The determination criterion of heating temperature for carbon steel elbow pipe fittings is that the austenitizing temperature and the main compressive stress in the inner wall of elbow pipe fittings are less than the yield limit of data at this temperature.  Large diameter high pressure flanges are widely used in industrial pipelines.  

In the face of flange products, the first thing to see the surface finish, sand holes or cracks are not allowed to exist.  This requires the use of conditions to be smooth, avoid pressure and temperature shake sharply, in the use of a period of time and then tighten the bolt, its hot and cold cycle is particularly important for high temperature and application occasions.  

Most gaskets are cut from non-metallic sheets or professionally made to specified sizes, such as asbestos rubber sheets, asbestos sheets, polyethylene sheets, etc.  There is also a wound washer made of a thin steel strip of asbestos tape.  

Flange is mainly used in the installation of large-caliber high-pressure pipeline. Large-caliber high-pressure flange connection is an important connection mode in pipeline construction. The primary connection between pipelines plays a very important role and value.