Komatsu 930E-2, Руководство по ремонту

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“TURN-OF-THE-NUT” Tightening Procedure
a. Tighten all fourteen capscrews (1, 6, 8, Figure
2-3) to 400
±±±±
40 ft .lbs. (542
±±±±
5 N.m) torque.
Use a torque wrench of known calibration.
b. Maintain this torque on the top two corner
capscrews and the bottom outer four cap-
screws (item 8, the 4 bottom capscrews with
nuts).
c. Loosen the 8 remaining capscrews and then
tighten again using “turn-of-the-nut” tightening
procedure as follows:
d. For the four, 6.0 in. (15 cm) long capscrews (1,
Figure 2-3) at the upper mount, tighten cap-
screws initially to 70 ft. lbs. (95 N.m) torque;
then advance capscrew head 60° using steps
d-1.) through d-3.). Refer to Figure 2-5.
For the four inner, 14.0 in. (36 cm) long cap-
screws (6, Figure 2-3), tighten capscrews in-
itially to 100 ft. lbs. (136 N.m) torque; then
advance capscrew head 120° using steps d-1)
through d-3). Refer to Figure 2-6.
1.) Mark a reference line on a corner of the
hexagonal capscrew head or nut and the
mounting surface opposite this corner as
shown. Then mark the position located 60°
or 120° clockwise relative to the first refer-
ence line on the mounting surface. Refer to
Figures 2-5 and 2-6.
2.) To insure that the opposite end of the turning
member, either the capscrew head or nut
remains stationary, scribe a reference mark
for this check.
3.) Each corner of a hexagon represents 60°.
The turning member, either the capscrew
head or nut, is turned until the marked corner
is adjacent with the marked reference line.
Check to make sure that the opposite end of
the turning member has NOT turned during
the tightening procedure. NOTE: Do not ex-
ceed 4 RPM tightening speed. Do not ham-
mer or jerk wrench during the tightening
procedure.
e. Loosen the top two corner capscrews (1) and
the bottom outer four capscrews (8, the 4 bot-
tom capscrews with nuts).
1.) Tighten the top, two corner 6.0 in. (15 cm)
capscrews to 70 ft. lbs. (95 N.m) torque,
then use “turn-of-the-nut” method to ad-
vance capscrew heads 60°.
2.) Tighten the bottom, outer four 14.0 in. (36
cm) capscrews to 200 ft. lbs. (271 N.m)
torque, then use “turn-of-the-nut” method to
advance capscrew heads 120°.
NOTE: If for any reason, these fasteners need to be
checked for tightness after completing the above pro-
cedure; loosen and inspect all 14 capscrews and
repeat entire process, starting with cleaning and lubri-
cating capscrews, washers, and nuts. In addition, the
capscrew head will need to be appropriately marked
to show an additional use.
7. Charge suspension with dry nitrogen to fully ex-
tend suspension piston before installing front
wheel hub and spindle.
8. Install wheel, spindle, and tire according to in-
structions in Section “G”.
9. Service the suspension. For instructions refer to
HYDRAIR
®
II “Oiling and Charging Procedure”.
10. Install suspension boot and secure with clamp.
FIGURE 2-5. REFERENCE MARKS FOR 60
DEGREE ADVANCE
(6.0 in. (15 cm) Capscrews)
FIGURE 2-6. REFERENCE MARKS FOR 120
DEGREE ADVANCE
(14.0 in. (36 cm) Capscrews)
H2-4 Front Suspensions H02013 2/01