A PROJECT REPORT ON
Modification of Manual Plate Bending Machine FOR PARTIAL FULFILLMENT OF THE REQUIREMENT FOR THE AWARD OF DEGREE IN BACHELOR OF ENGINEERING IN MECHANICAL ENGINEERING
GUIDED BY PROF. JAYANT CHAUDHARI.
SUBMITTED BY MR. PRATIK P. JADHAV. MR. SWAPNIL S. PATIL. MR. ABHIJIT S. BHOSLE. MR. SHAILESH Y. SINGH.
DEPARTMENT OF MECHANICAL ENGINEERING
SARASWATI EDUCATION SOCIETY’S GROUP OF INSTITUTIONS FACULTY OF ENGINEERING DIKSAL, TAL. KARJAT, DIST. RAIGAD, MAHARASHTRA 2015-16
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ABSTRACT
We feel pleasure & proud to present VII semester project report. Our project “Modification of Manual Plate Bending Machine” is to eliminate the pre-bending process and time required in
loading and unloading from hydraulic press. This concept of introducing double pinching would be competent advice received from “SHREYAS INDUSTRIES”, for continuous activity. However, we believe that bending, rolling is a complex and difficult process where the theoretical knowledge must be reflected in the practice and execution. “SHREYAS INDUSTRIES” Girgaon, Mumbai, Maharashtra, India 400 004 deals basically in specialized fabrication and trading of various products related to engineering industries. Also it deals with manufacturing of various casings and trading of them. Various manufacturing processes done in factory are: · Sheet Metal Cutting · Sheet Metal Bending · Pipe Cutting and Bending · Plate Bending and Rolling · Various Welding Process Factory is equipped with modern facilities like CNC Plasma Cutting Machine, NC, Rolling Machine, CNC Lathe and Milling Machines, all products manufactured, design and comply with the international standards.
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CONTENTS
1. INTRODUCTION…………………………………………………………………...1-5 1.1 ROLLING/BENDING - A FABRICATION PROCESS……………………………..2 1.2 TYPES OF ROLLING MACHINES………………………………………………...3 1.3 DIFFERENCE BETWEEN PINCH TYPE & PYRAMID TYPE ...…………………5
2. OBJECTI VES OF MACHINE……….……………………………………………..6
3. PROBLEM DEFINITION…………………………………………………………...7
4. COST ESTIMATION………………………………………………………………..8
REFERENCES………………………………………………………………………....9
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1. INTRODUCTION A Plate Bending Machine is a machine that will roll different kind of metal sheet into a round or conical shape. It can be also called “Roll bending machine” “Plate bending Machine” or “Rolling machine”.
Fig. 1.1 Rolling Machine th From the beginning of the 20 century, it was found necessary to produce tubular sections from plates for a large variety of industrial applications. Efforts were on in all the industrially advanced countries to develop a machine that could form plates into various shapes like cylinders, cones, etc. However, it was Chr. Haeusler AG of Donarch, Switzerland who developed the world’s first plate bending and rolling machine in 1947. Rolling is a process of deforming plates plastically so as to form tubular sections like cylinders and cones. This is achieved by passing the plate in the cold or hot state through a number of rollers arranged in a particular manner. These tubular sections find wide applications in the manufacturing of pressure vessels and heat exchangers
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1.1 ROLLING/BENDING - A FABRICATION PROCESS After the pre-bending operation is done the actual process of rolling begins. Firstly, the in feed roller is lowered and made in line with the bottom roller. The pre-bent plate is fed from the input roller side to contact against the output roller. Then the top roller is moved downwards until it touches the plate so as to ensure that the plate will not slip during the time of rolling. Then the pinching of top roller change the radius of the plate and the plate is partially rolled. After partial rolling, the radius is checked with a template
(a)
(b)
(c)
Fig.1.2 Process of Rolling of required radius as shown in fig. The width of the template is generally one-fourth of the diameter of the shell to be rolled. If the radius is found satisfactory, the whole shell is rolled to that radius. After the whole shell is rolled again the radius is checked with the template. If any defect is there necessary actions are taken to rectify the same. If the radius is found to be correct, both the edges (front and trailing ends) are tack welded. The bearing of the top roller is then lowered as shown in the figure and the rolled shell is taken out with the help of the crane.
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1.2 TYPES OF ROLLING MACHINES The rolling machines are of two types. One is the pinch type rolling machine and the other is the pyramid type rolling machine. The same are discussed below
PINCH TYPE - ROLLING MACHINE In the pinch type rolling machine, the position of the rollers is as shown in the figure. In this machine, the top roller remains in fixed position. The bottom roller can move towards or away from the top roller in the vertical direction to suit the plate thickness. The side rollers are adjustable in an angular direction as shown in the figure. The angular movement of the side rollers determines the diameter of the shell to be rolled. Both the top and bottom rollers are always power driven.
Fig. 1.3 Pinch type Rolling Machine
The side rollers are idler rollers and are driven through the frictional force when the plate is moved between the top and bottom rollers. The four rollers on this machine are an advantage as it eliminates the need for edge breaking for the plates of smaller thickness. Instead the edge breaking can be done on the machine itself with one single entry. The bottom roller is used for pinching; i.e. we can roll a shell of bigger diameter from a plate of smaller length. (By applying more pressure from the bottom roller, the plate is elongated with a negligible reduction in the thickness.)
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PYRAMID TYPE- ROLLING MACHINE The arrangement of the rollers in this machine is different from the pinch type-rolling machine. This machine has three rollers arranged in a triangular form.
Fig.1.4 Pyramid type Rolling Machine
The top roller can move up and down and the side rollers can move in a direction shown in the figure. The side rollers are generally half the size of the top roller. The plate is kept on the side rollers when the top roller is in raised position. The top roller is then lowered to contact the plate and then rolling is carried out.
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1.3 DIFFERENCE BETWEEN PINCH TYPE & PYRAMID TYPE
The pinch type rolling machine can produce more nearly true cylindrical shape, because the plate is held more firmly resulting in smaller flat area at the leading and the trailing ends. For a given capacity the pinch type machine can roll a greater range of metal thickness because of the method of feed. The pinch type-rolling machine provides more dimensional accuracy as compared to pyramid type. In pyramid type rolling machine straightness of the plates can be done with more ease, since the bottom rollers are at the same elevation. The pyramid type-rolling machine can be used for rolling of sections by mounting a particular die on the roller. The pyramid type-rolling machine leaves large flat areas at the front and the trailing ends. The pyramid type-rolling machine offers certain limitations on minimum thickness of the plate, which cannot be rolled due to lack of stiffness. In case of pinch type rolling machine there are more chances of elongation of the plate. (Elongation is called as stretch). Opposite side does pre-bending of the trailing end.
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2. OBJECTIVES OF MACHINE Objective of modification is to combine Pre-bending and rolling process in one unit. Early we used to pre-bend the plates on hydraulic press and then loaded to bending machine. This result in wastage of time due to performing operation on two different machines also loading-unloading of plate from hydraulic press to plate bending machine this could be minimized by combining both processes in one machine.
Although the initial manufacturing cost of both tools is almost same, but operating modified plate bending process operator cost, labour cost is reduced to certain extent. The number of labours required during modified plate bending operation is less.
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3. PROBLEM DEFINITION Manual Operation The process of plate bending is pure manual. First plate is loaded on hydraulic press for pre bending and after bending some portion of both ends of the plate it is loaded to bending machine. In this bottom rollers are power driven and the top roller’s up-down movement is done manually. So the whole procedure is time consuming and more workmen required for this process. Also two operations are done separately on different machines which increases labour cost, operator cost, material handling cost.
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4. COST ESTIMATION
Cost estimation for Modification of Manual Plate Bending Machine
Sr. No.
Name of items
Cost(Rs.) Approx.
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Design and Development cost
10000/-
2
Fixture and Tooling cost
15000/-
3
Raw material
30000/-
4
Fabrication cost
15000/-
5
Labour cost
7500/-
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Painting
2000/-
Total cost
79,500/-
Total estimated cost of project is approximately Seventy nine thousand five hundred.
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REFERENCES SHREYAS INDUSTRIES - Girgaon, Mumbai, Maharashtra 400 004. WORKSHOP TECHNOLOGY - HAJRA CHAUDHARY www.google .com www.wkipedia.com
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