Abstract: Common pump body fixing methods for rotary compressors include frame fixing, main bearing fixing and cylinder fixing. Among them, the cylinder fixing is relatively advantageous in terms of cost, but it is prone to deformation of the sliding vane groove after the welding of the lower casing in the assembly process. In order to solve the above problems, by establishing a thermo-solid coupling finite element simulation method, it is clear that the welding seam of the lower shell shrinks inward as a whole after cooling. The diameter of the cylinder (other parts except the welding point) is in contact, which destroys the original force mode of the cylinder and deteriorates the deformation of the cylinder vane groove. Simultaneously verified the reliability of the simulation model, and proposed an improvement plan for the outer diameter end face avoidance groove of the cylinder and the thickening of the lower shell, which significantly improved the deformation of the cylinder slide groove, reduced the defect rate of the production line, and ensured the smooth production of the production line.

Key words: Rotary compressor, Vane groove deformation, Cylinder fixed, Lower shell welding, Finite element