DIMENSIONAL STANDARD
ASME B16.20
Spiral wound gasket dimensions. Select your pressure class, flange standard and units to find the matching dimensional table.
READING THE DRAWING
Four dimensions. One reference.
- D1
- Inner ring inside diameter
- D2
- Gasket inside diameter
- D3
- Gasket outside diameter
- D4
- Centering ring outside diameter
Find your dimensions
Select all three fields to display the table.
For Class 1500 and Class 2500, the supplied source provides ASME B16.5 dimensional data only.
Choose a pressure class, flange standard and unit system above.
| NPS | D1 Inner Ring ID |
D2 Gasket ID |
D3 Gasket OD |
D4 Centering Ring OD |
|---|---|---|---|---|
| 26 | 25.75 | 26.50 | 27.75 | 30.50 |
| 28 | 27.75 | 28.50 | 29.75 | 32.75 |
| 30 | 29.75 | 30.50 | 31.75 | 34.75 |
| 32 | 31.75 | 32.50 | 33.88 | 37.00 |
| 34 | 33.75 | 34.50 | 35.88 | 39.00 |
| 36 | 35.75 | 36.50 | 38.13 | 41.25 |
| 38 | 37.75 | 38.50 | 40.13 | 43.75 |
| 40 | 39.75 | 40.50 | 42.13 | 45.75 |
| 42 | 41.75 | 42.50 | 44.25 | 48.00 |
| 44 | 43.75 | 44.50 | 46.38 | 50.25 |
| 46 | 45.75 | 46.50 | 48.38 | 52.25 |
| 48 | 47.75 | 48.50 | 50.38 | 54.50 |
| 50 | 49.75 | 50.50 | 52.50 | 56.50 |
| 52 | 51.75 | 52.50 | 54.50 | 58.75 |
| 54 | 53.50 | 54.50 | 56.50 | 61.00 |
| 56 | 55.50 | 56.50 | 58.50 | 63.25 |
| 58 | 57.50 | 58.50 | 60.50 | 65.50 |
| 60 | 59.50 | 60.50 | 62.50 | 67.50 |
Engineering Notes — Inches
Class 150 U.S. customary values from the supplied ASME B16.20-2023 Series A source tables.
- D1 uses the inch values shown in parentheses in Table SW-2.1-5, Class 150.
- D2, D3 and D4 are taken directly from the Class 150 U.S. customary section of Table SW-2.1-2.
- These inch dimensions are source values; they are not calculated from the SI table.
- Only the Class 150 Series A values are presented on this page.
| NPS | D1 Inner Ring ID |
D2 Gasket ID |
D3 Gasket OD |
D4 Centering Ring OD |
|---|---|---|---|---|
| 26 | 654.1 | 673.1 | 704.9 | 774.7 |
| 28 | 704.9 | 723.9 | 755.7 | 831.9 |
| 30 | 755.7 | 774.7 | 806.5 | 882.7 |
| 32 | 806.5 | 825.5 | 860.6 | 939.8 |
| 34 | 857.3 | 876.3 | 911.4 | 990.6 |
| 36 | 908.1 | 927.1 | 968.5 | 1 047.8 |
| 38 | 958.9 | 977.9 | 1 019.3 | 1 111.3 |
| 40 | 1 009.7 | 1 028.7 | 1 070.1 | 1 162.1 |
| 42 | 1 060.5 | 1 079.5 | 1 124.0 | 1 219.2 |
| 44 | 1 111.3 | 1 130.3 | 1 178.1 | 1 276.4 |
| 46 | 1 162.1 | 1 181.1 | 1 228.9 | 1 327.2 |
| 48 | 1 212.9 | 1 231.9 | 1 279.7 | 1 384.3 |
| 50 | 1 263.7 | 1 282.7 | 1 333.5 | 1 435.1 |
| 52 | 1 314.5 | 1 333.5 | 1 384.3 | 1 492.3 |
| 54 | 1 358.9 | 1 384.3 | 1 435.1 | 1 549.4 |
| 56 | 1 409.7 | 1 435.1 | 1 485.9 | 1 606.6 |
| 58 | 1 460.5 | 1 485.9 | 1 536.7 | 1 663.7 |
| 60 | 1 511.3 | 1 536.7 | 1 587.5 | 1 714.5 |
Engineering Notes — Millimetres
Class 150 SI values from the supplied ASME B16.20-2023 Series A source tables.
- D1 is taken from Table SW-2.1-5, ASME B16.47 Series A, Class 150.
- D2, D3 and D4 are taken from Table SW-2.1-2, Class 150, SI Units.
- D2 represents gasket inside diameter, D3 gasket outside diameter and D4 centering-ring outside diameter.
- The data shown here contains only the Class 150 column set; Class 300, 400, 600 and 900 values are intentionally excluded from this page.
| NPS | D1 Inner Ring ID |
D2 Gasket ID |
D3 Gasket OD |
D4 Centering Ring OD |
|---|---|---|---|---|
| 26 | 25.75 | 26.50 | 27.50 | 28.56 |
| 28 | 27.75 | 28.50 | 29.50 | 30.56 |
| 30 | 29.75 | 30.50 | 31.50 | 32.56 |
| 32 | 31.75 | 32.50 | 33.50 | 34.69 |
| 34 | 33.75 | 34.50 | 35.75 | 36.81 |
| 36 | 35.75 | 36.50 | 37.75 | 38.88 |
| 38 | 37.75 | 38.38 | 39.75 | 41.13 |
| 40 | 39.75 | 40.25 | 41.88 | 43.13 |
| 42 | 41.75 | 42.50 | 43.88 | 45.13 |
| 44 | 43.75 | 44.25 | 45.88 | 47.13 |
| 46 | 45.75 | 46.50 | 48.19 | 49.44 |
| 48 | 47.75 | 48.50 | 50.00 | 51.44 |
| 50 | 49.75 | 50.50 | 52.19 | 53.44 |
| 52 | 51.75 | 52.50 | 54.19 | 55.44 |
| 54 | 53.75 | 54.50 | 56.00 | 57.63 |
| 56 | 56.00 | 56.88 | 58.19 | 59.63 |
| 58 | 58.19 | 59.06 | 60.19 | 62.19 |
| 60 | 60.44 | 61.31 | 62.44 | 64.19 |
Engineering Notes — Inches
Class 150 U.S. customary values from the supplied ASME B16.20-2023 Series B source tables.
- D1 uses the inch values shown in parentheses in Table SW-2.1-6, Class 150.
- D2, D3 and D4 are taken directly from Table SW-2.1-3, Class 150, U.S. Customary Units.
- These inch dimensions are source values and are not calculated from the millimetre values.
- Only the Class 150 Series B dimensional values are presented on this page.
| NPS | D1 Inner Ring ID |
D2 Gasket ID |
D3 Gasket OD |
D4 Centering Ring OD |
|---|---|---|---|---|
| 26 | 654.1 | 673.1 | 698.5 | 725.4 |
| 28 | 704.9 | 723.9 | 749.3 | 776.2 |
| 30 | 755.7 | 774.7 | 800.1 | 827.0 |
| 32 | 806.5 | 825.5 | 850.9 | 881.1 |
| 34 | 857.3 | 876.3 | 908.1 | 935.0 |
| 36 | 908.1 | 927.1 | 958.9 | 987.6 |
| 38 | 958.9 | 974.9 | 1 009.7 | 1 044.7 |
| 40 | 1 009.7 | 1 022.4 | 1 063.8 | 1 095.5 |
| 42 | 1 060.5 | 1 079.5 | 1 114.6 | 1 146.3 |
| 44 | 1 111.3 | 1 124.0 | 1 165.4 | 1 197.1 |
| 46 | 1 162.1 | 1 181.1 | 1 224.0 | 1 255.8 |
| 48 | 1 212.9 | 1 231.9 | 1 270.0 | 1 306.6 |
| 50 | 1 263.7 | 1 282.7 | 1 325.6 | 1 357.4 |
| 52 | 1 314.5 | 1 333.5 | 1 376.4 | 1 408.2 |
| 54 | 1 365.3 | 1 384.3 | 1 422.4 | 1 463.8 |
| 56 | 1 422.4 | 1 444.8 | 1 478.0 | 1 514.6 |
| 58 | 1 478.0 | 1 500.1 | 1 528.8 | 1 579.6 |
| 60 | 1 535.2 | 1 557.3 | 1 586.0 | 1 630.4 |
Engineering Notes — Millimetres
Class 150 SI values from the supplied ASME B16.20-2023 Series B source tables.
- D1 is taken from Table SW-2.1-6, ASME B16.47 Series B, Class 150.
- D2, D3 and D4 are taken from Table SW-2.1-3, Class 150, SI Units.
- D2 represents gasket inside diameter, D3 gasket outside diameter and D4 centering-ring outside diameter.
- Only the Class 150 values have been separated from the original multi-class table.
| NPS | D1 Inner Ring ID |
D2 Gasket ID |
D3 Gasket OD |
D4 Centering Ring OD |
|---|---|---|---|---|
| 1/2 | 0.56 | 0.75 | 1.25 | 1.88 |
| 3/4 | 0.81 | 1.00 | 1.56 | 2.25 |
| 1 | 1.06 | 1.25 | 1.88 | 2.63 |
| 1-1/4 | 1.50 | 1.88 | 2.38 | 3.00 |
| 1-1/2 | 1.75 | 2.13 | 2.75 | 3.38 |
| 2 | 2.19 | 2.75 | 3.38 | 4.13 |
| 2-1/2 | 2.62 | 3.25 | 3.88 | 4.88 |
| 3 | 3.19 | 4.00 | 4.75 | 5.38 |
| 3-1/2 | 3.98 | 4.50 | 5.25 | 6.38 |
| 4 | 4.19 | 5.00 | 5.88 | 6.88 |
| 5 | 5.19 | 6.13 | 7.00 | 7.75 |
| 6 | 6.19 | 7.19 | 8.25 | 8.75 |
| 8 | 8.50 | 9.19 | 10.38 | 11.00 |
| 10 | 10.56 | 11.31 | 12.50 | 13.38 |
| 12 | 12.50 | 13.38 | 14.75 | 16.13 |
| 14 | 13.75 | 14.63 | 16.00 | 17.75 |
| 16 | 15.75 | 16.63 | 18.25 | 20.25 |
| 18 | 17.69 | 18.69 | 20.75 | 21.63 |
| 20 | 19.69 | 20.69 | 22.75 | 23.88 |
| 22 | 22.38 | 23.38 | 24.63 | 26.00 |
| 24 | 23.75 | 24.75 | 27.00 | 28.25 |
Engineering Notes — Inches
Values shown above are the Class 150 U.S. customary values from the supplied ASME B16.20-2023 source tables.
- D1 uses the inch values shown in parentheses in Table SW-2.1-4, Class 150.
- D2 is taken from the Class 150 Inside Diameter of Gasket column in the U.S. customary continuation of Table SW-2.1-1.
- D3 is taken from the applicable Outside Diameter of Gasket column in Table SW-2.1-1.
- D4 is taken from the Class 150 Outside Diameter of Centering Ring column in Table SW-2.1-1.
- These inch values are source values and have not been generated by converting the millimetre table.
| NPS | D1 Inner Ring ID |
D2 Gasket ID |
D3 Gasket OD |
D4 Centering Ring OD |
|---|---|---|---|---|
| 1/2 | 14.2 | 19.1 | 31.8 | 47.8 |
| 3/4 | 20.6 | 25.4 | 39.6 | 57.2 |
| 1 | 26.9 | 31.8 | 47.8 | 66.8 |
| 1-1/4 | 38.1 | 47.8 | 60.5 | 76.2 |
| 1-1/2 | 44.5 | 54.1 | 69.9 | 85.9 |
| 2 | 55.6 | 69.9 | 85.9 | 104.9 |
| 2-1/2 | 66.5 | 82.6 | 98.6 | 124.0 |
| 3 | 81.0 | 101.6 | 120.7 | 136.7 |
| 3-1/2 | 101.1 | 114.3 | 133.4 | 161.9 |
| 4 | 106.4 | 127.0 | 149.4 | 174.8 |
| 5 | 131.8 | 155.7 | 177.8 | 196.9 |
| 6 | 157.2 | 182.6 | 209.6 | 222.3 |
| 8 | 215.9 | 233.4 | 263.7 | 279.4 |
| 10 | 268.2 | 287.3 | 317.5 | 339.9 |
| 12 | 317.5 | 339.9 | 374.7 | 409.7 |
| 14 | 349.3 | 371.6 | 406.4 | 450.9 |
| 16 | 400.1 | 422.4 | 463.6 | 514.4 |
| 18 | 449.3 | 474.7 | 527.1 | 549.4 |
| 20 | 500.1 | 525.5 | 577.9 | 606.6 |
| 22 | 568.4 | 593.8 | 625.5 | 660.4 |
| 24 | 603.3 | 628.7 | 685.8 | 717.6 |
Engineering Notes — Millimetres
Values shown above are the Class 150 SI values from the supplied ASME B16.20-2023 source tables.
- D1 is taken from Table SW-2.1-4, Class 150: Inside Diameter of Inner Ring.
- D2 is taken from Table SW-2.1-1, Class 150: Inside Diameter of Gasket.
- D3 is taken from Table SW-2.1-1: Outside Diameter of Gasket for Classes 150, 300, 400 and 600.
- D4 is taken from Table SW-2.1-1, Class 150: Outside Diameter of Centering Ring.
- Source-table note references are retained as source references; the complete note text was not included in the supplied screenshots.
| NPS |
D1 Inner Ring ID |
D2 Gasket ID |
D3 Gasket OD |
D4 Centering Ring OD |
|---|---|---|---|---|
| ½ | 0.56 | 0.75 | 1.25 | 2.50 |
| ¾ | 0.81 | 1.00 | 1.56 | 2.75 |
| 1 | 1.06 | 1.25 | 1.88 | 3.13 |
| 1¼ | 1.31 | 1.56 | 2.38 | 3.50 |
| 1½ | 1.63 | 1.88 | 2.75 | 3.88 |
| 2 | 2.06 | 2.31 | 3.38 | 5.63 |
| 2½ | 2.50 | 2.75 | 3.88 | 6.50 |
| 3 | 3.10 | 3.63 | 4.75 | 6.88 |
| 3½ | - | - | - | - |
| 4 | 3.85 | 4.63 | 5.88 | 8.25 |
| 5 | 4.90 | 5.63 | 7.00 | 10.00 |
| 6 | 5.80 | 6.75 | 8.25 | 11.13 |
| 8 | 7.75 | 8.50 | 10.13 | 13.88 |
| 10 | 9.69 | 10.50 | 12.25 | 17.13 |
| 12 | 11.50 | 12.75 | 14.50 | 20.50 |
| 14 | 12.63 | 14.25 | 15.75 | 22.75 |
| 16 | 14.50 | 16.00 | 18.00 | 25.25 |
| 18 | 16.75 | 18.25 | 20.50 | 27.75 |
| 20 | 18.75 | 20.25 | 22.50 | 29.75 |
| 22 | - | - | - | - |
| 24 | 22.75 | 24.25 | 26.75 | 35.50 |
Engineering Notes — Inches
Class 1500 U.S. customary dimensional values separated from the supplied ASME B16.20-2023 source tables.
- D1 uses the Class 1500 inch value associated with Table SW-2.1-4.
- D2, D3 and D4 are taken from the applicable U.S. customary Class 1500 data in Table SW-2.1-1.
- These inch dimensions are source values and have not been generated by converting the millimetre table.
- A dash (-) is shown wherever the supplied source contains a note reference instead of a dimensional value.
| NPS |
D1 Inner Ring ID |
D2 Gasket ID |
D3 Gasket OD |
D4 Centering Ring OD |
|---|---|---|---|---|
| ½ | 14.2 | 19.1 | 31.8 | 63.5 |
| ¾ | 20.6 | 25.4 | 39.6 | 69.9 |
| 1 | 26.9 | 31.8 | 47.8 | 79.5 |
| 1¼ | 33.3 | 39.6 | 60.5 | 88.9 |
| 1½ | 41.4 | 47.8 | 69.9 | 98.6 |
| 2 | 52.3 | 58.7 | 85.9 | 143.0 |
| 2½ | 63.5 | 69.9 | 98.6 | 165.1 |
| 3 | 78.7 | 92.2 | 120.7 | 174.8 |
| 3½ | - | - | - | - |
| 4 | 97.8 | 117.6 | 149.4 | 209.6 |
| 5 | 124.5 | 143.0 | 177.8 | 254.0 |
| 6 | 147.3 | 171.5 | 209.6 | 282.7 |
| 8 | 196.9 | 215.9 | 257.3 | 352.6 |
| 10 | 246.1 | 266.7 | 311.2 | 435.1 |
| 12 | 292.1 | 323.9 | 368.3 | 520.7 |
| 14 | 320.8 | 362.0 | 400.1 | 577.9 |
| 16 | 368.3 | 406.4 | 457.2 | 641.4 |
| 18 | 425.5 | 463.6 | 520.7 | 704.9 |
| 20 | 476.3 | 514.4 | 571.5 | 755.7 |
| 22 | - | - | - | - |
| 24 | 577.9 | 616.0 | 679.5 | 901.7 |
Engineering Notes — Millimetres
Class 1500 SI dimensional values separated from the supplied ASME B16.20-2023 source tables.
- D1 is taken from Table SW-2.1-4, Class 1500.
- D2, D3 and D4 are taken from the applicable Class 1500 data in Table SW-2.1-1.
- D2 is gasket inside diameter, D3 is gasket outside diameter and D4 is centering-ring outside diameter.
- A dash (-) is shown wherever the supplied source contains a note reference instead of a dimensional value.
| NPS |
D1 Inner Ring ID |
D2 Gasket ID |
D3 Gasket OD |
D4 Centering Ring OD |
|---|---|---|---|---|
| ½ | 0.56 | 0.75 | 1.25 | 2.75 |
| ¾ | 0.81 | 1.00 | 1.56 | 3.00 |
| 1 | 1.06 | 1.25 | 1.88 | 3.38 |
| 1¼ | 1.31 | 1.56 | 2.38 | 4.13 |
| 1½ | 1.63 | 1.88 | 2.75 | 4.63 |
| 2 | 2.06 | 2.31 | 3.38 | 5.75 |
| 2½ | 2.50 | 2.75 | 3.88 | 6.63 |
| 3 | 3.10 | 3.63 | 4.75 | 7.75 |
| 3½ | - | - | - | - |
| 4 | 3.85 | 4.63 | 5.88 | 9.25 |
| 5 | 4.90 | 5.63 | 7.00 | 11.00 |
| 6 | 5.80 | 6.75 | 8.25 | 12.50 |
| 8 | 7.75 | 8.50 | 10.13 | 15.25 |
| 10 | 9.69 | 10.63 | 12.25 | 18.75 |
| 12 | 11.50 | 12.50 | 14.50 | 21.63 |
| 14 | - | - | 15.75 | - |
| 16 | - | - | 18.00 | - |
| 18 | - | - | 20.50 | - |
| 20 | - | - | 22.50 | - |
| 22 | - | - | - | - |
| 24 | - | - | 26.75 | - |
Engineering Notes — Inches
Class 2500 U.S. customary dimensional values separated from the supplied ASME B16.20-2023 source tables.
- D1 uses the Class 2500 inch value associated with Table SW-2.1-4.
- D2, D3 and D4 are taken from the applicable U.S. customary Class 2500 data in Table SW-2.1-1.
- These inch dimensions are source values and have not been generated by converting the millimetre table.
- A dash (-) is shown wherever the supplied source contains a note reference instead of a dimensional value.
| NPS |
D1 Inner Ring ID |
D2 Gasket ID |
D3 Gasket OD |
D4 Centering Ring OD |
|---|---|---|---|---|
| ½ | 14.2 | 19.1 | 31.8 | 69.9 |
| ¾ | 20.6 | 25.4 | 39.6 | 76.2 |
| 1 | 26.9 | 31.8 | 47.8 | 85.9 |
| 1¼ | 33.3 | 39.6 | 60.5 | 104.9 |
| 1½ | 41.4 | 47.8 | 69.9 | 117.6 |
| 2 | 52.3 | 58.7 | 85.9 | 146.1 |
| 2½ | 63.5 | 69.9 | 98.6 | 168.4 |
| 3 | 78.7 | 92.2 | 120.7 | 196.9 |
| 3½ | - | - | - | - |
| 4 | 97.8 | 117.6 | 149.4 | 235.0 |
| 5 | 124.5 | 143.0 | 177.8 | 279.4 |
| 6 | 147.3 | 171.5 | 209.6 | 317.5 |
| 8 | 196.9 | 215.9 | 257.3 | 387.4 |
| 10 | 246.1 | 270.0 | 311.2 | 476.3 |
| 12 | 292.1 | 317.5 | 368.3 | 549.4 |
| 14 | - | - | 400.1 | - |
| 16 | - | - | 457.2 | - |
| 18 | - | - | 520.7 | - |
| 20 | - | - | 571.5 | - |
| 22 | - | - | - | - |
| 24 | - | - | 679.5 | - |
Engineering Notes — Millimetres
Class 2500 SI dimensional values separated from the supplied ASME B16.20-2023 source tables.
- D1 is taken from Table SW-2.1-4, Class 2500.
- D2, D3 and D4 are taken from the applicable Class 2500 data in Table SW-2.1-1.
- D2 is gasket inside diameter, D3 is gasket outside diameter and D4 is centering-ring outside diameter.
- A dash (-) is shown wherever the supplied source contains a note reference instead of a dimensional value.
| NPS | D1 Inner Ring ID |
D2 Gasket ID |
D3 Gasket OD |
D4 Centering Ring OD |
|---|---|---|---|---|
| 26 | 25.75 | 27.00 | 29.00 | 32.88 |
| 28 | 27.75 | 29.00 | 31.00 | 35.38 |
| 30 | 29.75 | 31.25 | 33.25 | 37.50 |
| 32 | 31.75 | 33.50 | 35.50 | 39.63 |
| 34 | 33.75 | 35.50 | 37.50 | 41.63 |
| 36 | 35.75 | 37.63 | 39.63 | 44.00 |
| 38 | 37.50 | 38.50 | 40.00 | 41.50 |
| 40 | 39.50 | 40.25 | 42.13 | 43.88 |
| 42 | 41.50 | 42.25 | 44.13 | 45.88 |
| 44 | 43.50 | 44.50 | 46.50 | 48.00 |
| 46 | 45.38 | 46.38 | 48.38 | 50.13 |
| 48 | 47.63 | 48.63 | 50.63 | 52.13 |
| 50 | 49.00 | 51.00 | 53.00 | 54.25 |
| 52 | 52.00 | 53.00 | 55.00 | 56.25 |
| 54 | 53.25 | 55.25 | 57.25 | 58.75 |
| 56 | 55.25 | 57.25 | 59.25 | 60.75 |
| 58 | 57.00 | 59.50 | 61.50 | 62.75 |
| 60 | 60.00 | 61.50 | 63.50 | 64.75 |
Engineering Notes — Inches
Class 300 U.S. customary dimensional data bifurcated from the supplied Series A source tables.
- D1 uses the Class 300 inch values supplied in Table SW-2.1-5.
- D2, D3 and D4 are the Class 300 values from the U.S. customary portion of Table SW-2.1-2.
- The inch dimensions are source values rather than conversions generated from the SI values.
- Only Class 300 Series A data is shown.
| NPS | D1 Inner Ring ID |
D2 Gasket ID |
D3 Gasket OD |
D4 Centering Ring OD |
|---|---|---|---|---|
| 26 | 654.1 | 685.8 | 736.6 | 835.2 |
| 28 | 704.9 | 736.6 | 787.4 | 898.7 |
| 30 | 755.7 | 793.8 | 844.6 | 952.5 |
| 32 | 806.5 | 850.9 | 901.7 | 1 006.6 |
| 34 | 857.3 | 901.7 | 952.5 | 1 057.4 |
| 36 | 908.1 | 955.8 | 1 006.6 | 1 117.6 |
| 38 | 952.5 | 977.9 | 1 016.0 | 1 054.1 |
| 40 | 1 003.3 | 1 022.4 | 1 070.1 | 1 114.6 |
| 42 | 1 054.1 | 1 073.2 | 1 120.9 | 1 165.4 |
| 44 | 1 104.9 | 1 130.3 | 1 181.1 | 1 219.2 |
| 46 | 1 152.7 | 1 178.1 | 1 228.9 | 1 273.3 |
| 48 | 1 209.8 | 1 235.2 | 1 286.0 | 1 324.1 |
| 50 | 1 244.6 | 1 295.4 | 1 346.2 | 1 378.0 |
| 52 | 1 320.8 | 1 346.2 | 1 397.0 | 1 428.8 |
| 54 | 1 352.6 | 1 403.4 | 1 454.2 | 1 492.3 |
| 56 | 1 403.4 | 1 454.2 | 1 505.0 | 1 543.1 |
| 58 | 1 447.8 | 1 511.3 | 1 562.1 | 1 593.9 |
| 60 | 1 524.0 | 1 562.1 | 1 612.9 | 1 644.7 |
Engineering Notes — Millimetres
Class 300 SI dimensional data bifurcated from the supplied ASME B16.20-2023 Series A tables.
- D1 is taken from Table SW-2.1-5, Class 300.
- D2, D3 and D4 are taken from the Class 300 column group of Table SW-2.1-2.
- D2 is gasket inside diameter, D3 is gasket outside diameter and D4 is centering-ring outside diameter.
- Class 150, 400, 600 and 900 values have been excluded from this Class 300 page.
| NPS | D1 Inner Ring ID |
D2 Gasket ID |
D3 Gasket OD |
D4 Centering Ring OD |
|---|---|---|---|---|
| 26 | 25.75 | 26.50 | 28.00 | 30.38 |
| 28 | 27.75 | 28.50 | 30.00 | 32.50 |
| 30 | 29.75 | 30.50 | 32.00 | 34.88 |
| 32 | 31.75 | 32.50 | 34.00 | 37.00 |
| 34 | 33.75 | 34.50 | 36.00 | 39.13 |
| 36 | 35.75 | 36.50 | 38.00 | 41.25 |
| 38 | 38.25 | 39.75 | 41.25 | 43.25 |
| 40 | 40.25 | 41.75 | 43.25 | 45.25 |
| 42 | 42.75 | 43.75 | 45.25 | 47.25 |
| 44 | 44.25 | 45.75 | 47.25 | 49.25 |
| 46 | 46.38 | 47.88 | 49.38 | 51.88 |
| 48 | 48.50 | 49.75 | 51.63 | 53.88 |
| 50 | 49.88 | 51.88 | 53.38 | 55.88 |
| 52 | 51.88 | 53.88 | 55.38 | 57.88 |
| 54 | 53.75 | 55.25 | 57.25 | 60.25 |
| 56 | 56.25 | 58.25 | 60.00 | 62.75 |
| 58 | 58.44 | 60.44 | 61.94 | 65.19 |
| 60 | 61.31 | 62.56 | 64.19 | 67.19 |
Engineering Notes — Inches
Class 300 U.S. customary dimensional data bifurcated from the supplied Series B source tables.
- D1 uses the Class 300 inch values from Table SW-2.1-6.
- D2, D3 and D4 are taken from the Class 300 U.S. customary group in Table SW-2.1-3.
- These inch dimensions are source values; they are not converted from the SI table.
- Only Class 300 Series B values are shown.
| NPS | D1 Inner Ring ID |
D2 Gasket ID |
D3 Gasket OD |
D4 Centering Ring OD |
|---|---|---|---|---|
| 26 | 654.1 | 673.1 | 711.2 | 771.7 |
| 28 | 704.9 | 723.9 | 762.0 | 825.5 |
| 30 | 755.7 | 774.7 | 812.8 | 886.0 |
| 32 | 806.5 | 825.5 | 863.6 | 939.8 |
| 34 | 857.3 | 876.3 | 914.4 | 993.9 |
| 36 | 908.1 | 927.1 | 965.2 | 1 047.8 |
| 38 | 971.6 | 1 009.7 | 1 047.8 | 1 098.6 |
| 40 | 1 022.4 | 1 060.5 | 1 098.6 | 1 149.4 |
| 42 | 1 085.9 | 1 111.3 | 1 149.4 | 1 200.2 |
| 44 | 1 124.0 | 1 162.1 | 1 200.2 | 1 251.0 |
| 46 | 1 178.1 | 1 216.2 | 1 254.3 | 1 317.8 |
| 48 | 1 231.9 | 1 263.7 | 1 311.4 | 1 368.6 |
| 50 | 1 267.0 | 1 317.8 | 1 355.9 | 1 419.4 |
| 52 | 1 317.8 | 1 368.6 | 1 406.7 | 1 470.2 |
| 54 | 1 365.3 | 1 403.4 | 1 454.2 | 1 530.4 |
| 56 | 1 428.8 | 1 479.6 | 1 524.0 | 1 593.9 |
| 58 | 1 484.4 | 1 535.2 | 1 573.3 | 1 655.8 |
| 60 | 1 557.3 | 1 589.0 | 1 630.4 | 1 706.6 |
Engineering Notes — Millimetres
Class 300 SI dimensional data bifurcated from the supplied ASME B16.20-2023 Series B tables.
- D1 is taken from Table SW-2.1-6, Class 300.
- D2, D3 and D4 are taken from the Class 300 group in Table SW-2.1-3.
- D2 is gasket inside diameter, D3 is gasket outside diameter and D4 is centering-ring outside diameter.
- Only Class 300 data is presented here; other pressure-class columns are omitted.
| NPS | D1 Inner Ring ID |
D2 Gasket ID |
D3 Gasket OD |
D4 Centering Ring OD |
|---|---|---|---|---|
| 26 | 25.75 | 26.50 | 27.50 | 28.56 |
| 28 | 27.75 | 28.50 | 29.50 | 30.56 |
| 30 | 29.75 | 30.50 | 31.50 | 32.56 |
| 32 | 31.75 | 32.50 | 33.50 | 34.69 |
| 34 | 33.75 | 34.50 | 35.75 | 36.81 |
| 36 | 35.75 | 36.50 | 37.75 | 38.88 |
| 38 | 37.75 | 38.38 | 39.75 | 41.13 |
| 40 | 39.75 | 40.25 | 41.88 | 43.13 |
| 42 | 41.75 | 42.50 | 43.88 | 45.13 |
| 44 | 43.75 | 44.25 | 45.88 | 47.13 |
| 46 | 45.75 | 46.50 | 48.19 | 49.44 |
| 48 | 47.75 | 48.50 | 50.00 | 51.44 |
| 50 | 49.75 | 50.50 | 52.19 | 53.44 |
| 52 | 51.75 | 52.50 | 54.19 | 55.44 |
| 54 | 53.75 | 54.50 | 56.00 | 57.63 |
| 56 | 56.00 | 56.88 | 58.19 | 59.63 |
| 58 | 58.19 | 59.06 | 60.19 | 62.19 |
| 60 | 60.44 | 61.31 | 62.44 | 64.19 |
Engineering Notes — Inches
Class 150 U.S. customary values from the supplied ASME B16.20-2023 Series B source tables.
- D1 uses the inch values shown in parentheses in Table SW-2.1-6, Class 150.
- D2, D3 and D4 are taken directly from Table SW-2.1-3, Class 150, U.S. Customary Units.
- These inch dimensions are source values and are not calculated from the millimetre values.
- Only the Class 150 Series B dimensional values are presented on this page.
| NPS | D1 Inner Ring ID |
D2 Gasket ID |
D3 Gasket OD |
D4 Centering Ring OD |
|---|---|---|---|---|
| 26 | 654.1 | 673.1 | 698.5 | 725.4 |
| 28 | 704.9 | 723.9 | 749.3 | 776.2 |
| 30 | 755.7 | 774.7 | 800.1 | 827.0 |
| 32 | 806.5 | 825.5 | 850.9 | 881.1 |
| 34 | 857.3 | 876.3 | 908.1 | 935.0 |
| 36 | 908.1 | 927.1 | 958.9 | 987.6 |
| 38 | 958.9 | 974.9 | 1 009.7 | 1 044.7 |
| 40 | 1 009.7 | 1 022.4 | 1 063.8 | 1 095.5 |
| 42 | 1 060.5 | 1 079.5 | 1 114.6 | 1 146.3 |
| 44 | 1 111.3 | 1 124.0 | 1 165.4 | 1 197.1 |
| 46 | 1 162.1 | 1 181.1 | 1 224.0 | 1 255.8 |
| 48 | 1 212.9 | 1 231.9 | 1 270.0 | 1 306.6 |
| 50 | 1 263.7 | 1 282.7 | 1 325.6 | 1 357.4 |
| 52 | 1 314.5 | 1 333.5 | 1 376.4 | 1 408.2 |
| 54 | 1 365.3 | 1 384.3 | 1 422.4 | 1 463.8 |
| 56 | 1 422.4 | 1 444.8 | 1 478.0 | 1 514.6 |
| 58 | 1 478.0 | 1 500.1 | 1 528.8 | 1 579.6 |
| 60 | 1 535.2 | 1 557.3 | 1 586.0 | 1 630.4 |
Engineering Notes — Millimetres
Class 150 SI values from the supplied ASME B16.20-2023 Series B source tables.
- D1 is taken from Table SW-2.1-6, ASME B16.47 Series B, Class 150.
- D2, D3 and D4 are taken from Table SW-2.1-3, Class 150, SI Units.
- D2 represents gasket inside diameter, D3 gasket outside diameter and D4 centering-ring outside diameter.
- Only the Class 150 values have been separated from the original multi-class table.
| NPS |
D1 Inner Ring ID |
D2 Gasket ID |
D3 Gasket OD |
D4 Centering Ring OD |
|---|---|---|---|---|
| 26 | 26.00 | 27.00 | 29.00 | 32.75 |
| 28 | 28.00 | 29.00 | 31.00 | 35.13 |
| 30 | 29.75 | 31.25 | 33.25 | 37.25 |
| 32 | 32.00 | 33.50 | 35.50 | 39.50 |
| 34 | 34.00 | 35.50 | 37.50 | 41.50 |
| 36 | 36.13 | 37.63 | 39.63 | 44.00 |
| 38 | 37.50 | 38.25 | 40.25 | 42.25 |
| 40 | 39.38 | 40.38 | 42.38 | 44.38 |
| 42 | 41.38 | 42.38 | 44.38 | 46.38 |
| 44 | 43.50 | 44.50 | 46.50 | 48.50 |
| 46 | 46.00 | 47.00 | 49.00 | 50.75 |
| 48 | 47.50 | 49.00 | 51.00 | 53.00 |
| 50 | 49.50 | 51.00 | 53.00 | 55.25 |
| 52 | 51.50 | 53.00 | 55.00 | 57.25 |
| 54 | 53.25 | 55.25 | 57.25 | 59.75 |
| 56 | 55.25 | 57.25 | 59.25 | 61.75 |
| 58 | 57.25 | 59.25 | 61.25 | 63.75 |
| 60 | 59.75 | 61.75 | 63.75 | 66.25 |
Engineering Notes — Inches
Class 400 U.S. customary dimensional values separated from the supplied ASME B16.20-2023 source tables.
- D1 uses the Class 400 inch value associated with Table SW-2.1-5.
- D2, D3 and D4 are taken from the applicable U.S. customary Class 400 data in Table SW-2.1-2.
- These inch dimensions are source values and have not been generated by converting the millimetre table.
- A dash (-) is shown wherever the supplied source contains a note reference instead of a dimensional value.
| NPS |
D1 Inner Ring ID |
D2 Gasket ID |
D3 Gasket OD |
D4 Centering Ring OD |
|---|---|---|---|---|
| 26 | 660.4 | 685.8 | 736.6 | 831.9 |
| 28 | 711.2 | 736.6 | 787.4 | 892.3 |
| 30 | 755.7 | 793.8 | 844.6 | 946.2 |
| 32 | 812.8 | 850.9 | 901.7 | 1 003.3 |
| 34 | 863.6 | 901.7 | 952.5 | 1 054.1 |
| 36 | 917.7 | 955.8 | 1 006.6 | 1 117.6 |
| 38 | 952.5 | 971.6 | 1 022.4 | 1 073.2 |
| 40 | 1 000.3 | 1 025.7 | 1 076.5 | 1 127.3 |
| 42 | 1 051.1 | 1 076.5 | 1 127.3 | 1 178.1 |
| 44 | 1 104.9 | 1 130.3 | 1 181.1 | 1 231.9 |
| 46 | 1 168.4 | 1 193.8 | 1 244.6 | 1 289.1 |
| 48 | 1 206.5 | 1 244.6 | 1 295.4 | 1 346.2 |
| 50 | 1 257.3 | 1 295.4 | 1 346.2 | 1 403.4 |
| 52 | 1 308.1 | 1 346.2 | 1 397.0 | 1 454.2 |
| 54 | 1 352.6 | 1 403.4 | 1 454.2 | 1 517.7 |
| 56 | 1 403.4 | 1 454.2 | 1 505.0 | 1 568.5 |
| 58 | 1 454.2 | 1 505.0 | 1 555.8 | 1 619.3 |
| 60 | 1 517.7 | 1 568.5 | 1 619.3 | 1 682.8 |
Engineering Notes — Millimetres
Class 400 SI dimensional values separated from the supplied ASME B16.20-2023 source tables.
- D1 is taken from Table SW-2.1-5, Class 400.
- D2, D3 and D4 are taken from the applicable Class 400 data in Table SW-2.1-2.
- D2 is gasket inside diameter, D3 is gasket outside diameter and D4 is centering-ring outside diameter.
- A dash (-) is shown wherever the supplied source contains a note reference instead of a dimensional value.
| NPS |
D1 Inner Ring ID |
D2 Gasket ID |
D3 Gasket OD |
D4 Centering Ring OD |
|---|---|---|---|---|
| 26 | 25.75 | 26.25 | 27.50 | 29.38 |
| 28 | 27.63 | 28.13 | 29.50 | 31.50 |
| 30 | 29.63 | 30.13 | 31.75 | 33.75 |
| 32 | 31.50 | 32.00 | 33.88 | 35.88 |
| 34 | 33.50 | 34.13 | 35.88 | 37.88 |
| 36 | 35.38 | 36.13 | 38.00 | 40.25 |
| 38 | 37.50 | 38.25 | 40.25 | 42.25 |
| 40 | 39.38 | 40.38 | 42.38 | 44.38 |
| 42 | 41.38 | 42.38 | 44.38 | 46.38 |
| 44 | 43.50 | 44.50 | 46.50 | 48.50 |
| 46 | 46.00 | 47.00 | 49.00 | 50.75 |
| 48 | 47.50 | 49.00 | 51.00 | 53.00 |
| 50 | 49.50 | 51.00 | 53.00 | 55.25 |
| 52 | 51.50 | 53.00 | 55.00 | 57.25 |
| 54 | 53.25 | 55.25 | 57.25 | 59.75 |
| 56 | 55.25 | 57.25 | 59.25 | 61.75 |
| 58 | 57.25 | 59.25 | 61.25 | 63.75 |
| 60 | 59.75 | 61.75 | 63.75 | 66.25 |
Engineering Notes — Inches
Class 400 U.S. customary dimensional values separated from the supplied ASME B16.20-2023 source tables.
- D1 uses the Class 400 inch value associated with Table SW-2.1-6.
- D2, D3 and D4 are taken from the applicable U.S. customary Class 400 data in Table SW-2.1-3.
- These inch dimensions are source values and have not been generated by converting the millimetre table.
- A dash (-) is shown wherever the supplied source contains a note reference instead of a dimensional value.
| NPS |
D1 Inner Ring ID |
D2 Gasket ID |
D3 Gasket OD |
D4 Centering Ring OD |
|---|---|---|---|---|
| 26 | 654.1 | 666.8 | 698.5 | 746.3 |
| 28 | 701.8 | 714.5 | 749.3 | 800.1 |
| 30 | 752.6 | 765.3 | 806.5 | 857.3 |
| 32 | 800.1 | 812.8 | 860.6 | 911.4 |
| 34 | 850.9 | 866.9 | 911.4 | 962.2 |
| 36 | 898.7 | 917.7 | 965.2 | 1 022.4 |
| 38 | 952.5 | 971.6 | 1 022.4 | 1 073.2 |
| 40 | 1 000.3 | 1 025.7 | 1 076.5 | 1 127.3 |
| 42 | 1 051.1 | 1 076.5 | 1 127.3 | 1 178.1 |
| 44 | 1 104.9 | 1 130.3 | 1 181.1 | 1 231.9 |
| 46 | 1 168.4 | 1 193.8 | 1 244.6 | 1 289.1 |
| 48 | 1 206.5 | 1 244.6 | 1 295.4 | 1 346.2 |
| 50 | 1 257.3 | 1 295.4 | 1 346.2 | 1 403.4 |
| 52 | 1 308.1 | 1 346.2 | 1 397.0 | 1 454.2 |
| 54 | 1 352.6 | 1 403.4 | 1 454.2 | 1 517.7 |
| 56 | 1 403.4 | 1 454.2 | 1 505.0 | 1 568.5 |
| 58 | 1 454.2 | 1 505.0 | 1 555.8 | 1 619.3 |
| 60 | 1 517.7 | 1 568.5 | 1 619.3 | 1 682.8 |
Engineering Notes — Millimetres
Class 400 SI dimensional values separated from the supplied ASME B16.20-2023 source tables.
- D1 is taken from Table SW-2.1-6, Class 400.
- D2, D3 and D4 are taken from the applicable Class 400 data in Table SW-2.1-3.
- D2 is gasket inside diameter, D3 is gasket outside diameter and D4 is centering-ring outside diameter.
- A dash (-) is shown wherever the supplied source contains a note reference instead of a dimensional value.
| NPS |
D1 Inner Ring ID |
D2 Gasket ID |
D3 Gasket OD |
D4 Centering Ring OD |
|---|---|---|---|---|
| ½ | - | - | 1.25 | - |
| ¾ | - | - | 1.56 | - |
| 1 | - | - | 1.88 | - |
| 1¼ | - | - | 2.38 | - |
| 1½ | - | - | 2.75 | - |
| 2 | - | - | 3.38 | - |
| 2½ | - | - | 3.88 | - |
| 3 | - | - | 4.75 | - |
| 3½ | - | - | 5.25 | - |
| 4 | 4.04 | 4.75 | 5.88 | 7.00 |
| 5 | 5.05 | 5.81 | 7.00 | 8.38 |
| 6 | 6.10 | 6.88 | 8.25 | 9.75 |
| 8 | 8.10 | 8.88 | 10.38 | 12.00 |
| 10 | 10.05 | 10.81 | 12.50 | 14.13 |
| 12 | 12.10 | 12.88 | 14.75 | 16.50 |
| 14 | 13.50 | 14.25 | 16.00 | 19.00 |
| 16 | 15.35 | 16.25 | 18.25 | 21.13 |
| 18 | 17.25 | 18.50 | 20.75 | 23.38 |
| 20 | 19.25 | 20.50 | 22.75 | 25.50 |
| 22 | 21.50 | 22.75 | 24.63 | 27.63 |
| 24 | 23.25 | 24.75 | 27.00 | 30.25 |
Engineering Notes — Inches
Class 400 U.S. customary dimensional values separated from the supplied ASME B16.20-2023 source tables.
- D1 uses the Class 400 inch value associated with Table SW-2.1-4.
- D2, D3 and D4 are taken from the applicable U.S. customary Class 400 data in Table SW-2.1-1.
- These inch dimensions are source values and have not been generated by converting the millimetre table.
- A dash (-) is shown wherever the supplied source contains a note reference instead of a dimensional value.
| NPS |
D1 Inner Ring ID |
D2 Gasket ID |
D3 Gasket OD |
D4 Centering Ring OD |
|---|---|---|---|---|
| ½ | - | - | 31.8 | - |
| ¾ | - | - | 39.6 | - |
| 1 | - | - | 47.8 | - |
| 1¼ | - | - | 60.5 | - |
| 1½ | - | - | 69.9 | - |
| 2 | - | - | 85.9 | - |
| 2½ | - | - | 98.6 | - |
| 3 | - | - | 120.7 | - |
| 3½ | - | - | 133.4 | - |
| 4 | 102.6 | 120.7 | 149.4 | 177.8 |
| 5 | 128.3 | 147.6 | 177.8 | 212.9 |
| 6 | 154.9 | 174.8 | 209.6 | 247.7 |
| 8 | 205.7 | 225.6 | 263.7 | 304.8 |
| 10 | 255.3 | 274.6 | 317.5 | 358.9 |
| 12 | 307.3 | 327.2 | 374.7 | 419.1 |
| 14 | 342.9 | 362.0 | 406.4 | 482.6 |
| 16 | 389.9 | 412.8 | 463.6 | 536.7 |
| 18 | 438.2 | 469.9 | 527.1 | 593.9 |
| 20 | 489.0 | 520.7 | 577.9 | 647.7 |
| 22 | 546.2 | 577.9 | 625.5 | 701.8 |
| 24 | 590.6 | 628.7 | 685.8 | 768.4 |
Engineering Notes — Millimetres
Class 400 SI dimensional values separated from the supplied ASME B16.20-2023 source tables.
- D1 is taken from Table SW-2.1-4, Class 400.
- D2, D3 and D4 are taken from the applicable Class 400 data in Table SW-2.1-1.
- D2 is gasket inside diameter, D3 is gasket outside diameter and D4 is centering-ring outside diameter.
- A dash (-) is shown wherever the supplied source contains a note reference instead of a dimensional value.
| NPS |
D1 Inner Ring ID |
D2 Gasket ID |
D3 Gasket OD |
D4 Centering Ring OD |
|---|---|---|---|---|
| 26 | 25.50 | 27.00 | 29.00 | 34.13 |
| 28 | 27.50 | 29.00 | 31.00 | 36.00 |
| 30 | 29.75 | 31.25 | 33.25 | 38.25 |
| 32 | 32.00 | 33.50 | 35.50 | 40.25 |
| 34 | 34.00 | 35.50 | 37.50 | 42.25 |
| 36 | 36.13 | 37.63 | 39.63 | 44.50 |
| 38 | 37.50 | 39.00 | 41.00 | 43.50 |
| 40 | 39.75 | 41.25 | 43.25 | 45.50 |
| 42 | 42.00 | 43.50 | 45.50 | 48.00 |
| 44 | 43.75 | 45.75 | 47.75 | 50.00 |
| 46 | 45.75 | 47.75 | 49.75 | 52.25 |
| 48 | 48.00 | 50.00 | 52.00 | 54.75 |
| 50 | 50.00 | 52.00 | 54.00 | 57.00 |
| 52 | 52.00 | 54.00 | 56.00 | 59.00 |
| 54 | 54.25 | 56.25 | 58.25 | 61.25 |
| 56 | 56.25 | 58.25 | 60.25 | 63.50 |
| 58 | 58.00 | 60.50 | 62.50 | 65.50 |
| 60 | 60.25 | 62.75 | 64.75 | 68.25 |
Engineering Notes — Inches
Class 600 U.S. customary dimensional values separated from the supplied ASME B16.20-2023 source tables.
- D1 uses the Class 600 inch value associated with Table SW-2.1-5.
- D2, D3 and D4 are taken from the applicable U.S. customary Class 600 data in Table SW-2.1-2.
- These inch dimensions are source values and have not been generated by converting the millimetre table.
- A dash (-) is shown wherever the supplied source contains a note reference instead of a dimensional value.
| NPS |
D1 Inner Ring ID |
D2 Gasket ID |
D3 Gasket OD |
D4 Centering Ring OD |
|---|---|---|---|---|
| 26 | 647.7 | 685.8 | 736.6 | 866.9 |
| 28 | 698.5 | 736.6 | 787.4 | 914.4 |
| 30 | 755.7 | 793.8 | 844.6 | 971.6 |
| 32 | 812.8 | 850.9 | 901.7 | 1 022.4 |
| 34 | 863.6 | 901.7 | 952.5 | 1 073.2 |
| 36 | 917.7 | 955.8 | 1 006.6 | 1 130.3 |
| 38 | 952.5 | 990.6 | 1 041.4 | 1 104.9 |
| 40 | 1 009.7 | 1 047.8 | 1 098.6 | 1 155.7 |
| 42 | 1 066.8 | 1 104.9 | 1 155.7 | 1 219.2 |
| 44 | 1 111.3 | 1 162.1 | 1 212.9 | 1 270.0 |
| 46 | 1 162.1 | 1 212.9 | 1 263.7 | 1 327.2 |
| 48 | 1 219.2 | 1 270.0 | 1 320.8 | 1 390.7 |
| 50 | 1 270.0 | 1 320.8 | 1 371.6 | 1 447.8 |
| 52 | 1 320.8 | 1 371.6 | 1 422.4 | 1 498.6 |
| 54 | 1 378.0 | 1 428.8 | 1 479.6 | 1 555.8 |
| 56 | 1 428.8 | 1 479.6 | 1 530.4 | 1 612.9 |
| 58 | 1 473.2 | 1 536.7 | 1 587.5 | 1 663.7 |
| 60 | 1 530.4 | 1 593.9 | 1 644.7 | 1 733.6 |
Engineering Notes — Millimetres
Class 600 SI dimensional values separated from the supplied ASME B16.20-2023 source tables.
- D1 is taken from Table SW-2.1-5, Class 600.
- D2, D3 and D4 are taken from the applicable Class 600 data in Table SW-2.1-2.
- D2 is gasket inside diameter, D3 is gasket outside diameter and D4 is centering-ring outside diameter.
- A dash (-) is shown wherever the supplied source contains a note reference instead of a dimensional value.
| NPS |
D1 Inner Ring ID |
D2 Gasket ID |
D3 Gasket OD |
D4 Centering Ring OD |
|---|---|---|---|---|
| 26 | 25.38 | 26.13 | 28.13 | 30.13 |
| 28 | 27.00 | 27.75 | 29.75 | 32.25 |
| 30 | 29.63 | 30.63 | 32.63 | 34.63 |
| 32 | 31.25 | 32.75 | 34.75 | 36.75 |
| 34 | 33.50 | 35.00 | 37.00 | 39.25 |
| 36 | 35.50 | 37.00 | 39.00 | 41.25 |
| 38 | 37.50 | 39.00 | 41.00 | 43.50 |
| 40 | 39.75 | 41.25 | 43.25 | 45.50 |
| 42 | 42.00 | 43.50 | 45.50 | 48.00 |
| 44 | 43.75 | 45.75 | 47.75 | 50.00 |
| 46 | 45.75 | 47.75 | 49.75 | 52.25 |
| 48 | 48.00 | 50.00 | 52.00 | 54.75 |
| 50 | 50.00 | 52.00 | 54.00 | 57.00 |
| 52 | 52.00 | 54.00 | 56.00 | 59.00 |
| 54 | 54.25 | 56.25 | 58.25 | 61.25 |
| 56 | 56.25 | 58.25 | 60.25 | 63.50 |
| 58 | 58.00 | 60.50 | 62.50 | 65.50 |
| 60 | 60.25 | 62.75 | 64.75 | 68.25 |
Engineering Notes — Inches
Class 600 U.S. customary dimensional values separated from the supplied ASME B16.20-2023 source tables.
- D1 uses the Class 600 inch value associated with Table SW-2.1-6.
- D2, D3 and D4 are taken from the applicable U.S. customary Class 600 data in Table SW-2.1-3.
- These inch dimensions are source values and have not been generated by converting the millimetre table.
- A dash (-) is shown wherever the supplied source contains a note reference instead of a dimensional value.
| NPS |
D1 Inner Ring ID |
D2 Gasket ID |
D3 Gasket OD |
D4 Centering Ring OD |
|---|---|---|---|---|
| 26 | 644.7 | 663.7 | 714.5 | 765.3 |
| 28 | 685.8 | 704.9 | 755.7 | 819.2 |
| 30 | 752.6 | 778.0 | 828.8 | 879.6 |
| 32 | 793.8 | 831.9 | 882.7 | 933.5 |
| 34 | 850.9 | 889.0 | 939.8 | 997.0 |
| 36 | 901.7 | 939.8 | 990.6 | 1 047.8 |
| 38 | 952.5 | 990.6 | 1 041.4 | 1 104.9 |
| 40 | 1 009.7 | 1 047.8 | 1 098.6 | 1 155.7 |
| 42 | 1 066.8 | 1 104.9 | 1 155.7 | 1 219.2 |
| 44 | 1 111.3 | 1 162.1 | 1 212.9 | 1 270.0 |
| 46 | 1 162.1 | 1 212.9 | 1 263.7 | 1 327.2 |
| 48 | 1 219.2 | 1 270.0 | 1 320.8 | 1 390.7 |
| 50 | 1 270.0 | 1 320.8 | 1 371.6 | 1 447.8 |
| 52 | 1 320.8 | 1 371.6 | 1 422.4 | 1 498.6 |
| 54 | 1 378.0 | 1 428.8 | 1 479.6 | 1 555.8 |
| 56 | 1 428.8 | 1 479.6 | 1 530.4 | 1 612.9 |
| 58 | 1 473.2 | 1 536.7 | 1 587.5 | 1 663.7 |
| 60 | 1 530.4 | 1 593.9 | 1 644.7 | 1 733.6 |
Engineering Notes — Millimetres
Class 600 SI dimensional values separated from the supplied ASME B16.20-2023 source tables.
- D1 is taken from Table SW-2.1-6, Class 600.
- D2, D3 and D4 are taken from the applicable Class 600 data in Table SW-2.1-3.
- D2 is gasket inside diameter, D3 is gasket outside diameter and D4 is centering-ring outside diameter.
- A dash (-) is shown wherever the supplied source contains a note reference instead of a dimensional value.
| NPS |
D1 Inner Ring ID |
D2 Gasket ID |
D3 Gasket OD |
D4 Centering Ring OD |
|---|---|---|---|---|
| ½ | 0.56 | 0.75 | 1.25 | 2.13 |
| ¾ | 0.81 | 1.00 | 1.56 | 2.63 |
| 1 | 1.06 | 1.25 | 1.88 | 2.88 |
| 1¼ | 1.50 | 1.88 | 2.38 | 3.25 |
| 1½ | 1.75 | 2.13 | 2.75 | 3.75 |
| 2 | 2.19 | 2.75 | 3.38 | 4.38 |
| 2½ | 2.62 | 3.25 | 3.88 | 5.13 |
| 3 | 3.19 | 4.00 | 4.75 | 5.88 |
| 3½ | 3.60 | 4.13 | 5.25 | 6.38 |
| 4 | 4.04 | 4.75 | 5.88 | 7.63 |
| 5 | 5.05 | 5.81 | 7.00 | 9.50 |
| 6 | 6.10 | 6.88 | 8.25 | 10.50 |
| 8 | 8.10 | 8.88 | 10.38 | 12.63 |
| 10 | 10.05 | 10.81 | 12.50 | 15.75 |
| 12 | 12.10 | 12.88 | 14.75 | 18.00 |
| 14 | 13.50 | 14.25 | 16.00 | 19.38 |
| 16 | 15.35 | 16.25 | 18.25 | 22.25 |
| 18 | 17.25 | 18.50 | 20.75 | 24.13 |
| 20 | 19.25 | 20.50 | 22.75 | 26.88 |
| 22 | 21.50 | 22.75 | 24.63 | 28.88 |
| 24 | 23.25 | 24.75 | 27.00 | 31.13 |
Engineering Notes — Inches
Class 600 U.S. customary dimensional values separated from the supplied ASME B16.20-2023 source tables.
- D1 uses the Class 600 inch value associated with Table SW-2.1-4.
- D2, D3 and D4 are taken from the applicable U.S. customary Class 600 data in Table SW-2.1-1.
- These inch dimensions are source values and have not been generated by converting the millimetre table.
- A dash (-) is shown wherever the supplied source contains a note reference instead of a dimensional value.
| NPS |
D1 Inner Ring ID |
D2 Gasket ID |
D3 Gasket OD |
D4 Centering Ring OD |
|---|---|---|---|---|
| ½ | 14.2 | 19.1 | 31.8 | 54.1 |
| ¾ | 20.6 | 25.4 | 39.6 | 66.8 |
| 1 | 26.9 | 31.8 | 47.8 | 73.2 |
| 1¼ | 38.1 | 47.8 | 60.5 | 82.6 |
| 1½ | 44.5 | 54.1 | 69.9 | 95.3 |
| 2 | 55.6 | 69.9 | 85.9 | 111.3 |
| 2½ | 66.5 | 82.6 | 98.6 | 130.3 |
| 3 | 81.0 | 101.6 | 120.7 | 149.4 |
| 3½ | 91.4 | 104.8 | 133.4 | 161.9 |
| 4 | 102.6 | 120.7 | 149.4 | 193.8 |
| 5 | 128.3 | 147.6 | 177.8 | 241.3 |
| 6 | 154.9 | 174.8 | 209.6 | 266.7 |
| 8 | 205.7 | 225.6 | 263.7 | 320.8 |
| 10 | 255.3 | 274.6 | 317.5 | 400.1 |
| 12 | 307.3 | 327.2 | 374.7 | 457.2 |
| 14 | 342.9 | 362.0 | 406.4 | 492.3 |
| 16 | 389.9 | 412.8 | 463.6 | 565.2 |
| 18 | 438.2 | 469.9 | 527.1 | 612.9 |
| 20 | 489.0 | 520.7 | 577.9 | 682.6 |
| 22 | 546.2 | 577.9 | 625.5 | 733.6 |
| 24 | 590.6 | 628.7 | 685.8 | 790.7 |
Engineering Notes — Millimetres
Class 600 SI dimensional values separated from the supplied ASME B16.20-2023 source tables.
- D1 is taken from Table SW-2.1-4, Class 600.
- D2, D3 and D4 are taken from the applicable Class 600 data in Table SW-2.1-1.
- D2 is gasket inside diameter, D3 is gasket outside diameter and D4 is centering-ring outside diameter.
- A dash (-) is shown wherever the supplied source contains a note reference instead of a dimensional value.
| NPS |
D1 Inner Ring ID |
D2 Gasket ID |
D3 Gasket OD |
D4 Centering Ring OD |
|---|---|---|---|---|
| 26 | 26.00 | 27.00 | 29.00 | 34.75 |
| 28 | 28.00 | 29.00 | 31.00 | 37.25 |
| 30 | 30.25 | 31.25 | 33.25 | 39.75 |
| 32 | 32.00 | 33.50 | 35.50 | 42.25 |
| 34 | 34.00 | 35.50 | 37.50 | 44.75 |
| 36 | 36.25 | 37.75 | 39.75 | 47.25 |
| 38 | 39.75 | 40.75 | 42.75 | 47.25 |
| 40 | 41.75 | 43.25 | 45.25 | 49.25 |
| 42 | 43.75 | 45.25 | 47.25 | 51.25 |
| 44 | 45.50 | 47.50 | 49.50 | 53.88 |
| 46 | 48.00 | 50.00 | 52.00 | 56.50 |
| 48 | 50.00 | 52.00 | 54.00 | 58.50 |
| 50 | - | - | - | - |
| 52 | - | - | - | - |
| 54 | - | - | - | - |
| 56 | - | - | - | - |
| 58 | - | - | - | - |
| 60 | - | - | - | - |
Engineering Notes — Inches
Class 900 U.S. customary dimensional values separated from the supplied ASME B16.20-2023 source tables.
- D1 uses the Class 900 inch value associated with Table SW-2.1-5.
- D2, D3 and D4 are taken from the applicable U.S. customary Class 900 data in Table SW-2.1-2.
- These inch dimensions are source values and have not been generated by converting the millimetre table.
- A dash (-) is shown wherever the supplied source contains a note reference instead of a dimensional value.
| NPS |
D1 Inner Ring ID |
D2 Gasket ID |
D3 Gasket OD |
D4 Centering Ring OD |
|---|---|---|---|---|
| 26 | 660.4 | 685.8 | 736.6 | 882.7 |
| 28 | 711.2 | 736.6 | 787.4 | 946.2 |
| 30 | 768.4 | 793.8 | 844.6 | 1 009.7 |
| 32 | 812.8 | 850.9 | 901.7 | 1 073.2 |
| 34 | 863.6 | 901.7 | 952.5 | 1 136.7 |
| 36 | 920.8 | 958.9 | 1 009.7 | 1 200.2 |
| 38 | 1 009.7 | 1 035.1 | 1 085.9 | 1 200.2 |
| 40 | 1 060.5 | 1 098.6 | 1 149.4 | 1 251.0 |
| 42 | 1 111.3 | 1 149.4 | 1 200.2 | 1 301.8 |
| 44 | 1 155.7 | 1 206.5 | 1 257.3 | 1 368.6 |
| 46 | 1 219.2 | 1 270.0 | 1 320.8 | 1 435.1 |
| 48 | 1 270.0 | 1 320.8 | 1 371.6 | 1 485.9 |
| 50 | - | - | - | - |
| 52 | - | - | - | - |
| 54 | - | - | - | - |
| 56 | - | - | - | - |
| 58 | - | - | - | - |
| 60 | - | - | - | - |
Engineering Notes — Millimetres
Class 900 SI dimensional values separated from the supplied ASME B16.20-2023 source tables.
- D1 is taken from Table SW-2.1-5, Class 900.
- D2, D3 and D4 are taken from the applicable Class 900 data in Table SW-2.1-2.
- D2 is gasket inside diameter, D3 is gasket outside diameter and D4 is centering-ring outside diameter.
- A dash (-) is shown wherever the supplied source contains a note reference instead of a dimensional value.
| NPS |
D1 Inner Ring ID |
D2 Gasket ID |
D3 Gasket OD |
D4 Centering Ring OD |
|---|---|---|---|---|
| 26 | 26.25 | 27.25 | 29.50 | 33.00 |
| 28 | 28.25 | 29.25 | 31.50 | 35.50 |
| 30 | 30.75 | 31.75 | 33.75 | 37.75 |
| 32 | 33.00 | 34.00 | 36.00 | 40.00 |
| 34 | 35.25 | 36.25 | 38.25 | 42.25 |
| 36 | 36.25 | 37.25 | 39.25 | 44.25 |
| 38 | 39.75 | 40.75 | 42.75 | 47.25 |
| 40 | 41.75 | 43.25 | 45.25 | 49.25 |
| 42 | 43.75 | 45.25 | 47.25 | 51.25 |
| 44 | 45.50 | 47.50 | 49.50 | 53.88 |
| 46 | 48.00 | 50.00 | 52.00 | 56.50 |
| 48 | 50.00 | 52.00 | 54.00 | 58.50 |
| 50 | - | - | - | - |
| 52 | - | - | - | - |
| 54 | - | - | - | - |
| 56 | - | - | - | - |
| 58 | - | - | - | - |
| 60 | - | - | - | - |
Engineering Notes — Inches
Class 900 U.S. customary dimensional values separated from the supplied ASME B16.20-2023 source tables.
- D1 uses the Class 900 inch value associated with Table SW-2.1-6.
- D2, D3 and D4 are taken from the applicable U.S. customary Class 900 data in Table SW-2.1-3.
- These inch dimensions are source values and have not been generated by converting the millimetre table.
- A dash (-) is shown wherever the supplied source contains a note reference instead of a dimensional value.
| NPS |
D1 Inner Ring ID |
D2 Gasket ID |
D3 Gasket OD |
D4 Centering Ring OD |
|---|---|---|---|---|
| 26 | 666.8 | 692.2 | 749.3 | 838.2 |
| 28 | 717.6 | 743.0 | 800.1 | 901.7 |
| 30 | 781.1 | 806.5 | 857.3 | 958.9 |
| 32 | 838.2 | 863.6 | 914.4 | 1 016.0 |
| 34 | 895.4 | 920.8 | 971.6 | 1 073.2 |
| 36 | 920.8 | 946.2 | 997.0 | 1 124.0 |
| 38 | 1 009.7 | 1 035.1 | 1 085.9 | 1 200.2 |
| 40 | 1 060.5 | 1 098.6 | 1 149.4 | 1 251.0 |
| 42 | 1 111.3 | 1 149.4 | 1 200.2 | 1 301.8 |
| 44 | 1 155.7 | 1 206.5 | 1 257.3 | 1 368.6 |
| 46 | 1 219.2 | 1 270.0 | 1 320.8 | 1 435.1 |
| 48 | 1 270.0 | 1 320.8 | 1 371.6 | 1 485.9 |
| 50 | - | - | - | - |
| 52 | - | - | - | - |
| 54 | - | - | - | - |
| 56 | - | - | - | - |
| 58 | - | - | - | - |
| 60 | - | - | - | - |
Engineering Notes — Millimetres
Class 900 SI dimensional values separated from the supplied ASME B16.20-2023 source tables.
- D1 is taken from Table SW-2.1-6, Class 900.
- D2, D3 and D4 are taken from the applicable Class 900 data in Table SW-2.1-3.
- D2 is gasket inside diameter, D3 is gasket outside diameter and D4 is centering-ring outside diameter.
- A dash (-) is shown wherever the supplied source contains a note reference instead of a dimensional value.
| NPS |
D1 Inner Ring ID |
D2 Gasket ID |
D3 Gasket OD |
D4 Centering Ring OD |
|---|---|---|---|---|
| ½ | - | - | 1.25 | - |
| ¾ | - | - | 1.56 | - |
| 1 | - | - | 1.88 | - |
| 1¼ | - | - | 2.38 | - |
| 1½ | - | - | 2.75 | - |
| 2 | - | - | 3.38 | - |
| 2½ | - | - | 3.88 | - |
| 3 | 3.10 | 3.75 | 4.75 | 6.63 |
| 3½ | - | - | - | - |
| 4 | 4.04 | 4.75 | 5.88 | 8.13 |
| 5 | 5.05 | 5.81 | 7.00 | 9.75 |
| 6 | 6.10 | 6.88 | 8.25 | 11.38 |
| 8 | 7.75 | 8.75 | 10.13 | 14.13 |
| 10 | 9.69 | 10.88 | 12.25 | 17.13 |
| 12 | 11.50 | 12.75 | 14.50 | 19.63 |
| 14 | 12.63 | 14.00 | 15.75 | 20.50 |
| 16 | 14.75 | 16.25 | 18.00 | 22.63 |
| 18 | 16.75 | 18.25 | 20.50 | 25.13 |
| 20 | 19.00 | 20.50 | 22.50 | 27.50 |
| 22 | - | - | - | - |
| 24 | 23.25 | 24.75 | 26.75 | 33.00 |
Engineering Notes — Inches
Class 900 U.S. customary dimensional values separated from the supplied ASME B16.20-2023 source tables.
- D1 uses the Class 900 inch value associated with Table SW-2.1-4.
- D2, D3 and D4 are taken from the applicable U.S. customary Class 900 data in Table SW-2.1-1.
- These inch dimensions are source values and have not been generated by converting the millimetre table.
- A dash (-) is shown wherever the supplied source contains a note reference instead of a dimensional value.
| NPS |
D1 Inner Ring ID |
D2 Gasket ID |
D3 Gasket OD |
D4 Centering Ring OD |
|---|---|---|---|---|
| ½ | - | - | 31.8 | - |
| ¾ | - | - | 39.6 | - |
| 1 | - | - | 47.8 | - |
| 1¼ | - | - | 60.5 | - |
| 1½ | - | - | 69.9 | - |
| 2 | - | - | 85.9 | - |
| 2½ | - | - | 98.6 | - |
| 3 | 78.7 | 95.3 | 120.7 | 168.4 |
| 3½ | - | - | - | - |
| 4 | 102.6 | 120.7 | 149.4 | 206.5 |
| 5 | 128.3 | 147.6 | 177.8 | 247.7 |
| 6 | 154.9 | 174.8 | 209.6 | 289.1 |
| 8 | 196.9 | 222.3 | 257.3 | 358.9 |
| 10 | 246.1 | 276.4 | 311.2 | 435.1 |
| 12 | 292.1 | 323.9 | 368.3 | 498.6 |
| 14 | 320.8 | 355.6 | 400.1 | 520.7 |
| 16 | 374.7 | 412.8 | 457.2 | 574.8 |
| 18 | 425.5 | 463.6 | 520.7 | 638.3 |
| 20 | 482.6 | 520.7 | 571.5 | 698.5 |
| 22 | - | - | - | - |
| 24 | 590.6 | 628.7 | 679.5 | 838.2 |
Engineering Notes — Millimetres
Class 900 SI dimensional values separated from the supplied ASME B16.20-2023 source tables.
- D1 is taken from Table SW-2.1-4, Class 900.
- D2, D3 and D4 are taken from the applicable Class 900 data in Table SW-2.1-1.
- D2 is gasket inside diameter, D3 is gasket outside diameter and D4 is centering-ring outside diameter.
- A dash (-) is shown wherever the supplied source contains a note reference instead of a dimensional value.
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