Neck butt welding flange, also known as high neck flange, neck butt welding flange is that there is a long and inclined high neck from the welding place between the flange and the pipe to the flange, and the wall thickness of this high neck is along the height. The direction gradually transitions to the wall thickness, improving the discontinuity of the stress and thus increasing the flange strength. Butt welding flanges with necks are mainly used in the occasions where the working conditions are relatively harsh, such as the occasions where the thermal expansion of the pipeline or other loads cause the flange to be subjected to large stress or repeated stress changes; pipelines with large fluctuations in pressure and temperature or high temperature, High pressure and subzero low temperature pipeline.
The butt welding flange with neck is not easy to deform, has good sealing, is widely used, has corresponding rigidity and elasticity requirements and reasonable butt welding thinning transition, the distance between the welding port and the joint surface is large, and the joint surface is free from welding temperature deformation. The complex trumpet-shaped body structure is suitable for pipelines with large fluctuations in pressure or temperature or pipelines with high temperature, high pressure and low temperature. It is generally used for the connection of pipelines and valves with a PN greater than 2.5MPa; on pipelines of explosive media.
