Flange Facing Types
- Flat Face (FF) – Typically these flanges are used on pump facings or on fiberglass flanges where the torque of compressing the gasket will damage the flange body. They are found in 150# and 300# ratings. Their principal use is to make connections with 125# and 250# cast iron flanges, respectively.
- Raised Face (RF) – The raised face is the most common used flange face. It is called raised face because the gasket is raised 1/16″ and 1/4″ above the bolt circle face: 1/16″ for 300 lb. and less, 1/4″ for 400 lb. and more. The flange facings are machine finished toANSI/ASME B16.5 requirements.
- Ring Type Joint (RTJ) (Class 300 and larger) – This flange is normally used for high pressure gas pipe work. Ring type gaskets must be used on this type of flange.
- Tongue and Groove (T&G)
- Small Tongue and Groove
- Large Tongue and Groove
- Small Male and Female
- Large Male and Female