4.5 Standard tightening torques for bolts and nuts Maintenance Torque list 4.5 Standard tightening torques for bolts and nuts 4.5.1 Torque list If nuts, bolts, or other parts are not tightened to the speci- fied torque, it will cause looseness or damage to the tight- ened 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.
GK032236 WA150-5H – VEAM934100 4-17 CAUTION CAUTION Thread diameter of bolt (a)(mm) Width across flats (b)(mm) Tightening torque Target value Service limit N·m kgf·m lbft N·m kgf·m lbft 6 8 10 12 14 10 13 17 19 22 13.2 31 66 113 172 1.35 3.2 6.7 11.5 17.5 9.8 23.1 48.5 83.2 126.6 11.8-14.7 1.2-1.5 27-34 2.8-3.5 59-74 6.0-7.5 98-123 10.0-12 153-190 15.5-19 8.7-10.8 20.3-25.3 43.4-54.2 .5 72.3-90.4 .5 112.1-141 16 18 20 22 24 24 27 30 32 36 260 360 510 688 883 26.5 37 52.3 70.3 90 191.7 267.6 378.3 508.5 651 235-285 23.5-29 320-400 33.0-41 455-565 46.5-58 610-765 62.5-78 785-980 80.0-100 .5 170.0-213.4 .0 238.7-296.6 .0 336.3-419.5 .0 452.1-564.2 .0 578.6-723.3 27 30 33 36 39 41 46 50 55 60 1295 1720 2210 2750 3280 132.5 175.0 225.0 280.0 335.0 958.4 1265.8 1627.4 2025.2 2423.1 1150-1440 118.0-14 1520-1910 155.0-19 1960-2450 200.0-25 2450-3040 250.0-31 2890-3630 295.0-37 7.0 853.5-1063.3 5.0 1121.1-1410.4 0.0 1446.6-1808.3 0.0 1808.3-2242.2 0.0 2133.7-2676.2