BOGIES AND SUSPENSION - South Central Railway

CHAPTER 6 – BOGIES AND SUSPENSION
WAGON MAINTENANCE MANUAL
Page 94 of 121
v. Examine the brass for damage, such as cracks. Tap the brass to check the
white metal bond by holding it in a suspension link. If the bond is satisfactory
but the white metal has only slightly spread to the sides or ends, it should be
dressed up for reuse. It must also be suitably relieved at the sides so as to
restore an arc of contract of about 30 o on the crown. When put back in
position, there should also be a minimum lateral play of 5 mm for B.G. and 3
mm for M.G.
vi. However, the old brass is unfit for reuse, it should be replaced by new brass
already side relieved. For this purpose, the lifting staff should carry at the
commencement of their duty, a few suitably side relieved step size brasses in a
wooden box.
vii. The key plate must then be inspected to check that it is not battered at the front
end and that it sits square on the back of the old serviceable brass or the new
brass, as the case may be. This to be checked by putting hand-pressure at the
diagonal ends to see that there is no rocking motion. When necessary, the
key-plate or the back of the brass should be suitably filed. A bad fitting key
plate or one with badly battered end must be replaced by a new one.
viii. It is also necessary to inspect the dust shield is missing or very badly worn, in
which case it has to be replaced. In such cases the top cover plate, if found
deficient must also be made good.
ix. Before re-fitting a bearing, the journal as also the bearing surface of the brass
must be smeared with clean medium axle oil. Similarly, the key plate should
also be oiled on both sides. After fitting the key plate it should be checked
that it is in correct position and its front end is behind the key plate retaining
lug.
x. The lifting back should then be lowered taking care that the position of the key
plate and the brass is correctly set under load and that the brass does not bind
against the journal cap.
xi. New packing should be carried in buckets or small drums fitted with lids,
painted green on the outside. Clean and soaked wooden packing should also
be carried in the same container.
xii. The back roll should first be inserted in the axle box by placing it across the
journal. It should be pressed with a re-packing shovel to the extreme back
end. The roll must be placed in the centre and its ends lifted equally. The two
centre rolls should then be placed one behind the other and pressed against the
back roll. The second centre roll, when in position, should not extend
outward, beyond the inside edge of the outer - collar of the journal. It should
also be seen that the ends of the centre rolls are at the same height.
xiii. 170 ml oil for BG and 115 ml for MG should now be syringed uniformly
over the different rolls before inserting the front roll. If syringe is not done
uniformly, most of the oil falls in front portion and there will be a tendency for
this oil to spill out. Further, even when it is syringe uniformly, at least 5
minutes time should be allowed for the oil to soak & settle down as otherwise,
when the front roll is fixed and pressed, the oil will ooze out. Thereafter place
the wooden keep & press it down on the front roll, and push it into position so
that when released, it is firmly held in position without any clearance at the
top.