An improved displacement adjustment method for overlarge deformation of valve at the cryogenic temperatures

Abstract

Cryogenic valves are mostly designed at the room temperatures and served at the cryogenic temperatures. The wide temperature difference between design and service conditions causes the overlarge deformation of the valve stem structure, resulting in the cryogenic valve prone to leakage, stuck and other unsafety issues. In this study, an improved displacement adjustment (IDA) compensation method is proposed to solve the problem of size over-tolerance and shape deformation of the valve stem at the cryogenic temperatures. The shape of the valve stem is redesigned by combining IDA and the finite element method to meet its ideal service requirements under the cryogenic conditions. One of the features of the IDA method is to optimize the compensation direction by considering the angle change of normal vector on valve stem surface. Another is to improve the iteration efficiency by recognizing the compensation factor through the Lagrange interpolation algorithm. The simulation and experimental results show that the proposed compensation method can effectively reduce the size and shape deviation of the valve stem. Therefore, this study provides a new method to reduce the stem deviation at the cryogenic temperatures by the shape compensation, which has reference significance for the design of other low temperature components.