The Mechanism Of Bending-Torsional Coupling Vibration Stress Relief And The Choice Of Processing Parameters

The work piece would generate residual stress during the processing of produce. The residual stress will have many harmful influences on the performance of work piece. In order to decrease the negative effects of residual stress, eliminating the residual stress of work piece is an essential work. Vibration stress relief (VSR) is an effective measure of removing residual stress.VSR has many advantages like energy conservation efficient and environmental protection. Because of the natural frequency of high rigidity work piece is much higher than existing VSR equipment can provide, the equipment can’t reach the demand of resonance state and dynamic stress. The high rigidity work piece can’t use VSR to relief residual stress. If we can find a new mode of vibration that could reach the stress demand of VSR, let the high rigidity work piece can also use the way of VSR to decrease residual stress, the space of VSR would have largely expand.When rotor exist eccentricity, there will be coupled effect between bending vibratory and tensional vibration. This kind of coupled vibratory can also product resonance when the rotate speed and extrinsic motivation meet the condition. If this kind of vibration can be used in the VSR, let the work piece achieve resonance state in the way of bending-torsional coupling resonance, reach the stress demand of VSR, the problem of high stiffness work piece would be solved.In the face of the above situation, this paper put forward a new measure of VSR based on bending-torsion coupling theory. Firstly, a model of eccentric rotor with coupled bending and tensional vibrations was built and the vibration equation was solved by small parameter method. Then considering the forcing frequency and dynamic tress of the existing equipment can provide, the main resonance of bending- torsion coupling vibration stress relief was determined, and the mechanism of bending-torsion coupling vibration stress relief was put forward. Finally, a roll was used as rigidity work piece example, counting the additional torque bending-torsion coupling vibration stress relief need. The research work provided ideas and basis for the VSR of high rigidity work piece. The idiographic work is as follows:(1) The bending- torsion coupling vibration equation of eccentric rotor was built by Lagrange method. Fourier transform was made aim at coupling terms. The influence of motivation and coupling force was analysis. The request of bending torsion coupling vibration was conformed. The work above provide theory basis for the bending torsion coupling vibration stress relief.(2) Small parameter method was used to solve bending torsion coupling vibration equation and representation it as superposition of a serious simple harmonic vibration. The specific vibration mode was confirmed. Then compare the amplitude of vibration model and choice the main resonance vibration mode of bending torsion coupling vibration.(3) The theory of deflection of beam, strength and fatigue theory under the cyclic stress were used to calculate the need of excitation torque excitation frequency and rotate speed bending torsion coupling stress relief need. The mechanism of bending torsion coupling stress relief was explained from the point of stress.(4) A roller was used as a study target and dynamics simulation was made by Matlab. The frequency and amplitude was researched numerical simulation. The parameters of bending torsion coupling stress relief were calculated based on some specific points. The numerical calculation show that bending torsion coupling stress relief can preferable remove residual stress.