| 摘要 |
PURPOSE:To obtain a method for manufacturing a valve disc of a butterfly valve in which corrosion scarcely occurs, a lifetime is improved and liquid is not leaked by integrating an upper mold with a lower mold set with a valve stem die, casting fiber-reinforced resin liquid, then press-molding it. CONSTITUTION:A method for manufacturing a valve disc or a butterfly valve connectable to a valve stem comprises the steps of firstly forming a lower mold 80 with a circular bottom plate 81 and a lower peripheral side plate 82 extended from a peripheral edge of the plate 81 upward and forming two valve stem die insertion holes 85 of the plate 82. An upper mold 90 has an upper peripheral side plate 92 formed at an upper center with an introducing port 91. The method further comprises the steps of integrating the mold 90 having a fiber-reinforced resin layer 105 formed on a sealing part forming surface 95 of an inner surface of the plate 92 by hand lay-up laminating with the mold 80 in which a valve stem die 100 is set between the holes 85, then casting the liquid 106 in both the molds 80, 90 through the port 91, the press molding it through the port 91, then removing the die 100, and separating the molds 80, 90. |
