# Flange Bolting Torque Table 3

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 3 / Torque FT-LBS - Use only with A193 B8, CL1 Bolts at 540°C - 650°C on uninsulated flanges BOLT DIA Torque Ft*lb 30% Initial Torque 70% Torque 100% Final Torque 1/2 5 10 15 9/16 5 15 20 5/8 10 20 25 3/4 15 35 50 7/8 25 55 80 1 35 90 125 1.1/8 50 125 175 1.1/4 75 175 250 1.3/8 100 235 335 1.1/2 135 315 450 1.9/16 150 350 500 1.5/8 170 400 575 1.3/4 215 505 725 1.7/8 270 630 900 2 330 770 1100 2.1/4 475 1115 1590 2.1/2 660 1540 2200 2.3/4 885 2065 2950 3 1160 2705 3865

 Table 3 / Torque Nm - Use only with A193 B8, CL1 Bolts at 540°C - 650°C on uninsulated flanges BOLT DIA Torque N*m 30% Initial Torque 70% Torque 100% Final Torque 1/2 7 14 20 9/16 7 20 27 5/8 14 27 34 3/4 20 47 68 7/8 34 75 108 1 47 122 169 1.1/8 68 169 237 1.1/4 102 237 339 1.3/8 136 319 454 1.1/2 183 427 610 1.9/16 203 475 678 1.5/8 230 542 780 1.3/4 292 685 983 1.7/8 366 854 1220 2 447 1044 1491 2.1/4 644 1512 2156 2.1/2 895 2088 2983 2.3/4 1200 2800 4000 3 1573 3667 5240

Notes..

• Bolting torque to develop 45% 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 A193 Grade B8, Class 1 Stud Bolts for use in temperatures above 1000°F (540°C), and up to and including 1200°F (650°C), installed on uninsulated flanges. The values are based on yield strength at ambient temperature.
• The torque values are approved for spiral wound graphite filled gaskets, graphite sheet gaskets GHE and GHR types, ring joint, double jacketed and Camprofile gaskets with graphite lining.
• The Final Torque Value accounts for 10% bolt relaxation.

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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