The tables below list all the relevant size information for gaskets made to suit BS 3063 Table D or Table E flanges in the Ring Face (i.e. no bolt holes) style.
In some cases (especially with smaller gaskets but not limited to these) a certain nominal bore gasket will fit both Table D and Table E flanges. When this occurs it is noted in the Matches Table column of the table(s).
This style of gasket is designed to sit inside the bolts of the flanges and is known by quite a few names, including:
- RF Flange Gaskets.
- IBC Gaskets (Inner Bolt Circle).
- Raised Face Gaskets (as they are often used on raised face type flanges).
- Ring Face Gaskets.
Gasket Measurement Terms Used.
Gasket OD: Outside Diameter of the Gasket.
Gasket ID: Inside Diameter of the Gasket (Centre Hole). If there is no centre hole it is known as a "Blind Gasket". These are typically used at the end of pipelines and can be produced upon request.
BS 3063 Table D Ring Face Flange Gasket Size Table.
All Dimensions below are given in millimeters (mm).
| Flange Nominal Bore |
Imperial Short-Hand |
Gasket ID | Gasket OD | Matches Table |
| 15NB | 1/2" | 21 | 52 | E |
| 20NB | 3/4" | 27 | 59 | E |
| 25NB | 1" | 34 | 68 | E |
| 32NB | 1 1/4" | 43 | 73 | E |
| 40NB | 1 1/2" | 48 | 84 | E |
| 50NB | 2" | 60 | 97 | E |
| 65NB | 2 1/2" | 76 | 110 | E |
| 80NB | 3" | 89 | 129 | E |
| 90NB | 3 1/2" | 102 | 148 | E |
| 100NB | 4" | 114 | 160 | E |
| 125NB | 5" | 140 | 191 | E |
| 150NB | 6" | 168 | 216 | - |
| 200NB | 8" | 219 | 273 | - |
| 250NB | 10" | 273 | 333 | E |
| 300NB | 12" | 324 | 384 | - |
| 350NB | 14" | 381 | 444.5 | E |
| 400NB | 16" | 432 | 495 | E |
| 450NB | 18" | 483 | 559 | E |
| 500NB | 20" | 533 | 616 | E |
| 600NB | 24" | 635 | 728 | E |
BS 3063 Table E Ring Face Flange Gasket Size Table.
All Dimensions below are given in millimeters (mm).
| Flange Nominal Bore |
Imperial Short-Hand |
Gasket ID | Gasket OD | Matches Table |
| 15NB | 1/2" | 21 | 52 | D |
| 20NB | 3/4" | 27 | 59 | D |
| 25NB | 1" | 34 | 68 | D |
| 32NB | 1 1/4" | 43 | 73 | D |
| 40NB | 1 1/2" | 48 | 84 | D |
| 50NB | 2" | 60 | 97 | D |
| 65NB | 2 1/2" | 76 | 110 | D |
| 80NB | 3" | 89 | 129 | D |
| 90NB | 3 1/2" | 102 | 148 | D |
| 100NB | 4" | 114 | 160 | D |
| 125NB | 5" | 140 | 191 | D |
| 150NB | 6" | 168 | 213 | - |
| 200NB | 8" | 219 | 270 | - |
| 250NB | 10" | 273 | 333 | D |
| 300NB | 12" | 324 | 381 | - |
| 350NB | 14" | 381 | 444.5 | D |
| 400NB | 16" | 432 | 495 | D |
| 450NB | 18" | 483 | 559 | D |
| 500NB | 20" | 533 | 616 | D |
| 600NB | 24" | 635 | 728 | D |
Other Flange Specification Sizing
If the gasket size you're looking for isn't listed on any of the above tables it may suit a different flange spec. We have sizing tables for many of the most common ones used in Australia. You can access our current list via our Flange Table Gasket Dimensions Menu Page.
For more information, help finding the correct sizing or to enquire about custom cut gaskets in all kinds of materials and sizes, please do contact us.