17-7 PH® Flange Bolting

17-7PH® Stainless Steel is a semi-austenitic precipitation-hardening stainless steel, well-suited for applications requiring high strength and hardness, good fatigue properties, corrosion resistance, and minimum distortion upon heat treatment. 17-7 PH® Stainless Steel, when stressed and exposed to corrosive environments, may be subject to spontaneous fracture. (Registered trademark of AK Steel)

Help eliminate flange leakage with BelleFlex® flange bolting. Leaks occur by bolt stretch, gasket creep, cycles of thermal change, etc. However, by maintaining load on bolted joints, leakage is greatly reduced, if not eliminated. 

The load values listed in the table below are according to the calculated theoretical load curve based on the dimensions and material for each part number.

Part NumberBolt SizeFlat Load
lb
Torque *
ft-lb
FB1-30-71/2"431430
FB1-45-71/2"643245
FB1-60-71/2"857360
FB2-30-75/8"691260
FB2-45-75/8"1024790
FB2-60-75/8"13728120
FB3-30-73/4"10113100
FB3-45-73/4"15183150
FB3-60-73/4"20224200
FB4-30-77/8"14037160
FB4-45-77/8"20805240
FB4-60-77/8"27992320
FB5-30-71"18288245
FB5-45-71"27367368
FB5-60-71"36548490
FB6-30-71-1/8"23804355
FB6-45-71-1/8"35756533
FB6-60-71-1/8"47443710
FB7-30-71-1/4"30093500
FB7-45-71-1/4"45004750
FB7-60-71-1/4"602091000
FB8-30-71-3/8"37162680
FB8-45-71-3/8"556341020
FB8-60-71-3/8"740881360
FB9-30-71-1/2"44802800
FB9-45-71-1/2"675011200
FB9-60-71-1/2"896551600
FB10-30-71-5/8"834821100
FB10-45-71-5/8"803671650
FB10-60-71-5/8"1073412200
FB11-30-71-3/4"628081500
FB11-45-71-3/4"936312250
FB11-60-71-3/4"1251113000
FB12-30-71-7/8"725582000
FB12-45-71-7/8"1087493000
FB12-60-71-7/8"120702 4000
FB13-30-72"834582200
FB13-45-72"1249613300
FB13-60-72"138918 4400
FB14-30-72-1/4"1068163180
FB14-45-72-1/4"1602794770
FB14-60-72-1/4"178104 6360
FB15-30-72-1/2"1332184400
FB15-45-72-1/2"2004336600
FB15-60-72-1/2"222410 8800
FB16-30-72-3/4"1633005920
FB16-45-72-3/4"2450128880
FB16-60-72-3/4"272300 11840
FB17-30-73"1953497720
FB17-45-73"29373511580
FB17-60-73"325682 15440

* Torque values for sizes 1-1/8″ and larger are based on the 8-pitch thread series for flanged piping.
† 50,000 psi bolt stress