Study On Structural Parameters Of Spiral Groove Field Shaper In Electromagnetic Reducing Pipe Fittings

The electromagnetic shrinkage of pipe fittings is one of the high-energy forming techniques for processing metal pipe fittings by pulsed electromagnetic force.The reducing tooling consists of a clamp,an inductor coil and a field shaper.Among them,the field shaper is the core component in the reduction tooling.In order to prolong the service life of the coil and improve the energy utilization efficiency,the structural parameters of the filed shaper have an extremely important influence on the forming performance.Compared with traditional structures such as tapered field shaper and stepped field shaper,the spiral groove field shaper has higher energy utilization efficiency and longer service life of the corresponding coil,the influence of the structural parameters of the spiral groove field shaper on the forming performance of the pipe fittings is deeply studied,the establishment of the optimization process of structural parameters is of great significance for the design of pipe fittings.Based on the principle of electromagnetics and finite element theory,the finite element analysis software are used to simulate the deformation of aluminum alloy pipe fittings under different magnetic structure parameters,the influence of the ratio of inner and outer diameter D/d,total height H,inner shoulder height h and inductance coil number N on the diameter reduction of aluminum alloy pipe fittings are analyzed,the characteristics of tapered field shaper,stepped field shaper and spiral groove field shaper are analyzed and compared,the superiority of the spiral groove field shaper in the process of reducing the diameter of the metal pipe is determined.Finally,based on the results of finite element simulation analysis,the structure of the spiral groove field shaper and related supporting tools are designed,the diameter reduction experiments are carried out on aluminum alloy pipe fittings under different discharge voltages.The experimental results show that the maximum radial deformation and deformation distribution of the pipe fittings obtained by finite element simulation and experiment are not more than 15%,which indicates the correctness of the simulation process and the reliability of the results.