MLS MMLS3, Operator'S Manual

Page: 23 / 48

MLS Test Systems Pty Ltd
Revised: April 2013
21
SECTION 4: MAINTENANCE
Also read the maintenance recommendations in Appendix C
4.1 The yellow (polyurethane) guide wheels
The two wheels in the centre of each bogie (in line with the
shaft of the rubber wheel) carries nearly all the load. Inspect
them from time to time for signs of deterioration. The guide
wheels is expected to last about 10 Million axle loads, at which
time cracks may appear in the polyurethane. Wheels showing
signs of deterioration may be exchanged into positions where
the load is smaller. It is also OK to keep on using the wheels
with some small cracks in it. Never install an old and a new
wheel on the same shaft. The diameter of the two wheels
should not differ by more than 0.5mm
The sides of the guide wheels rub against the Vesconite guide
rails to steer the bogies and link sections. Although Vesconite
is a good bearing material the wheels may wear under dusty or
dirty conditions. New wheels are 33mm wide. Measure the
width and replace the wheels when the width is less than 30mm,
or exchange it to a position that shows less wear.
To reduce wear a very small amount of grease is applied to the
outside sidewalls of the yellow guide wheels. It is very
important not to use too much grease, which may spread to the
running surface of the wheels and the drive drum. This will
reduce the friction and make it impossible for the drum to drive
the wheels. A good guideline is not to use more than a total of
about 2 ml. for the 48 wheels. Repeat the application after
every 500 000 wheel loads or after some hot, wet tests have
been done.
To remove a guide wheel, remove the cap screw and washer,
replace the cap screw, without the washer, to protect the screw
tread in the centre of the shaft and pull the wheel out with the
supplied puller.