Recommended minimum Torque Values are in N-m.
Torque values are applicable for Bolt Materials - ASTM A193 B7, B16 & ASTM A320 L7.
BOLT TORQUING
Flange NPS |
No of Bolts |
Bolt size |
Bolt Stress (MPa) |
Torque N-m μ=0.09 Copperslip |
Torque N-m μ=0.14 Chesterton Nickel |
Torque N-m μ=0.225 Unlubricated |
---|---|---|---|---|---|---|
½'' | 4 | ½ | 276 | 40 | 59 | 90 |
¾'' | 4 | ⅝ | 276 | 79 | 116 | 178 |
1'' | 4 | ⅝ | 276 | 79 | 116 | 178 |
1¼'' | 4 | ⅝ | 276 | 79 | 116 | 178 |
1½'' | 4 | ¾ | 276 | 139 | 203 | 313 |
2'' | 8 | ⅝ | 276 | 79 | 116 | 178 |
2½'' | 8 | ¾ | 276 | 139 | 203 | 313 |
3'' | 8 | ¾ | 276 | 139 | 203 | 313 |
4'' | 8 | ¾ | 276 | 139 | 203 | 313 |
5'' | 8 | ¾ | 310 | 156 | 229 | 352 |
6'' | 12 | ¾ | 310 | 156 | 229 | 352 |
8'' | 12 | ⅞ | 310 | 249 | 366 | 565 |
10'' | 16 | 1 | 276 | 330 | 485 | 748 |
12'' | 16 | 1 ⅛ | 276 | 479 | 708 | 1098 |
14'' | 20 | 1 ⅛ | 276 | 479 | 708 | 1098 |
16'' | 20 | 1 ¼ | 276 | 668 | 992 | 1543 |
18'' | 24 | 1 ¼ | 276 | 668 | 992 | 1543 |
20'' | 24 | 1 ¼ | 310 | 752 | 1116 | 1736 |
24'' | 24 | 1 ½ | 310 | 1329 | 1988 | 3108 |