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 | 310 | 89 | 130 | 200 |
1½'' | 4 | ¾ | 276 | 139 | 203 | 313 |
2'' | 8 | ⅝ | 310 | 89 | 130 | 200 |
2½'' | 8 | ¾ | 276 | 139 | 203 | 313 |
3'' | 8 | ¾ | 310 | 156 | 229 | 352 |
4'' | 8 | ⅞ | 310 | 249 | 366 | 565 |
5'' | 8 | 1 | 310 | 371 | 545 | 842 |
6'' | 12 | 1 | 310 | 371 | 545 | 842 |
8'' | 12 | 1 ⅛ | 310 | 539 | 797 | 1235 |
10'' | 16 | 1 ¼ | 310 | 752 | 1116 | 1736 |
12'' | 20 | 1 ¼ | 310 | 752 | 1116 | 1736 |
14'' | 20 | 1 ⅜ | 310 | 1014 | 1511 | 2356 |
16'' | 20 | 1 ½ | 310 | 1329 | 1988 | 3108 |
18'' | 20 | 1 ⅝ | 310 | 1704 | 2555 | 4002 |
20'' | 24 | 1 ⅝ | 310 | 1704 | 2555 | 4002 |
24'' | 24 | 1 ⅞ | 310 | 2656 | 4000 | 6286 |