Abstract: A monitoring system of vacuum low-pressure carburizing upper computer was designed based on Kingview 6.55 software. Through modbus communication between Kingview software and Yamatake instrument DCP31 and using the 2-DOF PID function of the instrument, real-time PID correction was carried out to ensure the accuracy of temperature control. Variables in carburizing process, such as flow control of C₂H₂and NH₃ and N₂, carburizing diffusion time, pulse number, holding time and quenching mode, were solidified into formulation form for users to call and modify. The design and application of this software platform reduce the mis-operation and complexity of the operators, and greatly improve the heat treatment quality of low pressure carburizing.

Key words: vacuum low-pressure carburizing furnace, temperature control, Kingview 6.55, 2-DOF PID, DCP31