cannot be reset

The drive is damaged.

Noise or shock

Wheel flange is worn badly

Skew traveling only in one direction all the way Skew

traveling

and

is

backward

directions

traveling of wheel

Renew (gurantee material and heat treatment) Renew

The horizontal deflection of wheel is off gauge and the skew directions at both ends

Readjust

are not opposite.

different in the forward

Skew

Renew

Motors or brakes are not rotated

or

applied

Inspect and adjust

synchronously.

Skew traveling of wheel

Inspect and adjust rail centers

only at one section of Rail installation is wrong.

and elevation error at the same

travel

section.

The

wheel

always

nibble against the outer edge (or inner edge) Skew

traveling

trolley wheel

The span of wheel or rail is wrong.

of Main girder sinks and is bent inward.

Inspect and adjust

Repair the main girder When the wheels are adjusted, the driven wheels should be selected and one is used to solve several problems as far as fossible.

49


Component

Failure


Corrective Measures

The wheel flange is worn The

wheels

run

unduly and the wheel travels

unstably and on the

on

skew.

resistance, thus resulting in

Wheel

the

skew

with

high

uneven rail.

Replace the wheel with new one when abrasion comes up to 50% of the original dimension and adjust the wheel.

After abrasion, the wheels in diameter are different, thus resulting in resistance being

Remachine or replace the wheel

increased. The motor is operated with overload, the air path is blocked, Motor

Too high temperature

the

winding

is

earthed, the stator and rotor are

touched

and

rubbed

Use of motor is stopped and the fault is eliminated.

against each other and the bearing is worn. Wire rope

As per GB5972

Note: If the type, specification and strength of the wire rope to be changed must be completely consistent with those of the wire rope that was originally designed. The wedge socket and rope clamp must be also identical to thosethat were originally designed. 5.6.2 For the structural fault and fault recovery, see Table 19. The recovery of structure fault should be performed by the skilled professional technician; or otherwise the fault may enlarge the deformation, thus resulting in evil consequence. Table 19 Structural Fault and Fault Recovery Component

Failure

Main girder and

end

Reason and Consequence Stress

Weld crazing

carriage

concentration,

overload, crack increase may lead to girder rupture.

Corrective Measures Distribute stress and repair welding to prevent the weld from being enlarged. Prohibit overload. Rectify the main girder by

Camber disappears Main girder

Overload, trolley will travel

flame,

in creep speed.

increase

its

it

strength

and and

rigidity. Sidewise bending is off The horizontal rigidity is not

Rectify the main girder by

gauge.

flame.

End

Sidewise bending is off

Carriage

gauge.

enough. The horizontal rigidity is not enough.

The

Distortion

connection

strength is insufficient. Connection

Rail

reinforce

is

loose,

technician.

rail

centers are off gauge, travel is difficult and there is noise. 50

Repaired by the professional

Readjust and tighten bolts.


Equalizing

Welding

beam

distortion

Laminated hook Trolley frame

cracking

and

Too great lateral force and skew traveling of wheel.

Adjust and repair

The clearance between plates Rivets are loose.

is increrased, thus resulting

Rivet again

in dificult hooking on. Local distortion

Local structure is weak and

Reinforce the place that is

subjected to oversize force

deformed

and the parts are damaged.

position of parts.

and

adjust

the

5.7 Maintenance for Long-time Parking If the crane is not in use for a long time, it should be covered in good condition, especially for electrical equipment. Theexposed machined surface should be coated with antirust grease. It must be thoroughly checked at intervals of 4 to 6 months. 5.8 Lubrication The lubrication of crane is a key to ensure the normal operation of crane, prolong the service life, improve the efficiency and promote the safety in production .Importance must be attached to the lubricating work of crane. The lubricating equipment should be maintained frequently and carefully. Operator should often check if the lubricating system can work normally. 5.8.1 Lubricated Positions For the cranes with small and medium lifting capacities, the individual lubrication is mostly used to fill the lubricated points with lubricating oil by oil gun. For the cranes with high lifting capacities, the central lubrication is mostly used to periodically feed the lubricating oil with a pump to all the lubricated points via the oil pipes which are concentrated in one place.(The lubrication methods are determined according to the contract.) 5.8.1.1 Centralized Lubrication for Trolley See Fig. 35. Main hoisting mechanism: for the fixed sheave bearing, the grease is fed from the shaft end of pulley via oil pipe . Drum bearing: the grease is fed from the upper cover of bearing. Trolley traversing mechanism: for the wheel bearing, the grease is fed from the end cover via oil pipe .

Fig 35 Sketch of Trolley Centralized Lubrication System 51


5.8.1.2 Centralized Lubrication of Crane Traveling Mechanism Each of the cranes is provided fitted with two sets of lubricating system. The grease will be fed from the end cover of wheel to the wheel shaft and the grease (or molybdenum disulfide grease) will be fed from the shaft end to the pin shaft, see Fig. 36.

Fig. 36 Sketch of Centralized Lubrication System of Crane Traveling Mechanism 5.8.1.3 Lubrication of Reducer The reducer is provided with oil pump for Lubrication (Fig. 37) or splash lubrication outside of it.

Fig. 37 Sketch of Lubrication of Vertical Reducer 5.8.1.4 Lubrication of molybdenum disulphide grease For the pins and shafts, the grease is coated on their fitting places. 5.8.1.5 Lubrication of Purchased Bearings The periodic coating method will be used and performed according to the instructions for the purchased bearings accompanied with the crane. 5.8.2 The lubricant and lubricating period are as shown in Table 20. Table 20 Lubricant and Lubricating Period Lubricated Place

Oil

(Grease)

Period Main

Wire rope

Filling hoisting

mechanism: daily Auxiliary

hoisting

mechanism: 15 days

Oil (Grease) Filling Method Coated by greaser Coated

52

Recommended

Oil

(Grease) Special grease specially used for wire rope Special grease specially used for wire rope


Lubricated Place

Oil

(Grease)

Filling

Period

Oil (Grease) Filling Method

Recommended

Oil

(Grease)

At the earilier stage of operation: the oil is changed

Reducer

within

300

hours after operation,

Fill

oil

as

per

scale

L-CKC320

industrial

indication

heavy-duty EP gear oil

Oil gun presses oil until

#2 universal lithium based

overflow.

grease

Oil gun presses oil until

#3

overflow.

base

and then it is changed once half a year. Gear coupling

Quarterly

Universal

Monthly

coupling

compound

calcium

Fill oil to every oil hole in sequence. If the oil hole is Drum coupling

Monthly

located at the bottom, then

#3 EP lithium based grease

the oil gun presses oil until overflow. Drum gear disk coupling

Monthly

Bearing

Monthly

Motor

Yearly

Hinges

at

equalizing bogies

Monthly

etc. Hinges of brakes, limit switches etc.

Quarterly

Fully coated with grease

#2 universal lithium based grease

Oil gun (oil pump) presses

#2 universal lithium based

oil until overflow.

grease

Fully coated with grease Oil gun presses oil until overflow. Fully coated with grease

#2 universal lithium based grease #3 mixed calcium grease #2 universal lithium based grease

Note: The lubricating oil (grease) must not be mixed with that of different brand and must be clean. 5.8.3 Lubricating Device 5.8.3.1 Motorized several-point lubricating pump (Fig. 38) When the reducer is driven by the motor, the lubricating grease is discharged by the pressure oil pump via many holes and fed to all the lubricated points via oil pipe. Attention must be paid during operation: Before operation, HL-20 gear oil is filled into the first-stage reducer until the specified oil level. When filling grease to oil reservoir, it must be filled by manual oil pump or electrical oil pump from the filling aperture of oil reservoir. Starting and operating the crane is strictly prohibited when there is not any grease in the oil reservoir. Motor connection must be done as per the direction requirement outside of oil reservoir, do not allow the reverse; clean the screen of oil filler regularly; keep clean, prohibit to open the cover to fill grease in order to avoid the dirt entering into pump; please read the instructions for the method of adjustment amount of oil and disassembly of pressure oil pump.

53


Fig. 38

Sketch of PPB18/36 Oil Pump

5.8.3.2 Electrical One-way Grease Pump (Figs. 39 and 40) The grease is discharged by the oil pressure pump which is driven by the reducing motor and directly fed to all the lubricated points. The oil pipes and nozzles access to all the lubricated points are individually concentrated on feveral supports at appropriate positions.

Fig. 39 Sketch of

Fig. 40 Outside View of

Single-point Electrical Lubricating Pump

Single-point Electrical Lubricating Pump

5.8.3.3 Manual Grease Pump (Fig. 41)

54


Fig 41 Sketch of Manual Grease Pump

55


Chapter VI Components

Table of Contents 6.1 Wire Rope .....................................................................................................................................................57 6.2 Brake Wheel (Disk).......................................................................................................................................60 6.3 Rolling Bearing .............................................................................................................................................60 6.4 Transmission Shaft........................................................................................................................................60 6.5 Motor.............................................................................................................................................................61 6.6 Brake .............................................................................................................................................................62 6.7 Reducer .........................................................................................................................................................63 6.8 Drum Assembly.............................................................................................................................................66 6.9 Fixing Sheave Block .....................................................................................................................................67 6.10 Wheel Assembly .........................................................................................................................................68 6.11 Coupling......................................................................................................................................................69 6.12 Hook Block .................................................................................................................................................73 6.13 Crane Load Limiter .....................................................................................................................................73 6.14 High Temperature Air Fan ..........................................................................................................................76 6.15 Buffer ..........................................................................................................................................................78 6.16 Cable Carrier ...............................................................................................................................................79

56


Components 6.1 Wire Rope 6.1.1 Wire Rope Construction The selection for wire rope of crane should comply with GB 8918-2006 Wire Ropes for Important Purpose, see Fig. 42.

Fig. 42 Round-Strand Wire Rope Construction -----Point contact lay wire rope --- all layers of wire with the same diameters The wire rope with 19 wires is thicker and can endure abrasion and erosion, so it is widely used. The wire rope with 37 wires has good flexibility. ----Liner contact lay wire rope---all layers of wire with different diameters Type W (also referred to as Warrington) wire rope is large diameter fine-wire rope Type X (also referred to as Seale) wire rope is wire rope with coarse-wire in outer layer. Type T is filler wire rope. ----Lay of wire rope (Fig. 43)

Fig. 43 Sketch of Lay of Wire Rope ---- Rope Core Hemp core (FC)

Natural hemp core (NFC)

Steel core (WC)

Strand core (WSC)

Resultant hemp core (FC)

Independent wire rope core (IWRC)

----Wire rope grade---divided into five grades, i.e. 1570

1670

1770

1870

1960 MPa

----The linear contact lay wire ropes are used in the crane, Type W or Type X, IWRC

57


6.1.2 Designation of Wire Rope E.g.: Dimension 6×19S－IWRC－1770－B－Z

6.1.3 For fixing of wire rope end, see Fig. 44.

Fig. 44 Fixing Method of Wire Rope End The ends of wire rope used in the crane are fixed using wedge-shaped thimbles (GB5783-2006) and rope clamps (GB5976-2006). The wedge-shaped thimbles (GB5783-2006) and rope clamps (GB5976-2006) should be selected as per wire rope diameter. The thimbles and rope clamps with wrong size are not allowed to use instead of them. The rope clamps should be located at the side of wire rope which is subjected to the load. The U-shaped bolts must be located at the end of wire rope and not be crossed in the positive and negative directions. The rope clamp should be so tightened that both ropes are bruised to about 1/3 of the original diameter height. After the rope clamps have been fixed securely and subjected to the load, they should be tightened up again. For the quantity of rope clamps required during fixing of wire rope using rope clamp, see Table 21. Table 21 Quantity of Rope Clamps Required during Fixing of Wire Rope Using Rope Clamp Diameter of Wire Rope Number of Rope Clamp

(mm)

7-16

19-27

28-37

38-45

3

4

5

6

58


Note: Two rope clamps (rope clips) are only required to use behind the wedge-shaped thimble. 6.1.4 Safety Factor of Crane Wire Rope The safety factor of wire ropes used in the overhead traveling crane is selected as per FEM “Design Rules for Lifting Appliances”. Table 22 Safety Factor of Wire Rope Group Clarification of Mechanism

Safety Factor

M6

5.6

M7

7.1

6.1.5 Maintenance and Replacement of Wire Rope For the maintenance of wire rope, attention should be paid to the following points: (1) The wire ropes should be prevented from be damaged (sparkle sprays), corroded or decreased in performance due to other physical and chemical factors; (2) The wire ropes must be kept in good lubricating condition. The lubricating grease should be used for the daily lubrication of wire rope; (3) It must be checked if the wire rope are fixed securely at each shift; (4) It must be checked if the wire rope are damaged or deformed. The change of wire ropes (including wedge-shaped thimble and rope clamp) must comply with the requirements for the type and specification of wire ropes that were originally designed, but the t ensile strength of wire rope should be ensured. Attention should be paid to the following points: (1) When the wire rope is uncoiled, it should be prevented from being knotted or distorted. (2) When the wire rope is cut off, measures should be taken to prevent the strands from be loosened. (3) When the wire rope is installed, it should not be dragged on the unclean ground, and wound around other objects. It should be prevented from being scored, ground, milled and unduly bent. 6.1.6 Discard of Wire Rope When one of the following conditions occurs, the wire rope should be discarded: (1) The the wire rope is obviously reduced in diameter; (2) The wire rope is seriously staved; (3) The wire rope is seriously bent. (4) The wire rope is seriously knotted. (5) The the wire rope is obviously increased in diameter. (6) The wire rope has cage distortion and the strand is squeezed out; (7) The wire rope is seriously corroded at its exterior, its surface has deep pitting and the wires are quite loose; (8) The outer layer of wire rope is worn by 40% of the original diameter; (9) The diameter of wire rope is reduced by 7% or more relative to the nominal diameter; For the others, please refer to GB 5972-86 “Practical Specification of Examination and Discard of Wire Ropes for Lifting Appliances”. The replacement of wire ropes used in the main hoisting mechanism of crane will be more strict than that of wire ropes used in the above-mentioned applications, the replaced wire rope can be still used in other applications if it is in the discarding condition. Normally the user can execute its respective regulations. 59


6.2 Brake Wheel (Disk) See Fig. 45.

Fig. 45 Sketch of Brake Wheel The brake wheel (disk) must be kept clean on the surface during operation. It should be checked if there is hard thing on the brake linings when finding out there is convex-concave on surface of brake wheel (disk). If any, it should be eliminated in time. When key way is enlarged in width, it’s allowable to slot the key way after stagger it at120 °. The installation error do not exceed the values in Table 23. Table 23 Allowable Installation Error for Brake Wheel (Disk)

≤250

＞250～500

＞500～800

Radial Runout

0.2

0.25

0.30

Axial Runout

0.15

0.20

0.25

Diameter of Brake Wheel (Disk)

The discard of brake wheel (disk): The brake wheel (disk) should be discarded right now when cracking occurs in it and convex-concave existing on it exceeds 1.5 and ca not be repaired. It should be rejected when the flange of brake wheel (disk thickness) for the hoisting mechanism is worn by 30% of the original thickness and that for the traveling and traversing mechanisms is worn by 40%.

6.3 Rolling Bearing Lots of rolling bearings are used in all the drives of crane. The state of bearing, good or bad, will directly influence the working performance of mechanisms and the main technical indexes of crane. Lubrication for bearings must be done in order to make the bearings rotate normally, avoid the direct contact of components on the surface, reduce the internal friction and abrasion of bearings, improve the bearing performance and prolong the service life of bearings. And it must be noted that the lubricating oil (grease) must arrives at the rolling position of balls (rollers) fo bearing. The rolling bearings must keep the play required during operation. The bearing needs to be replaced when the rollaway of inner and outer rings, and ball (roller) of bearing have abrasion, streaking, peeling, pitting and cracking on the surface or the radial clearance of bearing is increased by 0.2 mm. 6.4 Transmission Shaft Setting of the high speed shafts in the hoisting mechanism of crane (the low speed shafts is also fitted in the double reducer.), and setting of the low speed shafts in the traveling and traversing mechanisms are normally setting. The bending of shaft ≯1/2000，or otherwise the shaft should be straightened or replaced. If the bending is too great, vibration will occur at the high speed shaft. The low speed shaft will be replaced when the bending ＞1/1000 or ＞1 mm. The shaft should be so replaced to ensure the dimension precision, roughness, form and

position tolerance, material and heat treatment comply with the the requirement on the original drawing. 60


6.5 Motor 6.5.1 Type YZR Motor The type YZR three-phase wound rotor asynchronous motors for the cranes and metallurgical equipment have insulation class of H and protection class of IP54. The motors of this kind have higher overload capacity and mechanical strength, and are applicable for use in the lifting equipment which have short time or discontinuous periodical operation, frequent starting and braking etc and obvious vibration and impact. The motors with insulation class of H are suitable for use in the metallurgic plant at the ambient temperature being not more than 60℃. The reference duty of motor is S3 and the reference cyclic duration factor with load is 40%. The protection class is IP54. The additional resistance or reactance must be connected in series when the motor is stared so as to limit the average value of staring current exceeding 2 times of the rated current for each duty. The cover of inspection window on the end cover, the cover of terminal box and the outlets outgoing line should be covered during operation so as to prevent water, dust, greasy dusty etc. entering into them. See Table 24 for the allowable temperature rise of every heating element during operation of motor. See the instruction manual for construction of motor accompanied with the crane. Table 24 Allowable Temperature Rise of Every Heating Element During Operation of Motor Heating Element Winding Iron Core Collector Ring Bearing

6.5.2

Measuring Method

Insulation Class of F

Insulation Class of H

Ambient Temperature 40℃

Ambient Temperature 60℃

100

100

95

115

95

80

95

115

Resistivity Method Heat Indicator Method Heat Indicator Method Heat Indicator Method

Type YZP Motor Type YZP three-phase VVVF asynchronous motors for the cranes and metallurgical equipment are

motors that supplied by frequency converter and have insulation class of H and protection class of IP54. The motors of this kind have wide scope of speed regulation, higher overload capacity and mechanical strength, and are suitable for in the lifting equipment which have short time or discontinuous periodical operation, frequent starting and braking etc and obvious vibration and impact. The rated voltage of motor is 380V, the rated frequency is 50Hz. The motors can be speed controlled continuously in the scope of 5 ～100Hz, among them, 5-50 Hz is for operation at constant moment of rotation and 50 ～100Hz is for operation at constant power. See the instruction manual for construction of motor accompanied with the crane. 6.5.3 Inspection of Motor during Operation (1) Firstly check if the foundation of motor is mounted tightly and securely and has definite rigidity; the mounting surface is flat so as to avoid harmful variation vibration due to imbalance of motor during operation. (2) Check if the motor is clean in itself and cleaned regularly. The environment of motor should be dry 61


and neat and there are not any sundries such as water, oil, and dust at the ambience of motor so as to avoid them from entering into the motor and damaging to it. (3) Check if the components of motor are in good order, e.g. if the frame, end cover, rotating shaft etc have breakage, bending and damage. (4) Check if the bearings are in good order. Shake the rotating shafts in the up and down and right and left directions to check if they have loosening and play. 6.5.4 Maintenance of Motor (1) Often keep the motor itself and its ambience clean to prevent water, oil, dust and other foreign substances from entering into it. (2) Often check the lubrication of bearings. Clean the bearings and bearing covers by kerosene before change of lubricating oil or grease. The filling volume of lubricating oil or grease should not exceed 70% of the internal volume of bearing. (3) Pay attention to the sound and vibration of all the parts of motor. If it is found out that there is any abnormity, the motor must be checked in time. (4) Check if the temperature rise of all the parts of motor is normal. (5) Check if the load-carrying current of motor exceeds the allowable value. 6.6 Brake 6.6.1 Type YWZ electrohydraulic shoe brake is as shown in Fig. 46.

Fig. 46 Type YWZ Electrohydraulic Shoe brake The characteristic of the normally engaged electrohydraulic brake: This brake has safe and reliable performance, smooth braking and high frequency of operation; the main hinges are provided with self-lubricating bearings, which have high transmission efficiency and long service; the brake has linings without asbestos and the brake shoes are of inserted mode and safe and reliable, and easy and quick to replace; the electriohydraulic thrustor to be fitted in the brake has good performance, complete functions, light weight and goodly appearance. The brake is provided with interlocked equal withdrawal distance device, braking torque scale device and manual releasing device. 6.6.2 The construction of type ED electrohydraulic thrustor is as shown in Fig. 47.

62


Fig. 47 Sketch of Construction of Type ED Electrohydraulic Thrustor 6.6.3 Maintenance of Brake Often check the performance of brake and abrasion of components and keep the brake lining surface clean to make the whole brake be operated freely, reliably and cleanly. The brake lining surface is not allowed to st ick grease or brake oil during operation and the linings should be regularly checked for thickness. 6.6.4 Discard of Brake Part The brake part should be discarded when one of the following conditions occurs: (1) Cracking; (2) The abrasion of brake friction lining reaches 50% of the original thickness; (3) The plastic deformation occurs in the spring; (4) The abrasion of little shaft or shaft hole diameter reaches 5% of the original diameter. See the product instruction manual accompanied with the crane for the details of purchased items. 6.7 Reducer 6.7.1

Type HQJ and Type HQJ-1 Reducers

Type HQJ and type HQJ-1 reducers belong in the standard series of lifting and handling machinary series reducers. Type HQJ reducers are ones with hardened tooth-surface and type HQJ-1 reducers are ones with medium-hardened tooth surface; The reducers of this kind have the features such as high load-carrying capacity, light weight, high efficiency, wide transmission parameter, varities of installation and assembly form etc., see Fig. 48.

63


Fig. 48 Construction of Reducer The installation form of reducer with three supporting points is as shown in Fig. 49:

Fig. 49 Sketch of Installation Form of Reducer A hole is provided on the joint surface of housing at the high speed end the stud is inserted into it and fixed on the front base. There are outer housings at both sides of low speed shaft, one is set as a fixed support and the other is set as a floating support. 6.7.2 Operation and maintenance of Reducer and Gear Pair 6.7.2.1 Maintenance and Check It must be guaranteed to often maintain and check if the bolts in every part are loose, if the lubricating oil in the gear box is within the scope of the specified value of oil scale, if the reducer is operated normally with load and if the oil leakage exists; Check the gears and shafts for abrasion regularly, the gears for meshing, the bearings for abrasion and lubricating oil for quality etc. Regular Lubrication: The oil used in the new reducers must be changed at intervals of two or three months at the earlier stage and should be done for the hoisting mechanism at intervals of six months and at yearly intervalsfor the traversing and traveling mechanisms later. All components must be cleaned by kerosene 64


when oil change and the impurities in the gearbox should be removed. EP industrial gear oils with different viscosities will be individually used in winter and summer and should be filled as per the specified value of oil scale. 6.7.2.2 Faults Occurring in Reducer and Fault Disposal The reducer should be handled in time when one of the following faults occurs: (1) Oil leakage Tighten up the connection bolts at all portions, change the disabled sealing member and the quantity of oil does not exceed the specified value of oil scale. The joint surface being recoated with seal gum: the disabled seal gum on the joint surface is removed (cleaned by 50% of acetic acid and 50% of gasoline, or acet and alcohol), dried up, evenly coated with seal gum as per the requirements, and then the reducer housings are closed after 3-5 minutes (for non-drying adhesive seal gum, the time may be longer), all the bolts are tightened and the reducer can be put into service after all the bolts have been tightened up after 24 hours. When the reducer housing is seriously distorted and the gap between joint surfaces is great, the reducer is lubricated by grease (molybdenum disulfide grease). The reducer is coated with grease after it has cleaned and dried up. (2) Vibration of reducer housing The cause is the bolts being not tightened up; the center line of driving shaft or driven shaft is not aligned with that of the connected component (motor, drum or wheel); and the base and support have insufficient rigidity. Check, adjust and tighten up the bolts, reinforce the base and support and addthe stop piece. (3) Noise and impact sound There is problem with machining and assembly precision. The both precisions should reach the Grade 8-8-7 specified in GB10095-88 when repair and change. Observe and judge the following when the reducer is running in without oil after assembly:

① Intermittent and silvery impact sound: There is any severe scar or adhesion on a certain tooth. Eliminate the adhesion and grind the scar by fine file or abrasive stick.

② Intermittent hoarse sound: There is not lubricating oil. The sound disappears after filling the lubricating oil.

③ Sharp whistle and impulsive sound: There are dirt pits on the ball in bearing race or the groove peels off. The bearing should be replaced if the impulsive sound is loud.

④ The noise is loud but even: The tooth tip gnaws at the dedendum. The tool angle is chamfered by fine file.

⑤ Uneven noise occurs: The central line of a pair of gears is disaligned, the angle of helical tooth is out-of-tolerance and the pyramidal face of tapered roller bearing is not pushed tightly (not adjusted tightly).

⑥ The initial contact line is one or more than two uniform lines around the pitch circle. The gears will reach the requirements gradually after running-in with load. (4) Heating of reducer housing (around the bearing) The reducer should not be used when the temperature rise exceeds 40% of the ambient air humidity and the absolute value exceeds 80%, check if the bearing is damaged, the gear or bearing oil is lack of oil, the loading time is too long, the rotation is locked and the tapered roller bearing is too tight. Adjust the reducer as according to the inspection result. 65


(5) Tooth fracture The strength is destroyed (overload in short time or quenching is too hard). If the bending fatigue fracture occurs (often check if there is any crack at the tooth root), the gear should be discarded. (6) Tooth abrasion The tooth abrasion is divided into running-in wear (the roughness of relative hard tooth surface should be small.) and grinding abrasion (clean the lubricating oil): For the hoisting mechanism in which the amount of wear of tooth in thickness reaches the original tooth thickness: if the gear at the first stage meshes 10% and the gear at other stages meshes 25% ( the half is taken for the main hoisting mechanism), and the gear at the first stage meshes 15% and the gear at other stages meshes 25% for the traversing and traveling mechanisms, the gear should be discarded. Pitting corrosion of tooth surface and local pitting corrosion (local uneven tooth surface): The contact stress concentration at the raised part leads to primary spots. Developmental pitting corrosion is because the tooth surface is too hard and has endurance crack under the repeating and oversize contact stress, the lubricating oil enters into the crack, the hydraulic pressure forces the crack to expand and forms chips. In this case, the pitting corrosion mostly occurs on the tooth surface of hardened brittle material. The material and heat treatment should confirm to the requirements specified on the drawing when the gears are paired. The gear should be replaced when the area of pitting corrosion exceeds 305 of the working surface and the depth of pitting corrosion exceeds 10% of the tooth thickness. (7) Teeth bonding together The pressure of tooth surface is big, there is not oil film and the tooth surfaces adhere each other. The gear should be repair in time at the initial stage , or otherwise it should be discarded. (8) Plastic deformation of tooth surface The local contact stress of tooth surface is oversize when low speed under the heavy load so that the convex and concave occur on the tooth surface with low hardness. The convex and concave should be filed smoot in time and the lubricating oil with high viscosity should be adapted. 6.8 Drum Assembly (Fig. 50) Type A. This type of drum assembly is composed of drum body, drum coupling, clip plate of wire rope (Fig. 51) and bearing block.

Fig. 50 Sketch A of Drum

66


Fig 51 Sketch of Clip Plate Assembly Type B. This type of drum assembly is composed by drum body, internal gear disc, clip plate of wire rope, bearing block etc. (for low lifting capacity and small diameter drum) (Fig. 52).

Fig. 52 Sketch B of Drum The drum is a durable component, but it should be often checked during operation if there is distortion and crack, if the clip plate bolts of wire rope are loose, if the bolts of drum coupling are loose, and if the wire rope and rope groove for abrasion and lubrication. Possible faults occurring in the drum: The rope groove is worn and the wire rope runs out of groove. The drum should be replaced when it can not control the wire rope arrangement in order because of rope groove abrasion. The drum should be discarded when one of the following situations occurs: (1) Cracking; (2) The abrasion of drum wall thickness reaches 20% of the original thickness. 6.9 Fixed Sheave Block Type A. The fixed sheave block is composed of rolled sheave (or cast sheave), rolling bearing, shaft and sheave seat. One-to-one lubricating oil holes for bearing are provided on the sheave shaft. (Fig. 53)

67


Fig. 53 Sketch A of Fixed Sheave Block Type B. The balance arm of wire rope is provided at its side. (Fig. 54)

Fig. 54 Sketch B of Fixed Sheave Block Attention must be paid to regular lubrication and inspection of sheave block during operation: The sheave groove should be clean and smooth without any damage to the wire rope. The sheave cover which prevents the wire rope out of sheave groove should be fixed firmly and reliably. The sheave should be replaced when one of the following situations occurs: (1) Cracking; (2) The uneven abrasion of sheave groove reaches 3mm; (3) The abrasion of sheave groove wall thickness reaches to 20% of the original thickness; (4) The bottom diameter of sheave groove reaches to 50% of the wire rope diameter because of abrasion; (5) Other faults that can damage to the wire rope. 6.10 Wheel Assembly See Fig. 55. The wheel, shaft and bearing box are assembled together for the convenience of installation and maintenance. The bearing boxes are divided into the anglar bearing box and 45° split type bearing box. When the wheel assembly is repaired, It had better to dismantle the whole wheel assembly and replace it with new wheel assembly that has been prepared in order to shorten the downtime and facilitate the wheel repair.

68


Fig. 55 Sketch of Wheel Assembly 6.10.1 Faults Occurring in Wheel Assembly (1) Peeling off occurs on the tread of wheel due to insufficienthardening depth. (2) The casting fault leads to the local pits of tread. (3) Abrasion, bruising due to gnawing and plastic deformation occur on the wheel flang. (4) The bearing is damaged due to improper assembling or poor lubrication (The lubricating grease does not enter into the bearing. It should be filled to 1/3 to 1/2 of the cavity of bearing by oil gun.). (5) The installation of rails is out of tolerance. 6.10.2 The wheel assembly should be discarded when one of the following situations: (1) The abrasion of tread exceeds 15% of the original thickness. (2) The abrasion of wheel flange exceeds 50% of the original thickness. (3) There is any faults such as dent, sand hole, shrinkage porosity, crack and flakes etc. on the tread of wheel. (4) The ellipticity reaches 1mm when the travel speed is lower than 50m/min and the ellipticity reaches 0.5mm when the travel speed is higher than 50m/min. 6.11 Coupling The shaft hole and key way of coupling should confirm to GB3852-83. During operation and maintenance of coupling, attention must be paid to: The alignment of two shafts that are connected by the coupling is very important to prolong the service life of coupling. When the coupling is lubricated, the tooth surface must be cleaned by gasolene before it is lubricated for the first time, and then is uniformly coated only with a thin layer of l ubricating grease after drying. When one of the following defects occurs, the coupling should be discarded: (1) Cracking; (2) Tooth fracture; (3) The abrasion of tooth thickness reaches 15% of the original tooth thickness for the hoisting mechanism and 20% for the traversing and traveling mechanisms. 6.11.1 Barrel-shaped Full Tooth and Half Tooth Couplings (GⅡCL and CLZ) The barrel-shaped tooth is that the external tooth is made to spherical face and the center of spherical face is on the axis of gear. It is composed of one (or two) barrel-shaped outer tooth sleeve(s) and one (or two) straight-tooth inner tooth ring(s). The coupling will transfer the torque by engaging of internal gear with 69


external gear and compensate the relative deviation of two transmission axial cord by axial swinging (referred to as azimuthal displacement) of the barrel-shaped outer tooth sleeve to the inner tooth ring of spur gear. The gear backlash is bigger than that of common gear. The bigger azimuthal displacement (relative to spur gear coupling) is permitted for the barrel-shaped tooth coupling so that this type of coupling can improve the contact condition of teeth. The half tooth coupling is composed of one internal gear ring, one external gear ring, shaft coupling and seal ring etc. (Fig. 56). The full tooth coupling is composed of two internal gear rings, two external gear rings and seal ring etc. (Fig. 57).

Fig. 56 Sketch of Half-Tooth Coupling

Fig. 57 Sketch of Full-Tooth Coupling 6.11.2 Gear Coupling of Brake wheel (NGCL and CLZ) The full coupling of brake wheel is composed of two internal gear rings, two external gear rings and brake wheel. (Fig. 58) The half-coupling of brake wheel is composed of one internal gear ring, one external gear ring and brake wheel. (Fig. 59) For the full-tooth coupling of brake wheel, the brake wheel and shaft coupling are connected with the external gear ring by key for the convenience of installation and repair of brake wheel. 70


Fig. 58 Full-Tooth Coupling of Brake wheel

Fig. 59 Half-Tooth Coupling of Brake wheel 6.11.3 Gear Coupling of Brake Disk The half-gear coupling of brake disk is composed of one internal gear ring, one external gear ring, one brake disk shaft coupling etc. (Fig. 60)

Fig. 60 Half-gear Coupling of Brake Disk 71


The full-tooth coupling of brake disk is composed of two internal gear rings, two external gear rings, brake disk etc. The brake wheel (disk) should be discarded when one of the following si tuations occurs: (1) Cracking; (2) For the brake wheels of hoisting and luffing mechanisms, the abrasion of flange reaches 40% of the original thickness; (3) For the brake wheels of other mechanisms, the abrasion of flange reaches 50% of the original thickness; (4) When the unevenness of wheel surface reaches to 1.5mm and if it can be repaired, the flange thickness after repair should meet the requirements in Items b and c above. 6.11.4 Drum Coupling The drum coupling is provided with the sphere with splined hole and its shell connecting flange has two parallel stopping faces, which is included between spheres with special key. The drum coupling can be subjected to very heavy radial load and transfer very big torque. It can be rotated flexibly and is very easy to assemble. The allowable deflection angle is 3°, which is very safe and reliable. (Fig. 61) The drum coupling can not compensate the axial displacement, so the drum bearing block must be relieved from the axial constraint. ＞3mm clearance must be kept at both ends of bearing. For the drum coupling, it should be often checked if the fastening bolts of reducer output end and the connection bolts between the coupling and the drum are loose. The drum coupling should be filled with grease for lubrication at monthly intervals. When filling lubrication, all the holes should be filled with grease in turn. The grease filling pressure should be more than 20Mpa. The filler holes must be located below until the grease overflows from the sphere.

Fig. 61 External View of Spherical Hinge Type Drum Coupling 6.11.5 Cross-axle Universal Coupling The SWF series cross-axle universal coupling is fitted with thrust bearings at its four ends and has long service life. The connection bolts should be put in from the side of connected flange. The bulged stop hole of connected flange should be matched by c8. The end surface key should be matched by H8. (See Fig. 62 and Fig. 63) The connecting bolts must be often checked for fastening and tightened up according to a specific pre-tightening torque. Grease should be filled to each bearing for lubrication at monthly intervals.

72


Fig. 62 External View of Cross-axle Universal Coupling

Fig. 63 Sketch of Cross-axle Universal Coupling 6.12 Hook Block The hook block consiss of hook, hook crossbar, hook nut, rolled sheave and yoke plate. (Fig. 64). During operation of hook block, it should be often checked if the hook nut and slack-preventing device are loose or not; if any crack exists at the undercut between the bottom diameter of tail screw of hook and the rod. If any, the hook should be timely changed. It should be checked if the mouth of hook for any abrasion. The load being lifted by canting pull is forbidden. The limit switches are checked for normality in order to prevent the sheave block from being out of the upper limit, thus resulting in damage. The bearings are regularly filled with grease for lubrication, especially lubrication of thrust bearings.

Fig. 64 Hook Block 73


When one of the following situations appears on the hook, the hook should be discarded: (1) Cracks. If any defect is found out on the hook, it cannot be repaired; (2) Abrasion of dangerous section reaches 10% of t he original size; (3) The degree of opening of hook is added by 15% compared to the original size; (4) Torsional deformation is over 10°; (5) Plastic deformation occurs at the dangerous section or at the neck of hook. 6.13 Lifting Load Limiter (Fig. 65) and Electronic Scale

Fig. 65 Lifting Load Limiter 6.13.1 Basic Requirements The lifting load limiters should comply with GB12602－90 ‘Technical Rules for Safety of Overload Protective devices for Hoisting Machinery’. They have the functions of acoustic-optical alarming, digital display of lifting capacity and disconnecting the power supply to lifting circuit of crane. Requirements for lifting load limiters: (1) Integrated precision of system ：＜5％F.S (2) Setting of alarm points ： Pre-alarm point：90% of the rated lifting capacity Overload alarm point: 105% of the rated lifting capacity Immediate alarm point: 130% of the rated lifting capacity (3) Overload capability of sensor: over 200% of the rated lifting capacity (4) Protection class of sensor: IP65 (5) Protection class of meters: IP54 After the lifting load limiters have been installed in the crane, they should be adjusted and calibrated according to their performance and precision. 6.13.2 The standard sensors are used for the electronic scale and lifting load limiter (Fig. 66, Fig. 67 and Table 25) Table 25 Main Technical Parameters of Sensor

74


Fig. 66 Sketch of Sensor

Fig. 67 Appearance of Sensor

6.13.3 Installation of Sensor (1) The sensor is located under the bearing block of drum (Fig. 68)

Fig. 68 Sketch of Installation of Sensor of Drum Assembly (2) The sensor is located under the shaft of fixed sheave (Fig. 69)

75


Fig. 69 Sketch of Installation of Sensor of Fixed Sheave Block The connection of sensor, meter and electronic scale with large screen indicator which are located under the fixed sheave is as shown in Fig. 70:

Fig. 70 Sketch of Connection of Weighing System 6.13.4 Operation and Maintenance (1) During storage of overhead traveling crane, the sensors must be protected against solarization, rain, corrosion and collision, and the crane being lifted at the place where the sensor is installed is forbidden. (2) The sensors should be re-adjusted and leveled after installation and before operation,. And they should be calibrated regularly. (3) All the parts of sensor must be carefully checked by the operator at each shift for reliability and the digital display is normal when the load to be lifted is set. (4) The sensor will fail or be damaged if it got seriously collision. After it is replaced with a new one, the sensor must be adjusted level and the bolts can be tightened up only after adjusting. Special attention must be paid to elimination of additional force that affects the measuring precision of sensor and is applied on the sensor. After that, it can be reconnected, adjusted and calibrated. (5) When the crane is tested with static load and dynamic load, the lifting load limiter should be in an out-of-service state.

76


6.14 High Temperature Air Fan (See Fig. 71)

Fig. 71 Sketch of Entirety Type Air Fan (Flange-mounted for Air Supply Return at Bottom) The entirety type air fan is as shown in Fig. 71. It consists of fully enclosed compressor, L-type bridge type nest plate condenser, straightly drawing type axial flow fan, evaporator, built-in centrifugal fan, inlet expansion valve, reservoir, dry filter, high and low pressure relay, pressure meter and electric control box. The mode of air supply is that of air supply at bottom which is used for this crane. The cool air is fed to the electrical room through an air pipe at the bottom. The cooling fan is installed on the cover plate of main girder. The air supply interface, air return interface and air pipe which have been manufactured by the crane manufacturer are installed according to the attached drawings. The split type cooling fan (Fig. 72) is divided into two bodies, i.e. the outdoor machine and indoor machine, between which the liquid pipe and air pipe are connected. The outdoor machine is installed in the ventilated place and the indoor machine is installed in the electrical room or operator’s cabin. The temperature inside the room that is cooled by the fan can be kept at about 18 ℃～30℃.

77


Fig. 72 External View of Split Type Cooling Fan The cooling fans should be maintained according to the instruction manual accompanied with the crane. During operation, it must be often checked if the filter screens are blocked; if the high voltage, low voltage and motor overcurrent protective devices are operated normally and if the connection of pipeline is normal. The trouble is found out, it should be timely removed. 6.15 Buffer 6.15.1 Spring Buffer The spring buffers are divided into base-welded type spring buffer (Fig. 73), shell-welded type spring buffer and end mounted type spring buffer. The buffers which have been well assembled and the buffer stops (or stop rod) should be compressed and reset flexibly and smoothly. During operation, attention should be paid to any crack on the shell of buffer and the connecting bolts are checked for loosening.

Fig. 73 Spring Buffer 6.15.2 Polyurethane Buffer (Fig. 74) The polyurethane buffer has small volume, light weight and convenient installation. Pay attention to the tightness of connecting bolts during operation.

Fig. 74 Polyurethane Buffer 6.15.3 Hydraulic Buffer The hydraulic buffer (Fig. 75) has high capacity, high cushinring and high efficiency of dissipation. Most 78


of the external impacting energy is dissipated in the buffer. The buffer must be installed according to the direction indicated on the base board during installation. and the hydraulic oil to be used should be wear resistant hydraulic oil whose number is not below 20#. Pay attention to checking the connecting bolts for loosening during operation.

Fig. 75 Hydraulic Buffer 6.15.4 Elaxtic Rubber Buffer (Fig. 76)

Fig. 76 Elaxtic Rubber Buffer The elaxtic rubber buffer (Fig. 76) takes the elaxtic rubber that has been specially allotted as its working medium and utilizes its capacity of viscous damping and full deformation to complete absorption of impact energy and restoring to the initial state. It has small space usage and light weight. It should be often checked if the head of buffer can come back to its original position after compression during operation. There should be no blocking. The connecting bolts should be checked for loosening.

6.16 Cable Carrier The towing arm on the bridge conductive frame is inserted into the towing carrier to drive it to run on the I-beam of bridge to realize power supply to the trolley, see Fig. 77. It must be often checked if the cable carriers are running normally, I-beam is deformed and the traction rope is knotted during operation. It should be noted that the bearings are regularly coated with grease. If the trouble is found out, it must be timely removed and the carrier is changed if it is damaged. 79


Fig. 55 Sketch of Wheel Assembly 6.10.1 Faults Occurring in Wheel Assembly (1) Peeling off occurs on the tread of wheel due to insufficienthardening depth. (2) The casting fault leads to the local pits of tread. (3) Abrasion, bruising due to gnawing and plastic deformation occur on the wheel flang. (4) The bearing is damaged due to improper assembling or poor lubrication (The lubricating grease does not enter into the bearing. It should be filled to 1/3 to 1/2 of the cavity of bearing by oil gun.). (5) The installation of rails is out of tolerance. 6.10.2 The wheel assembly should be discarded when one of the following situations: (1) The abrasion of tread exceeds 15% of the original thickness. (2) The abrasion of wheel flange exceeds 50% of the original thickness. (3) There is any faults such as dent, sand hole, shrinkage porosity, crack and flakes etc. on the tread of wheel. (4) The ellipticity reaches 1mm when the travel speed is lower than 50m/min and the ellipticity reaches 0.5mm when the travel speed is higher than 50m/min. 6.11 Coupling The shaft hole and key way of coupling should confirm to GB3852-83. During operation and maintenance of coupling, attention must be paid to: The alignment of two shafts that are connected by the coupling is very important to prolong the service life of coupling. When the coupling is lubricated, the tooth surface must be cleaned by gasolene before it is lubricated for the first time, and then is uniformly coated only with a thin layer of l ubricating grease after drying. When one of the following defects occurs, the coupling should be discarded: (1) Cracking; (2) Tooth fracture; (3) The abrasion of tooth thickness reaches 15% of the original tooth thickness for the hoisting mechanism and 20% for the traversing and traveling mechanisms. 6.11.1 Barrel-shaped Full Tooth and Half Tooth Couplings (GⅡCL and CLZ) The barrel-shaped tooth is that the external tooth is made to spherical face and the center of spherical face is on the axis of gear. It is composed of one (or two) barrel-shaped outer tooth sleeve(s) and one (or two) straight-tooth inner tooth ring(s). The coupling will transfer the torque by engaging of internal gear with 69


external gear and compensate the relative deviation of two transmission axial cord by axial swinging (referred to as azimuthal displacement) of the barrel-shaped outer tooth sleeve to the inner tooth ring of spur gear. The gear backlash is bigger than that of common gear. The bigger azimuthal displacement (relative to spur gear coupling) is permitted for the barrel-shaped tooth coupling so that this type of coupling can improve the contact condition of teeth. The half tooth coupling is composed of one internal gear ring, one external gear ring, shaft coupling and seal ring etc. (Fig. 56). The full tooth coupling is composed of two internal gear rings, two external gear rings and seal ring etc. (Fig. 57).

Fig. 56 Sketch of Half-Tooth Coupling

Fig. 57 Sketch of Full-Tooth Coupling 6.11.2 Gear Coupling of Brake wheel (NGCL and CLZ) The full coupling of brake wheel is composed of two internal gear rings, two external gear rings and brake wheel. (Fig. 58) The half-coupling of brake wheel is composed of one internal gear ring, one external gear ring and brake wheel. (Fig. 59) For the full-tooth coupling of brake wheel, the brake wheel and shaft coupling are connected with the external gear ring by key for the convenience of installation and repair of brake wheel. 70


Fig. 58 Full-Tooth Coupling of Brake wheel

Fig. 59 Half-Tooth Coupling of Brake wheel 6.11.3 Gear Coupling of Brake Disk The half-gear coupling of brake disk is composed of one internal gear ring, one external gear ring, one brake disk shaft coupling etc. (Fig. 60)

Fig. 60 Half-gear Coupling of Brake Disk 71


The full-tooth coupling of brake disk is composed of two internal gear rings, two external gear rings, brake disk etc. The brake wheel (disk) should be discarded when one of the following si tuations occurs: (1) Cracking; (2) For the brake wheels of hoisting and luffing mechanisms, the abrasion of flange reaches 40% of the original thickness; (3) For the brake wheels of other mechanisms, the abrasion of flange reaches 50% of the original thickness; (4) When the unevenness of wheel surface reaches to 1.5mm and if it can be repaired, the flange thickness after repair should meet the requirements in Items b and c above. 6.11.4 Drum Coupling The drum coupling is provided with the sphere with splined hole and its shell connecting flange has two parallel stopping faces, which is included between spheres with special key. The drum coupling can be subjected to very heavy radial load and transfer very big torque. It can be rotated flexibly and is very easy to assemble. The allowable deflection angle is 3°, which is very safe and reliable. (Fig. 61) The drum coupling can not compensate the axial displacement, so the drum bearing block must be relieved from the axial constraint. ＞3mm clearance must be kept at both ends of bearing. For the drum coupling, it should be often checked if the fastening bolts of reducer output end and the connection bolts between the coupling and the drum are loose. The drum coupling should be filled with grease for lubrication at monthly intervals. When filling lubrication, all the holes should be filled with grease in turn. The grease filling pressure should be more than 20Mpa. The filler holes must be located below until the grease overflows from the sphere.

Fig. 61 External View of Spherical Hinge Type Drum Coupling 6.11.5 Cross-axle Universal Coupling The SWF series cross-axle universal coupling is fitted with thrust bearings at its four ends and has long service life. The connection bolts should be put in from the side of connected flange. The bulged stop hole of connected flange should be matched by c8. The end surface key should be matched by H8. (See Fig. 62 and Fig. 63) The connecting bolts must be often checked for fastening and tightened up according to a specific pre-tightening torque. Grease should be filled to each bearing for lubrication at monthly intervals.

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Fig. 62 External View of Cross-axle Universal Coupling

Fig. 63 Sketch of Cross-axle Universal Coupling 6.12 Hook Block The hook block consiss of hook, hook crossbar, hook nut, rolled sheave and yoke plate. (Fig. 64). During operation of hook block, it should be often checked if the hook nut and slack-preventing device are loose or not; if any crack exists at the undercut between the bottom diameter of tail screw of hook and the rod. If any, the hook should be timely changed. It should be checked if the mouth of hook for any abrasion. The load being lifted by canting pull is forbidden. The limit switches are checked for normality in order to prevent the sheave block from being out of the upper limit, thus resulting in damage. The bearings are regularly filled with grease for lubrication, especially lubrication of thrust bearings.

Fig. 64 Hook Block 73


When one of the following situations appears on the hook, the hook should be discarded: (1) Cracks. If any defect is found out on the hook, it cannot be repaired; (2) Abrasion of dangerous section reaches 10% of t he original size; (3) The degree of opening of hook is added by 15% compared to the original size; (4) Torsional deformation is over 10°; (5) Plastic deformation occurs at the dangerous section or at the neck of hook. 6.13 Lifting Load Limiter (Fig. 65) and Electronic Scale

Fig. 65 Lifting Load Limiter 6.13.1 Basic Requirements The lifting load limiters should comply with GB12602－90 ‘Technical Rules for Safety of Overload Protective devices for Hoisting Machinery’. They have the functions of acoustic-optical alarming, digital display of lifting capacity and disconnecting the power supply to lifting circuit of crane. Requirements for lifting load limiters: (1) Integrated precision of system ：＜5％F.S (2) Setting of alarm points ： Pre-alarm point：90% of the rated lifting capacity Overload alarm point: 105% of the rated lifting capacity Immediate alarm point: 130% of the rated lifting capacity (3) Overload capability of sensor: over 200% of the rated lifting capacity (4) Protection class of sensor: IP65 (5) Protection class of meters: IP54 After the lifting load limiters have been installed in the crane, they should be adjusted and calibrated according to their performance and precision. 6.13.2 The standard sensors are used for the electronic scale and lifting load limiter (Fig. 66, Fig. 67 and Table 25) Table 25 Main Technical Parameters of Sensor

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11# EOT Crane Operation Manual

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