JLG X20JP - X600AJ Service Manual - Manual (Page 51)

SECTION 3 - CHASSIS & TURNTABLE
3121623 – JLG Lift – 3-27
1) F
M
for hydraulic bolt-tensioning cylinder pretension ed
to 85% of yield strength.
Table 3-7.
1) F
M
for hydraulic bolt-tensioning cylinder pretensioned
to 85% of yield strength.
DETERMINING THE TILTING CLEARANCE
Tilting clearance increases as raceway system wear
increases. To determine the increase in tilting clearance a
basic measurement must be executed in installed status
and prior to first-time operation. This is the only way to
determine changes.
Figure 3-34. Determine tilting clearance
1. Upper mounting structure
2. Tilting direction
3. Main load-carrying zone
4. Lower mounting structure
Figure 3-35. Measurement setup
5. Dial gauge
6. Upper mounting structure
7. Slew Drive
8. Lower mounting structure
Procedure:
Tilting clearance measurement
9. Switch off the system and safeguard it from being
turned on again.
10. Permanently mark the measuring point in the main
load direction on the housing and on the bearing
ring.
11. Attach the dial gauge as shown in Fig. 24.
12. Apply defined tilt torque, at least 50% of max. oper-
ating load, in direction "A".
13. Set dial gauge to zero.
14. Apply defined tilt torque, at least 50% of max. oper-
ating load, in direction "B". The displayed measured
value m1 corresponds to the existing tilting clear-
ance and serves as the base value that will be used
for comparison in later inspections.
15. Log and document all measured values.
• All inspections at a later point in time must be executed
on the same measuring point, with the same loads, at
the same relative position of the bearing rings, and in
the same sequence.
• At pure axial or radial load check the tilting clearance
by applying an additional tilting load.
Mounting
bolt dimen-
sions
Mounting pretension force
F
M
1)
Strength class 10.9 in
kN lbs
1 – 8 UNC 301 67668
1 1/8 – 7 UNC 379 85203
1 1/4 – 7 UNC 481 108133
1 3/8 – 6 UNC 573 128816
1 1/2 – 6 UNC 697 156692
1 5/8 – 6 UNC 832 187041
1 3/4 – 5 UNC 942 211770