Research On The Law Of Influence Of Geometric Technology Parameters On Axis-Thrust Tube Bending Process

Axis-thrust tube bending process using local induction heating is one of the important forming technics of tube forming, and it has been widely used in many fields. If size and shape of a piece are fixed, the technology parameter mainly includes temperature field parameter, pushing velocity, additive moment, position of roller and the initial angel, and so on. However, the research has now been focused on the influence on forming process of tube of temperature field parameter, pushing velocity and additive moment. And research of influence on forming process of process parameter is a few. Whereas, research result has indicated that choosing reasonable geometric technology parameter is of vital important for obtaining eligible parts. Nowadays, the technology theory of axis-thrust tube bending has not been mature, so studying of axis-thrust tube bending, especially studying of geometric technology parameter, has theoretical and practical meaning.Taking the axis-thrust tube bending process, using local induction heating, supported by a pair of roller as research object, the paper mainly studies the moment distribution rule, under different geometrical process parameters, both in theoretical method and finite element simulation method. And there comes to the method of deciding the position of roller and the initial angel, and so on.The stress distribution form has been reasonably presumed again. Then, the force conditions of the tube bending process with one pair of supporting roller is analyzed, there comes to formulas of neutrosphere offset, pushing force, counterforce of roller exerts on tube, moment of cantilever area, and moment of deformed area, and so on. The model of flexibility of cantilever area, local flatting, and buckling under a pressure load have been presumed. And the influence on flexibility of cantilever of different roller position has been analyzed theoretically. Restricting the maximum flexibility according topractical needs, then the maximum position of roller can be decided.The process of axis-thrust tube bending using induction heating is simulated by Finite Element Method (FEM), and the loading of transient temperature has been solved. Comparing the results obtained from FEM with those obtained from theoretical calculation, there verifies the reasonability of theoretical calculation. For the local flatting problem of cross-section, that can be seemed as a problem of curve girder bending under outside force, is analyzed by FEM, which can not be easily calculated by theoretical method. And there comes to the result that both roller position and initial angel have little influence on cross-section flatting.