How To Connect Flanges Of Hardware Parts?

Flange connections can be classified into five types: flat welded, butt welded, socket welded, loose sleeve, threaded. The first three types are described in detail as follows:
1. Flat welding: Only the outer layer is welded, no need to weld the inner layer. Generally used for medium and low pressure pipeline connection, nominal pressure is less than 2.5MPa. Flat welded flange has three sealing surfaces, namely smooth type, concave and convex type and tenon type, among which, smooth type is widely used, has the characteristics of cheap, cost-effective.
2. Butt welding: The inner and outer layers of flanges should be welded, which is generally used for medium and high pressure pipelines. The nominal pressure of pipelines is between 0.25 and 2.5MPa.
3. Socket welding: Generally used for pipe connection with diameter less than or equal to 40 mm.