The RTJ flange (Ring Type Jiont) is designed for high-pressure and/or hight-temperature pipeline applications.This makes them the require standard in API specification flanges. Applications include oil field valves,pipework assemblies,and high integrity pressure vessel joints.Like other flanges,they use a gasket under compression to creat a secure joint. But an RTJ flange differs from the more common flat and raised face flange in several ways:

1.The gasket used is a steel ring-instead of the flat composite material type.

2.An RTJ flange has a groove machined into the flange surface to accept the gasket.

3.When the gasket deforms it creats a metal-to-metal seal.

4.Under compression,the softer metal of the gasket flow into the microfine structure of the harder flange material.

5.The raised faces of connected and tightened RTJ flanges may be in contact with each other.When this happens,the compressed gasket will not bear any extra load.The benefit is the integrity of joint will be protected from over-tightening,vibration,and movement.