a machine for bending and straightening metal sheets and strips.
Sheet-bending machines with a rotary bending beam are designed for cold linear bending to produce parts of various shapes, as well as pipes on mandrels; to form flanges and closed contours; and for straightening sheet material. A turning beam and a bending beam are mounted on the machine frame. Bending is accomplished by rotating the bending beam. The turning beam holds the part in place and may be positioned as required by the thickness of the article and the bending radius. The drive of such machines may be mechanical or hydraulic. Machines of this type are used for bending sheets 0.8–5.0 mm thick.
Rotary-roll bending machines are designed for bending and straightening parts of boilers, high-pressure vessels, and converters, as well as pipes with diameters exceeding 400 mm. Articles are formed in such machines during the simultaneous passage of the sheet stock between the bending rolls and its lateral bending. The rolls are usually mounted horizontally. Machines are produced with three rolls, which may be arranged symmetrically or asymmetrically, or with four rolls. Roll bending machines are used for cold or hot bending of stock 1–150 mm thick (plate thickness, more than 50 mm); the speed of bending is 3–8 m/min.
REFERENCEMoshnin, E. N. Gibka i pravka na rotatsionnykh mashinakh, 2nd ed. Moscow, 1967.
O. A. SOLODUKHO