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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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