METHOD AND APPARATUS FOR MANUFACTURING CORRUGATED TUBE WITH SMOOTH INNER SURFACE

摘要

PURPOSE:To obtain easily a tube with smooth inner circumference and corrugated outer circumference by a method wherein a resin tape supplied from one die is wound about special bodied of revolution to mold a corrugated special tube and a resin tape supplied from the other die equipped inside the spiral tube is stuck closely to the inside of said sprial tube. CONSTITUTION:The molten thermoplastic resin tape A supplied from one die 3 is wound about the circumference surface of a group of bodies of revolution 18 (arranged on the same circle) with spiral projections on the circumference surface along a spiral direction to mold an outer tube with a corrugated section and as this outer tube is transferring to the circumference surface of the group of bodies of revolution 20 (arranged on the same circle), the resin tape B supplied from the second die 4 is stuck closely to the inside of the transferred corrugated tube. Thus, the desired corrugated tube is obtained.