| 摘要 |
PURPOSE:To bond a closing material firmly in any condition and at all times by a method wherein a passage closing material is fitted to a mandrel tip and the passage closing material is molded integrally with the shoulder part and the throat part of the tube and then the passage closing material and the bonded part between the shoulder part and the oral part are reheat-treated. CONSTITUTION:A passage closing material 2 composed of a closing part (a) and an expanding part (b) made of laminated material is fitted to the tip of a mandrel 1 and a barrel part 3 of laminated material covers the circumference. The tip part of the mandrel 3 is inserted into the cavity 5 of a split mold 4, synthetic resin 6 is supplied into the cavity 5 and hardened, and the throat part and the shoulder part are molded integrally with the barrel part 3 and the passage closing material 2. After synthetic resin is hardened, the molded piece is taken out of the split mold 4, and the throat part to the shoulder part of the piece is inserted into a high frequency coil 8 and reheated by high frequency induction heating. In this way, the passage closing material is bonded surely and can be broken through positively when it is used. |
