Standard Tightening Torque For Bolts And Nuts - Komatsu PW98MR-10 Operation & Maintenance Manual

STANDARD TIGHTENING TORQUE FOR BOLTS AND NUTS

STANDARD TIGHTENING TORQUE FOR BOLTS AND
NUTS
Tightening torque list
If nuts, bolts, or other parts are not tightened to the specified torque, it will cause looseness or damage
to the tightened parts, and this will cause failure of the machine or problems with operation. Always be
careful when tightening parts.
Unless otherwise specified, tighten the metric nuts and bolts to
the torque shown in the table below.
If it is necessary to replace any nut or bolt, Komatsu recom-
mends using Komatsu genuine part of the same size as the
part that is removed.
Thread
Width
diame-
across
ter of
flats "b"
bolt "a"
(mm)
Nm
(mm)
6 10 13.3
8 13
10 17
12 19 111
14 22 172
16 24 260
18 27 360
20 30 510
22 32 688
24 36 883
27 41 1295
30 46 1715
33 50 2205
36 55 2745
39 60 3260
4-8
k k
Target value
kgm lbft
1.35 9.8
31 3.2 22.8
67 6.8 48.8
11.3 81.4
17.5 127
26.5 192
37 268
52.3 378
70.3 508
90 651
133 957
175 1265
225 1630
280 2025
333 2405
CAUTION
Tightening torque
Nm
11.8 to 14.7
27 to 34
59 to 74
98 to 123
153 to 190
235 to 285
320 to 400
455 to 565
610 to 765
785 to 980
1150 to 1440
1520 to 1910
1960 to 2450
2450 to 3040
2890 to 3630
WENAM00061
MAINTENANCE
Allowable range
kgm
1.2 to 1.5 8.7 to 10.8
2.8 to 3.5 20.3 to 25.3
6 to 7.5 43.4 to 54.2
10 to 12.5 72.3 to 90.4
15.5 to 19.5 112 to 141
23.5 to 29.5 170 to 213
33 to 41 239 to 297
46.5 to 58 336 to 420
62.5 to 78 452 to 564
80 to 100 579 to 753
118 to 147 853 to 1060
155 to 195 1120 to 1410
200 to 250 1450 to 1810
250 to 310 1810 to 2240
295 to 370 2130 to 2680
lbft