Copper or brass pipe with bending in the cold state, the molten resin is filled. Bending process is similar to that described above. Rosin after bending is smelted from the pipe ends, as at mid-heating pipes, filled with resin, the cleavage of her. Copper and brass tubes for bending in the cold able to anneal at a temperature of 600-700 C and cooled in air. Fillers for bending copper pipes in a cold resin and heated in – sand.
Fillers for the brass tubes are the same as that of a flexible copper tubes. Duralumin tube to a flexible annealed at 350 – 400 C and cooled in water. After this treatment, the tubes are bent well over two hours. With mass production of parts from tubes used hand-held Pipe-bending devices and beam bending, and bending large diameter pipes – special pipe bending machines and press. Recently, extensive use of flexible tube with a stretched piece and the heating currents high frequency. When bending the tubing is stretched preform is subjected to tensile stresses exceeding the yield strength of metal and then bend.
This process is carried out on the bending and rastyazhnyh machines with rotary table for Pipe bending planes, cars, marine and river vessels and other parts manufactured by this method have high strength. When bending pipes with heating by high frequency heating, bending and cooling occur sequentially and continuously in a special high-frequency setting, which consists of mechanical and electrical parts. The mechanical part of a machine for bending pipes, and electrical and electrical equipment consists of inducer. Installation allows bending pipes from 95 to 300 mm. The above method has several advantages: it provides a lower roundness Bends in pipes, high performance (4-5 times higher than the other way), the mechanization process. Are properly curved pipe, no dents, bulge and crease. The reasons for marriage in bending and straightening when bending metal marriage is most often seen in oblique bending and mechanical injuries treated surface as a result of improper marking or fixing the details in the grip up or down a road marking lines, as well as improper attacks. When you edit the main reasons for marriage are the dents, the marks of the hammer Hammer, Nick on the treated surface of the hammer. These causes are the result of a hammer, to whom there is a lively and Nick vyscherbiny, misuse attacks.