The ASME B16.5 flange bolt chart shows the number, the diameter and the length of stud bolts required by flanges of different size, surface area (RF or RTJ), and rating, for effective joint connections. 

 

ASME B16.5 FLANGE BOLT CHART

The chart shows the number, the diameter and the length of stud bolts for ASME flanges (by flange NPS and pressure rating, or class).

FLANGE PRESSURE
RATING
Bolts sizes Flange Face FLANGE NOMINAL SIZE
1/2 3/4 1 2 3 4 5 6 8 10 12 14 16 18 20 24
Flange Class 150 Number 4 4 4 4 4 4 4 4 8 8 8 8 8 12 12 12 16 16 20 20
Diameter ½ ½ ½ ½ ½ 5/8 5/8 5/8 5/8 5/8 ¾ ¾ ¾ 7/8 7/8 1 1 1 1/8 1 1/8
Length of Stud Bolts 1/16” RF 4 5 1/4 5 1/4
RTJ 3 4 4 4 4 5
Lth Mach Bolts 1/16” RF 2 2 3 3 3 3 3 1/4 3 1/4 4 4 5 6
Ring No. R15 R17 R19 R22 R25 R29 R33 R36 R40 R43 R48 R52 R56 R59 R64 R68 R72 R76
Flange Class 300 Number 4 4 4 4 4 8 8 8 8 8 8 12 12 16 16 20 20 24 24 24
Diameter ½ 5/8 5/8 5/8 ¾ 5/8 ¾ ¾ ¾ ¾ ¾ ¾ 7/8 1 1 1/8 1 1/8
Length of Stud Bolts 1/16” RF 3 3 4 4 3/4 7 8 9
RTJ 3 4 4 4 1/2 5 5 6 8 10
Lth Mach Bolts 1/16” RF 3 3 8
Ring No. R11 R15 R16 R18 R20 R23 R26 R31 R34 R37 R41 R45 R49 R53 R57 R61 R65 R69 R73 R77
Flange Class 400 Number 4 4 4 4 4 8 8 8 8 8 8 12 12 16 16 20 20 24 24 24
Diameter ½ 5/8 5/8 5/8 ¾ 5/8 ¾ ¾ 7/8 7/8 7/8 7/8 1 1 1/8 1 3/8 1 3/8
Length of Stud Bolts ¼” RF 3 5 6 8 9 10½
M&F / T&G 3 1/2 4 4 8 10¼
RTJ 3 5 6 7 1/2 8 9 11
Ring No. R11 R13 R16 R18 R20 R23 R26 R31 R34 R37 R41 R45 R49 R53 R57 R61 R65 R69 R73 R77
Flange Class 600 Number 4 4 4 4 4 8 8 8 8 8 8 12 12 16 20 20 20 20 24 24
Diameter ½ 5/8 5/8 5/8 ¾ 5/8 ¾ ¾ 7/8 7/8 1 1 1 1/8 1 3/8 1 5/8 15/8 1 7/8
Length of Stud Bolts ¼” RF 3 5 10 10¾ 11¼ 13
M&F / T&G 4 4 9 10½ 11 12¾
RTJ 3 5 10 10¾ 11½ 13¼
Ring No. R11 R13 R16 R18 R20 R23 R26 R31 R34 R37 R41 R45 R49 R53 R57 R61 R65 R69 R73 R77
Flange Class 900 Number 4 4 4 4 4 8 8 8 8 8 12 12 16 20 20 20 20 20 20
Diameter ¾ ¾ 7/8 7/8 1 7/8 1 7/8 1 1/8 1 1/8 1 3/8 1 3/8 1 3/8 1 5/8 1 7/8 2
Length of Stud Bolts ¼” RF 5 5 10 10¾ 11¼ 12¾ 13¾ 17¼
M&F / T&G 4 6 9 10½ 11 12½ 13½ 17
RTJ 5 5 10 11 11½ 13¼ 14¼ 18
Ring No. R12 R14 R16 R18 R20 R24 R27 R31 R37 R41 R45 R49 R53 R57 R62 R66 R70 R74 R78
Flange Class 1500 Number 4 4 4 4 4 8 8 8 8 8 12 12 12 16 16 16 16 16 16
Diameter ¾ ¾ 7/8 7/8 1 7/8 1 1 1/8 1 3/8 1 5/8 1 7/8 2 3
Length of Stud Bolts ¼” RF 5 5 7 10 1/4 11½ 13 1/4 14¾ 16 17½ 19½ 21¼ 24¼
M&F / T&G 4 6 10 11¼ 13 14½ 15¾ 17¼ 19¼ 21 24
RTJ 5 5 7 10½ 12¾ 13½ 15¼ 16¾ 18½ 20¾ 22¼ 25½
Ring No. R12 R14 R16 R18 R20 R24 R27 R35 R39 R44 R46 R50 R54 R58 R63 R67 R71 R75 R79
Flange Class 2500 Number 4 4 4 4 4 8 8 8 8 8 8 12 12 12
Diameter ¾ ¾ 7/8 1 1 1/8 1 1 1/8 2 2
Length of Stud Bolts ¼” RF 5 6 7 10 11¾ 13½ 15 19¼ 21¼
M&F / T&G 11½ 13¼ 14¾ 19 21
RTJ 5 6 7 8 9 10¼ 12¼ 14 15½ 20 22
Ring No. R13 R16 R18 R21 R23 R26 R28 R32 R38 R42 R47 R51 R55 R60

 

Nominal Pipe Size (NPS) Class 150 Class 300 Class 400 Class 600 Class 900 Class 1500 Class 2500 Pipe Size (NPS)
# of Bolts Bolt Diameter Bolt Length # of Bolts Bolt Diameter Bolt Length # of Bolts Bolt Diameter Bolt Length # of Bolts Bolt Diameter Bolt Length # of Bolts Bolt Diameter Bolt Length # of Bolts Bolt Diameter Bolt Length # of Bolts Bolt Diameter Bolt Length
1/2 4 1/2 2 1/4 4 1/2 2 1/2 4 1/2 3 4 1/2 3 4 3/4 4 1/4 4 3/4 4 1/4 4 3/4 4 3/4 1/2
3/4 4 1/2 2 1/2 4 5/8 3 4 5/8 3 1/2 4 5/8 3 1/2 4 3/4 4 1/2 4 3/4 4 1/2 4 3/4 5 3/4
1 4 1/2 2 1/2 4 5/8 3 4 5/8 3 1/2 4 5/8 3 1/2 4 7/8 5 4 7/8 5 4 7/8 5 1/2 1
1 1/4 4 1/2 2 3/4 4 5/8 3 1/4 4 5/8 3 3/4 4 5/8 3 3/4 4 7/8 5 4 7/8 5 4 1 6 1 1/4
1 1/2 4 1/2 2 3/4 4 3/4 3 1/2 4 3/4 4 1/4 4 3/4 4 1/4 4 1 5 1/2 4 1 5 1/2 4 1 1/8 6 3/4 1 1/2
2 4 5/8 3 1/4 8 5/8 3 1/2 8 5/8 4 1/4 8 5/8 4 1/4 8 7/8 5 3/4 8 7/8 5 3/4 8 1 7 2
2 1/2 4 5/8 3 1/2 8 3/4 4 8 3/4 4 3/4 8 3/4 4 3/4 8 1 6 1/4 8 1 6 1/4 8 1 1/8 7 3/4 2 1/2
3 4 5/8 3 1/2 8 3/4 4 1/4 8 3/4 5 8 3/4 5 8 7/8 5 3/4 8 1 1/8 7 8 1 1/4 8 3/4 3
3 1/2 8 5/8 3 1/2 8 3/4 4 1/4 8 7/8 5 1/2 8 7/8 5 1/2 3 1/2
4 8 5/8 3 1/2 8 3/4 4 1/2 8 7/8 5 1/2 8 7/8 5 3/4 8 1 1/8 6 3/4 8 1 1/4 7 3/4 8 1 1/2 10 4
5 8 3/4 3 3/4 8 3/4 4 3/4 8 7/8 5 3/4 8 1 6 1/2 8 1 1/4 7 1/2 8 1 1/2 9 3/4 8 1 3/4 11 3/4 5
6 8 3/4 4 12 3/4 4 3/4 12 7/8 6 12 1 6 3/4 12 1 1/8 7 1/2 12 1 3/8 10 1/4 8 2 13 1/2 6
8 8 3/4 4 1/4 12 7/8 5 1/2 12 1 6 3/4 12 1 1/8 7 1/2 12 1 3/8 8 3/4 12 1 5/8 11 1/2 12 2 15 8
10 12 7/8 4 1/2 16 1 6 1/4 16 1 1/8 7 1/2 16 1 1/4 8 1/2 16 1 3/8 9 1/4 12 1 7/8 13 1/4 12 2 1/2 19 1/4 10
12 12 7/8 4 3/4 16 1 1/8 6 3/4 16 1 1/4 8 20 1 1/4 8 3/4 20 1 3/8 10 16 2 14 3/4 12 2 3/4 21 1/4 12
14 12 1 5 1/4 20 1 1/8 7 20 1 1/4 8 1/4 20 1 3/8 9 1/4 20 1 1/2 10 3/4 16 2 1/4 16 14
16 16 1 5 1/4 20 1 1/4 7 1/2 20 1 3/8 8 3/4 20 1 1/2 10 20 1 5/8 11 1/4 16 2 1/2 17 1/2 16
18 16 1 1/8 5 3/4 24 1 1/4 7 3/4 24 1 3/8 9 20 1 5/8 10 3/4 20 1 7/8 12 3/4 16 2 3/4 19 1/4 18
20 20 1 1/8 6 1/4 24 1 1/4 8 24 1 1/2 9 1/2 24 1 5/8 11 1/4 20 2 13 3/4 16 3 21 1/4 20
22 20 1 1/4 6 1/2 24 1 1/2 8 3/4 24 1 5/8 10 24 1 5/8 12 22
24 20 1 1/4 6 3/4 24 1 1/2 9 24 1 3/4 10 1/2 24 1 7/8 13 20 2 1/2 17 1/4 16 3 1/2 24 1/4 24

EN 1092-1 FLANGE BOLT CHART

The number, the length and the diameter of stud bolts for European flanges (EN 1092-1) are shown on these pages:

 

FLANGE BOLT TORQUE CHART ASTM A193 (B7, B16, B8)

Flange bolt torque wrenchThe flange bolt torque chart shows the recommended torque to be applied to flange bolts in ft x lbs or NM, depending on the stud bolt grade and diameter. The torque values are shown in three steps (30%, 70%, and 100%) and are only indicative, as the conditions of the specific application should be carefully evaluated.

TORQUE CHART ASTM 193 GRADE B7 AND ASTM 193 GRADE B16 STUD BOLTS

STUD BOLT
OD
BOLT TORQUE in Foot x Lbs
30% Initial
Torque
70%
Torque
100% Final
Torque
1/2 17 39 55
9/16 24 55 80
5/8 33 77 110
3/4 59 137 195
7/8 93 217 310
1 140 325 465
1⅛ 205 480 685
288 672 960
1⅜ 391 915 1305
518 1208 1725
19/16 588 1372 1960
1⅝ 668 1558 2225
840 1960 2800
1⅞ 1044 2436 3480
2 1280 2985 4265
1850 4315 6165
2565 5985 8550
3121 7282 10400
3 4080 9520 13600

 

STUD BOLT
OD
TORQUE in NEWTON METER
30% Start
Torque
70%
Torque
100% Final
Torque
1/2 23 53 75
9/16 33 75 108
5/8 45 104 149
3/4 80 186 264
7/8 126 294 420
1 190 441 630
1⅛ 278 651 929
390 911 1302
1⅜ 530 1241 1769
702 1638 2339
19/16 797 1860 2657
1⅝ 906 2112 3017
1139 2657 3796
1⅞ 1415 3303 4718
2 1735 4047 5783
2508 5850 8359
3478 8115 11592
4232 9873 14101
3 5532 12907 18439

 

TORQUE CHART FOR ASTM A193, ASTM A320 GRADE B8 CL2 STUD BOLTS (HIGH TEMPERATURE SERVICE)

STUD BOLT
OD
BOLT TORQUE in Foot x Lbs
30% Start
Torque
70%
Torque
100% Final
Torque
1/2 16 36 52
9/16 23 53 75
5/8 31 73 104
3/4 55 129 184
7/8 71 166 237
1 107 249 356
1⅛ 127 297 424
179 417 596
1⅜ 186 435 622
246 574 821
19/16 168 392 560
1⅝ 191 445 636
240 561 801
1⅞ 298 696 994
2 366 853 1219
529 1234 1762
733 1709 2442
986 2300 3285
3 1289 3008 4297BOLT

 

STUD BOLT
OD
TORQUE in NEWTON METER
30% Start
Torque
70%
Torque
100% Final
Torque
1/2 22 49 71
9/16 31 72 102
5/8 42 99 141
3/4 75 175 249
7/8 96 225 321
1 145 338 483
1⅛ 172 403 575
243 565 808
1⅜ 252 590 843
334 778 1113
19/16 228 531 759
1⅝ 259 603 862
325 761 1086
1⅞ 404 944 1348
2 496 1157 1653
717 1673 2389
994 2317 3311
1337 3118 4454
3 1748 4078 5826

 

TORQUE CHART ASTM A193, ASTM A320 GRADE B8 CL2 STUD BOLTS (LOW TEMPERATURE SERVICE)

STUD BOLT
OD
BOLT TORQUE in Foot x Lbs
30% Start
Torque
70%
Torque
100% Final
Torque
1/2 22 51 73
9/16 32 74 105
5/8 44 102 145
3/4 77 180 257
7/8 100 232 332
1 149 348 498
1⅛ 178 415 593
250 584 834
1⅜ 261 609 870
345 804 1149
19/16 235 549 784
1⅝ 267 624 891
336 785 1121
1⅞ 418 974 1392
2 512 1194 1706
740 1727 2467
1026 2393 3419
1380 3219 4599
3 1805 4211 6015

 

STUD BOLT
OD
TORQUE in NEWTON METER
30% Start
Torque
70%
Torque
100% Final
Torque
1/2 30 69 99
9/16 43 100 142
5/8 60 138 197
3/4 104 244 348
7/8 136 315 450
1 202 472 675
1⅛ 241 563 804
339 792 1131
1⅜ 354 826 1180
468 1090 1558
19/16 319 744 1063
1⅝ 362 846 1208
456 1064 1520
1⅞ 567 1321 1887
2 694 1619 2313
1003 2341 3345
1391 3244 4636
1871 4364 6235
3 2447 5709 8155