| 摘要 |
PURPOSE:To facilitate manufacturing while using a simple mold, in molding a drain measure having a receiving port part provided with an undercuit part, by forming a preformed body having a front receiving port part having no undercut part by injection molding and subjecting said receiving port part to expansion molding. CONSTITUTION:In manufacturing a drain measure consisting of an insertion port part 11, a receiving port part 12 and an inspection cylinder receiving port part 13 and having a packing ring mounting groove 12A formed to the receiving port part 12 thereof as an undercut part, at first, a preformed body 1A having a front receiving port part having no undercut part is molded by injection molding. Next, the front receiving port part 12C of the preformed body 1A is heated and softened to be received in an expansion mold (a) having the cross- sectional shape corresponding to the outer surface shape of the receiving port part 12 and a plug 5 and a cock body 6 are inserted in the front receiving port part 12C in a close contact state. Then, the receiving port part 12 is formed by expansion molding by supplying high pressure air from the air feed pipe 8 connected to the air feed port 7A of the plug 7 to form the drain measure 1. |
