| 摘要 |
PURPOSE:To manufacture a corrugated pipe having a uniform wall thickness at a low cost, by feeding a cord material for corrugation forming endlessly in advance before supplying a semi-molten belt blank material on rollers arranged on the outer peripheral face of a mandrel and winding it helically. CONSTITUTION:A holder 3 is fixed and a mandrel 2 is rotated, and rollers 4...4 rotate (A guide part 3a at an end of a holding part 3 is separated from the holding part 3 to prevent sliding of a cord material). An endless cord material 9 for corrugation forming is fed on rollers 4...4 continuously in advance before a semi-molten belt blank material 13 is supplied from a supplying apparatus 14. Then, a semi-molten belt blank material 13 is supplied on them and a concave and convex corrugated pipe is formed. |
