摘要 |
PROBLEM TO BE SOLVED: To remove sand in a cylinder from a cylindrical cast product 1 without disassembling a frame.SOLUTION: A sand mold 3 including a cast product 1 is configured so that an axial direction of the cast product is vertical, and a drill is rotated and fallen for piercing holes 7 passing inside of a cylinder of the cast product 1 on the sand mold 3, and impact rods 14 coupled to rotation shafts 12 via flexible joints 13 are inserted into the holes 7 of the sand mold 3, and when the rotation shafts 12 are rotated, the flexible joints 13 are bent and the impact joints are shaken, thereby sand in the cylinder of the cast product 1 is broken. |