The octagonal cross section has a higher sealing eﬃciency than the oval and would be the preferred gasket. Only oval cross section can be used in the old type round bottom groove. The newer ﬂat botiom groove design will accept either the oval or the octagonal cross section. They seal by an initial line contact or a wedging action as the compressive forces are applied. The hardness of the ring should always be less than the hardness of the ﬂanges.
Style BX and RX:
The gasket diﬀers from the standard oval or octagonal shape in that it is square in cross section and tapers in each corner. BX can only be used in API 6BX ﬂanges.
RX ring gaskets are similar in shape to the standard octagonal ring joint gasket but their cross section is designed to take advantage of the contained ﬂuid pressure in eﬀecting a seal
Rubber Coated Test Ring
This is a Ring Joint gasket totally enclosed in a Nitrile rubber coating. The Ring Joint gasket material is usually soft iron or low carbon steel. This gasket is designed for multiple uses as a test ring.
Quest was ﬁrst to introduced a new ﬂange test seal, which is both superior in performance to rubber seals and capable of being reused 10 x more than the conventional test rings, thus saving on costs.
Eco—Test Rings ﬁts all standard R, RX and BX housings and is available in any diameter.