JbmCovering the Activities in the Disciplines of Automotive

7/30/2019 JbmCovering the Activities in the Disciplines of Automotive

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AJAY KUMAR GARG ENGINEERING COLLEGE27 DELHI-HAPUR BYPASS ROAD

GHAZIABAD-201009

A

INDUSTRIAL TRAINING REPORT

ON

PRODUCTION TECHNOLOGY

AT

NEEL AUTO PRIVATE LIMITED

BEHRAMPUR INDUSTRIAL AREA

BEGAMPUR-KHATOLA ROAD, KHANDSA,

GURGAON-122001 HARYANA(INDIA)

SUBMITTED BY UNDER THE GUIDANCE OF

ASHISH GOEL RAMANDEEP SINGH

IIyr ME PRODUCTION MANAGER

1102740032


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AJAY KUMAR GARG ENGINEERING COLLEGE27 DELHI-HAPUR BYPASS ROAD

GHAZIABAD-201009

TRAINING CERTIFICATE

It is to certify that Ashish Goel student of AJAY KUMAR GARG

ENGINEERING COLLEGE B.tech 3rd yr student MECHANICAL

branch

Has undergone industrial training on PRODUCTION

TECHNOLOGY.

I.P SHARMA P.K CHOPRA

(H.O.D MECHANICAL) VSM, Proff-HOD T&P


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Introduction

Understanding the importance of manufacturing's infrastructure, to

remain competitive, provide better products to its customers, increase its

customer base, and develop new business areas, TSNA identifies andsupplies each customer's unique requirements with an integrated set of

products and services that fit cost, timeliness, and functional requirements

and that are flexible enough to evolve with changes in the customer's needs.

To develop custom-tailored products and services rapidly, to improve theknowledge and capability, TSNA draws partnerships from within or outside the

country. The TSNAs manufacturing strategies allow tailoring product

structures to meet customer requirements any place around the globe.

The TSNAs Infrastructure is set up to develop advanced manufacturing

systems, advanced enterprise concepts, engineering tools, manufacturingprocesses and equipment, product design and modeling, to cut time to market

and to integrate product and system design, manufacturing, and testing.

Neel Auto Private Limited manufactures and supplies automotive components

for two-wheelers. It offers sheet metal components such as fuel tanks, framesand chassis parts for two-wheeler manufacturers. The company deals in

automotive parts, motorcycle parts and agricultural machine parts. Neel AutoPrivate Limited was formerly known as Thai Summit Neel Auto Pvt. Ltd. As a

result of the acquisition of Thai Summit Neel Auto Pvt. Ltd. by Neel Metal

Products Limited, Thai Summit Neel Auto Pvt. Ltd.'s name was changed in

December 2012. The company was incorporated in 2003 and is based inGurgaon, India. Neel Auto Private Limited operates as a subsidiary of Neel

Metal Products Limited.

A joint venture Company between Thai Summit group of Thailand and JBM

group of India with 50 - 50 equity partnership. Thai Summit Group of Thailandcomprises of more than 30 companies dealing in automotive parts, motorcycle

parts and agriculture machine parts with more than 30 years experience. JBM

Group is the leading sheet metal components in India dealing in Automotive

and related industry with more than 10 companies in the group and over 20

years of experience.

Covering the activities in the disciplines of automotive, steel service,

fabrication, construction, and waste management, The JBM, after its

reorganization, has emerged as a leading Group. Its automotive sector hasachieved outstanding perfection in high quality production. By the


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involvement of internationally reputed players in the technical

advancement in the growth and development, the Group has received

recognition in the wide ranging costumer preferences.

Over the years, the Group has diversified its activities covering other areas ofpublic importance. In the year 2007 the Group ventured in the sector of waste

management and today it provides a novel service to the people in this section

in the cities of Chennai and Ambattur.

JBM Group is a New Delhi headquartered diversified conglomerate with

presence in automotive, education and engineering service in India. With a

major presence of around three decades, the Group has earned recognition,

awards and accolade globally. The Group pioneered and revolutionised the

industry with state-of-the-art technology in the field of automotive, engineering

and design and today has 33 Manufacturing Plants, 5 Engineering & Design

Centres across 19 locations worldwide. With a turnover of USD 1.2 billion, the

Group is well diversified and professionally managed with focus on quality,

leadership and fast product development process, contract manufacturing and

flexible manufacturing systems. JBM Group caters to clients in Automobile like

Ashok Leyland, Bajaj, Eicher, Fiat, Ford, GM, Hero, Honda, JCB, Mahindra,

Maruti Suzuki, Nissan, Renault, TATA, Toyota, TVS, Volkswagen, Volvo and

many more. JBM Group has alliances with 20 renowned companies of the

world like Arcelor Mittal, Dassault Systemes, JFE Steel Corporation, Sumitomo

Corporation, Magnetto Automotive and many others. Furthermore, the Group is

committed to social development initiatives and executes these through its

Corporate Social Responsibility arm, Neel Foundation.

LOCATION

It is located in Behrampur Industrial Area, Begumpur-Khandsa Road, vill.KHANDSA, GURGAON near maruti weldings, near 20km distant from Huda

city Centre.


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RESAERCH AND DEVELOPMENT

Continuous development in the field of research and technology is the crucialdriver for the daily operations of Neel auto pvt. Ltd. for increasing ability and

potential for competitiveness in the market, which helps to meet the customers'

needs and expectations at every stage since concept design, toolings design and

finally joint part designing capabilities with the customers, which enable us toalways provide services to our customers, whether the customers have CAD

design or not. We use FEA Testing for analyzing the part structure, forming

process of metal parts, forming process of plastic injection parts, RobCad and

analyse up to process automation using robots in order to produce the highest

quality products with consistency. We use latest tooling, machines &equipments and testing machines & equipments for both in house andoutsourced processes.

Before manufacturing tooling all processes receive careful supervision of highly

experienced personnels, who have expertise and specialization in the product

research and development in the group. Research and development are theessential driver which helps to run the groups operations smoothly and develop

customers confidence that they will get the products and services which are of

the highest quality and international standards.

Achievements

6th August, 2003 MOU signed by TSA to set up joint venture in India

12th November, 2003 Joint Venture Signed between TSA and JBM

2nd December, 2003 Company formation

15th April, 2005 Inauguration of Gurgaon Plant & Start of Production

2nd january, 2006 Takeover of Hosur Unit

(Near Bangalore from Sundaram Auto Components Limited TVS Group

Company)

1st March, 2006 Start of Production at Chakan Plant

9th April, 2007 Start of Production at Pantnagar Plant

26th March, 2010 Start of Production at Nalagarh Plant


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Aim / Vision / Mission

" Be a leader in our business through world class manufacturing practices

development of our people and keeping pace with market and technology."

" We at TSN are committed to make it a World Class Organistion and a

preferred supplier of engineering goods."

Team / Manpower

V K Kapur President

Songpol Thongchut Technical Center

Harish Yadav Human Resources

Sandeep Gupta Finance

Sudhir Grover Supply Chain

S V Nandi Projects

Vivek Rai Information Technology

Santosh Pandey Business Development

Suresh Kumar Sharma Unit Head Pantnagar

Nandkishore M. Fanse Unit Head Chakan

G Ravi Kumar Unit Head Hosur Plant - I

Kalyan Raman Unit Head Hosur Plant - II

Kamaljit Bhatti Unit Head Nalagarh

Quality Policy / Processes


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We, at Thai Summit Neel are commited to manufacture and supply Auto

Components ensuring Customer Satisfaction through continual improvements

and Total Employee Involvement.

ORGANISATIONAL SET-UP

SHARE HOLDER

BOARD

DIRECTOR

PRODUCTIONDEPARTMENT

PRODUCTIO PLANING

TECH./INDUSTRIAL

DESIGN

PRODUCTION

QA MANAGER

MAINTANENCE

INVESTMENT DEPARTMENT

PLANING DEPARTMENT

RESAERCH DEPARTMENT

ENGINEERINGDEPARTMENT

MARKETING DEPARTMENT

BRAND/ADVERTISINGDEPARTMENT

PROMOTIONS/MEDIA

TRADE MARKETING PUBLIC RELATIONS

MARKET ANALYSIS

TECHNICAL DEPARTMENT

PRODUCT DESIDNDEPARTMENT

RESOURCE/DEVELOPMENTDEPARTMENT

TECHNICAL AUDITDEPARTMENT

TECHNICAL SERVICEDEPARTMENT

HUMAN RESOUSCEDEPARTMENT

TRAING GROUP

RECRUITMENT TEAM

OFFICESUPERVISIR

COMPENSATION/BENIFITS


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VARIOUS DEVISIONS FOR EFFICIENT

WORKING

METAL HANDLING DIVISION

This division takes care of sheet and various parts for the supply to

various divisions.

SHEET METAL DIVISION

This division deals with the various metal cutting processes like

punching, piercing, blanking, and forming processes.

DRILING/CUTTING DIVISION

This division deals with the various metal drilling, boring and reaming,

metal cutting, grinding and milling processes.

WELDING DEVISION

This division deals with the various types of welding processes.

PAINTING DIVISION

This division deals with the painting of various automobile parts.

STORE AND PURCHASE DIVISION

This division deals with the storage and supply of various spare parts

according to the demand.

TRANSPORTATION DIVISION


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This division looks after the transportation of fuel.

Literature Survey

Objective of Literature Survey: It is the detailed study of each process that

comes under the sequential production.

It is much needed to understand the

manufacturing thoroughly.

Various processes are as follows:

SHEARING PROCESS:

Shearing is a cutting force applied

perpendicular to material causing the

material to yield and break. Shearing is

a process for cutting sheet metal to size

out of a larger stock such as roll stock. Shears are used as the preliminary step

in preparing stock for stamping processes, or smaller blanks for CNC presses.

Material thickness ranges from

0.125 mm to 6.35 mm (0.005 to 0.250 in). The dimensional tolerance ranges

from 0.125 mm to 1.5 mm (0.005 to 0.060 in).

The shearing process produces a shear edge burr, which can be minimized to

less than 10% of the material thickness. The burr is a function of clearance

between the punch and the die (which is nominally designed to be the material

thickness), and the sharpness of the punch and the die.

The illustration shown provides a two-dimensional look at a typical metal

shearing process. Note how the upper shear blade fractures the metal workpiece

held in place by the workholding devices. The sheared piece drops away.

Typically, the upper shear blade is mounted at an angle to the lower blade that is

normally mounted horizontally. The shearing process performs only

fundamental straight-line cutting but any geometrical shape with a straight line

cut can usually be produced on a shear.


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Metal shearing can be performed on sheet, strip, bar, plate, and even angle

stock. Bar and angle materials can only be cut to length. However, many shapes

can be produced by shearing sheet and plate.

Fig. shows a shearing machine:

This is a modern shearing machine that can be used to cut the sheets with a

smoother operation and high accuracy. The shearing tool imparts the force

hydraulically and the operating pedal works pneumatically. The gauge size can

be set with a program to cut bars of specific size from a larger sheet. There are

supporting anvils for longer sheets. The shearing tool is mounted a bit inclined

to x-axis, as to produce trimming effect and to avoid bending of sheet due to

single stroke.

Generally this is used to get a blank sheet out of raw materials. It is also used to

cut the scrap material and take out the productive portions.

The shearing process characteristics include:


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Its ability to make straight-line cuts on flat sheet stock.

Metal placement between upper and lower shear blades.

Its trademark production of burred and slightly deformed metal edges.

Its ability to cut relatively small lengths of material at any time since the

shearing blades can be mounted at an angle to reduce the necessaryshearing force required.

PUNCHING PROCESS:

Punching is a metal fabricating process that removes a scrap slug from the metal

workpiece each time a punch enters the punching die. This process leaves a hole

in the metal workpiece.

CNC Punching and Blanking:

Punching is the process of forming metal components using a punch. The punch

is usually the upper member of the complete die assembly and is mounted on

the slide or in a die set for alignment (except in the inverted die).

The punching process forces a steel punch, made of hardened steel, into and

through a workpiece. The punch diameter determines the size of the holecreated in the workpiece.

The illustration that follows

provides a two-dimensional look at a

typical punching process. Note how the

workpiece remains and the punched

part falls out as scrap as the punch

enters the die. The scrap drops through

the die and is normally collected forrecycling.

Fig. shows a CNC turret machine used

for punching purpose:


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The Computer Numerical Control (CNC) fabrication process offers flexible

manufacturing runs without high capital expenditure dies and stamping presses.

High volumes are not required to justify the use of this equipment.

Tooling is mounted on a turret which can be as little as 10 sets to as much as

100 sets. This turret is mounted on the upper part of the press, which can range

in capacity from 10 tons to 100 tons in capacity.

The turret travels on lead screws, which travel in the X and Y direction and are

computer controlled. Alternatively, the workpiece can travel on the lead screws,

and move relative to the fixed turret. The tooling is located over the sheet metal,

the punch is activated, and performs the operation, and the turret is indexed to

the next location of the workpiece. After the first stage of tooling is deployed

over the entire workpiece, the second stage is rotated into place and the whole

process is repeated. This entire process is repeated until all the tooling positions

of the turret are deployed.

The illustration that follows shows a few common punches and die

configurations and the workpieces that would be formed by this combination.

Multiple punches can be used together to produce a complete part with just one

stroke of the press.

There are 20 different tool and die holders on which various tools with their

specific dies can be mounted. There are certain dies for thin and thick sheets,


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depending upon sheet thickness. Mainly there

are three stations, B, C and D depending on

the tool and die size.

Blanking is a metal fabricating process,

during which a metal workpiece is removed

from the primary metal strip or sheet when it

is punched. The material that is removed is

the new metal workpiece or blank.

The blanking process forces a metal punch into a die that shears the part from

the larger primary metal strip or sheet. A die cut edge normally has four

attributes. These include:

burnish

burr

fracture

roll-over

The illustration that follows provides a

twodimensional look at a typical blanking

process.

Note how the primary metal workpiece

remains and the punched part falls out as scrap as

the punch enters the die. The scrap drops through the die and is

normally collected for recycling.

Like many other metal fabricating processes,

especially stamping, the waste can be

minimized if the tools are designed to nest

parts as closely together as possible.

The illustration that follows shows the workpieces that could be created

through the blanking process using either sheet or roll as the parent material.

Quite often, curves and other difficult

features are produced by punching out

small sections at a time. This process is

called nibbling. This leads to triangular

shaped features. These triangular


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shaped features give the edge a scalloped look. This scalloping can be

pronounced if the nibbling pitch is coarse. The amount of scalloping that can be

accepted is a function of tooling and product cost. Clamp marks are cosmetic in

nature, and if objectionable, can be so positioned to cut them away in

subsequent processing.

The limitations for CNC turret: Maximum limit for various materials:

Aluminium- 5mm, Mild steel- 3mm, Copper- 4mm and Brass- 3mm.

Continuous cooling is required for proper and safe operation. An oil tank is also

used to provide oil for extensive lubrication that is necessary to avoid wear of

job and tool. Mostly all jobs can be done on CNC for punching purpose, but

there are some limitations of it, due to which there arises the need of Laser CNC

machine.

BENDING PROCESS:

Bending is a process by which metal can be deformed by plastically deformingthe material and changing its shape. The material is stressed beyond the yield

strength but below the ultimate

tensile strength. The surface area of

the material does not change much.

Bending usually refers to

deformation about one axis.

Bending is a flexible process by

which many different shapes canbe produced. Standard die sets are

used to produce a wide variety of

shapes. The material is placed on the die, and positioned in place with stops

and/or gauges. It is held in place with hold-downs. The upper part of the press,

the ram with the appropriately shaped punch descends and forms the V-shaped

bend.

Bending is done using Press Brakes. Press Brakes normally have a capacity of

20 to 200 tons to accommodate stock from 1m to 4.5m (3 feet to 15 feet).


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Larger and smaller presses are used for specialized applications. Programmable

back gauges, and multiple die sets available currently can make for a very

economical process.

The minimum flange width should be at least 4times the stock thickness plus the bending

radius. Violating this rule could cause

distortions in the part or damage to tooling or

operator due to slippage.

Fig. shows a hydraulic press (Bending machine):

The machine has a stationary bed or anvil and a slide (ram or hammer) which

has a controlled reciprocating motion toward and away from the bed surface and


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at right angle to it. The slide is guided in the frame of the machine to give a

definite path of motion.

A form of open-frame single-action press that is comparatively wide between

the housings, with a bed designed for holding long, narrow forming edges ordies. Used for bending and forming strip, plate, and sheet (into boxes, panels,

roof decks, and so on).

Dies used in presses for bending sheet metal or wire parts into various shapes.

The work is done by the punch pushing the stock into cavities or depressions of

similar shape in the die or by auxiliary attachments operated by the descending

punch. Various types of machinery equipped with two or more rolls to form

curved sheet and sections.

WELDING PROCESS:

Welding is the process of permanently joining two or more metal parts, by

melting both materials. The molten materials quickly cool, and the two metals

are permanently bonded.

Mainly used welding types are Argon (TIG) welding and MIG welding.

TIG welding:

TIG welding is a slower process than MIG, but it produces a more precise weld

and can be used at lower amperages for thinner metal and can even be used on

exotic metals. TIG welding is a commonly used high quality welding process.

TIG welding has become a popular choice of welding processes when highquality, precision welding is required. The TIG welding process requires more

time to learn than MIG.

Characteristics:


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Uses a non-consumable tungsten electrode during the welding process,

Uses a number of shielding gases including helium (He) and argon (Ar),

Is easily applied to thin materials,

Produces very high-quality, superior welds,

Welds can be made with or without filler metal,

Provides precise control of welding variables (i.e. heat), Welding yields

low distortion, Leaves no slag or splatter.

In TIG welding, an arc is formed between a non-consumable tungsten electrode

and the metal being welded. Gas is fed through the torch to shield the electrode

and molten weld pool. If filler wire is used, it is added to the weld pool

separately.

The illustration that follows provides a schematic showing how the TIG

welding process works.

The following illustration shows the TIG-welded joints:

MIG welding:


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The "Metal" in Gas Metal Arc Welding refers to

the wire that is used to start the arc. It is shielded

by inert gas and the feeding wire also acts as the

filler rod. MIG is fairly easy to learn and use as it is

a semi-automatic welding process.

Welding gun

GMAW torch nozzle cutaway image: (1) Torch

handle, (2) Molded phenolic dielectric (shown in

white) and threaded metal nut insert (yellow), (3)

Shielding gas diffuser, (4) Contact tip, (5) Nozzle

output face Characteristics:

Uses a consumable wire electrode during the welding process that is fed

from a spool,

Provides a uniform weld bead,

Produces a slag-free weld bead,

Uses a shielding gas, usuallyargon, argon - 1 to 5% oxygen, argon - 3

to 25% CO2 and a combination argon/helium gas,

Is considered a semi-automatic welding process,

Allows welding in all positions,

Requires less operator skill than TIG welding, Allows long welds to

be made without starts or stops, Needs little cleanup.

The illustration that follows provides a look at a typical MIG welding process

showing an arc that is formed between the wire electrode and the workpiece.

During the MIG welding process, the electrode melts within the arc and

becomes deposited as filler

material. The shielding gas thatis used prevents atmospheric

contamination from

atmospheric contamination and

protects the weld during

solidification. The shielding gas

also assists with stabilizing the

arc which provides a smooth


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transfer of metal from the weld wire

to the molten weld pool.

Versatility is the major

benefit of the MIG welding process.It is capable of joining most types of

metals and it can be performed in

most positions, even though flat

horizontal is the optimum.

The most common welds are

illustrated below. They include the:

lap joint butt joint

T-joint, and the

edge joint

MIG is used to weld many materials, and different gases are used to form the

arc depending on the materials to be welded together. An argon CO2 blend is

normally used to weld mild steel, aluminum, titanium, and alloy metals. Helium

is used to weld mild steel and titanium in high speed process and also copperand stainless steel. Carbon dioxide is most often used to weld carbon and low

alloy steels. Magnesium and cast iron are other metals commonly welded used

the MIG process.

GRINDING PROCESS:

Grinding is a finishing process used to improve surface finish, abrade hard

materials, and tighten the tolerance on flat and cylindrical surfaces by removinga small amount of material. In grinding, an abrasive material rubs against the

metal part and removes tiny pieces of material. The abrasive material is

typically on the surface of a wheel or belt and abrades material in a way similar

to sanding. On a microscopic scale, the chip formation in grinding is the same

as that found in other machining processes. The abrasive action of grinding

generates excessive heat so that flooding of the cutting area with fluid is

necessary.


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Machine tool uses a

rotating abrasive grinding wheel

to change the shape or dimensions of a

hard, usually metallic,

workpiece.Grinding is the most accurate of all the

basic machining processes. All

grinding machines use a wheel made

from one of the manufactured

abrasives, silicon carbide

or aluminum oxide.

To grind a cylindrical form,

the workpiece rotates as it is fed

against the grinding wheel. To grind an

internal surface, a small wheel moves

inside the hollow of the workpiece,

which is gripped in a rotating chuck.

On a surface grinder, the workpiece is

held in place on a table that moves

under the rotating abrasive wheel.

POWDER COATING PROCESS:

Powder coating is a dry finishing process, using finely ground particles of

pigment and resin that are generally electrostatically charged and sprayed onto

electrically grounded parts. The charged powder particles adhere to the parts

and are held there until melted and fused into a smooth coating in a curing oven.

Before coating, the parts to be coated are first pretreated similarly to

conventional liquid coated parts. The pretreatment process is normally

conducted in series with the coating and curing operations.


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There is essentially two common ways

of applying powder coating: by

electrostatic spray and by fluidized bed

powder coating. There are several other

processes that have been developed, but

they are far less used. These include

flame spraying, spraying with a plasma

gun, airless hot spray, and coating by

electrophoretic deposition.

Electrostatic spray powder coating uses

a powder-air mixture from a small

fluidized bed in a powder feed hopper. In some cases, the feed hoppers vibrateto help prevent clogging or clumping of powders prior to entry into the transport

lines. The powder is supplied by a hose to the spray gun, which has a charged

electrode in the nozzle fed by a high voltage dc power.

Electrostatic powder spray guns direct the flow of powder; control the

deposition rate; control the pattern size, shape, and density of the spray; and

charge the powder being sprayed .The spray guns can be manual (hand-held) or

automatic, fixed or reciprocating, and mounted on one or both sides of a

conveyorized spray booth. Electrostatic spray powder coating operations use

collectors to reclaim over-spray. This reclaimed powder is then reused, adding

significantly to the powder coating's high transfer efficiency.

The film thickness is dependent on the powder chemistry, preheat temperature,

and dwell time. The different surface finishes obtained by powder coating

include matt finish, texture finish, glossy finish, etc.

Finally, the last step is the packing and despatch of the completed job which is

done in a manner depending on the type and shape of the job made, its delicacy,

etc.


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Analysis:

Bending process:

The bending force for sheet metal in Vdies,

Where, Su=ultimate tensile strength, psi

W=width of metal at bend, in.

t=metal thickness, in.

L=length of span across die opening

Eg:

For bending a 1 inch thick and 10 inch broad M.S. Sheet of 70 ksi. tensilestrength is to be bend with a V-die of opening 3 inch then the bending

force is :

Su = 70 ksi.

Production

The designs dept. feed the input to the prod. dept. It provides the finalised

drawing and the part list. This part list is then used to get the results for optimise

use of available raw material with the help of a software, Plus 2D. It give the

effective productivity on the basis of raw material and parts. Minimum criteria

followed here is 92 % overall.


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According to mentioned sequence, the first stop is shearing. The operator is

given a drawing or just the figure of final dimensional of sheet that is required

of raw material for jobwork. The worker prepare the specific blank sheet for

further processing.

We saw the operation of the shearing machine and its observed the precautions

to be taken. Also studied the mechanism of the mechanism just by observing as

we were not authorized to operate it. But the presence of mind made it easier to

grasp the process funda and the style of the operator.

The sheet is then either fabricated under CNC turret or Laser machine under

various circumstances. For CNC work, the CNC operator is given a notepad file

via network. He manipulate various parameters and sets the tool and die

combinations as per mentioned in the file. Then as the computer is connected toCNC, the CNC reads the required job file and the operator initiates the process

of punchng in CNC. The accomplished job requires grinding and finishing.

The CNC machine was the most fascinating machine to observe, the operator

told us about the program manipulating and its relation to the tool sequence in

turret of CNC. We saw the mounting of die and punch combinationsfor

punching purpose. There is a neutral indicating point at whiah job is to be fixed,

in order to get the perfect output.

For Laser process, the operator is provided with a .dxf file that he used to

generate a a program file for Laser input with a flopppy disk. The job is then

fixed on the table at neautral point according to axes. The operator initiates the

machine work, Laser automatically arrange the sequence of various cuttings in

job. The finishing of job is not required cause of good quality cutting and

deburred edges.

The job then moves to the bending shop. Here the operator understands the job

and its diagram to carry on the required process. The symbols like BUP and

BDN shows about the direction of bend to be applied on job. The operator sets

the feed into CNC bending machine (Press Brake), and arrange the suitable

punch and die for the required job. The job is then set onto the bolster against

the gauge that maintains the simension of a portion of sheet to be bend. The

final job is then proceeded for further operations.

We acknowledged the importance of press brake.It was intresting to watch the

operation of the bending machine as around 100 tons of force is applied to make

the sheet at right angle or some specific angle.


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The job is taken to the welding area. The job and its edges are properly cleaned

to avoid any inclusions at the time of welding. The job is then kept on an anvil

or support frame to weld. The bend edges ar then welded by MIG or Argon

welding.The job is then left idle to get cooler.

The job is further proceeded for grinding process. Here the edges and the weld

portioned is grinded with the help of grinder with abrasive wheel the remove the

burr off the edges. Also the the weld foul appearance is improved a lot by this

grinding processes.

The job is then moved on for final coating. Generally the powder coating is

done to give it durable outer membrane. This process increase the corrosion

resistance and the life of the material. Mostly the various types of finish in

powder coating are done on customer demands.

It was great to watch the whole process of fabrication for a shhet material upto

ready enclosure or panel (Job). The fixed sequence of observing helped us to

uderstand the pros and cons of various process.


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POWDER PAINTING


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Powder coating is a type of coating that is applied as a free-flowing, drypowder. The main difference between a conventional liquid paint and a powder

coating is that the powder coating does not require a solvent to keep the binder

and filler parts in a liquid suspension form. The coating is typically applied

electrostatically and is then cured under heat to allow it to flow and form a

"skin". The powder may be a thermoplastic or a thermoset polymer. It is usually

used to create a hard finish that is tougher than conventional paint. Powder

coating is mainly used for coating of metals, such as household appliances,

aluminium extrusions, drum hardware, and automobile and bicycle parts. Newertechnologies allow other materials, such as MDF (mediumdensity fibreboard),

to be powder coated using different methods.

Advantages and disadvantages

There are several advantages of powder coating over conventional liquid

coatings:

1. Powder coatings emit zero or near zero volatile organic compounds

(VOC).

2. Powder coatings can produce much thicker coatings than conventional

liquid coatings without running or sagging.

3. Powder coating overspray can be recycled and thus it is possible to achieve

nearly 100% use of the coating.

4. Powder coating production lines produce less hazardous waste than

conventional liquid coatings.

5. Capital equipment and operating costs for a powder line are generally lessthan for conventional liquid lines.


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6. Powder coated items generally have fewer appearance differences between

horizontally coated surfaces and vertically coated surfaces than liquid

coated items.

7. A wide range of specialty effects is easily accomplished which would be

impossible to achieve with other coating processes.

While powder coatings have many advantages over other coating processes,there are some disadvantages to the technology. While it is relatively easy toapply thick coatings which have smooth, texture-free surfaces, it is not as easyto apply smooth thin films. As the film thickness is reduced, the film becomesmore and more orange peeled in texture due to the particle size and glasstransition temperature (TG) of the powder. On smaller jobs, the cost of powdercoating will be higher than spray painting.

For optimum material handling and ease of application, most powder coatings

have a particle size in the range of 30 to 50 m and a TG around 200C. For

such powder coatings, film build-ups of greater than 50 m may be required to

obtain an acceptably smooth film. The surface texture which is considered

desirable or acceptable depends on the end product. Many manufacturers

actually prefer to have a certain degree of orange peel since it helps to hide

metal defects that have occurred during manufacture, and the resulting coating

is less prone to showing fingerprints.

There are very specialized operations where powder coatings of less than 30micrometres or with a TG below 40C are used in order to produce smooth thin

films. One variation of the dry powder coating process, the Powder Slurry

process, combines the advantages of powder coatings and liquid coatings by

dispersing very fine powders of 15 micrometre particle size into water, which

then allows very smooth, low film thickness coatings to be produced.

Powder coatings have a major advantage in that the overspray can be recycled.

However, if multiple colors are being sprayed in a single spray booth, this maylimit the ability to recycle the overspray.

Types of powder coatings

There are two main categories of powder coatings: thermosets and

thermoplastics. The thermosetting variety incorporates a cross-linker into the

formulation. When the powder is baked, it reacts with other chemical groups in

the powder to polymerize, improving the performance properties. The

thermoplastic variety does not undergo any additional actions during the bakingprocess, but rather only flows out into the final coating.


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The most common polymers used are polyester, polyurethane, polyester-epoxy

(known as hybrid), straight epoxy (fusion bonded epoxy) and acrylics.

Production:

1. The polymer granules are mixed with hardener, pigments

and other powder ingredients in a mixer 2. The mixture is

heated in an extruder

3. The extruded mixture is rolled flat, cooled and broken into small chips

4. The chips are milled and sieved to make a fine powder

The powder coating process

The powder coating process involves three basic steps:

1. Part preparation or the pre-treatment

2. The powder application

3. Curing

Part preparation processes and equipment

Removal of oil, soil, lubrication greases, metal oxides, welding scales etc. isessential prior to the powder coating process. It can be done by a variety of

chemical and mechanical methods. The selection of the method depends on the

size and the material of the part to be powder coated, the type of soil to be

removed and the performance requirement of the finished product.

Chemical pre-treatments involve the use of phosphates or chromates in

submersion or spray application. These often occur in multiple stages and

consist of degreasing, etching, de-smutting, various rinses and the final

phosphating or chromating of the substrate. The pre-treatment process both

cleans and improves bonding of the powder to the metal. Recent additional

processes have been developed that avoid the use of chromates, as these can be

toxic to the environment. Titanium zirconium and silanes offer similar

performance against corrosion and adhesion of the powder.

In many high end applications, the part is electrocoated following the

pretreatment process, and subsequent to the powder coating application. This

has been particularly useful in automotive and other applications requiring highend performance characteristics.


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Another method of preparing the surface prior to coating is known as abrasiveblasting or sandblasting and shot blasting. Blast media and blasting abrasivesare used to provide surface texturing and preparation, etching, finishing, anddegreasing for products made of wood, plastic, or glass. The most important

properties to consider are chemical composition and density; particle shapeand size; and impact resistance.

Silicon carbide grit blast medium is brittle, sharp, and suitable for grinding

metals and low-tensile strength, non-metallic materials. Plastic media blast

equipment uses plastic abrasives that are sensitive to substrates such as

aluminum, but still suitable for decoating and surface finishing. Sand blast

medium uses high-purity crystals that have low-metal content. Glass bead blast

medium contains glass beads of various sizes.

Cast steel shot or steel grit is used to clean and prepare the surface before

coating. Shot blasting recycles the media and is environmentally friendly.This method of preparation is highly efficient on steel parts such as I-beams,angles, pipes, tubes and large fabricated pieces.

Different powder coating applications can require alternative methods of

preparation such as abrasive blasting prior to coating. The online consumer

market typically offers media blasting services coupled with their coating

services at additional costs.

Powder application processes

The most common way of applying the powder coating to metal objects is to

spray the powder using an electrostatic gun, or corona gun. The gun imparts a

positive electric charge to the powder, which is then sprayed towards the

grounded object by mechanical or compressed air spraying and then accelerated

toward the workpiece by the powerful electrostatic charge. There are a widevariety of spray nozzles available for use in electrostatic coating. The type of

nozzle used will depend on the shape of the workpiece to be painted and the

consistency of the paint. The object is then heated, and the powder melts into a

uniform film, and is then cooled to form a hard coating. It is also common to

heat the metal first and then spray the powder onto the hot substrate. Preheating

can help to achieve a more uniform finish but can also create other problems,


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Example of powder coating spray guns

such as runs caused by excess powder. See the article "Fusion Bonded Epoxy

Coatings"

Another type of gun is called a tribo gun, which charges the powder by

(triboelectric) friction. In this case, the powder picks up a positive charge while

rubbing along the wall of a Teflon tube inside the barrel of the gun. These

charged powder particles then adhere to the grounded substrate. Using a tribo

gun requires a different formulation of powder than the more common corona

guns. Tribo guns are not subject to some of the problems associated with corona

guns, however, such as back ionization and the Faraday cage effect. Powder can

also be applied using specifically adapted electrostatic discs. Another method of

applying powder coating, called the fluidized bed method, is by heating the

substrate and then dipping it into an aerated, powder-filled bed. The powder

sticks and melts to the hot object. Further heating is usually required to finish

curing the coating. This method is generally used when the desired thickness of

coating is to exceed 300 micrometres. This is how most dishwasher racks are

coated.

Electrostatic fluidized bed coating

Electrostatic fluidized bed application uses the same fluidizing technique andthe conventional fluidized bed dip process but with much less powder depth in

the bed. An electrostatic charging medium is placed inside the bed so that the

powder material becomes charged as the fluidizing air lifts it up. Charged

particles of powder move upward and form a cloud of charged powder above

the fluid bed. When a grounded part is passed through the charged cloud the

particles will be attracted to its surface. The parts are not preheated as they are

for the conventional fluidized bed dip process.

Electrostatic magnetic brush (EMB) coating


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An innovative coating method for flat materials that applies powder coating

with roller technique, enabling relative high speeds and a very accurate layer

thickness between 5 and 100 micrometre. The base for this process is

conventional copier technology.

Currently in use in some high- tech coating applications and very promisingfor commercial powder coating on flat substrates (steel, aluminium, MDF,

paper, board) as well in sheet to sheet and/or roll to roll processes. Thisprocess can potentially be integrated in any existing coating line.

Curing

When a thermoset powder is exposed to elevated temperature, it begins to melt,

flows out, and then chemically reacts to form a higher molecular weight

polymer in a network-like structure. This cure process, called crosslinking,requires a certain temperature for a certain length of time in order to reach full

cure and establish the full film properties for which the material was designed.

Normally the powders cure at 200C (390F) for 10 minutes. The curing

schedule could vary according to the manufacturer's specifications. The

application of energy to the product to be cured can be accomplished by

convection cure ovens, infrared cure ovens, or by laser curing process. The

latter demonstrates significant reduction of curing time.

Removing powder coating

Methylene chloride and Acetone are generally effective at removing powdercoating, however most other organic solvents (thinners, etc.) are completelyineffective. Most recently the suspected human carcinogen methylene chlorideis being replaced by benzyl alcohol with great success. Powder coating can also

be removed with abrasive blasting. 98% sulfuric acid commercial grade alsoremoves powder coating film.

[citation needed]Certain low grade powder coats can be

removed with steel wool, though this might be a more labor-intensive process

than desired. Powder coating can also be removed by a burning off process, inwhich parts are put into a large high-temperature oven with temperaturestypically reaching an air temp of 1100 to 1500 degrees with a burnertemperature of 900. The process takes about four hours and requires the parts to

be cleaned completely and repowdered. Parts made with a thinner-gage materialneed to be burned off at a lower temperature to prevent the material fromwarping.

Conclusion


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We conclude from this training that the various processes as applied are

dependent on various parameters. A good co-ordination is the key to get best

efficiency and high productivity.

Each and every process depends on factors such as the method used to carry

out the process, the type of the material used (whether Aluminium, Mild

Steel, Brass, etc.) and the thickness of the material (or sheet).

At the process of development of surfaces, the allowances are to be

increased as per the thickness of metal.

The bending force on the job increases with broadness and thickness of job

but decreases with the length of die opening.

In the technical aspect, we conclude that nothing can be understood

thoroughly without practical knowledge and practice. We observed almost each

process related to sheet metal fabrication that we had just studied in books. It

was really a fruitful training for us to enhance our knowledge and confidence

level.

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JbmCovering the Activities in the Disciplines of Automotive