| 摘要 |
PURPOSE:To obtain a two-layered pipe having a desired layer thickness by providing gate parts for holding the molten metals for the inside and outside layers at a specified level and regulating the layer thickness and a storage chamber for the excess molten metal at the inside end of a casting mold and casting the molten metals for the inside and outside layers in excess of the amt. conforming to the required layer thickness. CONSTITUTION:A casting mold 1 is rotated around an axial center l and a molten metal M1 for the outside layer is cast through a casting hole 21 and a spout 8 into a casting part A. A molten metal cylinder is formed on the inside surface of the part A by centrifugal force and at the same time the excess molten metal regulated to the projecting height of the 1st gate part 4 is streamed into the 1st storage chamber 5. When the molten metal M2 for the inside layer is cast into the part A in excess of the amt. conforming to the prescribed thickness of the inside layer after solidification of the molten metal cylinder for the outside layer, the molten metal cylinder for the inside layer is formed along the inside circumferential surface of the outside layer and the excess amt. overflows from the gate part 6 and is stored in the 2nd storage chamber 7. The two-layered pipe having the exact layer thickness is thus obtd. |
