BOGIES AND SUSPENSION - South Central Railway

CHAPTER 6 – BOGIES AND SUSPENSION
WAGON MAINTENANCE MANUAL
Page 86 of 121
The ovalty and taper on the journal should be within the permissible limit of
0.1 mm. The ovalty and taper of the journal should be checked by measuring the
diameter with micrometer at 3 locations both on the vertical and horizontal axis. If
required, measurements at more locations should also be taken. If cases of ovalty and
taper going beyond the permissible limits, are detected, the grinding and burnishing
machine should be checked and its defects should be rectified. Cent percent check for
ovality and taper should be carried out. Diameter of all journals coming one of the
wheel shop should be measured & a record be maintained. The dia of the journal
should be written with chalk on inner surface of the wheel for guidance of the staff in
the lifting section. The top surface of the outer collar, where necessary, must be
finished by a suitable form tool either on grinding or burnishing machines or on
another suitable lathe.
As indicated above, normally the minimum length of the journal for a
particular step size diameter is automatically re-ensured. However, there may be
exception and the minimum length of the journal should, therefore, be checked by
means of a gauge.
Wheels which are required to be send to out stations after repair or which are
required to be kept in spare pool, for some days, should be carefully painted with 3
coats of bituminous solution to IS : Specification No. 158. To protect the journal
surface of the wheels being sent to out stations against mechanical damage, it should
be fitted with tightly bound wood lagging extending outside the collar and up to
wheel seat, completely surrounding the journal.
Concentricity of the journal and wheel tread is an important matter for
satisfactory performance of the bearings and this should be occasionally checked
when wheels are attended to in shop or in sick lines.
The total permissible wear in the length of the different size of BG and MG
journals of goods stock for shop purposes, will be as under :-
Size of Journals
Maximum permissible wear on
Length of Inner Outer
Journal Collar Collar
(mm) (mm) (mm)
(mm)
BG
(i) 255x127 }
(ii) 254x127 }
(iii) 229x144 }
MG
(iv) 230x115 }
(v) 229x114 }
11 6 5 11
(vi) 180x100 10.5 6 4.5 8
(vii) 170x102 11 6 5 8
(vii) 178x89 8 5 3 8
Maximum
thickness
of
outer collar