Research Of Shearing Method Based On Pulsed High Magnetic Field

With the development of economy and progress in science and technology, steel output is increasing quickly. Because the shear machine is one of important equipment in steel industry, the demand is also growing significantly. Cutting speed of existing mechanical and hydraulic shearing machines is relatively slow, due to unreasonable shear clearance parameters and bluntness of blade, the sheared sheet metal is easy to cause defects such as edges, burrs and folds. Shearing method based on pulsed high magnetic field has characteristics of high electromagnetic force energy density, fast shearing speed, flexible and controllable shearing force, which can significantly improve the quality of sheet metal, and it will have a good application prospect in the metal shearing and processing field.First of all, this paper discussed the basic principle of pulsed electromagnetic shearing method, from the time and space distribution of the magnetic field, generation of electromagnetic force to analyze the electromagnetic coupling principle between coil and driving board. Based on the analyses above and combining with existing shear devices, two kinds of simple and direct transmission suitable for high-speed electromagnetic shearing were put forward. Then the shear process and the section of metal sheet was studied and analyzed.Secondly, this paper analyzed the multi-physics fields coupling processes of electromagnetic shearing including circuit, magnetic field, temperature field and structure field. Two ways to process movement of the driving board applicable for FEM were put forward. This paper also built a complete 2-D FEM numerical model of electromagnetic shearing with COMSOL Multiphysics software.Thirdly, the electromagnetic system of the shearing prototype was analyzed and designed from the power supply system, shape and mechanical analysis of the driving coil. And also the mechanical structure of the prototype was designed from transmission structure, fuselage structure and auxiliary equipment. This designed experimental prototype can satisfy the requirements of shear capacity and mechanical strength.Finally, some pulsed electromagnetic shearing experiments were researched, including study and analysis of influence on shearing effect with different shear modes, discharge voltages, shear clearance choices, and comparison with the traditional hydraulic shearing method. The result showed that the quality of section with pulse electromagnetic shearing was much better than that with hydraulic shearing.