Analytical Design of a Novel Clamp-On Type Actuator Coil for Magnetic Pulse Forming of Tubular Structures

Abstract

Electromagnetic forming of tubular workpieces using a pulsed power source is gaining acceptance in the non-conventional metal forming area. It finds extensive use in various industries for metal joining, electromagnetic crimping of wires, tube bulging for manufacturing of automotive parts, etc. This paper describes an analytical design and electromagnetic analysis of a novel clamp-on type uniform pressure electromagnetic actuator that works based on the primary induced currents. A fast analytical method has been developed and used for solving the electromagnetic(EM) fields instead of the conventional coupled numerical models based on Finite Element Method(FEM) technique. The agile manufacturing of the workpieces requires the workpiece assembly to be easily removed and replaced. However, the finished assembly is such that it is impractical to remove it out of the conventional helical actuator in most of the industrial applications. The designed actuator offers a substantial improvement over the conventional helical actuators in terms of flexibility of operation, reduced stress on the coil, reusability, robustness, and a uniform pressure profile on the workpiece. In addition, the paper also identifies important process parameters involved in the novel actuator design. It also develops an analytical model to compare the performance of the novel proposed actuator with a conventional helical actuator for a tube deformation process.