Tightening Torque Specifications; Tightening Torque List - Komatsu ecot3 Operation And Maintenance Manual

MAINTENANCE

TIGHTENING TORQUE SPECIFICATIONS

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 pay careful attention 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, always use a Komatsu genuine part of the same size as the part that was
replaced.
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 22 172 17.5
16 24 260 26.5
18 27 360 37
20 30 510 52.3
22 32 688 70.3
24 36 883 90
27 41 1295 132.5
30 46 1720 175.0 1265.8
33 50 2210 225.0 1627.4
36 55 2750 280.0 2025.2
39 60 3280 335.0 2423.1
Apply the following table for Hydraulic Hose.
Hose Width
nomi across
nal flat
Target valve
num a
Nm kgm lbft
ber (mm)
02 19 44 4.5 32.5
22 74 7.5 54.2
03
24 78 8.0 57.9
04 27 103 10.5 75.9 84 to 132 8.5 to 13.5
05 32 157 16.0 115.7 128 to 186 13.0 to 19.0 94.0 to 137.4
06 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 to 14.7 1.2 to 1.5
23.1 27 to 34 2.8 to 3.5
48.5 59 to 74 6.0 to 7.5
83.2 98 to 123 10.0 to 12.5
126.6 153 to 190 15.5 to 19.5
191.7 235 to 285 23.5 to 29.5
267.6 320 to 400 33.0 to 41.0
378.3 455 to 565 46.5 to 58.0
508.5 610 to 765 62.5 to 78.0
651 785 to 980 80.0 to 100.0
958.4 1150 to 1440 118.0 to 147.0
1520 to 1910 155.0 to 195.0
1960 to 2450 200.0 to 250.0
2450 to 3040 250.0 to 310.0
2890 to 3630 295.0 to 370.0
Tightening torque
Service limit
Nm kgm
35 to 54 3.5 to 5.5
54 to 93 5.5 to 9.5
59 to 98 6.0 to 10.0
CAUTION
lbft
8.7 to 10.8
20.3 to 25.3
43.4 to 54.2
72.3 to 90.4
112.1 to 141
170.0 to 213.4
238.7 to 296.6
336.3 to 419.5
452.1 to 564.2
578.6 to 723.3
853.5 to 1063.3
1121.1 to 1410.4
1446.6 to 1808.3
1808.3 to 2242.2
2133.7 to 2676.2
lbft
25.3 to 47.0
39.8 to 68.7
43.4 to 72.3
61.5 to 97.6
TIGHTENING TORQUE SPECIFICATIONS
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