Technology Study of Thin-walled Frame Used in XX Inertial Navigation System Casted by Differential Pressure Casting

摘要

Frame used in XX inertial navigation system has such characters as small scale, thin wall, complicated shape, etc. When it is casted by gravity casting, the defects such as shrinkage, porosity and blow holes are so many that the survival ratio is very low. In this paper, a new differential pressure casting method is designed to cast the frame by realizing self-hardening sand moulding, solving series of problems such as liquid rising pipe freezing and chemical composition being out of range, thus improving the quality of the cast.