Bolt Torque Values for ASME B16.5 Series A Class 150# Flat Flanges
with A193 Grade B7 Bolts
For Full Face Homogenous Elastomeric Gaskets
<70 durometer Shore A | >70 durometer Shore A | ||||
Nominal Pipe Size (in) | # of Bolt Holes (in) | Size of Bolts (in) | Minimum Torque (ft. lbs.) | Preferred Torque (ft. lbs.) | Preferred Torque (ft. lbs.) |
0.50 | 4 | 0.50 | 9 | 14 | 19 |
0.75 | 4 | 0.50 | 12 | 17 | 23 |
1.00 | 4 | 0.50 | 14 | 21 | 28 |
1.25 | 4 | 0.50 | 16 | 24 | 32 |
1.50 | 4 | 0.50 | 19 | 28 | 37 |
2.00 | 4 | 0.63 | 33 | 49 | 66 |
2.50 | 4 | 0.63 | 45 | 67 | 90 |
3.00 | 4 | 0.63 | 49 | 73 | 97 |
3.50 | 8 | 0.63 | 30 | 45 | 60 |
4.00 | 8 | 0.63 | 33 | 49 | 66 |
5.00 | 8 | 0.75 | 41 | 61 | 82 |
6.00 | 8 | 0.75 | 46 | 69 | 92 |
8.00 | 8 | 0.75 | 66 | 99 | 132 |
10.0 | 12 | 0.88 | 64 | 96 | 128 |
12.0 | 12 | 0.88 | 93 | 140 | 186 |
14.0 | 12 | 1.00 | 134 | 201 | 268 |
16.0 | 16 | 1.00 | 120 | 181 | 241 |
18.0 | 16 | 1.13 | 132 | 198 | 264 |
20.0 | 20 | 1.13 | 124 | 187 | 249 |
24.0 | 20 | 1.25 | 173 | 260 | 347 |
Bolt Torque Values for ASME B16.47 Series A Class 150# Flat Flanges
with A193 Grade B7 Bolts
For Full Face Homogenous Elastomeric Gaskets
<70 durometer Shore A | >70 durometer Shore A | ||||
Nominal Pipe Size (in) | # of Bolt Holes (in) | Size of Bolts (in) | Minimum Torque (ft. lbs.) | Preferred Torque (ft. lbs.) | Preferred Torque (ft. lbs.) |
26 | 24 | 1.25 | 238 | 238 | 318 |
28 | 28 | 1.25 | 224 | 224 | 299 |
30 | 28 | 1.25 | 248 | 248 | 331 |
32 | 28 | 1.50 | 309 | 309 | 412 |
34 | 32 | 1.50 | 283 | 283 | 377 |
36 | 32 | 1.50 | 309 | 309 | 411 |
38 | 32 | 1.50 | 356 | 356 | 474 |
40 | 36 | 1.50 | 328 | 328 | 438 |
42 | 36 | 1.50 | 354 | 354 | 472 |
44 | 40 | 1.50 | 339 | 339 | 452 |
46 | 40 | 1.50 | 354 | 354 | 473 |
48 | 44 | 1.50 | 342 | 342 | 456 |
50 | 44 | 1.75 | 470 | 470 | 626 |
52 | 44 | 1.75 | 502 | 502 | 669 |
54 | 44 | 1.75 | 535 | 535 | 713 |
56 | 48 | 1.75 | 528 | 528 | 705 |
58 | 48 | 1.75 | 561 | 561 | 747 |
60 | 52 | 1.75 | 530 | 530 | 707 |
NOTE 1: This torque table applies for 1/16” and 1/8” thick homogenous elastomeric gaskets. The pressure rating of the material may vary depending on the grade.
NOTE 2: The above-mentioned torque values are based on the maximum bolt stress of 60,000 psi. Bolt yield should be at least 80,000 psi.
NOTE 3: This table does not take flange strength into consideration. We recommend consulting the flange manufacturer to confirm the suitability of the above-mentioned values.
NOTE 4: Apply torque in increments. When the gasket extends past the O.D. of the flange by 1/4:” to 3/8”, stop tightening.
TORQUE
After installing a new gasket or seal it’s essential to tighten the fasteners with a torque wrench that’s been recently calibrated. Without this it’s impossible to know if the joint has been tightened to the required level. Friction between the nut, washers, flange faces and thread increases the torque measured at the wrench, possibly resulting in insufficient clamping force being applied to the gasket. Avoid this by applying a thin, uniform coating of high quality lubricant to the underside of bolt heads, nuts and washers and the thread itself. Take care to keep it off the gasket.