METHOD AND DEVICE FOR MANUFACTURING INNER AND OUTER DOUBLE TUBE

摘要

PROBLEM TO BE SOLVED: To manufacture an inner and outer double tube used for various kinds of heat insulating pipe such as a finisher pipe and an exhaust pipe in an exhaust system of an engine for an automobile easily at low cost. SOLUTION: In manufacturing the inner and outer double tube with round or ellipse cross section having turn back parts having U-shape cross section on at least one end side, a material tube 11 is arranged on an inner circumference side of a tubular core bar 20, and one end side of the material tube 11 is moved from the one end side of the tubular core bar 20 along an outer circumference side in order. Consequently, at least a part of the material tube 11 is reversed inside out to manufacture the inner outer double tube. COPYRIGHT: (C)2007,JPO&INPIT