A. reducing forming/hole enlargement
Reducer reducing forming technology is will be equal and reducer big end diameter of tube rounds into the forming mould, through along the axial direction of tube billet, shrink along the cavity movement and metal forming. According to the size of the reducer reducer, divided into the one of pressing or more press forming.
Forming hole diameter is less than reducer big end diameter of the tube billet, used in die forming along the tube billet diameter hole enlargement. Hole enlargement technology mainly to solve the reducer in the variable diameter is larger not easily by reducing forming, sometimes according to the requirements of the materials and products forming, expanding and reducing method of combination.
In the process of reducing or expanding deformation, according to different materials and variable diameter, determination by cold pressing and hot pressing. Under normal circumstances, as far as possible by cold pressing, but the multiple variable diameter and cause serious work hardening of the thick or alloy steel, wall thickness of materials appropriate USES hot pressing.
B. stamping
In addition to the use of steel tube as raw material to produce reducer, the part of the specifications of the reducer can also be used steel plate stamping forming technology is adopted to improve the production. Drawing die shapes used by reference to reducing tube surface size design, use after blanking punching die, stamping steel stretch forming.
The stress distribution and deformation characteristics:
(1) the inner pressure function similarly hereinafter heart reducer an area about the size of the pressure difference between the bending moment caused by big end is relatively open, small end relative shrinkage phenomenon;
(2) the internal pressure under the action of eccentric reducer in central eccentric side inside the big end surface and eccentric side to the outer ring stress is the largest.
Source: Zhejiang Yaang Pipe Industry Co., Limited (www.yaang.com)
