| 摘要 |
PURPOSE:To prevent generation of eccentricity in a covering synthetic resin layer, by performing clamping and opening of a mold smoothly by moving a molding core along an inclined face of an outer mold and fitting cores to end parts of a metal pipe by pressing with springs. CONSTITUTION:When an elbow joint of a metal pipe P is covered with a synthetic resin layer, both end parts of the metal pipe P are fitted to cores 1, 1' and suspended in a molding cavity. One core 1 is attached in a concavity 61 of a moving mold 6 and a coil spring 5 prepared in the concavity 61 pushes a back of the core 1, also the core 1 is connected to the moving mold 6 via a bolt 4. Another core 1' is attached in a concavity 21 of a molding core 2 and connected to the molding core 2 via the coil spring 5' prepared in the concavity 21 and the bolt 4'. The molding core 2 is constituted half split like and a cavity surrounding the cores 1, 1' and the metal pipe P is provided on its parting face. An inclined face 23 coinciding with an inclined face 32 of an outer mold 3 is provided on an outside face of the mold core 2. |
