The production department of marine parts and components is responsible for the production control of the whole process of castings from modeling, core making → box closing → electric furnace smelting → pouring → unpacking and cleaning → heat treatment → welding repair → post weld heat treatment → finished castings. In addition, it is required that the non perpendicularity between the upper end face of the part and the axis of the middle part shall not exceed 0.04 mm. Based on this, certain measures shall be taken to support and position the upper and lower parts of the part during the investment casting process. The surface and interior of all castings shall be free of cracks, shrinkage cavities, air holes, cold shuts, scabs and other defects. The surface roughness shall comply with the requirements of the approved drawings.
