There are three types of high-pressure flange sealing face: flat sealing face, suitable for low pressure, non-toxic medium occasions; Concave and convex sealing surface, suitable for slightly high pressure occasions; Tenon and groove sealing surface, suitable for flammable, explosive, toxic media and high pressure occasions.

High pressure flange gasket and sealing surface contact width is very narrow (line contact), sealing surface and gasket machining finish is high. Common integral flanges are flat welded flange and butt welded flange. Ordinary rubber gasket is suitable for temperature below 120℃; Asbestos rubber gasket is suitable for water vapor temperature below 450℃, oil temperature below 350℃, pressure below 5MPa, for the general corrosive medium, the most commonly used is acid resistant asbestos board.
Low pressure small diameter wire connected flanges, high pressure and low pressure large diameter are welded flanges, flange thickness and connecting bolt diameter and number of different pressures are different.
Most gaskets are cut from non-metallic plates, or made by professional factories according to the specified size, the material is asbestos rubber board, asbestos board, polyethylene board, etc.; Also useful thin metal plate (iron sheet, stainless steel) asbestos and other non-metallic materials wrapped up made of metal gaskets; There is also a wound type gasket made of thin steel tape and asbestos tape wound together.
High pressure flange connection is a detachable connection. According to the connected parts can be divided into container flange and pipe flange. According to the structure type, there are integral flange, looper flange and threaded flange.
In high pressure equipment and pipes, metal gaskets made of copper, aluminum, No. 10 steel, stainless steel, lens type or other shapes are used. High pressure flange rigidity is poor, suitable for pressure p≤4MPa occasions; High pressure flange, also known as high neck flange, is rigid and suitable for high pressure and temperature occasions. High pressure flange gasket is a kind of ring made of material which can produce plastic deformation and has certain strength.