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U.S. Bolts - Tightening Torques

Recommended bolt torques.

The tightening torques below are for imperial U.S. bolts with tension approximately 70% of yield strength.

US Bolts - Tightening Torques
Size
(in)
Torque (lbf ft)
SAE Grade 2SAE Grade 5SAE Grade 818-8 S/S
CoarseFineCoarseFineCoarseFineCoarseFine
1/4 4 4.7 6.3 7.3 9 10 6.3 7.8
5/16 8 9 13 14 18 20 11 11.8
3/8 15 17 23 26 33 37 20 22
7/16 24 27 37 41 52 58 31 33
1/2 37 41 57 64 80 90 43 45
9/16 53 59 82 91 115 129 57 63
5/8 73 83 112 128 159 180 93 104
3/4 115 138 200 223 282 315 128 124
7/8 129 144 322 355 454 501 194 193
1 188 210 483 541 682 764 287 289
  • 1 inch = 25.4 mm

The values are for slightly lubricated bolts. For dry bolts increase the torques with approximately 30%.

US bolts - tightening torques

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