Study on the distortion prediction of focal plate

摘要

The focal plate is one of the most important components of the LAMOST , whose shape precision to be centripetal and spherical structure of multi-hole. The hole drilling distortion duing to residual stress becomes one of the striking problems. Studying on the distortion prediction, this paper adopts the finite element simulation based on the metal cutting principles. The distribution to the surface residual stress is achieved by building the FEM model using ANSYS .The influence of cutting depths on the distortion of the focal plate was investigated. With the confirmation of the final CMM test result, the deviation which compared the measuring point with the theoretical sphere is less than 0. 066mm.The result showed that the FEM analysis is an effective method which predicts the machining distortion of the focal plate.