Socket welding flanges are called SW flanges, and the basic shape of socket flanges is the same as that of flat welding flanges with necks.
There is a socket in the inner hole of the flange, and the pipe is inserted into the socket and welded. Weld the weld seam ring on the back of the flange. The gap between the socket flange and the grass groove is prone to corrosion, and if it is welded internally, corrosion can be avoided. The fatigue strength of the socket flange welded on the inner and outer sides is 5% higher than that of the flat welded flange, and the static strength is the same. When using this socket end flange, its inner diameter must match the inner diameter of the pipeline. Socket flanges are only suitable for pipes with a nominal diameter of 50 or smaller.
Shape: Convex surface (RF), Convex convex surface (MFM), Tongue surface (TG), Circular connecting surface (RJ)
Application scope: Boiler and pressure vessel, petroleum, chemical, shipbuilding, pharmaceutical, metallurgical, mechanical and elbow stamping industries.
Socket welding flanges are usually used in pipelines with PN ≤ 10.0 MPa and DN ≤ 50.
Advantages and disadvantages of socket welding flanges and butt welding:
Socket welding is usually used for small pipes with a diameter less than DN40 and is more economical. Butt welding is usually used for parts above DN40. Socket welding is the process of first inserting the socket and then welding it (for example, there is a flange called a socket flange, which is a convex welding flange that is connected to other parts (such as valves). The connection form of butt welding flange and pipeline welding, socket welding usually involves inserting the pipeline into the flange and welding it, while butt welding uses the butt welding flange to weld the pipeline to the mating surface. Although X-ray inspection is not possible, butt welding is acceptable. Therefore, it is recommended to use butt welding flanges to improve the requirements for welding inspection
Butt welding usually requires higher requirements than socket welding and post welding. The quality is also good, but the testing methods are relatively strict. Butt welding requires X-ray inspection. Socket welding can be used for magnetic particle or permeability testing (carbon powder, penetrating carbon steel), such as stainless steel). If the fluid in the pipeline does not have high requirements for welding, it is recommended to use socket welding. The connection types for easy testing are mainly small diameter valves and pipelines, used for pipe joints and pipeline welding. Small diameter pipelines are usually thin walled, Easy to cause edge misalignment and erosion, and difficult to butt weld, suitable for socket welding and socket mouth.
Welding sockets are often used under high pressure due to their reinforcement effect, but socket welding also has drawbacks. Firstly, the stress state after welding is poor, making it difficult to completely melt. The trend is that there are gaps in pipeline systems, making them unsuitable for medium sensitive to crevice corrosion and pipeline systems with high cleanliness requirements; Use socket welding; There are also ultra-high pressure pipelines. Even in small diameter pipelines, there is a large wall thickness and socket welding can be avoided as much as possible through butt welding.
Post time: Apr-25-2023
