2. CONTENT:-
Introduction
Components of Wheel Set
Wheel Set Details
Wheel Maintenance Procedure In
Workshop
Wheel Profile
Wheel Machining
Cause Of Wheel Skidding
3. INTRODUCTION:-
• The movement of rolling stock on the track is possible only with
the help of wheels. For the gripping of wheels on turn, wheels
have a special type of profile are used. When train it is needed
that outer wheel moves more distance than inner wheel. Instead
of differential system for this purpose the wheel profile is made
tapered.
• The machine shop deals with different types of machine which are
used for components or part preparation, repairing of the parts
and production works.
4. COMPONENTS OF WHEEL SET :-
Wheel sets is an assembly of
components:-
• Wheel disk (solid) on both sides of
the axle.
• An axle to hold these wheel disks in
position.
• Axle boxes with roller bearing.
5. WHEEL SET DETAILS :-
Sr No. Details ICF (size in
mm)
LHB (size in
mm)
1. Diameter for New wheel 915+3/-0
915+4/-0
2. Axle length 2316+0.5/-0.0
2440+0.5/-0.0
3. Journal Daimeter 130.043 130.043
4. Diameter of old wheel 837 857
5. Distance b/w two flange 1600+1/-0
1600+1/-0
6. Thickness of flange 29.4 29.4
7. Thickness of disk 130+2/-2
130+2/-2
8. Axle wheel set (16 ton) 175-178 192-195
9. Axle wheel set (13 ton) 169-172 NA
10. Axle sholder Daimeter 145 160
6. WHEEL MAINTENANCE PROCEDURE IN WORKSHOP:-
During pre-inspection of incoming wheels, the wheel set is
inspected for assessing the condition of the components.
Measurement are carried out on the wheels received in shop
for repairs. Following measurements are carried.
• Measurements of a Wheel Gauge (Distance between Two wheels
flanges on the same Axle): -
Distance between two wheel flanges on the same axle should be
160+2/-1 mm. This measurement should be taken at three location
apart with the help of an adjustable pi-gauge. If wheel gauge is not in
permissible limits then the wheel discs have to be pressed off and then
pressed on.
7. • Measurements of a Wheel diameter (tread diameter)/Wheel Flanges:-
The wheel diameter is measure with the help of a trammel gauge. The
difference in tread diameter of the two wheel on the same axle should not
exceed 0.5mm. The variation on diameter under the same coach should
not exceed 13mm. The profile is to be turned 1mm above the
condemning unit.
• Inspection of Wheel disc:-
The wheel should be inspected for reject able defects in accordance with
RDSOs Instruction.
• Inspection of Wheel Flange:-
The flange 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
measurements of flange height and thickness are not possible with the
profile gauge. It is not possible with the profile gauge. It is recommended
to use a wheel sets is nominated for necessary repairs. After recording the
10. WHEEL MACHINING:-
In this section, wheels sets are removed from the bogie, the entire wheel
assembly is first inspected for assessing the condition of the components
of the wheel. The Wheel shop consists of following machine: -
1. Wheel Press CNC/non-CNC machine.
2. Vertical turning lathe.
3. Axle turning lathe CNC/non-CNC.
4. Wheel turning lathe.
5. Boring CNC/non-CNC machine.
6. CNC surface Wheel machine.
7. Capstan lathe machine.
8. Journal surface Grinding.
9. Wheel balancing machine
13. CAUSE OF WHEEL SKIDDING:-
• On excessive brake cylinder pressure (more than 2.5 kg/cm2).
• When at the time of application of dynamic braking. The brakes of loco would
have already been applied (In case of failure of D-1 pilot valve).
• Using dynamic braking at high speeds.
• Due to shunting of coaches with loco without connecting their B.P./vacuum
pipe.
• Continue working, when C-3-W distributor valve P/G handle is in wrong
position.
• Shunting at higher speeds.
• When any of the axles gets locked during on the line.
• Continue working when any of the brake cylinder of loco has gotten jammed.
• The time of application release of brakes of any of the brake cylinder being
larger than others.