Training Report of NBC Bearing

Project report on training in National Bearing Company

ENGINEERING PROJECT

REPORT

ON

INDUSTRIAL TRAINING

IN NATIONAL BEARING COMPANY

FOR THE PARTIAL FULFILLMENT OF

THE REQUIREMENT OF

BACHELOR OF TECHNICAL EDUCATION

SUBMITTED BY

KETAN TOSHNIWAL

IV YEAR, MECHANICAL ENGINEERING

A2 – BATCH, ROLL NO ME052

GYAN VIHAR SCHOOL OF ENGINEERING & TECHNOLOGY

1


JAIPUR

2


TABLE OF CONTENT

Executive Summary

Acknowledgement

Preface

Introduction to Bearings

Bearing industry

Global Scenario

Indian Bearing Industry

Threats and limitation to Indian Market

Organizational Profile

Introduction

Mile Stones

Company Profile

Research & Development

Quality Management System

Bearing Manufacturing

Flow of Material in Bearing Industry

Classification of Bearing

Types & Features of Rolling Bearing

Bearing Designation in NBC

Ball Bearing Manufacturing

Inner & Outer Ring Manufacturing

Spherical Ball Manufacturing

Cage Manufacturing

3


Rivet Manufacturing

Ball Bearing Assembly Line

Roller Bearing Manufacturing

Inner & Outer Manufacturing for Spherical,

Cylindrical & Tapered Roller Bearing

Roller Manufacturing

Cage Manufacturing

Roller Bearing Assembly

Railway Bearing Manufacturing

Railway Bearing Assembly Line

Heat Treatment

Heat Treatment Process

Hardening Procedure for High Carbon Steel

Hardening Procedure for Low Carbon Steel

Salt Bath Furnace

Heat Treatment flow Chart

Conclusion

4


EXECUTIVE SUMMARY

NBC Bearings Limited, a member company of C.K. BIRLA group of Companies - is a

leading player in the Indian Bearing industry.

The company manufactures a very wide range of bearings conforming to the stringent

international quality standards.

NBC manufacturing plants, located at Gunsi (Newai) Rajasthan, Manesar Haryana &

Jaipur - was incorporated in the year 1946. Its feature the most advanced manufacturing

technology. The company is certified to ISO/TS 16949, ISO 9001, and ISO 14001

standards.

NBC India is a leading OEM supplier to the automotive industry, mechanical and

electrical engineering industry, besides the Railways.

Bearings produced at the EOU plant have gained ready acceptance and recognition of

customers located in India & Indian Sub Continent, Europe & Africa.

NBC’s main competitors in bearing are SKF, TIMKEN, NRB, FAG and other local

brands.

OBJECTIVE:

The main objective of this training is to learn different engineering processes and to

develop skills and with that attitude I had done my engineering training with NBC

Bearings Ltd. In this one month training period I had seen different work and key

responsibility of various bearings department.

Training was started with brief introduction program of NBC Bearing Ltd. and plant visit

of different department. It was such a great experience to learn various engineering

production methods used now a days & to better correlate the theoretical knowledge with

practical observations and understandings.

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ACKNOWLEDGEMENT

As the technologically advancement will enable us to get the environment

we desire. The basic beatitude, bliss, euphoria & our endeavor to achieve

complete and perfect knowledge in the field we choose that accompany the

successful completion of any task would not be complete without the

expression of appreciation of simple virtues to the people who made it

possible. So, with reverence honor I acknowledge all those guidance and

encouragement has made successful completion of training.

I am thankful to Ms. Monika Joshi, H.R.D. Department, for her

constant cooperation and able guidance & without her support this work

would not have been so understandable.

I am also thankful to Mr. R. Jaiswal, HOD Mechanical

Department, G.V.S.E.T. who is always mentor to us.

I am also very thankful to all respected persons who have directly or

indirectly helped me in my earnest effort to accomplish this training.

Submitted ByKETAN TOSHNIWAL

6


PREFACE

The Engineering curriculum is designed in such a way that student can grasp maximum

knowledge and can get practical exposure to the corporate world in minimum possible

time. Engineering schools of today realize the importance of practical knowledge over

the theoretical base.

The research report is necessary for the partial fulfillment of engineering curriculum and

it provides an opportunity to the researcher in understanding the industry with special

emphasis on the development of skills in analyzing and interpreting practical problems

through the application of engineering theories and techniques. It is a new platform of

learning through practical experience. It gives the learner an opportunity to relate the

theory with the practice, to test the validity and applicability of his classroom learning

against real life engineering situations.

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History & Evolution of Bearing

An early type of linear bearing uses tree trunks laid down under sleds. This technology

may date as far back as the construction of the Pyramids of Giza, though there is no

definitive evidence. Modern linear bearings use a similar principle, sometimes with balls

in place of rollers.

Tapered steering head bearings for a motorcycle

The first plain and rolling-element bearings were wood, but ceramic, sapphire, or

glass were also used, and steel, bronze, other metals, ceramics, and plastic (e.g.,

nylon, polyoxymethylene, Teflon, and UHMWPE) are all common today.

A "jeweled" pocket watch uses stones to reduce friction, and allow more precise time

keeping. Even old materials can have good durability. As examples, wood bearings can

still be seen today in old water mills where the water provides cooling and lubricatio

BEARING

Definition - A bearing is a device to allow constrained relative motion between two or more

parts, typically rotation or linear movement. Bearings may be classified broadly

according to the motions they allow and according to their principle of operation as well

as by the directions of applied loads they can handle.

8


BEARING FRICTION

Plain bearings are very widely used, and use surfaces in rubbing contact. Particularly

with lubrication they often give entirely acceptable life and friction.

On the other hand, low friction bearings are often important for efficiency, to reduce wear

and to facilitate extended use at high speeds. Essentially, a bearing can reduce friction by

virtue of its shape, by its material, or by introducing and containing a fluid between

surfaces or by separating the surfaces with an electromagnetic field.

By shape, gains advantage usually by using spheres or rollers, or by forming flexure

bearings.

By material exploits the nature of the bearing material used. (An example would be

using plastics that have low surface friction.)

By fluid exploits the low viscosity of a layer of fluid, such as a lubricant or as a

pressurized medium to keep the two solid parts from touching, or by reducing the normal

force between them.

By fields exploits electromagnetic fields, such as magnetic fields, to keep solid parts

from touching.

Combinations of these can even be employed within the same bearing. An example of

this is where the cage is made of plastic, and it separates the rollers/balls, which reduce

friction by their shape and finish.

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Principles of Operation

There are at least six common principles of operation:

Sliding bearings, usually called "bushes", "bushings", "journal bearings", "sleeve bearings", "rifle bearings", or "plain bearings”.

Rolling-element bearings such as ball bearings and roller bearings.

Jewel bearings, in which the load is carried by rolling the axle slightly off-center. Fluid bearings, in which the load is carried by a gas or liquid.

Magnetic bearings, in which the load is carried by a magnetic field.

Flexure bearings, in which the motion is supported by a load element which bends.

Motions

Common motions permitted by bearings are:

Axial rotation e.g. shaft rotation Linear motion e.g. drawer Spherical rotation e.g. ball and socket joint Hinge motion e.g. door

Loads

Bearings vary greatly over the size and directions of forces that they can support.Forces can be predominately radial, axial (thrust bearings) or moments perpendicular to the main axis.

10


Global Scenario

The world Market of quality Bearing is very vast. The Big player of bearing sector are

present in U.S.A, Russia, Japan, China and eastern Europe. Some of leading bearing

manufacturer are : -

- NSK Japan

- NTN Japan

- KOYA Seiko Japan

- FAG Germany

- SKF Sweden

- NRB France

- Timken USA

There are few of leading bearing manufacturer present in India. Most of the big player are

having either technical or financial Collaboration with leading Auto Manufacturer.

International Collaboration gives Access to best technology in the world.

Global Collaboration

COMPANY COLLABORATION

FAG Bearing India FAG Germany

SKF India SKF Sweden

NRB Nadella, France

ABC Bearing Ltd. NSK Japan

TIMKEN India TIMKEN USA

BIMETAL Bearing Ltd. Clevite Corporation USA

GABRIEL India Suspension Italy

11


Indian Bearing Industry

The Indian Bearing Industry is estimated at Rs. 30 Billion approximately. The Industry

has established a highly diversified product range of around 1000 type of Bearing, having

High Volume Demand. As much as 70% of the total Demand for common varieties and

size of bearing is met by the domestic Industry, and the remaining demand of 30% is

Imported essentially for Industrial Application and special purpose. The Indian bearing

Industry can be divided in to the organized sector and un-organized sector. The organized

sector primarily caters to the Original Equipment Manufacturer (OEM) Segment,

which predominantly comprises automotive railway and other Industrial users. The

replacement market is dominated by unorganized Sector.

ORGANISED SECTOR

The organized Sector comprises about 12 big Manufacturer, who contribute to more than

50% of total turn over. Most of the big players are having either technical or financial

with International Manufacturer. International Collaboration gives access to best

technology in the world. SKF Bearing is the major player in the Indian market with the

largest market share followed by National Engineering Industry (NBC) and FAG Bearing

India the two other major players.

UNORGANISED SECTOR

The Unorganized Sector Include the Small Scale Manufacturer and Manufacturer of

Spurious Bearing. The unorganized Sector Contribute to almost 15% of Total Industry

turnover. The Unorganized Sector players have a strong regional presence and mainly

cater to the needs of the replacement market.

The direct employment provided by the above sectors is more than 12000 people. Indirect

employment for Transportation, Tools, Containers, and Packaging etc. further helps in

providing employment.

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13

INDUSTRY STRUCTURE

55%

15%

30%

Domestic Organized

Domestic Unorganized

Imports

USER SEGMENTS

45%

28%

21%

6%Automobile

General Engineering

Heavy Industries IncludingRailways

Electical Equipment &Others

DISTRIBUTION OF PRODUCTION

54%30%

6%7% 3%

Ball Bearing

Taper Roller

Cylindrical Roller

Needle Roller

Spherical Roller

MARKET DYNAMICS

60%

40%

OEM Market

Replacement Market


Threats & Limitations to Indian Market

Increasing Competition in Domestic market.

Very Low Volume of Direct Export.

Weak Marketing Linkages.

Raw Material Bank is not present.

Low level of technology used by most of manufacturing Units.

Quality of Bearing Manufactured in the Small Scale Industry (SSI) Sector

does not meet the International Quality Standard.

No Recent upgradation in Design, Technology, Process of Manufacturing

and Quality Control.

Non existence of highly skilled Man Power.

Stiff Competition from China made Bearing.

Increase in Illegal Imports.

No Entry Barrier in the cluster

Increase in Raw Material Prices.

Government Rules & Regulations - According to estimate an entrepreneur need

to interact with 14 Govt. departments to get permission for manufacturing &

exporting. Most of their time is spend in filling up forms and submitting paper as per

their requirement. Therefore Govt. rules and regulation have to be liberalized & the

role of Govt. Department should be a facilitator rather than regulator.

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Introduction

National Engineering Industries Ltd. is the largest manufacturer of Ball and Roller

Bearings, Steel Balls and Axle Boxes complete with Roller bearing in India, which are

being produced in factories at Jaipur and Newai. Bearings are manufactured for every

possible application and requirement of modern engineering industry and we continue to

develop new sizes, keeping pace with rapid advancement in the Indian engineering

industry.

NEI’s technical collaborations with the world’s leading conglomerates in the field of

Bearing technology viz. M/s NTN Corporation of Japan, M/s BRENCO incorporated of

USA have given a whole new dimension to the product range and a quality par

excellence.

NEI has already implemented modern concepts of Total Quality Management and

accredited QS9000 and TS16949 certification, NEI has also been awarded Association of

American Railroads (AAR) for AAR certificate M-1003 for Cartridge Tapered Roller

Bearing in Feb 04-05. NEI has also been awarded ISO-14001 certificate for its concern

and commitment towards a cleaner environment. NEI has successfully implemented

SAP-ERP to re-engineer and integrate business processes to conform to world class

standards.

15


Milestones

Company Established as National Bearing Company (NBC) under Technical Collaboration with Hoffman, U.K.

Ball Bearing Production Started

Railway Bearing Production Started

Company Name changed to National Engineering Industries Ltd. (Retaining NBC as trademark).

Tapered Roller Bearing Production Started under Technical Collaboration with Federal Mogul Corporation, USA

Established Research & Development Division

Established Machine Building Division

Large Diameter Special Bearing Production Started

Spherical Roller Bearing Production Started with Technical know-how from FAG-SRO

Separate Factory for Ball Bearings at Gunsi

Cartridge Tapered Roller Bearing Production Started in Technical Collaboration with BRENCO Incorporated, USA

Largest Bearing with Outer Dia. 1300mm & Weight 4.39 Tons Produced

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Technical Collaboration with NTN Corporation of Japan for Ball, Cylindrical & Spherical Roller Bearing

Modernization in Three Phases

ISO – 9001 Certificate

Technical Collaboration with M/S Izumi Kogyo Co. Ltd., Japan for Machine Retrofitting/Remanufacturing & Overhauling

Technical Collaboration with NTN Corporation, Japan for Tapered Roller Bearing & Hub Bearing

IV-Phase Modernization Started

Implemented Ist Phase of SAP-ERP Solutions

QS-9000 & ISO-14001 Certification

Ts-16949 Certification

AAR Certification M-1003 for Cartridge Tapered Roller Bearing

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Company Profile

National Engineering Industries Ltd., Jaipur was founded in the year 1946 as a pioneer

industry in the field of bearing manufacture by the renowned industrialist, late Shri B.M.

Birla, under the name of "National Bearing Company Limited." The first bearing was

manufactured in 1950 with a modest start of 30,000 bearings in 19 sizes. The company is

now manufacturing nearly 3.8 million bearings per month in over 500 different sizes

ranging from 6 mm bore to 1300 mm outer diameter and has the capacity to manufacture

bearings upto 2000 mm outer diameter. At NEI, the development of bearings is a never

ending job. With ever increasing activities and grant of industrial licenses for other vital

industries and manufacturing of Roller Bearing Axle Boxes for Railway Rolling Stock,

Steel Balls, Tapered Roller Bearings, Spindle Inserts etc., the name of the company was

changed in 1958 to "National Engineering Industries Ltd." retaining its original trade

mark NBC.

The industry is spread over 118 acres of land in Jaipur and 56 acres in Gunsi (Newai).

This is the only unit in the country manufacturing wide variety and range of bearings

such as Ball Bearings, Steel Balls, Tapered Roller Bearings, and Cylindrical Roller

Bearings & Axle Boxes for Railway Rolling Stock including Spherical Roller Bearings,

Cartridge Tapered Roller Bearings and Large Diameter special Bearings in separate fully

equipped factories. The development of National Engineering Industries Ltd., was

pioneered with a theme "Indigenisation and Self-reliance".

NBC Bearings are widely used by 2 and 3 Wheelers, Cars, Trucks, Tractors, Electric

Motors, Railway wagon, Coach and Locomotive manufacturers as Original Equipment

and Steel Mills, Heavy Engineering Plants, Bulldozers, Shovels, Tillers and Thermal

Power Plants all across the country.

Mission of Company – “Keeping Nation on the Move”

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PLANT AT JAIPUR

i.) Ball Bearing

Precision Ball Bearings from 6 mm bore to 75 mm bore diameter are manufactured with

in-process and post-process manufacturing facilities and centrally air conditioned

assembly lines with auto gauging in grinding and testing equipments. The latest advanced

techniques of manufacturing and Quality Assurance are implemented to meet the rapid

increase in demand for Quality, diversity of specifications and new types of bearings.

This Division is spread over a covered area of 14,694 Sq. Meters.

ii.) Steel Ball

Precision Steel Balls up to 25 mm diameters for NBC Bearings are manufactured on

precision grinding and lapping machines to achieve super finished surface, accuracy and

roundness as per ISO standards.


iii.) Tapered Roller Bearing

Tapered Roller Bearings are manufactured in Inch and Metric series from 15.875mm

bore to 95.25mm bore with technology obtained from Federal Mogul Corporation, USA

and NTN Corporation, Japan. These bearings are used by all major Automobile

manufacturers in the country as Original Equipment.


iv.) Railway Bearing

(a)Roller Bearing in Axle Box:

With the production of Roller Bearings and Axle Boxes since 1952, the company has

fully met the requirements of the Indian Railways by designing and developing Axle

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Boxes and bearings for fitment to Diesel Locomotive, wagon, the ICF broad and

meter gauge coaches. Over a million NBC bearings and boxes are in service with the

Indian Railways. The development of Axle Boxes and bearings for the high speed

Rajdhani Locomotive, the Yugoslavian and Egyptian Railway wagons are the

highlights of the completely indigenized design capabilities at NEI.

On date more than 100 types of Axle Boxes & Bearings have been manufactured.

(b)Spherical Roller Bearing:

The manufacturing of Spherical Roller Bearings was started in the year 1975-76 for

fitment to broad gauge and meter gauge passenger coaches.

(c) Cartridge Tapered Roller Bearing:

For fitment to the new BOX-IN Updated Wagons designed by the RDSO, NEI is the

only manufacturer in the country & largest manufacturer in the world. to indigenize

these bearings to a high percentage. Production of these bearings commenced in the

year 1984. These bearings are grease packed and require no field lubrication for a

period of 7 years.


v.) Large Diameter Bearing

NEI has the distinction of being one of the ten manufacturers of these bearings in the

world, who can manufacture large diameter bearings up to 2000 mm diameter.

The largest bearing manufactured by NEI for fitment to the Plate Mill of Rourkela Steel

Plant was 4-Row Tapered Roller Bearing measures 1300 mm diameter and weigh 4.39

tons.

The large diameter bearings are mainly manufactured out of case carburizing steel, heat

treated on special equipment and furnaces developed by NEI & grinding is done to close

tolerances on CNC machines with electronic sizing and numerical display.

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Production of these bearings started in 1975 and to date over 100 different types of

special large diameter bearings have been manufactured and successfully used, saving

considerable foreign exchange for the country.

The Large Diameter Bearings Division is spread over a covered area of 2,508 Sq. Meters.

PLANT AT GUNSI (NEWAI)

Established in the year 1980-81, as an expansion project of NEI Ltd., The factory is

equipped with fully automated grinding lines with electronic in-process & post- process

gauging and centrally air-conditioned assembly lines with auto gauging and test

equipments for quality and reliability of the products.

The plant is spread over a covered area of 7,200 Sq. Meters.

PLANT AT MANESAR

NEI has set up its third Ball Bearing manufacturing plant in Manesar, the fastest growing

industrial town of Haryana with the most advanced and sophisticated machines imported

from reputed manufacturers from Europe and Japan. This plant is equipped with state of

the art fully automated grinding lines, assembly lines and inspection equipments.

The plant is spread over a covered area of 5200 Sq. Meters.

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Research & Development

Design & Development

The design of all types of bearings is done on Pro-Engineer 3D Modeling & Analysis

Software.

Complete engineering and research with in-house facility for design development of all

types of bearings and tooling with expert advice on design, development, manufacturing,

installation and maintenance of bearings facility is available. With the signing of the

technical collaboration agreement with NTN Corporation, Japan & BRENCO Inc of

USA, the capability to offer finest engineering services in the bearing industry has

enhanced. Services of team of experienced engineers are available for selection of

bearing as per application.

Machine Building

NEI has the capability of machine building to design, develop and manufacture special

purpose CNC Grinding Lines, HT Lines, Material Handling Equipments and other

special purpose machines which have been made for its captive use to keep pace with

latest technology.

A well equipped electronic design, development laboratory with all testing facilities

supports the Machine Building Division.

Machine Building has the capability and supports the Manufacturing Divisions by

overhauling and retrofitting of the existing equipments, resulting in upgraded quality and

improved productivity.

R&D Division is spread over a covered area of 2,007 Sq. Meters.

SAP – ERP

22


In order to reengineer and integrate the Business processes for sales, production,

materials and finance, NEI has successfully implemented SAP- ERP. By use of this

Package, their processes now conform to international standard.

Quality Management System

ISO / TS 16949:2002

NEI has been awarded TS 16949: 2002 on 17th October, 2003- THE MARK OF

EXCELLENCE IN QUALITY MANAGEMENT SYSTEMS by BVQI for design,

development, manufacture & supply of Ball Bearing, Tapered Roller Bearing and

Cylindrical Roller Bearings. NEI Ltd. is the first bearing industry in India to have been

recommended for TS 16949: 2002.

This certificate is awarded only to suppliers of automobile manufacturers.

TS 16949: 2002 quality management system is based on ISO 9001: 2000 in which many

supplementary and additional requirements of automobile industries have been

incorporated.

Simplicity, effectiveness & efficiency of processes, error proofing and continuous

improvement in processes thus become the highlight of TS quality management system.

ISO 9001:2000

NEI’s Large dia. bearing division and railway bearing division which are manufacturing

Cylindrical Roller Bearings, Spherical Roller Bearings, Cartridge Tapered Roller

Bearings, Railway Rolling Stock and Spares has also been awarded to ISO 9001: 2000 on

9th October, 2003 by BVQI.

ISO 14001:1996

NEI was awarded ISO -14001 certificates by BVQI in the month of March 2000 for

Environmental Management System. NEI has done tremendous efforts in resource

23


conservation, recycling and thick plantation. The efforts at NEI have saved precious

natural resources like water, oil and power etc.

24


Collaboration

BRENCO Incorporated , U.S.A.

Since 1982-For Cartridge Tapered Roller Bearings for Railway wagons and locomotives.

NTN Corporation , Japan

Since 1985-For Ball Bearings, Cylindrical & Spherical Roller Bearings. Since 1997-For Tapered Roller Bearings.

Izumi Kinzoku Kogyo Co. Ltd., Japan

Since 1996 - For re-manufacturing, retrofitting and overhauling of grinding and super finishing machines for bearing races.

25


26


Flow of Material in Bering Industry

Material from Outside Vendor

such as Races (Inner & Outer), Cages, Retainers etc

Store House for Size Inspection

Laboratory

For Metallurgical inspection based on the norms set by R & D Department

Material is send

back to vendor

Material is send to specific departments for further Operations

The following Operations are done:

1. Hardening Or Heat Treatment

2. Rough Grinding (Face, O.D., Inner & Track)

3. Finish Grinding (Face, O.D., Inner & Track)

4. Inspection

5. Assembly

27

No


Classification of Bearing

28


Types & Features of Rolling Bearing

Name Application

Single Row Radial Ball

Bearing

1. In addition to Radial Loads, Axial Loads can be imposed in either direction.

2. Highly Suitable for applications where High Speed & Low Power loss are

required.

Single Row Angular

Contact Ball Bearing

1. They are capable of taking Radial Load & also the Axial Load in one

direction.

2. 4 contact angles 15°, 25°, 30° & 40° are available. Higher the contact angle,

higher is the Axial Load carrying capacity.

3. For Higher Speed lower contact angles are preferred.

Double Row Angular

Contact Ball Bearing

1. They are 2 single Row Angular Contact Ball Bearing mounted back to

back.

2. They have only one inner and one outer ring.

3. They can take axial load in either direction.

Self Aligning Ball

Bearing

1. The Inner Ring has 2 Raceways & Outer Ring has a single Spherical

Raceway with its centre of curvature coincident with bearing axis.

2. This has an advantage of correcting minor angular misalignment of Shaft

and Housing caused by Machining or Mounting Error.

Cylindrical Roller

Bearing

1. They have High Radial Load capacity and are suitable for High Speed.

2. Double Row bearing have high Radial Rigidity and are used primarily for

high Precision Instruments.

Tapered Roller Bearing

1. They are capable of taking high Radial Loads & also Axial Load in one

Direction.

2. Depending upon the contact angle they are divided into 3 types, Normal,

Medium & Steep Angle.

Spherical Roller

Bearing

1. Due to coincide of the centre of curvature of the outer ring raceway surface

with the bearing axis, they are also called as Self Aligning Bearing.

2. They can take Heavy Radial Load & some Axial Load in either direction.

3. They are suitable for the use where there are Heavy or Impact Load.

Thrust Bearing

1. They are capable of taking High Axial Load and some amount of Radial

Load.

2. Outer & Inner Rings are called as Washer because they seems to be as

Washer in Structure.

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Bearing Designation In NBC

Rolling bearing part numbers indicate Bearing type, Dimensions, Tolerance, Internal Construction & other related specifications.

The Digits & Indications are:-

1st Digit – Bearing Type

2nd Digit – Width or Height Series

3rd Digit – Diamete Series

Last 2 Digits – Bore Diameter

30


Inner & Outer Ring Manufacturing

Flow Chart

Forged Ring ( De-Scaled) as Raw Material

(SAE 52100 Steel)

Turning Operation

Heat Treatment

Hardness Testing

Rough Grinding

Finish Grinding

Honing & Super Finishing

Washing

Application of Rust Preventive

Ready for Dispatch to Assembly

31

(Face, Outer Diameter, Bore or Track)



Theory

Ball Bearings are generally made of High Carbon Steels, such as AISI 52100 because the

life of the bearing steel is determined by the purity of cleanliness of steel. The 52100

steel are subjected to a rigorous purification process with stringent controls in order to

meet the ever-increasing standard of cleanliness & eliminating non-metallic inclusions &

impurities. The impurities are removed through various processes such as vacuum

degassing & consumable electrode vacuum melting (CEVM). The Chemical composition

of the SAE 52100:

Element C Si Mn S P Cr

Minimum 0.98 0.15 0.25 ---- ---- 1.30

Maximum 1.10 0.35 0.45 0.025 0.025 1.60

Oxygen Content – Not more than 15 ppm

The Turning operations are divided into various lathe Operations viz. O.D., face, track &

Bore. All these operations are done on production lathe machines.

The Hardening of steel is achieved by heat treatment process in which the steel

microstructure is manipulated by cycles of heating & quick cooling to obtain the

optimum hardness range for steel – usually on the order of 60 to 64 on Rockwell C

Hardness Scale. When slowly quenched it would form Austenite & Pearlite which is a

partly hard and partly soft structure respectively. Hardening of steel requires a change in

structure from Body Centered Cubic Structure found at room temperature to Face

Centered Cubic Structure found in Austenite Region. When Steel is suddenly Quenched

Martensite is formed which is extremely strong and If steel is Quenched slowly then

Pearlite is formed which is extremely Soft.

32


The Next stage is grinding, in order to give the rings the right form and dimension. The

operations occur in following Order:

Face Grinding – It is the first operation for both inner & outer rings. Both faces

are ground simultaneously to give the final width.

Outside / Center less Grinding – Outside diameter of inner ring is ground to final

dimension in center less grinding machine.

The final machining operations are carried out on parallel lines of grinding and

finishing machines. Inner Rings have the bores & raceways ground while Outer

Rings have the only the raceway ground. These operations are carried away by

form dressed grinding wheels.

After grinding Operation, Honing is done.

After Honing the rings are thoroughly washed with water based cleaning medium so

Rings get perfectly cleaned before Assembly is done.

33


Spherical Ball Manufacturing

Flow Chart

Input Wire Rod as Raw Material

(SAE 52100 Steel)

Shearing & Handling Operation

On Ball Header Machine

Deburring on Vibro Benz Machine

Lushing of excess material after the Ball forged in Cold Header

Heat Treatment of Ball

Grinding of Ball in Rotary Grinding Machine (Flashing Machine)

Lapping in Ball Lapping Machine

Inspection for checking Hairline Cracks

Lapping of Balls in Tumbling Barrel

Magnetic Crack Testing

Washing


Packing & Dispatch to Assembly Line

Theory

34


The Raw Material used (SAE 52100) for manufacturing of balls is a specially formulated

grade of Steel Wire. The Material is Supplies either by wire or rod. It is then cut to length

& width.

The wire or rod is then fed through a header. This cold forged process produce “slugs” at

an incredibly high speed. Wire is fed from decoilers into cold heading machines where it

is cut into blanks and then pressed into balls between hemispherical dies.

The flash around the balls produced during pressing is removed by filing plates in

deburring machines.

These rough shaped balls have a ring around the middle. The next process is to remove

this ring by machining in rill-filing machine, equipped with one fixed and one rotating

cast iron rill-plate. Concentric grooves in the plate ensure that the whole ball surface is

machined to same extent and thus a spherical form is achieved

Final inspection for size, form and surface finish is carried out on a sample basis by

means of high resolution microscopes and other precision equipment because a tiniest

deviation even of the order of 1 Å (10-10 m) in the roundness of bearing element can have

an impact on bearing quality.

The balls are then cleaned and packed ready for bearing assembly operation

35


Cage Manufacturing

Flow Chart

Raw Material

(Narrow width Cold Rolled Sheet IS 4397)

Blanking & Punching

Forming (Pocketing)

Inspection & Batch Checking

Shot Blasting/Vibro

Assembly Line

Theory

The cages for various bearing sizes are manufacture from Cold Rolled (C.R.) & Cold

Annealed narrow width sheets IS 4397. The C.R. sheet is converted in the cage in Press

Machine in Successive Operations:

Blanking, Punching, Forming (Pocketing) rivet holes and visual inspection is carried for

any deformity.

36


Rivet Manufacturing

Flow Chart

Raw Material

(Wire EN 8 or EN 9)

Heading in Ball Header

Deburring in Vibro Benz Machine

Rust Preventive Oiling

Assembly Line

Theory

The Rivets are manufactured from wire rods. The Wires are cut in requires sizes in Rivet

Header machine, then in Vibro Machine it is Super – Finished.

There is no Grinding operation involved.

37


Ball Bearing Assembly Line

Flow Chart

Put Inner in Outer

Insert Balls

Put Retainers

Put under Riveting Machine

Riveting

Washing

De-Magnetizing

Inner & Outer Diameter Inspection Machine

Radial Clearance Testing Machine

Washing

Double side Vibration (Noise) Testing Machine

Laser Aching Machine

Application of Anti Rust

Packaging of Bearing in Pillow Wrapping Machine & Ready to Dispatch

Theory

38

Cage Rivet Outer Inner Ball


Finally the rings, balls & Cage which have been manufactured in different locations come

together for semi – Automatic or Automatic Assembly.

Raceways & Rings are Optically Inspected separately prior to assembly. By selecting

suitable combinations of ring & ball sizes the required internal clearance is obtained.

Balls are fed between the rings and spaced equally before the two cage halves are fitted

and riveted together.

After washing, the final inspection sequence starts which consist of number of checks

such as running accuracy, vibration level, outside and bore diameters and radial clearance

of bearings.

The bearings are then automatically washed, coated with preservative, greased and fitted

with seals or shields before being packed.

39


40


Inner & Outer Ring Manufacturing for

Spherical, Cylindrical & Tapered Roller Bearing

Flow Chart

Forged Ring (De-Scaled) as Raw Material

(SUJ 2 Steel or SC/SCM/SNCM Steel)

Turning Operation

Heat Treatment

Hardness Testing

Rough Grinding

Finish Grinding

Honing & Super Finishing

Washing


Ready for Dispatch to Assembly

41




Theory

The contact surfaces of the bearing rings and rolling elements are subjected to repeated

heavy stresses, so they must maintain high precision and rotational accuracy. To

accomplish this, the rings and rolling elements must be made of a material that has high

hardness, resistant to rolling fatigue, wear resistant and has good dimensional stability.

High carbon chromium bearing steel (SUJ 2) deep hardened by the hardening method &

case hardening steel (SC/SCM/SNCM) with a hardened carburized outer layer are used

for the rings and rolling elements of standard bearings.

The most widely used and most suitable materials for rolling bearings are high carbon

steels. The most commonly used of these steels is SUJ2. For bearings with large cross

section dimensions SUJ3 or SUJ5 having good hardening properties are used. NBC uses

high carbon steel for almost all of spherical roller & cylindrical roller bearings.

For case hardening steel; Chrome Steel (SCr), Chrome Molybdenum Steel (SCM) and

Nickel Chrome Molybdenum Steel (SNCM) are used because of its combination of a

hard surface layer which has been carburized and hardened to an appropriate depth, and a

relatively pliable inner core, case hardening steel has excellent efficiency against shock

load. NBC uses case hardening steel for almost all of tapered roller bearings.

Since the life of the bearing steel is determined by the purity of cleanliness of steel the

above grade steels are low in non-metallic impurities & low in oxygen content because

they are refined by a vacuum degassing process & outside hearth smelting process.

The Chemical compositions of above steels are:

42


Specification Elements C Si Mn P S Ni Cr Mo

SUJ 2Minimum 0.95 0.15 ---- ---- ---- ---- 1.30 ----

Maximum 1.10 0.35 0.50 0.025 0.025 ---- 1.60 ----

SUJ 3 / SUJ 5Minimum 0.95 0.40 0.90 ---- ---- ---- 0.90 0.10

Maximum 1.10 0.70 1.15 0.025 0.025 ---- 1.20 0.25

SCr 420Minimum 0.18 0.15 0.60 ---- ---- ---- 0.90 ----

Maximum 0.23 0.35 0.85 0.030 0.030 ---- 1.20 ----

SCM 420Minimum 0.18 0.15 0.60 ---- ---- ---- 0.90 0.15

Maximum 0.23 0.35 0.85 0.030 0.030 ---- 1.20 0.30

SCNM 420 /

SCNM 815

Minimum 0.15 0.15 0.35 ---- ---- 2.00 0.50 0.15

Maximum 0.21 0.35 0.65 0.030 0.030 4.00 0.90 0.30

The Turning operations are divided into various lathe Operations viz. O.D., face, track &

Bore. All these operations are done on production lathe machines.

The Hardening of steel is achieved by heat treatment process in which the steel

microstructure is manipulated by cycles of heating & quick cooling to obtain the

optimum hardness range for steel – usually on the order of 60 to 64 on Rockwell C

Hardness Scale. When slowly quenched it would form Austenite & Pearlite which is a

partly hard and partly soft structure respectively. Hardening of steel requires a change in

structure from Body Centered Cubic Structure found at room temperature to Face

Centered Cubic Structure found in Austenite Region. When Steel is suddenly Quenched

Martensite is formed which is extremely strong and If steel is Quenched slowly then

Pearlite is formed which is extremely Soft.

43


The Next stage is grinding, in order to give the rings the right form and dimension. The

operations occur in following Order:

Face Grinding – It is the first operation for both inner & outer rings. Both faces

are ground simultaneously to give the final width.

Outside / Center less Grinding – Outside diameter of inner ring is ground to final

dimension in center less grinding machine.

The final machining operations are carried out on parallel lines of grinding and

finishing machines. Inner Rings have the bores & raceways ground while Outer

Rings have the only the raceway ground. These operations are carried away by

form dressed grinding wheels.

After grinding Operation, Honing is done.

After Honing the rings are thoroughly washed with water based cleaning medium so

Rings get perfectly cleaned before Assembly is done.

44


Roller Manufacturing

Flow Chart

Input Bar as Raw Material

(SUJ 2 Steel)

Turning Operation on Production Lathe

Deburring

Lushing of excess material

Rough Grinding of Rollers

Heat Treatment of Rollers

Finish Grinding of Rollers

Lapping in Roller Lapping Machine

Inspection for checking Hairline Cracks

Lapping of Rollers in Tumbling Barrel

Magnetic Crack Testing

Washing


Dispatch to Assembly Line

45


Theory

The Raw Material used (SUJ 2 Steel) for manufacturing of rollers is a specially

formulated grade of Steel. The Material is Supplies by rod. It is then cut to length &

width on Production Lathe.

For Spherical Rollers or Tapered Rollers, The rod is then fed through a header. This cold

forged process produce “slugs” at an incredibly high speed. Rod is fed from decoilers

into cold heading machines where it is cut into blanks and then pressed between

hemispherical dies or conical dies. For Cylindrical Rollers the above procedure is not

done.

The flash around the rollers produced during pressing is removed by filing plates in

deburring machines.

These rough shaped spherical rollers have a ring around the middle. The next process is

to remove this ring by machining in rill-filing machine, equipped with one fixed and one

rotating cast iron rill-plate. Concentric grooves in the plate ensure that the whole roller

surface is machined to same extent and thus a spherical form is achieved

The next process for Rollers is grinding in which rollers are grind in the order: Face, O.D,

and I.D. The grinding process is done in two phases; one prior to Heat Treatment (Rough

Grinding) & one after the heat treatment process (Finish Grinding).

Final inspection for size, form and surface finish is carried out on a sample basis by

means of high resolution microscopes and other precision equipment because a tiniest

deviation even of the order of 1 Å (10-10 m) in the roundness of bearing element can have

an impact on bearing quality. The rollers are then cleaned and dispatched for bearing

assembly operation

46


Cage Manufacturing

Flow Chart

Raw Material

(Narrow width Cold Rolled Sheet IS 4397)

Blanking & Punching

Forming (Pocketing)

Inspection & Batch Checking

Shot Blasting/Vibro

Assembly Line

Theory

The cages for various bearing sizes are manufacture from Cold Rolled (C.R.) & Cold

Annealed narrow width sheets IS 4397. The C.R. sheet is converted in the cage in Press

Machine in Successive Operations:

Blanking, Punching, Forming (Pocketing) rivet holes and visual inspection is carried for

any deformity.

47


Roller Bearing Assembly Line

Flow Chart

Put Inner in Outer

Insert Rollers & Cage

Put under Pressing Machine

Pressing

Washing

De-Magnetizing



Washing





Theory

48

Cage Outer Inner Rollers


Finally the rings, Rollers & Cage which have been manufactured in different locations

come together for semi – Automatic or Automatic Assembly.


suitable combinations of ring & Rollers sizes the required internal clearance is obtained.

Rollers are fed into the cage which are together fed in between the Outer & Inner

Raceway & are fitted together through pressing.



of bearings.

The bearings are then automatically washed, coated with preservative, greased and fitted

with seals or shields before being packed.

49


Railway Bearing Assembly LineFlow Chart

Put Spacer Ring in Outer

Insert Cage & Rollers Assembly

Washing

Insert Seal Ring or Seal Caps

Put End Caps

De-Magnetizing



Washing





Assembly with Sealing Rings

Assembly with Lamellar Rings

50


Theory

Finally the Outer rings, Spacer Rings & Rollers & Cage Assembly which have been

manufactured in different locations come together for semi – Automatic or Automatic

Assembly.


suitable combinations of Outer & Inner rings, the required internal clearance is obtained.

Spacer Ring is inserted between the Rollers & Cage Assembly to avoid interaction

between them.



of bearings.

The bearings are then automatically washed, coated with preservative, greased before

being packed.

Cylindrical roller bearings are used on wagons, BEML coaches and engines. Spherical roller bearings are used on ICF coaches, some wagons and engines. Tapered roller bearings are only used on engines.

51


52


Heat Treatment Process

Chugai – Ro Heat Treatment Furnance

Hardening Procedure for High Carbon Steel ( C – 0.9% to 1.10%)

Process Hardening Quenching TemperingAir

Cooling

Procedure

Heat the Furnace850-870O C

Fast cooling 600 C – Oil Quenching1800C – Salt Bath

Furnace Heating 1650-1800C

Cool at Room Temperature

Hardness ------ 62 – 66 HRC 60 – 64 HRC ------

Time 35-60 min.According to the job

5-15 min. 150 min. ------

53


Hardening Procedure for LC Steel (Low Carbon Steel)

Process Carburizing Hardening Quenching Tempering

Procedure

Carbon Furnace heating at 9400 C - 9500 C

Furnace temperature at 8500 C – 8700 C

Fast cooling 600 C –for oil quenching only

Heat the Furnace at 1650 C-1800 C

Hardness .200 - .250 ------ 60 – 64 HRC 52 – 62 HRC

Time 8 – 10 hours 35-60 min.According to the job.

5-15 min. 120-180 min.

Salt Bath Furnace

54


Heat Treatment

Raw Material(Carbon Steel)

Carburizing

(Carbon Shield Layer increases Hardness)(10 – 12 hrs.) (940 0C) (GC Furnace)

Hardness I

(Revolving Furnace)(920 0C) (Time Dependent on Job)

Annealing(6 hrs.) (650 0C)

Shot Blasting

Hardening II(Revolving Furnace)

(820 0C) (Time Dependent on Job)

Sub-Zero Treatment(-60 0C) (Increases Toughness)

Tempering(160 0C) (4 hrs.)

Shot Blasting

(Wheel Abrator)

Hardness Inspection

(60 HRC)

55


Conclusion

This report describes the NBC bearing industry and its technology. The industry is spread

over 118 acres of land in Jaipur and 56 acres in Gunsi (Newai).

This is the only unit in the country manufacturing wide variety and range of bearings

such as Ball Bearings, Steel Balls, Tapered Roller Bearings, Cylindrical Roller Bearings

& Axle Boxes for Railway Rolling Stock including Spherical Roller Bearings, Cartridge

Tapered Roller Bearings and Large diameter special Bearings in separate fully equipped

factories.

NEI has set up its third Ball Bearing manufacturing plant in the fastest growing industrial

town of Manesar in Haryana. The plant is having a covered area of 5200 sq. meters. with

the most advanced and sophisticated machines imported from reputed manufacturers

from Europe and Japan .

It has been long pursued policy and commitment of National Engineering Industries

Limited (NEI) to adhere to highest standards of integrity – professional and financial –

and business ethics in the operation of its business. We believe that this organization has

been handed to us by the various stakeholders in "trust” and we as professional managers

are the "trustees" of those stakeholders. It is therefore our responsibility to ensure that the

organization is managed in a manner that protects and furthers the interests of our

stakeholders.

56

Documents

Training Report of NBC Bearing