1A presentation

On

NATIONAL BEARING COMPANY

CHIRAG JOSHI

BY

Contents

About NBC

Introduction to Bearing

Types of Bearing

Ball Bearing

Construction of Ball Bearing

Manufacturing Process of Ball Bearing

Features of Ball Bearings

Types of Load and Load Equations

Applications of Ball Bearings

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Company Profile

NBC Bearings is the product of National Engineering Industries Limited(NEI), a part of the CK Birla Group, which manufactures a wide range ofbearings for the automotive, industrial and railways

NEI manufactures bearings in about 1000 different sizes

It has the capacity to develop bearings from 10 mm bore to 2000 mmouter diameter.

NBC’s current capacity is to make 100 million bearings annually across itsthree plants (Jaipur, Newai, Manesar). NEI aims to double the productioncapacity in next seven years

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Introduction to Bearings

The term "bearing" is derived from the verb "to bear"; a bearing being a

machine element that allows one part to bear (i.e., to support) another

A bearing is a machine element that constrains relative motion to only the

desired motion, and reduces friction between moving parts

Objective of bearing is to provide relative positioning and rotational

freedom while transmitting a load between two parts.

It needs a good support to ensure stability and frictionless rotation.

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Types of Bearing 5

Ball Bearing

Tapered Roller Bearing

Cylindrical Roller Bearing

Spherical Rolling Bearing

Ball Bearing

A ball bearing is a most common type of rolling-element bearing that usesballs to maintain the separation between the bearing races

Precision Ball Bearings from 6 mm bore to 75 mm bore diameter aremanufactured in NBC

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

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Tapered Roller Bearing

Can take large axial forces as well as being able to sustain large radialforces.

Based on the observation that cones that meet at a point can roll overeach other without slipping.

Generally separable, which means the cone assembly, consisting of theinner ring with roller and cage

Precision Ball Bearings from 17 mm bore to 100 mm bore diameter aremanufactured in NBC

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Tapered Roller Bearing Cont.… 8

Cylindrical Roller Bearing

Have a high radial load capacity and are suitable for high speeds

Precision Ball Bearings from 20 mm bore to 75 mm bore diameter are

manufactured in NBC

Cylindrical bearings provide the highest possible radial load capacity

compared to other roller bearing types

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Spherical Roller Bearing

Spherical roller bearings are self-aligning bearings designed for heavy

radial loading.

Precision Ball Bearings from 50 mm bore to 200 mm bore diameter are

manufactured in NBC

A spherical roller bearing is a rolling-element bearing that permits rotation

with low friction, and permits angular misalignment

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Assembling of Ball Bearing 11

Rolling vs. Sliding Friction 12

Manufacturing Process 13

Ball forgingTube extrusion

Heat Treatment

Ball manufacturing

Race Grinding

Assembly

Finished goodsWarehouse &

Shipping

Bought out component

Turning

Manufacturing Process Cont.…

CARBURIZATION

Carburizing is a is a heat treatment process in which iron or steel absorbs carbon

liberated when the metal is heated in the presence of a carbon bearing material,

such as charcoal or carbon monoxide, with the intent of making the metal harder.

The carburizing is performed 940º to 980ºc in rotary hearth furnace with time of

10hrs. But carburizing is done for only cup and cone with Air: LPG =10:1 (Endo

Gas).

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Manufacturing Process Cont.…

QUENCHING

Quenching is a process of cooling a metal at a rapid rate. This is most often done

to produce a marterialistic transformation. In ferrous alloys, this will often produce

a harder metal, while non-ferrous alloys will usually become softer than normal.

In NBC Oil is used in the quenching process and the oil is kept at a temperature of

250C. Agitator is used to stir the oil in the oil quenching tank.

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Manufacturing Process Cont.… 16

Stress Reliving

Interesting Facts

If you were to file down onto a ball bearing, you would wear out the file

before you would wear out the bearing!

If you were to expand a 1-inch ball to equal the size of planet Earth, the

ball would be rounder than the actual Earth

The Hubble telescope, weather satellites and even the Mars Space Rover

all use bearings.

When using outer race rotation, you are reducing your bearing lifespan by

20%

70% of bearing failures are from improper lubrication

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Features of Ball Bearing

Can be used under wide range of temperature

Internationally available and available.

Maintenance, replacement, inspection are easy

Cheap

Have great rigidity and are robust

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Applications of Ball Bearing 19

In horology, the company Jean Lassale designed a watch movement that

used ball bearings to reduce the thickness of the movement

Aerospace bearings are used in many applications on commercial, private

and military aircraft including pulleys, gearboxes and jet engine shafts

Skateboard wheels each contain two bearings, which are subject to both

axial and radial time-varying loads

Types of Bearing Load

Bearings typically have to deal with two types of load:

Radial Load

Axial Load (Thrust)

RADIAL LOAD act at right angles to the shaft (bearing's axis of rotation)

AXIAL LOAD (Thrust) acts parallel to the axis of rotation.

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Types Of Bearing Load Cont.… 21

The bearings in the electricmotor and the pulley picturedabove face only a radial load.In this case, most of the loadcomes from the tension in thebelt connecting the twopulleys.

The bearing above is like theone in a barstool. It is loadedpurely in thrust, and the entireload comes from the weight ofthe person sitting on the stool.

The bearing above is like theone in the hub of your carwheel. This bearing has tosupport both a radial load anda thrust load. The radial loadcomes from the weight of thecar, the thrust load comes fromthe cornering forces when yougo around a turn.

Load Equations

Relative axial load = (Fa/ZDw )

Fa = Axial Force

Z = Number of balls

Dw = Ball Diameter

Relative radial load = (MF/R)

M = Torque

R = Radius

F = Load Connection Factor

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F = Load Connection Factor

Single Chain Drive 1.00

Timing Belt Drive 1.10

Spur, Helical Gear 1.25

Double Chain Drive 1.25

V-Belt Drive 1.50

Flat Belt Drive 2.50

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