Analysis and research for the fault of valve cone bolt in steam turbine governor valve

JIN Chang-sheng, FANG Yin, WANG Jun-wei

(Hangzhou Steam Turbine Co., LTD. Hangzhou 310022, China)

Abstract: Aiming at the problem of industrial steam turbine governor valve fault, leading to the turbine shutdown, the structural characteristics, the industrial steam turbine governor valve were analyzed and researched, the fault mechanism and the working environment were researched of the break and wear of the valve cone bolt, resulting the governor valve malfunction, the measures were presented to decrease the length of the valve cone bolt,increase the diameter of the bolt and improve the assembly technology of the valve, the model was established by the 3D software and the stress was analyzed by ANSYS software of improvement and improved vavle cone bolt. The results indicate that the plan decrease the alternating stress of the valve cone bolt,enhance the strength of the valve cone bolt, and improve the case of the relative displacement for the threads because of the uneven thermal expansion. Then combined with the practical fault case in NingXia petrochemical units and applied to the units, the experimental results show that the plan solves the valve cone bolt falfunction.

Key words: steam turbine; governor valve; valve cone bolt; fault analysis