# Flange Bolting Torque Table 2A

The torque tables are built on specific assumptions regarding bolt and nut factor. Before using a given torque table, these assumptions should be verified to insure they are appropriate for the specific application.

Even if all assumptions are appropriate, results may vary depending on actual conditions. Many factors induce scatter in the results or increase the inherent variability in the bolting process. These include variations in the nut factor; bolt, flange and nut condition; equipment calibration and condition; perpendicularity of the bolt, nut and flange; etc.

The values in the tables are based on the equation..

 T = Torque value, (ft-lbs) F = Bolt pre-load, (lbs) k = Nut Factor based on lubricant used d = Nominal bolt diameter, (in.)

The nut factor is not the coefficient of friction.
It is an experimentally derived constant that includes the impact of friction.

ft-lbs to nm = 0.737562149277
nm to ft-lbs = 1.3558179

 Table 2A / Torque FT-LBS - Cold Service ASTM A320 Grade L7 Stud Bolts BOLT DIA Torque Ft*lb 30% Initial Torque 70% Torque 100% Final Torque 1/2 23 54 76 9/16 33 77 110 5/8 46 107 152 3/4 81 189 270 7/8 131 305 436 1 196 457 653 1.1/8 287 671 958 1.1/4 404 943 1348 1.3/8 854 1279 1828 1.1/2 725 1689 2413 1.9/16 824 1922 2746 1.5/8 935 2183 3118 1.3/4 1177 2747 3924 1.7/8 1461 3410 4871 2 1792 4180 5972 2.1/4 2590 6044 8635 2.1/2 3590 8376 11966

 Table 2A / Torque Nm - Cold Service ASTM A320 Grade L7 Stud Bolts BOLT DIA Torque N*m 30% Initial Torque 70% Torque 100% Final Torque 1/2 31 73 103 9/16 45 104 149 5/8 62 145 206 3/4 110 256 366 7/8 178 414 591 1 266 620 885 1.1/8 389 910 1299 1.1/4 548 1279 1828 1.3/8 1158 1734 2478 1.1/2 983 2290 3272 1.9/16 1117 2606 3723 1.5/8 1268 2960 4227 1.3/4 1596 3724 5320 1.7/8 1981 4623 6604 2 2430 5667 8097 2.1/4 3512 8195 11707 2.1/2 4867 11356 16224

Notes..

• Bolting torque to develop 70% Bolt Yield Stress at Nut Factor, K=0.16
• This Table is applicable to Never-Seize paste and Fel-Pro lubricant, K=0.16.
• The above Table is applicable only for ASTM A320 Grade L7.
• The torque values are approved for spiral wound graphite and PTFE filled gaskets.
• The Final Torque Value accounts for 10% bolt relaxation.
• This Table is not acceptable for PTFE coated Stud Bolts and nuts, for these refer to Table 5A.

OTHER BOLTING TORQUE TABLES

BOLTING TORQUE TABLE 1 - ASTM A193 AND ASTM A320 GRADE B8, CL2 STUD BOLTS

BOLTING TORQUE TABLE 1A - COLD SERVICE ASTM A193 AND ASTM A320 GRADE B8, CL2 STUD BOLTS

BOLTING TORQUE TABLE 2 - ASTM 193 GRADE B7 AND ASTM 193 GRADE B16 STUD BOLTS

BOLTING TORQUE TABLE 2A - COLD SERVICE ASTM A320 GRADE L7 STUD BOLTS

BOLTING TORQUE TABLE 3 - USE ONLY WITH A193 B8, CL1 BOLTS AT 540°C - 650°C ON UNINSULATED FLANGES

BOLTING TORQUE TABLE 4 - USE ONLY WITH 6061-T6 ALUMINIUM FLANGES

BOLTING TORQUE TABLE 5 - PTFE COATED ASTM A193 B7 and ASTM 193 B16 STUD BOLTS

BOLTING TORQUE TABLE 5A - COLD SERVICE PTFE COATED ASTM A320 GRADE L7 STUD BOLTS

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