APPARATUS FOR MANUFACTURING OF DUPLEX PIPE AND THE MANUFACTURING METHOD THEREBY

摘要

The present invention relates to a double pipe manufacturing device and a manufacturing method thereof and more specifically, to a device for expanding and joining a second pipe inserted into a first pipe. The double pipe manufacturing device according to the present invention includes a pipe expanding unit which expands the ends of the first and second pipes; a pipe expanding plug which has an outer diameter larger than the inner diameter of the second pipe and which is inserted via the expanded ends; a tension bar which is extended from one end of the pipe expanding plug and which fixates the pipe expanding plug during extension; an inlet unit pressing the ends of the expanded first and second pipes after inserting the pipe expanding unit; and an extending unit holding and extending the pressed ends. The present invention can easily manufacture a double pipe proper to the purposes such as strengthening corrosion resistance and strength via a mechanical pipe expanding method and a double pipe having excellent size precision and an excellent joining force joining the inner and outer pipes by joining the inner and outer pipes by expansion and adjusting the inner and outer diameters of the double pipe using the pipe expanding plug and a die unit.