| 摘要 |
PROBLEM TO BE SOLVED: To provide a resin ball for a ball valve capable of reducing its manufacturing cost and to provide its manufacturing method. SOLUTION: A spherical surface 18 corresponding to a virtual spherical surface is molded on the surface of a resin ball 10 by the inner face of the spherical space of a die, and a band-like recess section 16 is formed on the surface of the resin ball 10 by a recess forming section provided in the spherical space. The recess section 16 is formed in a band shape along the parting line of the die. Even if a burr B is generated along the parting line, the burr B is arranged at the recess section 16 within the virtual spherical surface. Even when the resin ball 10 is assembled to a valve without being deburred and is rotated in the held state by both packings, the burr B is not hooked on a holding curved surface.
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