The necking forming method of large-caliber pipe fitting reducer

　　The necking forming method of large-caliber pipe fitting reducer is to put the pipe blank equal to the diameter of the pipe into the forming die, and then use the die to stamp along the direction of the pipe blank to ensure that the metal can move along the direction of the cavity film and ensure necking forming. In the Necking Process of large-caliber Concentric Pipe Fitting Reducer, because the diameters of the two sides are not equal, so it can be processed by one-time compression molding, but also can be processed by multiple compression molding.

　　The large-caliber pipe fitting reducer is a kind of connecting pipe for different caliber of pipes. Forming process, welding and expanding pressing, shrinkage and expanding pressing are usually adopted, and stamping can also be used for large-caliber pipe fitting reducer of some specifications.