| 摘要 |
PROBLEM TO BE SOLVED: To provide a new molding method for an elbow pipe due to a resin pipe for supplying water or hot water. SOLUTION: A crystalline resin is melted to be extruded as a pipe having a predetermined diameter and this pipe is cooled to form a resin pipe. After cooling, the resin pipe is wound around a square pillar having predetermined angles at its corners to be held until the resin is crystallized. Subsequently, the resin pipe is cut at the corners of the square pillar to mold the elbow pipe. In the drawing, a numeral 1 denotes the resin material; numerals 2 and 3, resin pipes; a numeral 10, the elbow pipe; A, a hopper; B, an extruder; C, a heater; D, a die; E, a water tank; F, the square pillar; and R, the curved parts of the corner parts of the square pillar. |
