welding neck flange is also known as the welding neck flange, it differed from the slip on flange is from the flange to pipe welding of flange that has a long sloping high neck, the high cervical wall thickness along the height direction gradually transition to the pipe wall thickness, improve the force discontinuities, thus increasing the strength of flange.
welding neck flange mainly used in the case of harsh conditions, such as pipeline thermal expansion or other load and so that the flange of the stress or stress changes over and over again, the pressure, temperature fluctuations in the pipeline or high temperature, high pressure and low temperature pipeline. welding neck flange is not easy to deformation, good sealing, wide application, nominal pressure PN1.0MPa~PN25.0MPa.
welding neck flange in accordance with the sealing surface types can be divided into: plane welding neck flange, surface process of welding neck flange, concave convex welding neck flange, tongue and groove surface flange, ring surface welding neck flange connection.
Source: Zhejiang Yaang Pipe Industry Co., Limited (www.yaang.com)