Komatsu PC30MR-5, Operation & Maintenance Manual

Page: 265 / 380

STANDARD TIGHTENING TORQUE FOR BOLTS AND
NUTS
Tightening torque list
k k
CAUTION
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 di-
ameter of
bolt “a”
(mm)
Width
across
flats “b”
(mm)
Tightening torque
Target value Allowable range
Nm kgm Nm kgm
6 10 13.3 1.35 11.8 to 14.7 1.2 to 1.5
8 13 31 3.2 27 to 34 2.8 to 3.5
10 17 67 6.8 59 to 74 6.0 to 7.5
12 19 111 11.3 98 to 123 10.0 to 12.5
14 22 172 17.5 153 to 190 15.5 to 19.5
16 24 260 26.5 235 to 285 23.5 to 29.5
18 27 360 37.0 320 to 400 33 to 41
20 30 510 52.3 455 to 565 46.5 to 58
22 32 688 70.3 610 to 765 62.5 to 78
24 36 883 90. 785 to 980 80 to 100
27 41 1295 133 1150 to 1440 118 to 147
30 46 1715 175 1520 to 1910 155 to 195
33 50 2205 225 1960 to 2450 200 to 250
36 55 2745 280 2450 to 3040 250 to 310
39 60 3260 333 2890 to 3630 295 to 370
Tighten the hoses to the torque shown in the table.
MAINTENANCE STANDARD TIGHTENING TORQUE FOR BOLTS AND NUTS
4-9
WENAM00150