Rosemount 1495 - Appendix B; Bolt Torque Recommendations

Reference Manual
00809-0100-4792, Rev CA
August 2010
Rosemount 1495, 1496
B-12
BOLT TORQUE
RECOMMENDATIONS
The Bolt Torque tables are to be used for reference only, as each installation
must be checked for leaks and tightened as necessary.
The torque required to produce adaquate bolt stress is a function of many
parameters, including but not limited to:
• Diameter of bolt
• Type and # of threads of bolt
• Material of bolt
• Gasket type
• Condition of nut bearing surfaces
• Lubrication of bolt threads and nut bearing surfaces
The following tables are typical torque recommendations by Emerson Gasket
Vendors for use with gaskets provided:
Table B-8. Class 300#
1
/16-in. Non-Asbestos Flat Gasket
Flange Size
in. (mm)
Number of Bolts Bolt Diameter
in. (mm)
Bolt Torque
ft.-lbs. (N-m)
2 (5.08) 8 5/8 (15.9) 52 (71)
2.5 (6.35) 8 3/4 (19.1) 73 (99)
3 (7.62) 8 3/4 (19.1) 106 (144)
4 (10.16) 8 3/4 (19.1) 136 (185)
6 (15.24) 12 3/4 (19.1) 149 (185)
8 (20.32) 12 7/8 (22.2) 246 (335)
10 (25.4) 16 1 (25.4) 261 (355)
12 (30.48) 16 1 1/8 (28.6) 391 (532)
14 (35.56) 20 1 1/8 (28.6) 341 (464)
16 (40.64) 20 1 1/4 (31.8) 488 (664)
18 (45.72) 24 1 1/4 (31.8) 542 (737)
20 (50.8) 24 1 1/4 (31.8) 598 (813)
24 (60.96) 24 1 1/2 (38.1) 927 (1261)
Table B-9. Class 600#
1
/8-in. Thick Spiral Wound Gasket
Flange Size
in. (mm)
Number of Bolts Bolt Diameter
in. (mm)
Bolt Torque
ft.-lbs. (N-m)
2 (5.08) 8 5/8 (15.9) 90 (122)
2.5 (6.35) 8 3/4 (19.1) 150 (203)
3 (7.62) 8 3/4 (19.1) 150 (203)
4 (10.16) 8 7/8 (22.2) 240 (325)
6 (15.24) 12 1 (25.4) 368 (499)
8 (20.32) 12 1 1/8 (28.6) 533 (723)
10 (25.4) 16 1 1/4 (31.8) 750 (1017)
12 (30.48) 20 1 1/4 (31.8) 750 (1017)
14 (35.56) 20 1 3/8 (34.9) 1020 (1383)
16 (40.64) 20 1 1/2 (38.1) 1200 (1627)
18 (45.72) 20 1 5/8 (41.3) 1650 (2237)
20 (50.8) 24 1 5/8 (41.3) 1650 (2237)
24 (60.96) 24 1 7/8 (47.6) 3000 (4067)