MAINTENANCE TIGHTENING TORQUE SPECIFICATIONS TIGHTENING TORQUE SPECIFICATIONS 0. TIGHTENING TORQUE LIST 0. 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. The tightening torque is determined by the width across the flats 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.
Use the following table for Hydraulic Hose.
4-11 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 66 113 177 1.35 3.2 6.7 11.5 18 9.8 23.1 48.5 83.2 130.2 11.8-14.7 27-34 59-74 98-123 157-196 1.2-1.5 2.8-3.5 6.0-7.5 10.0-12.5 16.0-20.0 8.7-10.8 20.3-25.3 43.4-54.2 72.3-90.4 115.7-144.7 16 18 20 22 24 24 27 30 32 36 279 382 549 745 927 28.5 39 56 76 94.5 206.1 282.1 405.0 549.7 683.5 245-309 343-425 490-608 662-829 824-1030 25.0-31.5 35.0-43.5 50.0-62.0 67.5-84.5 84.0-105.0 180.8-227.8 253.2-314.6 361.7-448.4 488.2-611.2 607.6-759.5 27 30 33 36 39 41 46 50 55 60 1320 1720 2210 2750 3280 135.0 175.0 225.0 280.0 335.0 976.5 1265.8 1627.4 2025.2 2423.1 1180-1470 1520-1910 1960-2450 2450-3040 2890-3630 120.0-150.0 155.0-195.0 200.0-25.0 250.0-310.0 295.0-370.0 868.0-1085.0 1121.1-1410.4 1446.6-1808.3 1808.3-2242.2 2133.7-2676.2 Hose nominal number Width across flat (b)(mm) Tightening torque Target value Service limit N·m kgf·m lbft N·m kgf·m lbft 02 19 44 4.5 32.5 35 - 63 3.5 - 6.5 25.3 - 47.0 03 22 74 7.5 54.2 54 - 93 5.5 - 9.5 39.8 - 68.7 24 78 8.0 57.9 59 - 98 6.0 - 10.0 43.4 - 72.3 04 27 103 10.5 75.9 84 - 132 8.5 - 13.5 61.5 - 97.6 05 32 157 16.0 115.7 128 - 186 13.0 - 19.0 94.0 - 137.4 06 36 216 22.0 159.1 177 - 245 18.0 - 25.0 130.2 - 180.8