Electromagnetic Crimping on Threaded Surface: FEM Modelling, Validation and Effects of Pitch and Discharge Energy on Deformation in an Empirical Relation

TL;DR

This paper models electromagnetic crimping for tube joining using FEM, validates the model experimentally, and develops an empirical relation linking deformation to discharge energy and thread pitch.

Contribution

It introduces a non-coupled FEM simulation approach for electromagnetic crimping and derives an empirical relation to predict deformation based on process parameters.

Findings

Deformation increases with discharge energy.

Deformation increases with thread pitch.

Empirical relation accurately predicts deformation.

Abstract

Electromagnetic crimping is a high-velocity joining method to join highly conductive workpieces where a pulsed magnetic field is applied without any working medium or mechanical contact to deform the workpiece. This work explores tube-to-tube joining of Copper outer tube and Stainless steel threaded inner tube using electromagnetic crimping. A non-coupled simulation model is developed for the finite element analysis. ANSYS Maxwell package is used to obtain the magnetic field intensity, which is later converted to pressure using an analytical equation, and this pressure is applied to the two-tube working domain in ANSYS Explicit Dynamics. Numerical simulations are done for different combinations of discharge energies and pitches of the thread to analyse deformation, stress and strain. The converged finite element results are validated using experimental data. The amount of deformation is found to be proportional to discharge energy and the pitch of the thread used. An empirical relation is developed for the deformation as a function of discharge energy and pitch. The relation is able to predict the deformation for other discharge energies, which is later verified with ANSYS simulations.