Abstract: The reliability of the steam inlet regulating valve determines whether the steam turbine can operate for a long period of time or not, which in turn affects the output and the overall benefits of the company. This paper introduces the structural characteristics and fault causes of the control valve of the steam turbine driven by cracking gas compressor unit in certain chemical enterprise. It focuses on analyzing the adjustment methods and technical points of the inlet control valve. The results show that the use of this adjustment method can not only reduce the maintenance time, but also ensure the maintenance quality, which saves the cost for the device maintenance and provides strong guarantee for the stable operation of the device as well. This method is an innovation of the previous overhaul methods based on the familiarity with the working principles of machinery and instrument control. It can provide feasible implementation plan for the same industry in regulating gas valve overhaul, and provide reference for the improvement of the reliability of the valve beam in practical use.

Key words: steam turbine, regulating valve, adjustment method