Komatsu WA20-2, Operation & Maintenance Manual

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21. STANDARD TIGHTENING TORQUES FOR BOLTS AND NUTS
21.2 TORQUE LIST
Unless otherwise specified, tighten the metric bolts and nuts to
the torque shown in the table.
The tightening torque is determined by the width across the flats
b of the nut and bolt.
If it is necessary to replace any nut or bolt, always use a Komatsu
genuine part of the same size as the part that was replaced.
Nm (newton meter): 1Nm 0.1 kgm
0.74 lbft
Thread diameter Width across
of bolt (mm) flat (mm)
(a) (b)
Nm kgm lbft
6 10 13.2 ± 1.4 1.35 ± 0.15 9.73 ± 1.03
8 13 31.4 ± 2.9 3.2 ± 0.3 23.2 ± 2.1
10 17 65.7 ± 6.8 6.7 ± 0.7 48.5 ± 5.0
12 19 112 ± 9.8 11.5 ± 1.0 82.6 ± 7.2
14 22 177 ± 19 18.0 ± 2.0 131 ± 14
16 24 279 ± 29 28.5 ± 3 206 ± 21
18 27 383 ± 39 39 ± 3 282 ± 29
20 30 549 ± 58 56 ± 6 405 ± 43
22 32 745 ± 78 76 ± 8 549 ± 58
24 36 927 ± 98 94.5 ± 10 684 ± 72
27 41 1320 ± 140 135 ± 15 973 ± 100
30 46 1720 ± 190 175 ± 20 1270 ± 140
33 50 2210 ± 240 225 ± 25 1630 ± 180
36 55 2750 ± 290 280 ± 30 2030 ± 210
39 60 3280 ± 340 335 ± 35 2420 ± 250
=
=
NOTICE
When tightening panels or other parts having tightening fix-
tures made of plastic, be careful not to use excessive tightening
torque: doing so will damage the plastic parts.
AD054300
b
a
AD053380