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All About Ring Type Joint Flanges

Ring type joint flange

Ring type joint flange face surfaces are an increasingly popular option with regards to flange connections. RTJ Flanges are a  good alternative to raised face in certain applications. Typically, higher pressure and temperature projects use Ring Type Joints.

They provide a more effective sealing solution to media critical pipeline and pressure vessel infrastructure. Although only an option in ANSI/ASME class flanges, they are the required standard surface sealing in API specification flanges.

This is due to the fact that API flanges typically operate at a higher pressure in comparison to their ANSI/ASME flange counterparts.

The seal of an RTJ gasket occurs under the force of closing the bolt and hardware after mating one flange to another. Typically, the gaskets are made of softer material than the metal of the flanges they are sealing.

The most common of these materials is a soft iron. Slow and steady pressure on the hardware of the flange”crushes” the gasket within the ring joint surface. This helps to prevent any type of leakage during operation of the flange assembly.

Ring Type Joint gaskets are designated by an “R” number. R gaskets are available in oval and octagonal configuration. Given the smooth sealing surface of ring joint faces, both configurations are virtually interchangeable.

When in doubt, higher pressure and temperature applications typically call for ring joint facings. When optimal surface sealing is necessary, Ring Type Joint flanges are the ideal choice.

Give us a call at 281-484-8325 or shoot us an email at [email protected] with any questions or concerns on your order.



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Rob Stephens
Rob Stephens
3 years ago

should a RJ lfg be used at 815 Deg C at 5barg? RF flanges have been specified. Thank you for your response

3 years ago
Reply to  Rob Stephens

Depends on the pressure class and media in use. While we don’t have engineers on staff to make a recommendation for your application, we’d be happy to price it both ways.