Fishing Operations (Best Practices)

CUT & THREAD FISHING PROCEDURES AND BEST PRACTICES Version 2005Jan15

Schlumberger Private

Schlumberger Schlumberger

A CUT & THREAD FISHING OPERATION is the most dangerous operation involving wireline. Prior to starting a cut & thread operation ensure the following is completed: A written HARC is completed and discussed with all involved This “CUT & THREAD” procedure is reviewed with all involved The operation involves several companies, including the operating company, the rig company, the fishing hand and Schlumberger. It is an integrated effort with one supervisor, the Operator Wellsite Supervisor. Communication is critical for a safe & successful fishing job EVERYONE INVOLVED IS EMPOWERED TO STOP THE OPERATION IF THEY FEEL IT IS UNSAFE!!

1 Hang Sheave In Derrick Try to hang sheave with fishing sling so it will not interfere with the handling of drillpipe Lower sheave must be moved away from rotary to prevent interference with rig floor operations and cable contact with top drive Clear the rig floor while derrick man hangs the sheave.

Use Longest Links Available


In order to determine the proper fishing assembly to use, the derrick man should provide a best estimate of the distance available between the top of pipe and the sheave.

Top Drive

108” ones are standard; try to use 140” ones or longer Top Drive

Inspect every 5,000’ and before going into open hole for cable wear, damage of fishing equipment, and tightness of fishing equipment If available, install roller assembly on top drive to eliminate cable rubbing; If one is not available, have rig make one

108” >108”

Do not use the Varco Wireline Adapter commonly known as “Bicycle Wheels” Not Desirable

Desirable

Tension Device Switch to TDK if using CMTD ( if available) (Prevents cable backlash)

CMTD Schlumberger

Compare TDK and CMTD readings so that fishing operation is performed under correct tension Do not pre-load lower sheave with air hoist tension; Sheave should hang freely until weight is applied

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TDK

the Cable 2 Cut Pull 1,000 to 2,000 lbs over normal tension and secure T-Bar cable clamp to cable If hole is straight, cut cable 5 to 7 feet above rotary table

Cable

If hole is deviated, cut cable 10 feet above rotary table plus 1 foot for every 1,000 feet greater than 10,000 feet T-Bar

T-Bar

Test T-Bar for slippage before cutting cable Tapered Cone

Use tapered cones from LEH-Q on top of fishing weights If available, use heavier-shorter fishing weights with knuckle joints and swivel, or Wire Rope Weight with Cooper Knuckle-Swivel (a must on top drives!!) Minimum restrictions for all drilling hardware (jars, drill collars, and heavy weight) must be known to determine size of overshot guide to use Always use the largest guide that will fit through drilling hardware

Highly Recommended

Rig Up Spearhead Overshot O r


Use proper size cable bushing in T-Bar and mark cable to ensure there is no slippage

Or

Knuckle Joints

Cooper Knuckle -Swivel

Never use “after-market” non-SLB rope sockets. Swivel used to prevent cable torque from backing off spear assembly.

Overshot Guide

Rig Up Spear Never use spears which contain “W’s” in their work order numbers Always use Hexagon Adapter when stripping over; Hexagon Adapter will stop on top of no-go if dropped accidentally Only use plain adapter when drill pipe ID is too small for Hexagon Adapter and switch back to Hexagon Adapter as soon as drill pipe ID permits Never use “after-market” non- SLB rope sockets

Work Order Number Stamped Here

Hexagon Adapter

If basket type grapple is used, assemble 5-3/4” overshot, basket grapple, and no-go

Bowl to Top Sub 5 3/4” 7600

4 11/16” 3200

4 11/16”

Assemble 4-11/16” overshot, spiral type grapple, and no-go (preferred method)

Make-Up Torque

5 3/4”

3 Assemble Overshot

Not Desirable

Desirable

Bowl to Guide 5 3/4” 4 11/16” 1700 1300

ALWAYS VISUALLY INSPECT grapple for proper size for job and NEVER install a used grapple

Remove hex adapter, pass well end of cable through downhole overshot and reinstall hex adapter (Remember, 2 1/4” hex adapter will not pass through the smaller ID no-go)

Install Drain Sub Drain sub with blow out disk aids in grapple cleaning and prevents pulling wet drillpipe after disk is blown Install above downhole overshot assembly

Blow Out Disk


Thread Cable Thru Overshot

4 Thread Through Slowly ( <2000 FPH) pull overshot assembly to derrick man to thread through bottom hole assembly Communication is critical at this point to prevent pulling assembly into the sheave!! Use radios!! Clear rig floor!! Make sure all minimum restrictions are known in pipe Flag line at winch after bottom of assembly reaches the the top of pipe. This flag may need to be adjusted in Step 5 when full stands of pipe are used.

First Stand of Drillpipe, Collars, or Heavy Weight


DO NOT EXCEED THIS FLAG WITHOUT 1st STOPPING THE OPERATION, YOU WILL PULL INTO THE SHEAVE!!!

Remove T-Bar Tighten overshot to bottom of first stand of drillpipe Stab spearhead overshot, pull cable tension, check for slippage, and remove T-bar cable clamp after completing check Remove IDW and position spooling arm to one side (If CMTD is used, do not remove)

Tightened Overshot Assembly

Cable Tension= 1000 lbs to 2,000 lbs + Normal

Spear Stabbed into Overshot

T-Bar

When Slips Are Set After the slips are set, floorhand should position elevators away from spearhead assembly until elevators are clear of assembly. If not done, elevators could catch hex adapter and cause cable to break Afterwards, install C-plate, slack off cable, and release overshot with special tongs

Use correct C-plate for pipe size Schlumberger

4 1/2 IF

3 1/2 IF

C-Plate Location

5 Flag Line After tripping in with drill collars, jars, and heavy weights, flag line at drum and bottom sheave with rags, tape, paint, etc... when spearhead overshot is positioned over drillpipe by the derrick man. Derrick man will thread overshot assembly through drillpipe.

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Flag Line Again Flag line again at drum and bottom sheave when spear is stabbed in spearhead overshot ONCE FLAGS ARE SET, DO NOT EXCEED WITHOUT 1ST SHUTTING DOWN OPERATIONS AND DISCUSSING WITH ALL !! YOU WILL PULL INTO THE SHEAVE!!

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Trip In Slowly Maintain Proper Cable Tension (1,000 to 2,000 lbs plus normal) Pay particular attention to top drive / block; If weights are in danger of hanging up top drive, slack off slightly. but do so carefully. Pull back to 1-2K lbs over once the weights are clear.

Drillpipe


ONCE FLAGS ARE SET, DO NOT EXCEED WITHOUT 1ST SHUTTING DOWN OPERATIONS AND DISCUSSING WITH ALL !!

6 Re-thread Overshot Pull overshot to derrick man who will thread through another stand of drillpipe (watch flag at at drum)

Stab Overshot


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Drillpipe

Attach drain sub to second stand of drillpipe Position pipe over spearhead overshot and slack off until “the other flag ” on the drum is reached Schlumberger

Keep hands in safe position

Hands

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C-Plate

Make Overshot Connection Make overshot connection, pull enough tension to remove C-plate, and adjust tension again to normal plus 1,000 lbs to 2,000 lbs.

Too low of tension will result in cable being damaged or completely cut by the overshot assembly as it moves downward. NOW YOU HAVE A CABLE FISHING JOB ON YOUR HANDS!!!! C-Plate

7 Make-Up Drillpipe Drillpipe is made-up and tightened Slips are pulled and the descent begins Do not rotate pipe in hole Observe tension, if it increases stop & discuss

Slips

1

2

Repeat procedure for each stand of drillpipe until circulation depth is reached

Set Slips and Disconnect Overshot

If excessive open hole is present, circulation every 10 stands (especially if lost circulation material is used) should be considered to keep grapple clean

Trip in Slowly

Remember to watch your speed!!!! Going in the hole slowly is the only way If crew changes, STOP… review HARC & Fishing procedure before proceeding

3 Rethread Overshot Through Drillpipe

4

5

Stab Overshot

Make Overshot Connection

Remove C-Plate

Then Make-Up Drill Pipe C-Plate


Tripping in Hole

8 Install Circulating Sub Install sub one stand above fish Kelly or Top Drive Spearhead Overshot

Circulating Sub Circulating Basket Spearhead Sub

Circulating Sub

Never put circulating sub in hole

Circulate One Stand Above Fish Cuttings and debris should be removed from downhole overshot assembly by circulation of mud at a one stand maximum Only circulate long enough to ensure grapple is clean Never circulate too long or too fast; cable damage will occur

Engage Fish Maintain normal tension plus 1,000 to 2,000 lbs and approach fish slowly; Observe tension and set at least 2,000 additional pounds on fish; Pull at least 2 joints of drillpipe (60’) and observe tension A minimum tension loss of 2,000 lbs should be observed to confirm latch (a tension resulting in 0 after pulling pipe would be a definite indication of engagement) Repeat this engagement procedure at least twice If tension does not decrease, the fish in not engaged DO NOT ROTATE PIPE AFTER ENGAGING FISH!!!


C-Plate

9 Blow Drain Sub Disk

Drain Sub

Apply mud pump pressure to blow disk in sub Pump slug; especially for oil base mud (Do not trip out with oil base wet string; it’s unsafe) Afterwards, repeat engagement process before breaking weak point to make sure tool was not pumped out of the overshot

Reconfirm Engagement Repeat engagement process at least twice to ensure tool is still in downhole overshot Again, observe tension and set at least 2,000 additional pounds on fish; Pull at least 2 joints of drillpipe (60’) and observe tension A minimum tension loss of 2,000 lbs should be observed to confirm latch (a tension resulting in 0 after pulling pipe would be a definite indication of engagement)

Break Weak Point Install T-Bar and calculate cable stretch required to break weak point (Depth) X (Stretch Coefficient)

Move cable up and down within stretch limit with block to work tension to weak point Use block to break weak point and record tension at which break occurs Make sure rig floor is clear and inspect lower sheave chain before proceeding


Blown Disk

10 Install TIW Valve

Logging Cable

Install TIW valve before spooling cable onto drum This could aid in controlling well if trouble occurs

TIW Valve

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Tie Square Knot Cut off rope sockets on both well end and unit end of cable

Tie square knot in cable, pull tight , and tape ends

To Well

To Logging Unit

Square knots reduce cable breaking strength by 50%!! Consult In-Touch on High Tension jobs!! Don't pull tension on a square knot above 25% of the cable break strength. In that case use two T-bar method to get the knot to the drum plus at least three wraps before pulling.

Spool Cable Observe square knot as it goes over upper and lower sheaves

Afterwards, reinstall IDW to measure cable Schlumberger

Do not pull the weakpoint assembly over the sheave!! Clear rig floor when near surface Schlumberger

Square Knot


OPTIONAL

11 Tripping Out of Hole Do not rotate pipe while tripping out of hole; Rotation may cause fish to disengage and fall out of downhole overshot DO NOT ROTATE DRILLPIPE!!! Drillpipe


At Surface Install make-up plate at first available tool collar and remove overshot assembly

Downhole Overshot With Fished Tool

Remove remaining toolstring with air hoist, cover hole, and finish breaking and cleaning tools in rat hole Make-up Plate

Make sure air hoist is rated for toolstring

Removing Fish

Grapple

Remove guide and bump tool vertically against rig floor to free grapple control

Spin tool and grapple out of overshot by turning in a clockwise motion (Tool should come free without applying excessive force) If another method is used to release tool, remove electronics from housing in overshot to minimize damage

Grapple Control

Guide Shoe

12 Reverse Cut and Thread Provides an alternative to breaking the weak point after the tool string has been engaged in the grapple. USE THIS TECHNIQUE IF: a) The weakpoint can not be safely broken due to deviation and doglegs b) If you want the cable to remain attached to the toolstring until it reaches the casing or surface (normally when fishing with RA sources) c) If you suspect the rubber boot on the top of bridle is wedged inside the grapple (when fishing with logging bridles) impeccable

- Safest and most reliable fishing technique - Only one cable clamp is needed - Cable tension can be continuously monitored. If the fish is pulled out of the grapple, you can see the tension increase and act promptly. - The disadvantage is that the procedure is relatively slow and requires a lot of coordinatingwith the derrick man.

Method2: Dual T-Bar method - Not a recommended procedure - No longer have control over the down hole tension of the cable. - Need too feed a lot of slack into the pipe. - Should the fish fall out of the grapple and become stuck, excessive tension may either strip the cable out of the cable clamp or break the weak point. - To use this method you must be 100% sure that the tool is properly engaged in the grapple.


Method1: Single T-Bar and Reef Knot method

13 Single T-Bar and Reef Knot method Cut Spear and Overshot Break the last stand and put a T-Bar on the cable and slack until spear,overshot, and weights are out Cut off the spear,overshot and weights on both end of cable

Remove cable from Drill Pipe Re-attach one weight bar and pull the cable out of the drill pipe with help from derickman. Lower the cable once it is out of the drill pipe NOTE: - Need at least 1 weight bar as counter weight so that cable will not slip from the top sheave - Better to pull the cable by hand instead of using winch for better control (reduce chances of weight bar knocking the top sheave)

Tie Square Knot Remove the weight bar from the uphole end of the cable. Tie square knot in cable, pull tight, and tape ends.

NOTE: Make sure the tails of the knot is long enough and and properly taped to avoid the knot from coming loose.

Remove


Cut

14 Reversing out Pull up with the winch until the knot is tight NOTE: Clear the rig floor when picking up the cable. In case the knot unravels, the cable will come out through the upper sheave and fall on the rig floor

Make sure knot is tight

Remove the T-Bar and slack down until the knot is inside the drill pipe Schlumberger Private

Driller will pull up the drillpipe and break the next connection.

Remove cable from Drill Pipe Have the driller pull up the drill pipe Pull the wireline cable up 90ft/30m (or depending on the length of the drillpipe connection) Slack off the cable until the knot is out of the pipe

Cut both ends of the cable

Cut

Continue Reversing out Re-attach one weight bar and pull the cable out of the drill pipe with help from derickman. Lower the cable once it is out of the drill pipe Remove the weight bar. Tie a square knot and keep doing this until the bottom of the fish is in the casing shoe or the tool is at surface You can proceed with breaking the weakpoint by following the previous instructions.

15 Dual T-Bar method Cut Spear and Overshot Break the last stand and put a T-Bar on the cable and slack until spear,overshot, and weights are out Cut off the cable on the downhole end. Release the spear from the overshot using the special thong Schlumberger Private

Cut

Remove cable from Drill Pipe Pull the cable out of the drill pipe with help from derickman. Lower the cable once it is out of the drill pipe Secure the uphole end of the cable since it will not be used for now NOTE: - Better to pull the cable by hand instead of using winch for better control (reduce chances of weight bar knocking the top sheave)

Preparing the T-Bar Connect slings to the T-Bar handle and attach the sling to the rig air tugger Have the Driller pick up the drill pipe, and pick up the slack on the air tugger as well along with the drill pipe

Air Tugger

Slings

16 Installing 2nd T-Bar Have the Driller break the connection, and then pick up the drill pipe just enough to install the 2nd T-Bar Make sure the air tugger is holding the top T-Bar firmly NOTE: Be careful not to pick up too much. If not you can break the weakpoint

Clear the rig floor of all unnecessary personnel Have the derickman slowly loosen up the top T-bar. The cable should slide down from inside the drill pipe If the cable not coming out, the operator needs to pull the cable out by using a long hook. Make sure he is at a safe distance before pulling out the cable.

Pulling Out Pipe Lower down the top T-Bar using the air tugger Rat back the drill pipe into the derrick Cut the cable close to the lower T-Bar Continue doing this until the bottom of the fish is in the casing shoe or the tool is at surface You can proceed with breaking the weakpoint by following the previous instructions. Cut


Removing Cable from Top T-Bar

When Things Go Wrong Spearhead Cable Shortens During Descent

Figure 1

New Length Original Length

Figure 2 Option two involves cutting the cable below the spearhead and adding extra cable by building two new rope sockets and using a double ended torpedo (Fig. 3). After this extra length is added, the spearhead is reinstalled and tested.


If cable cutting length calculations are incorrect at the beginning of the job, the spearhead will move closer to the rig floor as the downhole overshot approaches the fish. This can be a real problem with highly deviated and dog-legged wells. During the descent, cable is pulled off the wall reducing its original length. Normal tension also increases to keep the spearhead assembly at the same distance above the rig floor. This is similar to holding a rope and applying a force in the center to cause a deflection. As the deflection increases, the rope’s length decreases (Fig. 1). When this reaches an unacceptable level where the C-plate can’t be applied, the operation will come to a halt (Fig. 2). One option to solve this problem is to install an extension below the spearhead to increase the distance from the rig floor.

When Things Go Wrong Continued….. Spearhead Assembly

Spearhead Assembly

Rope Socket Housing Extension Double Ended Torpedo

Option #2

Option #1

Figure 3

There is a slight possibility that too much cable may be added using these options. When this happens, slacking off on the cable becomes a reality whenever the C-plate is removed or installed and can cause cable damage if not performed correctly (Fig. 4). Slacking when the pipe is motionless is fine and should not cause any problems as long as it is removed and the correct tension regained before the pipe is moved. Figure 4


Rope Socket Housing

When Things Go Wrong Continued….. Cable Breaks While Breaking Weak Point •Since the fish is already in the grapple, the cable can located by tripping out pipe. Once the other end is recovered, the T-bar can be reinstalled and the cable pulled again as before.

Dropped Spearhead Assembly •If the spearhead with rope socket and cable is accidentally dropped into the pipe, run the cable overshot with the largest applicable guide down the pipe and attempt to engage the spear. It should only be a few hundred feet below the rotary. •If this fails, have the drill pipe pulled and retrieve the spearhead. The no-go in the downhole overshot should catch the hex adapter.

Can’t Confirm Engagement There are four major reasons why tool engagement can not be confirmed. They are: •Inoperative or malfunctioning tension device Confirm Tension Device is working correctly •Debris in the downhole overshot An overshot full of debris can prevent the grapple from engaging the fish. The only way to clear it is by circulating. If circulation does not solve the problem, one of the other conditions may exist. •Slack in the cable Slack in the cable during a fishing job can produce a large coiled “wad” inside the downhole overshot preventing engagement (Fig. 4). This is why maintaining the proper tension throughout the operation is so important. •Wrong size grapple If the wrong size grapple is used, there is still a slight chance that the tool can be retrieved. Grapples operate in a range and can expand a little more than indicated to accept a slightly larger fish.


•Proper tension must be maintained throughout the entire fishing operation. Slack cable can cause broken armors and weak spots in the cable. With slack in the hole, the cable can double back around the guide and get cut. At the very least, this could produce a weak spot and unfavorable results when attempting to break the weak point.

Fishing Operations (Best Practices)

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