ORIFICE FLANGES

DEFINITION
 

orifice flange ASME  Orifice flanges are used instead of standard pipe flanges when an orifice plate or flow nozzle has to be installed. Pairs of pressure tappings are machined into the orifice flange, making separate orifice carriers or tappings in the pipe wall unnecessary. The range of orifice flanges covers all standard sizes and ranges, and all common flange materials. Flanges are available in socket weld or weld neck form, and are typically supplied with two ½” NPT tappings in each flange. Jacking screws to ensure ease of removal of the primary flow element are provided.

 

DIMENSIONS WN ORIFICE FLANGES ASME B16.36

ORIFICE RF | ORIFICE RTJ

WN ORIFICE FLANGE / RF

GENERAL COMMENTS:

  • Dimensions are in millimeters (excluding bolts and bolt holes).

  • Different NPT sizes than 1/2 may be supplied

  • Bolt lengths for RF flanges include allowance for orifice and gasket thickness of 6 mm (0.25 in.) for NPS 1 to NPS 12. Bolt lengths for ring-type joint flanges include allowance of 15 mm (0.62 in.) for NPS 1 to NPS 3.

  • Bore (B) has to be specified by the buyer

  • Stud Bolt lenghts excl. the height of the chamfers


CLASS 300 WELD NECK ORIFICE FLANGE RF

Orifice Flanges WN RF Dimensions

NPS A R O T H X Tg
1 33.4 50.8 125 36.6 81 54 6.4
48.3 73 155 36.6 84 70 6.4
2 60.3 92.1 165 36.6 84 84 6.4
73 104.8 190 36.6 87 100 6.4
3 88.9 127 210 36.6 87 117 9.5
4 114.3 157.2 255 36.6 90 146 12.7
6 168.3 215.9 320 36.6 98 206 12.7
8 219.1 269.9 380 39.7 110 260 12.7
10 273 323.8 445 46.1 116 321 12.7
12 323.8 381 520 49.3 129 375 12.7
14 355.6 412.8 585 52.4 141 425 12.7
16 406.4 469.9 650 55.6 144 483 12.7
18 457 533.4 710 58.8 157 533 12.7
20 508 584.2 775 62 160 587 12.7
24 610 692.2 915 68.3 167 702

12.7

 

NPS BOLT CIRCLE DIAM. BOLTS # HOLES DIAM. BOLTS DIAMETER BOLTS LENGHT
1 88.9 4 11/16  5/8 125
114.3 4 13/16  3/4 135
2 127 8 11/16  5/8 125
149.2 8 13/16  3/4 135
3 168.3 8 13/16  3/4 135
4 200 8 13/16  3/4 135
6 269.9 12 7/8  3/4 135
8 330.2 12 1  7/8 145
10 387.4 16 1 1/8 1    165
12 450.8 16 1 1/8 180
14 514.4 20 1 1/8 185
16 571.5 20 1 3/8 195
18 628.6 24 1 3/8 205
20 685.8 24 1 3/8 215
24 812.8 24 1 3/8

240

 

COMMENTS: Height of Raised Face (RF) in CLASS 300 is 2 mm
 

CLASS 600 WELD NECK ORIFICE FLANGE RF

Orifice Flanges WN RF Dimensions

NPS A R O T H X Tg
1 33.5 50.8 125 36.6 81 54 6.4
48.3 73 155 36.6 84 70 6.4
2 60.3 92.1 165 36.6 84 84 6.4
73 104.8 190 36.6 87 100 6.4
3 88.9 127 210 36.6 87 117 9.5
4 114.3 157.2 275 38.1 102 152 12.7
6 168.3 215.9 355 47.7 117 222 12.7
8 219.1 269.9 420 55.6 133 273 12.7
10 273 323.8 510 63.5 152 343 12.7
12 323.8 381 560 66.7 156 400 12.7
14 355.6 412.8 605 69.9 165 432 12.7
16 406.4 469.9 685 76.2 178 495 12.7
18 457.2 533.4 745 82.6 184 546 12.7
20 508 584.2 815 88.9 190 610 12.7
24 609.6 692.2 940 101.6 203 718

12.7

 

NPS BOLT CIRCLE DIAM. BOLTS # HOLES DIAM. BOLTS DIAMETER BOLTS LENGHT
1 88.9 4 11/16 5/8 125
114.3 4 13/16 3/4 135
2 127 8 11/16 5/8 125
149.2 8 13/16 3/4 135
3 168.3 8 13/16 3/4 135
4 215.9 8 1 7/8 150
6 292.1 12 1 1/8 1 180
8 349.2 12 1 1/8 195
10 431.8 16 1 3/8 220
12 489 20 1 3/8 230
14 527 20 1 3/8 240
16 603.2 20 1 5/8 260
18 654 20 1 3/4 1 5/8 280
20 723.9 24 1 3/4 1 5/8 300
24 838.2 24 2 1 5/8 335

 

COMMENTS: Height of Raised Face (RF) in CLASS 600 is 2 mm at NPS 1 - NPS 3, and 7 mm at NPS 4 - NPS 24.


CLASS 900 WELD NECK ORIFICE FLANGE RF

Orifice Flanges WN RF Dimensions

NPS R O T H X A Tg
1 50.8 125 36.6 81 54 33.5 6.4
73 155 36.6 84 70 48.3 6.4
2 92.1 165 36.6 84 84 60.3 6.4
104.8 190 36.6 87 100 73 6.4
3 127 240 38.1 102 127 88.9 9.5
4 157.2 290 44.5 114 159 114.3 12.7
6 215.9 380 55.6 140 235 168.3 12.7
8 269.9 470 63.5 162 298 219.1 12.7
10 323.8 545 69.9 184 368 273 12.7
12 381 610 79.4 200 419 323.8 12.7
14 412.8 640 85.8 213 451 355.6 12.7
16 469.9 705 88.9 216 508 406.4 12.7
18 533.4 785 101.6 229 565 457.2 12.7
20 584.2 855 108 248 622 508 12.7
24 692.2 1040 139.7 292 749 609.6 12.7

 

NPS BOLT CIRCLE DIAM. BOLTS # HOLES DIAM. BOLTS DIAMETER BOLTS LENGHT
1 88.9 4 11/16 5/8 125
114.3 4 13/16 3/4 135
2 127 8 11/16 5/8 125
149.2 8 13/16 3/4 135
3 190.5 8 1 7/8 150
4 235 8 1 1/8 180
6 317.5 12 1 1/8 195
8 393.7 12 1 3/8 230
10 469.9 16 1 3/8 240
12 533.4 20 1 3/8 260
14 558.8 20 1 5/8 280
16 616 20 1 3/4 1 5/8 290
18 685.8 20 2 1 7/8 330
20 749.3 20 2 1/8 2 355
24 901.7 20 2 1/8 445

 

COMMENTS: Height of Raised Face (RF) in CLASS 900 is 7 mm.
 

CLASS 1500 WELD NECK ORIFICE FLANGE RF

Orifice Flanges WN RF Dimensions

NPS R O T H X A Tg
1 50.8 150 38.1 83 52 33.5 6.4
73 180 38.1 89 70 48.3 6.4
2 92.1 215 38.1 102 105 60.3 6.4
104.8 245 41.3 105 124 73 6.4
3 127 265 47.7 117 133 88.9 9.5
4 157.2 310 54 124 162 114.3 12.7
6 215.9 395 82.6 171 229 168.3 12.7
8 269.9 485 92.1 213 292 219.1 12.7
10 323.8 585 108 254 368 273 12.7
12 381 675 123.9 283 451 323.8 12.7
14 412.8 750 133.4 298 495 355.6 12.7
16 469.9 825 146.1 311 552 406.4 12.7
18 533.4 915 162 327 597 457.2 12.7
20 584.2 985 177.8 356 641 508 12.7
24 692.2 1170 203.2 406 762 609.6 12.7

 

NPS BOLT CIRCLE DIAM. BOLTS # HOLES DIAM. BOLTS DIAMETER BOLTS LENGHT
1 101.6 4 1 7/8 150
123.8 4 1 1/8 160
2 165.1 8 1 7/8 150
190.5 8 1 1/8 1 165
3 203.2 8 1 1/8 185
4 241.3 8 1 3/8 205
6 317.5 12 1 3/8 265
8 393.7 12 1 3/4 1 5/8 300
10 482.6 12 2 1 7/8 345
12 571.6 16 2 1/8 2 380
14 635 16 2 3/8 415
16 704.8 16 2 5/8 450
18 774.7 16 2 7/8 2 3/4 500
20 831.8 16 3 1/8 3 545
24 990.6 16 3 5/8 620

 

COMMENTS: Height of Raised Face (RF) in CLASS 1500 is 7 mm

CLASS 2500 WELD NECK ORIFICE FLANGE RF

Orifice Flanges WN RF Dimensions

NPS R O T H X A Tg
1 50.8 160 38.1 92 57 33.5 6.4
73 205 44.5 111 79 48.3 6.4
2 92.1 235 50.8 127 95 60.3 6.4
104.8 265 57.2 143 114 73 6.4
3 127 305 66.7 168 133 88.9 9.5
4 157.2 355 76.2 190 165 114.3 12.7
6 215.9 485 108 273 235 168.3 12.7
8 269.9 550 127 318 305 219.1 12.7
10 323.8 675 165.1 419 375 273 12.7
12 381 760 184.2 464 441 323.8 12.7

 

NPS BOLT CIRCLE DIAM. BOLTS # HOLES DIAM. BOLTS DIAMETER BOLTS LENGHT
1 108 4 1 7/8 150
146 4 1 1/8 180
2 171.4 8 1 1/8 1 185
196.8 8 1 1/8 205
3 228.6 8 1 3/8 230
4 273 8 1 5/8 260
6 368.3 8 2 1/8 2 350
8 438.2 12 2 1/8 2 385
10 539.8 12 2 5/8 490
12 619.1 12 2 7/8 2 3/4 540

 

COMMENTS: Height of Raised Face (RF) in CLASS 2500 is 7 mm.

 

WN ORIFICE FLANGE / RTJ

COMMENTS:

  • Dimensions are in millimeters (excl. bolts and bolt holes)
  • Other NPT sizes than 1/2 may be supplied
  • Bolt lengths for raised face flanges include allowance for orifice and gasket thickness of 6 mm (0.25 in.) for NPS 1 to NPS 12 and 10 mm (0.38 in.) for NPS 14 to NPS 24. Bolt lengths for ring-type joint flanges include allowance of 15 mm (0.62 in.) for NPS 1 to NPS 10, 19 mm (0.75 in.) for NPS 12 to NPS 18, and 22 mm (0.88 in.) for NPS 20.
  • Bore (B) is to be specified by the buyer
  • Stud Bolt lenghts excl. the height of the chamfers
     

CLASS 600 WELD NECK ORIFICE RTJ

Orifice Flanges RTJ Dimensions

NPS O T H GROOVE # P E
1 125 36.6 81 R16 50.8 6.35
155 36.6 84 R20 68.27 6.35
2 165 36.6 84 R23 82.55 7.92
190 36.6 87 R26 101.6 7.92
3 210 36.6 87 R31 123.83 7.92
4 275 38.1 102 R37 149.23 7.92
6 355 47.7 117 R45 211.12 7.92
8 420 55.6 133 R49 269.88 7.92
10 510 63.5 152 R53 323.85 7.92
12 560 66.7 156 R57 381 7.92
14 605 69.9 165 R61 419.1 7.92
16 685 76.2 178 R65 469.9 7.92
18 745 82.6 184 R69 533.4 7.92
20 815 88.9 190 R73 584.2 9.53
24 940 101.6 203 R77 692.15 11.13

 

NPS F R W X A Tg
1 8.74 0.8 25.4 54 33.5 6.4
8.74 0.8 25.4 70 48.3 6.4
2 11.91 0.8 27 84 60.3 6.4
11.91 0.8 27 100 73 6.4
3 11.91 0.8 27 117 88.9 9.5
4 11.91 0.8 27 152 114.3 12.7
6 11.91 0.8 27 222 168.3 12.7
8 11.91 0.8 27 273 219.1 12.7
10 11.91 0.8 27 343 273 12.7
12 11.91 0.8 27 400 323.8 12.7
14 11.91 0.8 27 432 355.6 12.7
16 11.91 0.8 30.2 495 406.4 12.7
18 11.91 0.8 30.2 546 457.2 12.7
20 13.49 1.5 31.8 610 508 12.7
24 16.66 1.5 36.5 718 609.6 12.7

 

CLASS 900 WELD NECK ORIFICE RTJ

Orifice Flanges RTJ Dimensions

 

NPS T H GROOVE # P E
1 125 36.6 81 R16 50.8 6.35
155 36.6 84 R20 68.27 6.35
2 165 36.6 84 R23 82.55 7.92
190 36.6 87 R26 101.6 7.92
3 240 38.1 102 R31 123.83 7.92
4 290 44.5 114 R37 149.23 7.92
6 380 55.6 140 R45 211.12 7.92
8 470 63.5 162 R49 269.88 7.92
10 545 69.9 184 R53 323.85 7.92
12 610 79.4 200 R57 381 7.92
14 640 85.8 213 R62 419.1 11.13
16 705 88.9 216 R66 469.9 11.13
18 785 101.6 229 R70 533.4 12.7
20 855 108 248 R74 584.2 12.7
24 1040 139.7 292 R78 692.15 15.88

 

NPS F R W X A Tg
1 8.74 0.8 25.4 54 33.5 6.4
8.74 0.8 25.4 70 48.3 6.4
2 11.91 0.8 27 84 60.3 6.4
11.91 0.8 27 100 73 6.4
3 11.91 0.8 27 127 88.9 9.5
4 11.91 0.8 27 159 114.3 12.7
6 11.91 0.8 27 235 168.3 12.7
8 11.91 0.8 27 298 219.1 12.7
10 11.91 0.8 27 368 273 12.7
12 11.91 0.8 27 419 323.8 12.7
14 16.66 1.5 33.3 451 355.6 12.7
16 16.66 1.5 36.5 508 406.4 12.7
18 19.84 1.5 39.7 565 457.2 12.7
20 19.84 1.5 39.7 622 508 12.7
24 26.97 2.4 47.6 749 609.6 12.7

 

CLASS 1500 WELD NECK ORIFICE RTJ

Orifice Flanges RTJ Dimensions

NPS O T H GROOVE # P E
1 150 38.1 83 R16 50.8 6.35
180 38.1 89 R20 68.27 6.35
2 215 38.1 102 R24 95.25 7.92
245 41.3 105 R27 107.95 7.92
3 265 47.7 117 R35 136.53 7.92
4 310 54 124 R39 161.93 7.92
6 395 82.6 171 R46 211.14 9.52
8 485 92.1 213 R50 269.88 11.13
10 585 108 254 R54 323.85 11.13
12 675 123.9 283 R58 381 14.27
14 750 133.4 298 R63 419.1 15.88
16 825 146.1 311 R67 469.9 17.48
18 915 162 327 R71 533.4 17.48
20 985 177.8 356 R75 584.2 17.48
24 1170 203.2 406 R79 692.15 20.62

 

NPS F R W X A Tg
1 8.74 0.8 25.4 52 33.5 6.4
8.74 0.8 25.4 70 48.3 6.4
2 11.91 0.8 27 105 60.3 6.4
11.91 0.8 27 124 73 6.4
3 11.91 0.8 27 133 88.9 9.5
4 11.91 0.8 27 162 114.3 12.7
6 13.49 1.5 28.6 229 168.3 12.7
8 16.66 1.5 33.3 292 219.1 12.7
10 16.66 1.5 33.3 368 273 12.7
12 23.01 1.5 39.7 451 323.8 12.7
14 26.97 2.4 44.4 495 355.6 12.7
16 30.18 2.4 50.8 552 406.4 12.7
18 30.18 2.4 50.8 597 457.2 12.7
20 33.32 2.4 54 641 508 12.7
24 36.53 2.4 58.7 762 609.6 12.7

 

CLASS 2500 WELD NECK ORIFICE RTJ

Orifice Flanges RTJ Dimensions

2500#   T H GROOVE # P E
1 160 38.1 92 R18 60.33 6.35
205 44.5 111 R23 82.55 7.92
2 235 50.8 127 R26 101.6 7.92
265 57.2 143 R28 111.13 9.53
3 305 66.7 168 R32 127 9.53
4 355 76.2 190 R38 157.18 11.13
6 485 108 273 R47 228.6 12.7
8 550 127 318 R51 279.4 14.27
10 675 165.1 419 R55 342.9 17.48
12 760 184.2 464 R60 406.4 17.48

 

2500# F R W X A Tg
1 8.74 0.8 25.4 57 33.5 6.4
11.91 0.8 27 79 48.3 6.4
2 11.91 0.8 27 95 60.3 6.4
13.49 1.5 30.2 114 73 6.4
3 13.49 1.5 30.2 133 88.9 9.5
4 16.66 1.5 33.3 165 114.3 12.7
6 19.84 1.5 36.5 235 168.3 12.7
8 23.01 1.5 39.7 305 219.1 12.7
10 30.18 2.4 47.6 375 273 12.7
12 33.32 2.4 50.8 441 323.8 12.7

 

 

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