| 摘要 |
PURPOSE:To provide a heat retaining cover for piping which can be processed easily, can be applied to various shapes of pipe, can be manufactured easily by integral molding with the same material, and a method for manufacturing it. CONSTITUTION:In a manufacturing method of a heat retaining cover A for piping whose inside shape conforms with an outline of a pipeline P whose heat is to be retained, an expansion molding mold wherein the heat retaining cover A has a two-piece structure of two bases 1, 1 and cavities relating to the pair of bases 1, 1 are also provided is used. The expansion molding mold is filled with pre-expanding beads of polyolefin resin. Thereafter, the inside of the expansion molding mold in a clamped state is heated. Then, molding expansion of the bases 1 is done by fusion among the pre-expanding beads. On the other hand, a slide plate arranged on a core mold is lowered and the fusing layer of the pre-expanding beads arranged between the cavities relating to the bases 1, 1 is compressed into a thin skin, so that a hinge 2 to be connected to both bases is formed. |
