The Research Of Finished-rolled Screw-thread Steel Bars Continuous Induction Heat Treatment And Deformation Control

Finish-rolled screw-thread steel bar is widely used in high-speed rail, bridges and high buildings. It is indispensable for national defense modernization. This topic mainly study its materials and continuous induction heat treatment process, and make sure the material of PSB930 and PSB1080 finish-rolled screw-thread steel bar is 40Si2MnV. Through the finite element method to simulate the induction heat treatment, determined the continuous induction heat treatment process for 500℃tempering after 930℃spray quenching, and after trial production verification.Finish-rolled screw-thread steel bar straightness request less than lmm/m. Deformation is caused by hardening organization stress and thermal stress. Then it require the cooling process control and deformation control of the spray quenching institutions. This article through the analysis and establishing quenching temperature field and stress field of the finite element model. And studied the influence of parameters on the uniform temperature quenching deformation. Through the experiment measured the temperature change curves of the different water flow rates and angles. Then surface heat transfer coefficient is analyzed by the method of inverse heat transfer method. Got the relationship between deformation and heat exchange conditions, and selected reasonable quenching injection pressure, flow and distribution state by adjusting quench equipment. It is guaranteed that the high strength products in accord with deformation standard, and it has got a good application in the production.