Group 34, Uprights
34-4-6 •
Carriage and Upright Roller Clearance Checks and Shim Adjustments
SM 765, Nov ’06
6. Move the clamp to the shimmed side and clamp the
rollers against the shim and the rail web by position-
ing the clamp between the top and middle carriage
rollers.
7. Cam the thrust roller on the shimmed side against the
rail clockwise and tighten the cap screws firmly.
N
TE
Make sure the roller does not rotate with the
cap screw when tightening.
8. Insert a 0.5 mm (0.02 in) shim in the opposite roller.
If a 0.5 mm (0.02 in) shim will not fit, insert a 0.25
mm (0.01 in) shim.
9. Loosen the clamp and remove the shim.
10. Reposition the clamp on the opposite side and draw
the roller against the shim and rail web.
11. Cam the thrust roller on this shimmed side toward the
rail clockwise and tighten the cap screws firmly.
N
TE
Make sure the roller does not rotate with the
cap screw when tightening.
12. Loosen the clamp and remove the shim.
13. Use a crow’s foot to torque the cap screws 70-80 N⋅m
(51.5-59.2 ft-lb).
N
TE
If a crow’s foot is not available, the carriage
can be raised to the top of the inner rail and a
socket used to tighten to the correct torque.
14. Position the carriage to access the jam nut on the
back side of the cap screw and torque to 70-80 N⋅m
(51.5-59.2 ft-lb).
Oversize Rollers
At the time of roller shimming,
you may want to replace the lift
rollers with oversize rollers to
counter rail flange wear as
detected by inspection and the
load test. Because there is only
one size of oversize rollers, you
can install them only if they were
not installed previously.
Identify oversize rollers as fol-
lows: If a roller is oversize, it has
an indented radius in the outer
edge of its mounting side, as shown below.
Lift Roller Shimming
You need to shim lift rollers if the roller side clearance
checks indicated that clearance was excessive at either the
narrowest or widest span of the roller set’s adjacent rail
set.
Your objective in shimming is to add only enough shims
to bring the clearances at both the widest and narrowest
spans into tolerances. In practice, you achieve this by
shimming to obtain the smallest possible clearance at the
narrowest span of the rail set.
Carriage Roller Shimming
Using the measurement you recorded in previously in the
“Roller Side Clearance Checks,” determine the number of
shims required to reduce the carriage roller clearance at
the narrowest span on the inner rail to 0-0.75 mm (0-0.03
in):
1. Remove the carriage as described in Section 8, “Fork
and Carriage Removal and Replacement.”
2. Remove the rollers (note the number of shims
already on the roller shafts, if any).
• Clean and inspect roller bearings, shims, and
shafts.
To Next Page
Loading...
