| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a method for manufacturing a synthetic resin pipe of constant outer diameter, roundness and the like by a simple control method and a device, and also provide a cooling water tank thereof. SOLUTION: A vacuum cooling section 31 is provided in a cooling water tank 3, and a pipeline 314 for circulating cooling water is provided in the vacuum cooling section 31, while a heat exchanger 4 is set on the way of the pipeline 314, and a refrigerator 5 for feeding a refrigerant is connected with the heat exchanger 4 to keep the cooling water circulating in the vacuum cooling section 31 at a given temperature, and the outer peripheral face of a synthetic pipe P passing through the vacuum cooling section 31 is cooled by the cooling water while providing the expansion force in the diameter direction on the outer peripheral face. A synthetic resin pipe of constant outer diameter, roundness and the like can be manufactured by the above arrangement.</p> |
