APPARATUS FOR SIZING AND STRAIGHTENING END PORTIONS OF LARGE-DIAMETER TUBES Russian patent published in 2004 - IPC

FIELD: plastic metal working, namely sizing and straightening end portions of large-diameter tubes after heat treatment. SUBSTANCE: apparatus includes two three-roller and two one-roller heads. Each three-roller head has two outer sizing rollers and one inner sizing roller with parallel axes and motion drive units. Each one-roller head has one sizing roller and individual drive for moving by tube diameter. Apparatus is provided with rotary platform having guides mounted on rotary shaft normally relative to straightening axis. Three- roller heads are arranged diametrically relative to straightening axis in guides of platforms by means of frames. One-roller heads are mounted between three-roller heads diametrically relative to straightening axis also in guides of platform with use of frames. EFFECT: enhanced quality of sizing ad straightening large-diameter tubes, reduced out-of-roundness of tubes. 3 cl, 4 dwg