What are the types and uses of common standard flanges?

Common flanges are standard series flanges selected according to the properties of the medium (such as the corrosiveness, flammability, explosiveness, permeability, etc.) of the medium, temperature and pressure parameters. For non-standard series flanges, generally need to design and calculate by themselves according to requirements. In general, according to the structure of the flange, it can be divided into five types: smooth face flat welding flange, convex face flat welding flange, smooth face welding flange, convex face welding flange and trapezoidal groove face welding.

  For smooth surface flat welding flanges, it is mainly suitable for general media with working pressure PN <2.5MPa and temperature f <300 ° C; and flat surface flat welding flanges are suitable for working pressure PN <2.5MPa, Flammable and explosive, toxic and irritating medium with temperature f <300 ° C, or requiring strict sealing.

  For smooth face welding flanges, it is mainly suitable for general media with working pressure PN <4.0MPa and temperature (> 300 ° C), while concave and convex face welding flanges are suitable for medium and high pressure general media and work. Inflammable, explosive, toxic and irritating media with pressure PN <6.4MPa and temperature> 300 ° C, or requiring strict sealing.

  The trapezoidal groove facing welding flange is mainly used for the working pressure of 6.4MPa <PN <16MPa, soda pipes or medium and high pressure oil and similar media with special requirements.