To bend tubing which, on heating becomes malleable, an inner sleeve (3) which can expand to a given size is inserted into the tube (1) to be bent before bending. The inner sleeve (3) is filled with a pressure medium so that it is pressed fully at the inner surface of the tube (1) to be bent, and then the line of the tube is shaped by bending as required. The inner sleeve (3) is a hose which can be expanded to a given size, with a covering (4) of a woven or braided material, to carry the pressure medium such as air, water, steam or oil under pressure in a steady feed. The pressure medium can also be heated to transfer heat to the tube (1).
展开▼
