Standard Tightening Torques For Bolts And Nuts; Torque List - Komatsu ecot3 HD465-7E0 Operation & Maintenance Manual

MAINTENANCE

STANDARD TIGHTENING TORQUES FOR BOLTS AND NUTS

TORQUE LIST

When tightening torques are not entered at concerned parts, tighten the metric nuts and bolts to the torque shown
in the table below.
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.
Please order nuts and bolts from your Komatsu distributor.
Thread Width
diameter across
Target value
of bolt flats
Nm kgm
(a)(mm) (b)(mm)
6 10 13.2 1.35
8 13 31 3.2
10 17 66 6.7
12 19 113 11.5
14 22 177
16 24 279 28.5
18 27 382
20 30 549
22 32 745
24 36 927 94.5
27 41 1320 135.0
30 46 1720 175.0
33 50 2210 225.0
36 55 2750 280.0
39 60 3280 335.0
If parts made from plastic, such as panels, are tightened to an excessive torque, the tightened portion may break.
Always keep to the standard tightening torque for nuts and bolts.
Apply the following table for Hydraulic Hose.
Face seal
Width
Nominal -
across
No. of Target value
flats (b)
threads (a)
Nm kgm
(mm)
9/16 -18UNF 19 44
11/16 -16UN 22 74
13/16 -16UN 27 103 10.5 75.9 84 to 132 8.5 to 13.5
1 -14UNS 32 157 16.0 115.7 128 to 186 13.0 to 19.0 94.0 to 137.4
13/16 -12UN 36 216 22.0 159.1 177 to 245 18.0 to 25.0 130.2 to 180.8
Tightening torque
Service limit
lbft Nm kgm
9.8 11.8-14.7 1.2-1.5
23.1 27-34 2.8-3.5
48.5 59-74 6.0-7.5
83.2 98-123 10.0-12.5
18 130.2 157-196 16.0-20.0
206.1 245-309 25.0-31.5
39 282.1 343-425 35.0-43.5
56 405.0 490-608 50.0-62.0
76 549.7 662-829 67.5-84.5
683.5 824-1030 84.0-105.0
976.5 1180-1470 120.0-150.0
1265.8 1520-1910 155.0-195.0
1627.4 1960-2450 200.0-250.0
2025.2 2450-3040 250.0-310.0
2423.1 2890-3630 295.0-370.0
Tightening torque
Permissible range
lbft Nm kgm
4.5 32.5 35 to 63 3.5 to 6.5
7.5 54.2 54 to 93 5.5 to 9.5
STANDARD TIGHTENING TORQUES FOR BOLTS AND NUTS
lbft
8.7-10.8
20.3-25.3
43.4-54.2
72.3-90.4
115.7-144.7
180.8-227.8
253.2-314.6
361.7-448.4
488.2-611.2
607.6-759.5
868.0-1085.0
1121.1-1410.4
1446.6-1808.3
1808.3-2242.2
2133.7-2676.2
lbft
25.3 to 39.8
39.8 to 68.7
61.5 to 97.6
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