METHOD OF HELICALLY CORRUGATING TUBE

摘要

METHOD OF MAKING A HELICALLY CORRUGATED TUBE A helically corrugated tube with improved heat transfer characteristics is made by twisting a deformable tube of circular cross section and at the same time moving the ends of the tube axially relative to one another. First the tube is twisted while the axial ends of the tube are moved relatively toward each other to cause helical corrugations to develop progressively along the tube. When the corrugations have been formed, the twisting and moving of the ends of the tube are terminated and then the tube is reverse twisted and axially stretched to a length greater than the length of the original tube. The resulting tube is corrugated and longer than the original tube, and has improved heat transfer and fluid flow characteristics.