The following table gives torque values for 17D and 6BX flange bolts with fluoropolymer coating for subsea applications:
| Bolt Size | Hex Nut Size Across Flats | Bolt Tension lbf (Min. 67% Yield Stress) | Make Up Torque Ft Lbs (Min. 67% Yield Stress) | Bolt Tension lbf (Max 73% Yield Stress) | Make Up Torque Ft Lbs (Max 73% Yield Stress) |
| 3/4 – 10 UNC | 1-1/4 | 23,530 | 160 | 24,538 | 174 |
| 7/8 – 9 UNC | 1-7/16 | 32,483 | 253 | 33,937 | 275 |
| 1 – 8 UN | 1-5/8 | 42,614 | 376 | 44,522 | 409 |
| 1-1/8 – 8 UN | 1-13/16 | 55,608 | 539 | 58,098 | 588 |
| 1-1/4 – 8 UN | 2 | 70,330 | 744 | 73,478 | 810 |
| 1-3/8 – 8 UN | 2-3/16 | 86,777 | 994 | 90,662 | 1,083 |
| 1-1/2 – 8 UN | 2-3/8 | 104,951 | 1,294 | 109,650 | 1,410 |
| 1-5/8 – 8 UN | 2-9/16 | 124,852 | 1,649 | 130,442 | 1,797 |
| 1-3/4 – 8 UN | 2-3/4 | 146,480 | 2,063 | 153,038 | 2,247 |
| 1-7/8 – 8 UN | 2-15/16 | 169,833 | 2,541 | 177,438 | 2,768 |
| 2 – 8 UN | 3-1/8 | 194,914 | 3,087 | 203,642 | 3,363 |
| 2-1/4 – 8 UN | 3-1/2 | 250,256 | 4,402 | 261,461 | 4,796 |
| 2-1/2 – 8 UN | 3-7/8 | 312,504 | 6,044 | 326,497 | 6,586 |
| 2-3/4 – 8 UN** | 4-1/4 | 345,310 | 7,284 | 360,772 | 7,937 |
| 3 – 8 UN** | 4-5/8 | 414,127 | 9,443 | 432,670 | 10,289 |
| 3-1/4 – 8 UN** | 5 | 489,194 | 12,013 | 511,098 | 13,088 |
ASTM A320 L7 bolts using ASTM A194 GR. 2H nuts with Fluoropolymer coating (Coefficient of Friction = 0.07).
**Torque calculated same as above based on reduced yield strength of 95,000 psi.
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