Performance and Application of Large Flanges
Large flanges develop variously useful values in application, which have kinds of effects and purposes. The techniques of process and production vary due to its different materials. Therefore, certain procedures and methods should be applied when using and processing large flanges.
The integrated flange is a more common kind of large flange, which can be divided into slip on flanges and butt welded flanges. Due to poor rigidity, slip on flanges
can only be used in the situation where the pressure is less than or equal to 4MPa. Butt welded flanges, also called welding neck flanges
, are stiff enough to adapt to places with high temperature and pressure.
have three kinds of sealing surfaces: flat style, used in places of low pressure and non-toxic medium; concave-convex style, applied to higher pressure situation; tongue-and-groove style, which is flexibly used to higher pressure occasion and flammable, explosive or toxic medium. Different flanged pipe fittings perform well in different areas. To adapt to various occasions and space, their effects will also be diverse.
Gaskets of large flanges are circles made from certainly strong materials with the ability of plastic deformation.
Most gaskets are cut from nonmetallic plates, or made by professional factory at a specified dimension. The materials of this kinds gaskets are paronites, asbestos plates, polythene sheeting and so on; also there is a kind of mental cladding gasket which is made by wrapping asbestos and other nonmetal materials with sheet metal(galvanized iron sheet or stainless steel); in addition, there is a spiral wound gasket twined by stalloys and asbestos tapes.
When used in pipes and high-tension equipment, the applied gaskets of flanges are usually made from copper, aluminum, soft steel of lens type or other-shape mental gaskets.The contact width (line contact) between a high pressure gasket and its sealing surface is narrow. However, the smoothness of gaskets and sealing surfaces are great.