Standard Tightening Torque For Bolts And Nuts - Komatsu WA480-8 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 di-
Width
ameter of
across flats
bolt "a"
"b" (mm)
(mm)
6 10
8 13
10 17
12 19
14 22
16 24
18 27
20 30
22 32
24 36
27 41
30 46
33 50
36 55
39 60
Tighten the hoses by the following torque shown in the table.
4-10
k k
CAUTION
Target value
Nm kgm
13.3 1.35
31 3.2
67 6.8
111 11.3
172 17.5
260 26.5
360 37
510 52.3
688 70.3
883 90
1295 133
1715 175
2205 225
2745 280
3260 333
Tightening torque
Allowable range
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
MAINTENANCE
kgm
1.2 to 1.5
2.8 to 3.5
6.0 to 7.5
10.0 to 12.5
15.5 to 19.5
23.5 to 29.5
33 to 41
46.5 to 58
62.5 to 78
80 to 100
118 to 147
155 to 195
200 to 250
250 to 310
295 to 370