Table 1 Tightening torque for bolts not specified in text Unit: Nm {kgm} a For symbols “a” and “b” in the table, see Fig. 1.
18 Nominal size of thread × pitch a (mm) Width across flats (= Socket size) b (mm) Tightening torque Target Range M6 × 1 10 12 {1.2} 8.8 – 14.7 {0.9 – 1.5} M8 × 1.25 13 25 {2.5} 14.7 – 34 {1.5 – 3.5} M10 × 1.5 17 54 {5.5} 34 – 74 {3.5 – 7.5} M12 × 1.75 19 89 {9} 54 – 123 {5.5 – 12.5} M14 × 2 22 137 {14} 84 – 196 {8.5 – 20} M16 × 2 24 230 {23.5} 147 – 309 {15 – 31.5} M18 × 2.5 27 315 {32} 201 – 427 {20.5 – 43.5} M20 × 2.5 30 460 {47} 319 – 608 {32.5 – 62} M22 × 2.5 32 650 {66.5} 471 – 829 {48 – 84.5} M24 × 3 36 810 {82.5} 588 – 1030 {60 – 105} M27 × 3 41 1180 {120} 883 – 1470 {90 – 150} M30 × 3 46 1520 {155} 1130 – 1910 {115 – 195} M33 × 3 50 1960 {200} 1470 – 2450 {150 – 250} M36 × 3 55 2450 {250} 1860 – 3040 {190 – 310} M39 × 3 60 2940 {300} 2260 – 3630 {230 – 370}