Heat treatment of mining round link chainis is the key to the product quality and production efficiency. But because the control method and stability and other reasons, the medium frequency induction heating system used at presentdomestic chain in mining circular heat treatment often do not meet process requirements. The design determines the high quality chain before quenchingthe most reasonable temperature in deep analysis on the quenching process. The non-contact infrared sensor quenching temperature on the chain for real-time detection, integral separation PID algorithm, using PLC as the control core, control of the intermediate frequency power supply control module uses the D/A module, A/D module to collect feedback of the system, and through the touch screen to set the parameters of the system. The final realization of high precisionto is the closed-loop control of quenching process. In view of the complex environment of the industrial site stability analysis of the temperature control system, from the actual results of the system was put into use in intermediate frequency induction heating equipment temperature control accuracy is high and the operation is simple and convenient, friendly man-machine interface, the long-term stable and reliable operation.