Electrical engineering & Electromechanics (Apr 2015)
AN ANALYSIS OF THE ELECTROMAGNETIC PROCESSES IN THE INDUCTOR SYSTEM – TOOL OF THE STRAIGHTENING OF CAR BODIES
Abstract
Introduction. One of the promising directions of electromagnetic forming (EMF) is a contactless magnetic-pulse straightening of the automobile bodies. The efficiency and the quality of the straightening depend on design and operating principle of the straightening tool. In the modern technique of EMF a large number of the tools - inductor systems (IS) is used in different configurations with uneven distribution forces on the treatment object that in turn does not meet the needs of the effective process of straightening. There appears the urgent necessity to create IS with high uniformity of the induced field and a high concentration of attracting forces in the working area of the tool. The most effective IS are the Inductor Systems with an Attracting Screen (ISAS). One of the most important considerations when choosing a particular design ISAS is the study of the electrodynamics processes with definition of excited loads. The nature and the course of the electrodynamics processes in accordance with design features determine the effectiveness and the efficiency of the ISAS. Therefore, in ISAS an additional coil for the concentration of the attracting forces in the working area should be entered. Purpose. The numerical analysis of the induced fields and the currents in the experimental models of ISAS with an additional coil was made. Methodology. In the idealization of the «extremely low» frequencies of existing fields, there were received rated dependences for density of the induced currents and distributed attracting force in ISAS and the external additional coil, through the use of the calculated model in the cylindrical coordinate system. Results. Insertion of the additional coil placed over the accessory screen allows to concentrate and increase the amplitude of the attracting forces in the central part of the working area of the inductor system. Practical value. 1. Numerical analysis of fields and currents in experimental models of Induction Systems with Attracting Screen (ISAS) and additional coil, designed to align the metal coatings of vehicles was made. 2. It is shown that if in ISAS they insert additional coil placed over the accessory screen significantly increases the amplitude of excited forces of attraction. 3. It is shown that the parallel connection of the primary and additional coils in ISAS allows to concentrate the forces of attraction in the centre of the working area of the tool for straightening automobile bodies.
