Can you use a flat face gasket on a raised face flange?
Flat face flanges are never to be bolted to a raised face flange. ASME B31. 1 says that when connecting flat face cast iron flanges to carbon steel flanges, the raised face on the carbon steel flange must be removed, and that a full face gasket is required.
What is a raised face Slip on flange?
Stainless Steel Slip On Raised Face Flanges is referred to as a raised face because the gasket surfaces are raised above the bolting circle face. Carbon Steel Slip On Raised Face Flanges are manufactured with an inside diameter that is slightly bigger than the pipe’s outside diameter.
What is flat face flange?
Flat faced flange, abbreviated as FF, is a flange that is machined flat and does not have a ridge like a raised face or ring type joint flange. The flat surface allows for the gasket to have full contact with the entire mating surface. Usually gaskets are made from non-metallic materials such as EPDM or Viton.
What is the difference between RTJ and RF?
RTJ flanges have grooves in their sealing faces, while RF flanges do not. If you want to make a connection between the two flanges, you can only apply a flat gasket. This flat gasket wil be make full contact with de sealing surface of the RF flange, but not with the sealing surface of the RTJ flange.
What is the standard type of finish on raised face flanges?
The raised face is furnished with concentric serrated finish. The facing finish or face finish of a pipe flange manufactured in accordance with ASME B16. 5 refers to the smoothness or roughness of the facing surface.
How many types of face flanges are there?
The 6 available types of flange face are flat (FF), raised (RF), ring joint (RTJ), lap joint, male and female (M&F), tongue and groove (T&G). Flanges with different faces require different gaskets and shall never be mated to prevent leakage of the joint.
Are flat face flanges serrated?
The most common flange face surface designs are smooth and serrated. Flat face (FF) flange surfaces and raised face (RF) flange surfaces require serrations if built to industry standards.
