GB912645A - Method and apparatus for elongating metal bodies - Google Patents

Abstract

912,645. Stretching; rolling. GENERAL ELECTRIC CO. April 19, 1960 [May 6, 1959], No. 13669/60. Class 83 (4). A method of increasing the length of an elongated body, such as sheet, strip, wire, rod or tube, and reducing its thickness is characterized by subjecting successive portions of the length of the body to cyclic plastic strain, simultaneously subjecting the same successive portions of the body to tension stress insufficient of itself to produce plastic elongation of said body, and simultaneously also subjecting the same successive portions of said body to pressure sufficient only in combination with the cyclic plastic strain and the tension stress to reduce the thickness of the body. Strip S from a reel 10 passes through two sets of processing rolls 13, 14, 15 to a reel 12, tension being applied to the strip by differential torque or angular velocity of the reels 10, 12. The cyclic plastic strain is produced by the changing of direction as it passes round the rolls 13 and the pressure is applied by the contact rolls 14, 15 against the rolls 13. The bending rolls 13 may be floating and the rolls 14, 15 fixed in position or, as shown in Fig. 3, the bending rolls 13 fixed in position and the rolls 14, 15 carried by frames 17 pivoted to a lever 19 rocked about a pivot 20 by a weighted lever 26 to adjust the pressure of the rolls 14, 15. The strip may be passed first through the machine from the reel 10 to the reel 12 then back from the reel 12 to the reel 10. In another embodiment, Fig. 7, reels 10, 12 (not shown), apply the tension and laminated plates 31, 32 vertically moved by oscillating plungers apply the pressure and, as a result of the transverse displacement, the cyclic plastic strain. In a further embodiment, Fig. 9a, the tension is again applied by reels 10, 12 (not shown), the pressure by rolls 42, 43 and the cyclic plastic strain by heating the strip between the rolls in a furnace 40. In another embodiment, Fig. 10, the cyclic plastic strain is applied by twisting and untwisting the strip as it is pulled through a die or twisting mill, pressure being applied by rolls. In a further embodiment, Fig. 11, the cyclic plastic strain is produced by heating by the passage of an electric current, rolls 59, 60 applying the pressure.