Tightening order
The bolt should be torqued in at least two steps using a torque wrench or a hydraulic tensioner.
The bolts should be tightened in the order shown in the diagram below.
Note: Tightening torque values correspond to a coefficient of friction (screw-nut/bolt) of 0.14 for threads with grease.
The preload Fm corresponds to 70% of the elastic limit (wrench) and 90% (hydraulic tensioner).
The following table shows:
Tightening torque in Nm (torque-limited wrench tightening)
Corresponding preload values Fm
Preload values obtained when using a hydraulic tensioner.
| Diameter | ifu | tightening torque | FM | tightening torque | FM | tightening torque | FM | FM | FM |
|---|---|---|---|---|---|---|---|---|---|
| (mm) | (mm) | (Nm) | (N) | (Nm) | (N) | (Nm) | (N) | (N)* | (N)* |
| М 6 | 1 | 10 | 9 000 | 14 | 13 200 | 16 | 15 400 | ||
| М 8 | 1,25 | 23 | 16 500 | 34 | 24 200 | 40 | 28 500 | ||
| М 10 | 1,5 | 45 | 26 000 | 67 | 38 500 | 77 | 45 000 | ||
| М 12 | 1,75 | 80 | 38 500 | 115 | 56 000 | 135 | 66 000 | ||
| М 14 | 2 | 125 | 53 000 | 185 | 77 000 | 215 | 90 000 | ||
| М 16 | 2 | 195 | 72 000 | 285 | 106 000 | 335 | 124 000 | ||
| М 18 | 2,5 | 280 | 91 000 | 395 | 129 000 | 465 | 151 000 | ||
| М 20 | 2,5 | 395 | 117 000 | 560 | 166 000 | 655 | 194 000 | ||
| М 22 | 2,5 | 540 | 146 000 | 770 | 208 000 | 900 | 243 000 | ||
| М 24 | 3 | 680 | 168 000 | 970 | 239 000 | 1 130 | 280 000 | 199 000 | 283 000 |
| М 27 | 3 | 1 000 | 221 000 | 1 420 | 315 000 | 1 670 | 370 000 | 261 000 | 372 000 |
| М 30 | 3,5 | 1 360 | 270 000 | 1 930 | 385 000 | 2 260 | 450 000 | 319 000 | 454 000 |
| М 33 | 3,5 | 1 850 | 335 000 | 2 630 | 480 000 | 3 080 | 560 000 | 396 000 | 564 000 |
| М 36 | 4 | 2 380 | 395 000 | 3 380 | 460 000 | 3 960 | 660 000 | 466 000 | 664 000 |
| М 39 | 4 | 559 000 | 797 000 | ||||||
| М42 | 4,5 | 642 000 | 916 000 | ||||||
| М 45 | 4,5 | 750 000 | 1 070 000 | ||||||
| М 48 | 5 | 846 000 | 1 206 000 | ||||||
| М 52 | 5 | 1 013 000 | 1 443 000 | ||||||
| М 56 | 5,5 | 1 170 000 | 1 666 000 | ||||||
| М 64 | 6 | 1 543 000 | 2 198 000 | ||||||
| М 72 | 6 | 2 002 000 | 2 852 000 |