Predicting the Effect of Field Shaper in Electromagnetic Welding Using FEM

Abstract

The research work presents a 3D numerical simulation to predict the distribution of magnetic field and pressure in the desired region of the tubular jobs using coils with and without field shapers in electromagnetic welding (EMW). For finite element (FE) simulation, single-turn (ST) and multi-turn (MT) (disk type) coils are considered to analyze the effects of field shapers with varying material combinations in ANSYS MAXWELL environment. The change in magnetic field distribution on the outer peripheral region of the flyer tube along axial direction with and without field shaper is graphically shown and compared. Also, variation of magnetic pressure on the flyer tube with respect to increasing voltage and time is compared individually for various material combinations of ST/MT coil and field shaper. Results show that in welding simulation (FE) using single-turn Cu and SS coils with field shapers of Be, Nb and Ta, the magnetic pressure increases by 34, 12 and 11% and 35, 12 and 11%, respectively, as compared to the coil with no field shaper. In case of multi-turn SS coil with Cu and Be field shapers, the magnetic pressure increases by 16 and 10%, respectively. The novelty of the work is the proper guideline to select the material combinations for ST/MT coils and field shapers and positioning of work pieces inside the coil in order to achieve maximum utilization of input energy in EMW system.