ASME B16.20 Ring Joint Gasket Dimensions — Type R
Dimensions of ASME B16.20 type R ring joint gaskets (oval and octagonal) in millimetres, with the ASME B16.5 flange size each ring number fits in each pressure class.
Ring joint gaskets are solid metal rings that seal in the groove of a ring type joint (RTJ) flange. Oval and octagonal rings of the same number are interchangeable in modern flat-bottom grooves.
Key to dimensions
- P
- Pitch diameter of ring
- A
- Width of ring
- B
- Height of oval ring
- H
- Height of octagonal ring
- C
- Width of flat on octagonal ring
ASME B16.20 Ring Joint Gasket dimensions — Type R — tables
Type R ring joint gaskets (mm) and flange size by class
| Ring no. | PPitch dia | AWidth | BOval height | HOctagonal height | CFlat width | Class 150NPS | Class 300–600NPS | Class 900NPS | Class 1500NPS | Class 2500NPS |
|---|---|---|---|---|---|---|---|---|---|---|
| R11 | 34.14 | 6.35 | 11.2 | 9.7 | 4.32 | — | ½" | — | — | — |
| R12 | 39.70 | 7.95 | 14.2 | 12.7 | 5.23 | — | — | ½" | ½" | — |
| R13 | 42.88 | 7.95 | 14.2 | 12.7 | 5.23 | — | ¾" | — | — | ½" |
| R14 | 44.45 | 7.95 | 14.2 | 12.7 | 5.23 | — | — | ¾" | ¾" | — |
| R15 | 47.63 | 7.95 | 14.2 | 12.7 | 5.23 | 1" | — | — | — | — |
| R16 | 50.80 | 7.95 | 14.2 | 12.7 | 5.23 | — | 1" | 1" | 1" | ¾" |
| R17 | 57.15 | 7.95 | 14.2 | 12.7 | 5.23 | 1¼" | — | — | — | — |
| R18 | 60.33 | 7.95 | 14.2 | 12.7 | 5.23 | — | 1¼" | 1¼" | 1¼" | 1" |
| R19 | 65.10 | 7.95 | 14.2 | 12.7 | 5.23 | 1½" | — | — | — | — |
| R20 | 68.28 | 7.95 | 14.2 | 12.7 | 5.23 | — | 1½" | 1½" | 1½" | — |
| R21 | 72.24 | 11.13 | 17.5 | 16.0 | 7.75 | — | — | — | — | 1¼" |
| R22 | 82.55 | 7.95 | 14.2 | 12.7 | 5.23 | 2" | — | — | — | — |
| R23 | 82.55 | 11.13 | 17.5 | 16.0 | 7.75 | — | 2" | — | — | 1½" |
| R24 | 95.25 | 11.13 | 17.5 | 16.0 | 7.75 | — | — | 2" | 2" | — |
| R25 | 101.60 | 7.95 | 14.2 | 12.7 | 5.23 | 2½" | — | — | — | — |
| R26 | 101.60 | 11.13 | 17.5 | 16.0 | 7.75 | — | 2½" | — | — | 2" |
| R27 | 107.95 | 11.13 | 17.5 | 16.0 | 7.75 | — | — | 2½" | 2½" | — |
| R28 | 111.13 | 12.70 | 19.1 | 17.5 | 8.66 | — | — | — | — | 2½" |
| R29 | 114.30 | 7.95 | 14.2 | 12.7 | 5.23 | 3" | — | — | — | — |
| R30 (lapped joint) | 117.48 | 11.13 | 17.5 | 16.0 | 7.75 | — | 3" | — | — | — |
| R31 | 123.83 | 11.13 | 17.5 | 16.0 | 7.75 | — | 3" | 3" | — | — |
| R32 | 127.00 | 12.70 | 19.1 | 17.5 | 8.66 | — | — | — | — | 3" |
| R33 | 131.78 | 7.95 | 14.2 | 12.7 | 5.23 | 3½" | — | — | — | — |
| R34 | 131.78 | 11.13 | 17.5 | 16.0 | 7.75 | — | 3½" | — | — | — |
| R35 | 136.53 | 11.13 | 17.5 | 16.0 | 7.75 | — | — | — | 3" | — |
| R36 | 149.23 | 7.95 | 14.2 | 12.7 | 5.23 | 4" | — | — | — | — |
| R37 | 149.23 | 11.13 | 17.5 | 16.0 | 7.75 | — | 4" | 4" | — | — |
| R38 | 157.18 | 15.88 | 22.4 | 20.6 | 10.49 | — | — | — | — | 4" |
| R39 | 161.93 | 11.13 | 17.5 | 16.0 | 7.75 | — | — | — | 4" | — |
| R40 | 171.45 | 7.95 | 14.2 | 12.7 | 5.23 | 5" | — | — | — | — |
| R41 | 180.98 | 11.13 | 17.5 | 16.0 | 7.75 | — | 5" | 5" | — | — |
| R42 | 190.50 | 19.05 | 25.4 | 23.9 | 12.32 | — | — | — | — | 5" |
| R43 | 193.68 | 7.95 | 14.2 | 12.7 | 5.23 | 6" | — | — | — | — |
| R44 | 193.68 | 11.13 | 17.5 | 16.0 | 7.75 | — | — | — | 5" | — |
| R45 | 211.15 | 11.13 | 17.5 | 16.0 | 7.75 | — | 6" | 6" | — | — |
| R46 | 211.15 | 12.70 | 19.1 | 17.5 | 8.66 | — | — | — | 6" | — |
| R47 | 228.60 | 19.05 | 25.4 | 23.9 | 12.32 | — | — | — | — | 6" |
| R48 | 247.65 | 7.95 | 14.2 | 12.7 | 5.23 | 8" | — | — | — | — |
| R49 | 269.88 | 11.13 | 17.5 | 16.0 | 7.75 | — | 8" | 8" | — | — |
| R50 | 269.88 | 15.88 | 22.4 | 20.6 | 10.49 | — | — | — | 8" | — |
| R51 | 279.40 | 22.23 | 28.7 | 26.9 | 14.81 | — | — | — | — | 8" |
| R52 | 304.80 | 7.95 | 14.2 | 12.7 | 5.23 | 10" | — | — | — | — |
| R53 | 323.85 | 11.13 | 17.5 | 16.0 | 7.75 | — | 10" | 10" | — | — |
| R54 | 323.85 | 15.88 | 22.4 | 20.6 | 10.49 | — | — | — | 10" | — |
| R55 | 342.90 | 28.58 | 36.6 | 35.1 | 19.81 | — | — | — | — | 10" |
| R56 | 381.00 | 7.95 | 14.2 | 12.7 | 5.23 | 12" | — | — | — | — |
| R57 | 381.00 | 11.13 | 17.5 | 16.0 | 7.75 | — | 12" | 12" | — | — |
| R58 | 381.00 | 22.23 | 28.7 | 26.9 | 14.81 | — | — | — | 12" | — |
| R59 | 396.88 | 7.95 | 14.2 | 12.7 | 5.23 | 14" | — | — | — | — |
| R60 | 406.40 | 31.75 | 39.6 | 38.1 | 22.33 | — | — | — | — | 12" |
| R61 | 419.10 | 11.13 | 17.5 | 16.0 | 7.75 | — | 14" | — | — | — |
| R62 | 419.10 | 15.88 | 22.4 | 20.6 | 10.49 | — | — | 14" | — | — |
| R63 | 419.10 | 25.40 | 33.3 | 31.8 | 17.30 | — | — | — | 14" | — |
| R64 | 454.03 | 7.95 | 14.2 | 12.7 | 5.23 | 16" | — | — | — | — |
| R65 | 469.90 | 11.13 | 17.5 | 16.0 | 7.75 | — | 16" | — | — | — |
| R66 | 469.90 | 15.88 | 22.4 | 20.6 | 10.49 | — | — | 16" | — | — |
| R67 | 469.90 | 28.58 | 36.6 | 35.1 | 19.81 | — | — | — | 16" | — |
| R68 | 517.53 | 7.95 | 14.2 | 12.7 | 5.23 | 18" | — | — | — | — |
| R69 | 533.40 | 11.13 | 17.5 | 16.0 | 7.75 | — | 18" | — | — | — |
| R70 | 533.40 | 19.05 | 25.4 | 23.9 | 12.32 | — | — | 18" | — | — |
| R71 | 533.40 | 28.58 | 36.6 | 35.1 | 19.81 | — | — | — | 18" | — |
| R72 | 558.80 | 7.95 | 14.2 | 12.7 | 5.23 | 20" | — | — | — | — |
| R73 | 584.20 | 12.70 | 19.1 | 17.5 | 8.66 | — | 20" | — | — | — |
| R74 | 584.20 | 19.05 | 25.4 | 23.9 | 12.32 | — | — | 20" | — | — |
| R75 | 584.20 | 31.75 | 39.6 | 38.1 | 22.33 | — | — | — | 20" | — |
| R76 | 673.10 | 7.95 | 14.2 | 12.7 | 5.23 | 24" | — | — | — | — |
| R77 | 692.15 | 15.88 | 22.4 | 20.6 | 10.49 | — | 24" | — | — | — |
| R78 | 692.15 | 25.40 | 33.3 | 31.8 | 17.30 | — | — | 24" | — | — |
| R79 | 692.15 | 34.93 | 44.5 | 41.4 | 24.82 | — | — | — | 24" | — |
Notes
- Dimensions are in millimetres unless stated otherwise.
- Ring number R30 is for lapped joints only.
- Confirm the ring number against the flange drawing before ordering.
Reference information compiled from the published standard for convenience. It does not replace the current edition of the governing standard, which takes precedence. Verify critical dimensions and properties before design, purchase or fabrication. Teshi Engineers & Sales Promoters (P) Ltd accepts no liability for errors or omissions.
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NPS ½"–60" · Metallic / Soft
OpenOEM manufacturerIndustrial Flanges
NPS ½"–60" · CS / SS / Alloy
OpenEquivalent and related standards to ASME B16.20 Ring Joint Gasket Dimensions
All equivalents| Region | Standard | Relationship |
|---|---|---|
| Europe | EN 1514-1 / -2 / -4 / EN 12560 | Gaskets for PN and Class flanges |
| China | GB/T 4622.2 / HG/T 20610 / HG/T 20631 | Spiral-wound gaskets for PN and Class flanges |
| China | HG/T 20612 / HG/T 20633 | Ring joint and metal gaskets |
| Japan | JIS B2404 | Gasket dimensions for JIS flanges |
Teshi Group manufactures flanges and fittings to all of these standards on request, including Chinese GB / HG / SH and European EN dimensions for export projects. Always confirm bolting, facing and thickness when substituting one standard for another.
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