SOUTH WESTERN RAILWAYS

CENTRAL WORK SHOPS

An
INTERNSHIP REPORT ON
“WHEEL AND AXLE SHOP”
Submitted by
Charan Kumar B (USN:1GC14ME013)
Krishna P V (USN:1GC14ME033)
Mohan B K (USN:1GC14ME057)
Mohan Kumar M (USN:1GC14ME058)
Shivaraj Kumar M V (USN:1GC14ME089)

(Attended 5 th February 2018 to 14 th February 2018)

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 ACKNOWLEDGEMENT

We are very happy to submit this training report which is

prepared in connection with individual training CENTRAL
RAILWAY WORKSHOPS, MYSURU SOUTH from 05-02- 2017 to
15-02-2017. We would like to express our sincere thanks to
management of CENTRAL RAILWAY WORKSHOPS, MYSURU
SOUTH for allowing us to have industrial training here and we
are very thankful for the opportunity.

We wish to express our deep sense of gratitude to all the staffs

and executive of CENTRAL RAILWAY WORKSHOPS, MYSURU
SOUTH who helped us in knowing the technical points through
demonstration and length discussion.

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 LIST OF CONTENTS

1. INTRODUCTION 3-8
2. WHEEL SHOP 9 - 11
3. WHEELS 12 - 17
4. AXLES 18 - 19
5. INSPECTION PROCEDURE IN THE WORKSHOP 20 - 22
6. NORMAL REPAIR OF WHEELS 23 - 24
7. REPLACEMENT OF AXLES 25
8. REPLACEMENT OF WHEELS 26
9. BORING OF NEW WHEELS 27
10.PRESSING OF WHEEL ON AXLE 28
11.ULTRASONIC TESTING OF WHEEL AND AXLES 29
12.STAMPING OF PARTICULARS 30 - 31
13.WHEEL DEFECTS 32 - 42
14.BEARING SECTION 43 - 45
15.LUBRICATION 46
16.INSPECTION OF OTHER SPHERICAL BEARING
COMPONENTS 47 - 48
17.DISMOUNTING OF BEARING 49 - 50

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 CHAPTER: 1 INTRODUCTION

1.1 HISTORY OF INDIAN RAILWAY

Indian Railways is an Indian state-owned enterprise, owned and operated by the
Government of India through the Ministry of Railways. It is one of the world's largest
railway networks comprising 115,000 km (71,000 mi) of track over a routeof 65,436 km
(40,660 mi) and 7,172 stations.

Fig.1.1 Logo of Indian Railway

Indian Railways is the world's seventh largest commercial or utility employer, Railways
were first introduced to India in the year 1853 from BORIBUNDER to THANE a distance of
34kms. In 1951 the systems were nationalized as one unit, the Indian Railways, becoming
one of the largest networks in the world. IR operates both long distance and suburban rail
systems on a multi-gauge network of broad, meter and narrow gauges. It also owns
locomotive and coach production facilities at several places in India and are assigned codes
identifying their gauge, kind of power and type of operation. Its operations cover twenty
nine states and seven union territories and also provides limited international services with
over 1.307 million employees as of last published figures in 2013. As for rolling stock, IR
holds over 239,281 Freight Wagons, 62,924 Passenger Coaches and 9,013 Locomotives (43
steam, 5,345 diesel and 4,568 electric locomotives). The trains have a 5 digit numbering
system and runs 12,617 passenger trains and 7421 freight trains daily.

1.2 HISTORY OF CENTRAL RAILWAY WORKSHOP,MYSORE

The Railway Workshop at Mysore was established as a Base Workshop of the erstwhile
Mysore State Railway in 1924. Consequent to the transfer of few sections like Bangalore –
Harihar and Yeshvanthapur –Hindupur to the State Railways, the workshop was expanded
to the present form in 1938 with the task of maintaining the MG Rolling stock in the then
undivided Mysore and Guntakal Divisions. With the formation of integrated Southern
Railway in 1951this workshop became part of Southern Railway.

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 Progressive dieselization of the MG sections coupled with the policy of uni-gauge
contributed to the steady decline of MG load arising. The legacy of “Skill and dedication” of
the Mysore workshops was not destined to be abruptly reduced to redundancy. This
Workshop was converted to BG coach POH shops during the year 1993 and started POH of
BG coaches from August 1994 onwards. This work shop became the part of South Western
Railway from 01.04.2003 onwards mainly dealing with the POH/IOH of BG coaches.
Present activities of the workshop (including RSP work)
• Periodic Overhauling of all types of BG Coaches.
• Refurbishment of coaches.
• Intermediate Overhauling (IOH) of Bogies.
• Manufacturing of Toy Train.
• Manufacturing of Composite Brake Blocks.

1.3 SHOPS INSIDE WORKSHOP, MYSORE

1. Wheel Shop
2. Carriage lifting
3. Bogie Repair Shop
4. Heavy Corrosion and Repair
5. Carriage Body Repair
6. AC Shop
7. Machine Shop
8. Composite Brake Block
9. Air Brake Shop
10. Paint Shop
11. Mill Wright
12. Train Lighting
13. Alternator Section
14. Process Control Organization
15. Trimming Shop

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1.4 RAILWAY ZONES AND THEIR HEAD QUARTERS

Table.1.1 Railway Zones and Their Head Quarters

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1.5 VARIOUS RAILWAY ZONES AND THEIR HEAD QUARTERS

1.6 RAILWAY ORGANISATION SET UPS

Indian Railways does the main business of transporting men and material from one place to
another all over the country with the MOTTO OF:
SAFETY
SEURITY
PUNCTUALITY and
CLEANLINESS

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It stands second largest in the world. It stands first largest in Asia. For easy control and in order
to ensure effective working it is divided into 17 zones and sub-divided into 68 divisions.

1.7 ZONAL LEVEL ORGANIZATION SETUP

1.8 DIVISIONAL LEVEL ORGANIZATION SETUP

1.8 PRODUCTION /MANUFACTURING UNITS

COACHES
Integral Coach Factory,
Perambur Rail Coach Factory
Kapurthala Bharat Earth Movers Limited,Bengaluru
New units being under development at Kacharapara, Kalmasery(KERALA) and,
Raibareli.(UP)

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WHEEL AND AXLE
Rail Wheel Factory, Yelhanka
Rail PahiyaKarkana, Chapra, Bihar.
Rail springs karkana,Gwalior

LOCOMOTIVES
Chittaranjan Locomotive Works, Chittaranjan (West Bengal)
Diesel Loco Works, Varanasi (Uttar Pradesh)
Diesel Loco Modernization Works, Patiala. (Punjab)

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 CHAPTER: 2 WHEEL SHOP
2.1 INTRODUCTION
The movement of rolling stock on the track is possible only with the help of wheels. The
complete wheel set is shown in the Fig 2.1with the assembly components.

WHEEL SET
A complete unit comprising an axle and two complete wheels together with any
gear wheels, brake discs, etc, but without axle bearings and their end caps,
spacers, seals and other associated fittings

COMPONENTS OF A WHEEL SET

A wheel set is an assembly mainly of two components:
1) Wheel discs(solid) on both sides of the axle
2) An axle to hold these wheel discs in position

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2.2 WHEELSHOP LAYOUT

2.3 FACILITIES AVAILABLE IN WHEEL SHOP

1. EOT crane 5 tones
2. Wheel profiling lathe
3. Axle journal turning and burnishing lathe
4. Hydraulic wheel press with facility for mounting pressure diagram
5. Hydraulic wheel press off machine
6. Axle turning lathe
7. Vertical turning lathe
8. Axle end drilling machine

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 CHAPTER: 3 WHEELS
3.1 INTRODUCTION
• Railway wheel is assembly of two wheels fixed to the axle by interference fit and they rotate
along with the axle, without any independent relative movement as in the case of other
automobile wheels.
• These wheels are provided with flange towards the inner side, which guide the wheels to
travel on the rails and does not allow it to fall down from the rails.

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3.3PARTS OF WHEEL
The wheel is better understood by dividing it into the following parts
• Hub
• Disc
• Tyre

HUB
• Hub is the centre portion of the wheel, where the wheel is fixed to the axle by means of
interference fit.
• Thickness of the wheel is maximum at the hub portion.
• UT details is marked on the Hub

DISC
• Disc is the portion of the wheel between the hub and the tyre.
• This portion is the thinnest portion of the wheel as it does not come in contact with rail nor it
is coming in contact with the axle.

TYRE
• Tyre is the portion in contact with the rail, which wears out in service.
• The profile of the tyre is significant for safe running of the trains. Taper is given on the tread
to have higher diameter near the flange and lower diameter at the outer edge, to facilitate
curve negotiation.

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The solid wheel disc is manufactured as per IRS Specification No. R - 19/ 93 Pt. II and drawing
no. W/WL/1660

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3.4WORN WHEEL PROFILE
80 % of the track in Indian Railways is having rails which are already worn in service. Standard
wheel profile running on these tracks tend to wear to a specific profile within short time itself,
and further wear from this profile is very slow. Hence if the wheels are turned initially to this
worn wheel profile, it will increase the wheel life by avoiding frequent reprofiling.

The worn wheel profile is made standard for all the wheels in Indian railways as the standard
wheel profile is found uneconomical with lesser kilometers being run by the wheels within
condemnation.

3.2 STEP SIZES OF WORN WHEEL PROFILE

The step sizes of worn wheel profile are
• 29.4 mm thick flange (Standard )
• 25.0 mm thick flange
• 22.0 mm thick flange
• 20.0 mm thick flange. Further to reduce the metal removal during tyre turning, intermediate
worn wheel profile based on the flange thickness is introduced.

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 CHAPTER: 4 AXLES
4.1 INTRODUCTION
An axle is a component of a wheel set to hold the wheel discs in position. The axle box is also
mounted on the journal of the axle.

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CHAPTER: 5 INSPECTION PROCEDURE IN THE
WORKSHOP

5.1 WHEEL FLOW DIAGRAM

5.2 PRE-INSPECTION OF WHEELS IN THE WORKSHOP

During pre-inspection of incoming wheels, the wheel-set is inspected for assessing the
condition of the components. Following measurements are carried out on all the wheels,
received in shop for repairs.

MEASUREMENT OF A WHEEL GAUGE (DISTANCE BETWEEN TWO

WHEELS FLANGES ON THE SAME AXLE)
The distance between two wheel flanges on the same axle should be 1600 mm + 2/-1 mm. This
measurement should be taken at three locations apart with the help of an adjustable pi gauge.

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If wheel gauge is not within permissible limits, then the wheel disc (s) have to be pressed off
and then pressed on.

MEASUREMENT OF WHEEL DIAMETER (TREAD DIAMETER)/WHEEL

FLANGES
The wheel diameter is measured with the help of a trammel gauge with a least count of 0.5
mm. on both sides. However, a gauge with a least count of 0.1 mm. is recommended as the
measurement of a diameter would be more accurate with this gauge.
The difference in tread diameter of the two wheels on the same axle should not exceed 0.5
mm after tyre turning. There is no 'In service' limit for this variation and rejection shall be
decided by tyre defect gauge.
During last shop issue the wheel is to be turned to RDSO SK-91146. The profile is to be turned 1
mm above the condemning limit groove. The maximum diameter and last shop issue size for ICF
type wheels are given below:

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INSPECTION OF WHEEL FLANGES

The flanges on both sides of a wheel set are checked with the help of a profile gauge to
measure the height and thickness of flanges. Accurate measurement of flange height and flange
thickness is not possible with the profile gauge. It is, therefore, recommended to use a wheel
profile gauge with which accurate measurement of flange height and flange thickness to the
extent of 0.1 mm can be made.
After recording the diameters of wheels and wheel flange measurements, the wheel set is
nominated for necessary repairs.

5.3 PRE-INSPECTION OF AXLE Axle

journals should be thoroughly cleaned for inspection to detect flaws, pitting, ovality, taper,
ridges etc. Each axle should be ultrasonically tested for detecting internal flaws and defects as
per the code of procedure issued by RDSO. Axles found flawed, pitted or with under size
journals should be replaced.

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 CHAPTER: 6 NORMAL REPAIR OF WHEELS
If all the components are within the acceptable range of limits, these are taken directly for
wheel profiling and servicing of roller bearings, if not normal repair procedure is carried out.

6.1 WHEELS REQUIRING REPLACEMENT OF AN AXLE (RA WHEELS)

The wheel is taken for replacement of an axle for the following :

 A bent axle,
 Dimensional deviations on a journal / wheel seat
 Axle having groove marks in the middle due to rubbing of a pull rod,
 Dents, corrosion, pitting marks on the surface of the axle
 Axles found flawed in the ultrasonic flaw detection test

6.2 WHEELS REQUIRING REPLACEMENT OF SOLID DISCS (RD WHEELS)

The wheel is taken for replacement of discs if found
 It is not possible to turn the wheel to the last shop issue size
 There is a rejectable defect as per CMI-K003.

6.3 REPAIR PROCEDURES FOR DIFFERENT CATEGORIES OF WHEELS

Detailed procedure for carrying out repairs to different categories of wheel sets is described
below: NORMAL REPAIR OF WHEEL SETS Normal repair wheels are of two categories.
a. With roller bearings mounted
b. With roller bearings removed
THE ACTIVITIES INVOLVED IN NORMAL REPAIR WHEELS ARE AS FOLLOWS:

 Pre-inspection of incoming wheels.

 Drop axle boxes, clean and inspect axle boxes. If required, repair them.
 Carry out Ultrasonic Flaw detection test of axle.
 If required, dismount roller bearings from journals. (In any case dismount roller bearings in
alternate)
 If the wheels are sent for re-profiling without dismounting roller bearings from the journals,
special protective covers should be fitted on the bearings on either side of a wheel to avoid
entry of chips / dust or damage to the bearing during machining.
 Machine wheel profiles to the prescribed dimensions. The wheel tread should be checked
and machined to the worn wheel profile and machining standard N11 to IS: 3073. (see figure
10.4 for worn wheel profile)
 Clean roller bearing and assemble components in position, if not dismounted

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 Inspect roller bearing and assembly in position.

 Check radial clearance and confirm it to be within permissible limits.

 Pack fresh grease

 Mount cleaned and inspected axle boxes.

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 CHAPTER: 7 REPLACEMENT OF AXLES
The activities involved in replacement of an axle are as follows:

 PRESSING OFF A REJECTED AXLE FROM A WHEEL

The wheel is taken on the wheel press for separating the rejected axle from the wheels.

 MACHINING OF NEW AXLES

New axles should be machined to the correct drawing dimensions. Journal, journal fillets and
shoulders should be finished smooth, concentric and without ridges, burrs or chatter marks.

 INSPECTION OF MACHINED AXLES

A machined axle should be inspected for dimensional accuracy with the help of a micrometer
with least count of 0.01 mm. Journal diameters should be measured at three points along the
length of journals both on the vertical and horizontal axis. The ovality and taper must not
exceed the limits prescribed in the drawing. Ultrasonic flaw detection test is carried out for
cracks. Surface finish of the axle on journals, wheel seat
and middle portions should be checked with the help of a surface finish tester and the
prescribed limits are as below:

 MACHINING OF SERVICEABLE WHEEL DISC

The serviceable wheel discs are re-bored on the vertical boring machine. Care should be taken
that the finished bore is straight, concentric to the tread of the wheel and has a smooth surface
free from ridges, scores and chatter marks. A radius of 2.5 mm is provided on the hub to
facilitate mounting. It must be made after the finishing cut.

 INSPECTION OF RE-BORED WHEEL DISC

The rebored wheel disc should be inspected with the help of an inside micrometer to ensure
consistent results. Each wheel bore must be checked at not less than three points in its length
and on the different diameters at each of these points to ensure roundness and absence of
tapers. The variation for any of these measurements must not exceed 0.05 mm.

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 CHAPTER: 8 REPLACEMENT OFWHEELS
During pre-inspection, if it is found that tread diameters of the solid disc wheels cannot be
issued at the last shop issue, the wheel is taken for replacement of discs.

THE ACTIVITIES INVOLVED IN REPLACEMENT OF DISCS:

 Dismounting of Axle boxes & Roller Bearings Axle boxes are dropped from the RD Wheel. The
wheel is then taken for dismounting of roller bearings from journals.

 Inspection of Axle journals/ Ultrasonic testing of the axle Journal diameters should be
measured with an outside diameter to confirm to be within the permissible limits. The axle
should be ultrasonically tested for flaw detection and should be flawless.

 Pressing off rejected discs from a wheel The wheel is taken on the wheel press for separating
the rejected discs from the wheels.

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 CHAPTER: 9 BORING OF NEW WHEELS
New discs are bored on the vertical boring machine. Care should be taken to ensure the
finished bore is concentric to the tread of the wheel and has a smooth surface free from ridges,
scores and chatter marks. The radius of 2.5 mm, which is provided on the wheel bore to
facilitate mounting, should be made after the finishing cut. An inside micrometer should be
used for measuring wheel bores to ensure consistent results. Each wheel bore must be checked
at not less than three points in its length and on the different diameters at each of these points
to ensure roundness and absence of tapers. The variation among any of these measurements
must not exceed 0.05 mm. If any taper does exist, the small diameter must be at an outside end
of the hub bore (reverse taper is not allowed).

 MACHINING OF WHEEL SEATS ON AN OLD AXLE FOR MATCHING OF

WHEEL DISC BORES
The wheel seats on the old axle (released from RD wheels) are machined to suit the bore of the
wheel discs keeping interference allowance as prescribed. The bore and the wheel seat should
be machined to the specified surface finish to achieve correct interference fit and pressing in
pressure.

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CHAPTER: 10 PRESSING OF WHEEL ON AXLE
 Before pressing on operation, wheel seats on the axle and bore of the wheel should be
carefully cleaned to remove rust, grit, swarf, dirt etc.

 The wheel seat should be lubricated with a mixture of basic carbonate white lead and boiled
linseed oil, in the proportion of 1.2 kg. of white lead paste to 1 liter of boiled linseed oil. The
wheel and axle should be properly aligned on the wheel press.

 The wheel press should be equipped with a dial pressure gauge and pressure recording
gauge with graphs to record mounting pressure diagrams for each assembly.

 Wheels should be mounted within the prescribed pressure limits. Pressing pressure should
be 400 to 600 kg/mm of diameter of wheel seat. For ICF 16t axle with wheel seat diameter from
176mm to 178mm, the pressing pressure should be 71t to 108t.

 Wheels should be mounted (pressed in) carefully on the axle such that the wheel gauge
distance is maintained.

 The axle end should be stamped with the shop code, date of mounting, pressing in pressure,
axle no., cast no., cons. no. to enable identification of wheels.

 The wheel gauge should be checked by gauging at three or more equi-angular points around
the circumference.

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CHAPTER: 11 ULTRASONIC TESTING OF WHEEL AND AXLES
11.1 TECHNIQUES TO TEST AXLES
All incoming wheel sets are tested for flaw detection test of axles in the shop before sending
them to service. Following techniques are adopted to test the axles.
i.Far end scanning
ii. Trace delay
iii. Near end low angle scanning
iv. High angle scanning
I.FARENDSCANNINGTECHNIQUE:
This technique is used to detect fatigue crack, manufacturing defects, blow holes etc. In this
technique, normal probe of 1 MHz to 2.5 MHz having 10 mm. and 20 mm. in size are generally
used. By this technique, full length of the axle specimen is covered for test.
II. TRACE DELAY TECHNIQUE: In this technique, the specimen is tested part by part with normal
probe.
III. NEAR AND LOW ANGLE SCANNING: In this technique, the area which cannot be tested by far
end scanning i.e. raised portion or shadow zone (wheel seat) is tested by low angle. In this
technique, angular probe of 2.5 MHz having angle of 10”, 12.5”, 15”, & 17.5” are generally
used.
IV.HIGHANGLESCANNING: This technique is a confirmation test of low angle scanning. This test
is carried out on the body of the specimen. In this technique, high angular probe of 37, 60, & 70
are generally used.
11.2 CHOICE OF COUPLANT
The choice of couplant depends on the condition of probing surface. The following couplant
may be used for ultrasonic testing of axles.

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 CHAPTER: 12 STAMPING OF PARTICULARS
Whenever axles are renewed the workshop shall punch in 5 mm letters the following
particulars on the journal face
• Place of pressing
• Date of pressing
• Pressure of pressing

Fig 12.1 Stamping on Axle

Whenever UT is done the details shall be stamped cold on the inner hub fillet with 6 mm punch
not more than 1.5 mm depth

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 CHAPTER: 13 WHEEL DEFECTS
13.1 TYPES OF WHEEL DEFECTS
• Manufacturing Defects
• Improper Assembly Practices
• Normal Wear and Tear during service

MANUFACTURING DEFECTS
• Casting Defects
• Improper Heat treatment
• Machining Imperfections

IMPROPER ASSEMBLY PRACTICES

• Stipulated dimensional tolerances for Wheel seat and bore not adhered to resulting in use of higher
or lower than the prescribed force during pressing leading to improper wheel set assembly.
• Ovality on Journals - 0.02 mm (max)
• Taper on Journal - 0.01mm (max)
• Difference in dia of wheels on the same axle should not exceed 0.5 mm

MEASURABLE WHEEL DEFECTS ARISING DUE TO NORMAL WEAR & TEAR DURING SERVICE
• Thin flange
• Deep flange
• Sharp flange
• Less radius at root of flange
• Hollow tyre
• Thin tyre
• Flat tyre

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35
13.7 CHECKING THE ROOT OF FLANGE

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13.14 LOOSE AXLE

• While assembling wheel with axle proper interference should be maintained between wheel and axle.
Due to improper selection of interference the wheel may shift outwards or it may come out completely.
Loose axle is a rejectable defect.
• Axles involved in Accidents should be magnaflux tested in addition to Ultrasonic test.
• Axle having notch should be withdrawn from service
• All wheel sets withdrawn from service for any of the conditions mentioned above must be sent to the
associated workshops for detailed investigations and further disposal.
• The date and station code of the maintenance depot where the wheels are changed should be
stencilled on the end panels. An entry should also be made in the maintenance card of the coach.
• No repairs, except wheel profiling of wheel sets is permitted to be done in the maintenance depot.

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43
 CHAPTER: 14 BEARING SECTION
For carrying the load of the entire coach of double row self-aligning spherical
bearings are used for the ICF and LHB wheels. For BLCN and Diesel wheels CTRB
(Cartridge Tapered Roller Bearing) are used.

14.1 INSPECTION OF SPHERICAL BEARING

 All bearings should be cleaned, inspected and filled with fresh grease at every
POH.
 All bearings should be dismounted every alternate POH or 2 lakh km whichever
is earlier in the workshop for renewal of felt sealing ring and overhaul of the roller
bearings.

14.2 SPHERICAL BEARING MAINTENANCE IN SHOP

Spherical Bearing Maintenance Shop should be well equipped with all the tools,
equipment and facilities for careful bearing handling. It should have proper
workflow for easy maintenance of roller bearings. Clean surroundings and dust
free atmosphere should be maintained in the shop. It should have adequate
equipment and facilities for cleaning, handling, dismounting, dismounting,
inspection, repair and storage of roller bearings.

14.3 INSPECTION OF SPHERICAL BEARINGS IN MOUNTED POSITION

following procedure should be adopted for carrying out inspection of spherical
bearings in mounted position.
 Clean the exterior of axle box, front cover, axle box housing.
 Remove axle box with the help of mechanical screw type puller, by taking care
to protect axle centre with the use of pad not allowing the screw to rest on the
axle centre. The end locking plate should be removed.
 Examine the grease for consistency, colour, contamination with water, foreign
particles, etc.
 If the grease is in good condition, the bearing should not be dismounted,
provided its felt sealing ring and rear cover do not require renewal.
 Remove old greas, bearing and its components should be thoroughly washed
and cleaned with kerosene and then petrol/white spirit.

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45
46
 CHAPTER: 15 LUBRICATION

15.1 GUIDELINES FOR APPLICATION OF GREASE

 The quantity of grease filled per axle box
SKF make bearing 2.00 kg
Other make bearings 1.75 kg
 Only lithium base grease of approved brands should be used

15.2 GUIDELINES FOR STORAGE OF GREASE

1. Grease drums should be stored in vertical position in a covered
room.
2. Take all precautions to prevent contamination of grease due to dirt,
moisture, dust foreign particals etc.
3. Always store grease in container with cover.
4. Never mix different types of grease.
5. Use only clean tools and container when handling the grease.

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CHAPTER: 16 INSPECTION OF OTHER SPHERICAL
BEARING COMPONENTS
The following components other than roller bearing should be inspected during roller bearing
maintenance in the workshop.
 Axle end holes
 End locking plates
 End locking bolts
 Retaining Ring
 Rear and Front Cover
 Axle box housing

I) AXLE END HOLE

The axle end holes should be checked with GO–NO GO thread plug gauge for correct size and
thread condition. If any of the tapped hole is worn out, a helical thread insert could be fitted in
that hole for using the same size of bolt. The practice of blocking of worn out holes and drilling
a new hole 60o away from old ones reduces the probing are on axle face for ultrasonic testing.
II) END LOCKING PLATE
End locking plates should be replaced every time its folds are opened to unscrew bolt.
III) END LOCKING BOLT
 The end locking bolts should be of high tensile steel of reputed brand/ RDSO approved
manufacturers. The condition of their threads should be checked with GO-NO GO thread ring
gauges and worn out bolts replaced.
 The bolt head should be free from any damages and should have proper spanner grip. The
length of the bolt should be less than that of tapped axle end holes. Bolts in service should not
be reused unless they meet the above standards.
 Bolt while fitting should have no radial or axial play.
IV) RETAINING RING
The retaining ring should be cleaned and inspected for flatness and correct dimensions. The
mating surfaces must be free from burr, sharp edge, rust or any other type of defect that will
prevent proper seating with mating part.
V) COLLAR
The collar should not be dismounted unless it is damaged or the interference fit with the axle is
lost. Once dismounted, it should be invariably replaced.
VI) FELT RING
Whenever the rear cover is removed from the roller bearing axle box, the felt ring should be
replaced.

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VII) REAR AND FRONT COVER
These covers should be cleaned and inspected for any crack, correct dimensions and
concentricity of bolt holes. The height should be 61+/- 0.1 mm in the as cast condition and may
be checked with the help of a gauge. In case the cover is worn out, it should be replaced.
However the height of the shoulder from the face of both front cover and rear cover should be
60 0.1 mm (refer RDSO's letter no. MC/RB/General dtd. 24/27-3-2000).

VIII) AXLE BOX HOUSING

The axle boxes should be thoroughly cleaned in the axle box cleaning plant and inspected.
Check for any mechanical damage or distortion. The housing should be free from score marks,
excessive corrosion and any wear. The dimensions of the bore and width should be within
specified tolerance limits. The axle box should be checked for distortion, particularly at the
spring seat. Use cylindrical gauge fitted with dial indicator to check housing bore diameter at
bearing seat (see fig 8). Check the bore at several places and it must be within specified
tolerances. Housings not conforming to the limits or otherwise found unsatisfactory must be
rejected.

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 CHAPTER: 17 DISMOUNTING OF BEARING
For dismounting roller bearings, a special hydraulic dismounting equipment is used (see figure
17.1). Following is the procedure for dismounting of roller bearing - Oil is injected between the
journal and bore of the inner ring with high pressure, which expands inner ring resulting in
breaking of interference. The bearing becomes loose on the journal and slides over it. The
bearing is then removed from the journal and sent to the cleaning plant. Bearing after cleaning
is thoroughly inspected for defects.

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