The manufacturing method of pipe fittings – reducer
Reducer pipe fittings are of chemical pipe fittings used to connect two pipes of different diameters. It is divided into concentric reducer and eccentric reducer.
The roundness of the reducer should not be greater than 1% of the outer diameter of the corresponding end, and the allowable deviation is ±3mm. The material of reducer complies with SY/T5037, GB/T9711, GB/T8163, American standard ASTM A106/A53 GRB, API 5L, APT5CT, ASTM A105, ASTM A234, ASTM A106, DIN German standard and customer requirement standard.
Reducers are a kind of pipe fittings used for pipe diameter reduction. The commonly used forming process is reducing diameter pressing, expanding diameter pressing or reducing diameter plus expanding diameter pressing and stamping forming can also be used to reduce the diameter of certain specifications.
1. Diameter reduction/expansion forming
The reducing forming process of reducer is to put the tube blank with the same diameter as the big end of the reducing tube into the forming mold, press the tube along the axial direction of the tube blank, and make the metal move along the mold. cavity and shrinks into shape. According to the size of the reduced diameter of the reducer, it can be divided into one-time compression molding or multiple compression molding.
Diameter expansion forming is to use a tube blank that is smaller than the diameter of the large end of the pipe fitting with a different diameter and use an internal mold to expand the diameter along the inner diameter of the tube blank. The diameter expansion process mainly solves the problem that it is difficult to form a large-diameter reducer through diameter reduction. Sometimes, according to the needs of materials and product molding, the method of enlargement and reduction can be used at the same time.
In the process of reduction or expansion deformation, cold pressing or hot pressing is determined according to different materials and diameter changes. Normally, cold pressing should be used as much as possible, but due to severe work hardening caused by multiple diameter changes, wall thickness or alloy steel material, hot pressing should be used.
In addition to using steel pipes as raw materials for the production of different-diameter pipes, certain specifications of different-diameter pipes can also be produced by stamping steel plates. The shape of the die used for deep drawing is designed according to the size of the inner surface of the reducer, and the punched steel plate is punched and stretched through the die.