The invention discloses a centering roller with a compact structure. The centering roller comprises a small-opening hydraulic cylinder (1) and a large-opening hydraulic cylinder (4), which are movablyThe invention discloses a centering roller with a compact structure. The centering roller comprises a small-opening hydraulic cylinder (1) and a large-opening hydraulic cylinder (4), which are movably is fixedly connected with a second lower roller (10). The centering roller has compact structure, little occupied area and small occupied space, lowers cost, saves equipment space, and meets the p11) is fixedly connected with a second lower roller (10). The centering roller has compact structure, little occupied area and small occupied space, lowers cost, saves equipment space, and meets the production requirement by using the space as little as possible.roduction requirement by using the space as little as possible.connected through a connecting rod (3). The centering roller is characterized in that the bottom end of the small-opening hydraulic cylinder (1) is provided with a positioning block (2), the large-op connected through a connecting rod (3). The centering roller is characterized in that the bottom end of the small-opening hydraulic cylinder (1) is provided with a positioning block (2), the large-opening hydraulic cylinder (4) is connected with one end of an upper roller frame (5), a gear on the upper roller frame (5) is meshed with a gear on a first lower roller frame (6), the other end of theening hydraulic cylinder (4) is connected with one end of an upper roller frame (5), a gear on the upper roller frame (5) is meshed with a gear on a first lower roller frame (6), the other end of theupper roller frame (5) is fixedly connected with an upper roller (7), the first lower roller frame (6) is fixedly connected with a first lower roller (8), the lower part of the first lower roller framupper roller frame (5) is fixedly connected with an upper roller (7), the first lower roller frame (6) is fixedly connected with a first lower roller (8), the lower part of the first lower roller frame (6) is connected with one end of a pull rod (9), the other end of the pull rod (9) is connected with one end of a second lower roller frame (11), and the other end of the second lower roller frame (e (6) is connected with one end of a pull rod (9), the other end of the pull rod (9) is connected with one end of a second lower roller frame (11), and the other end of the second lower roller frame (11)