Pipe cold-rolling mill

摘要

The invention relates to rolling production. A pipe cold-rolling mill comprises a stand which has a housing with longitudinal guides rigidly fixed therein. In said guides a carriage is installed on a pair of backup rolls mounted in the housing. Said carriage is connected via a crank gear with a drive of the mill to effect the reciprocating movement of the carriage in said guides in the process of rolling a pipe. Said carriage also carries a pair of working rolls positioned at both sides of the axis of the pipe to be rolled. Said working rolls interact each with one of the two backup rolls and are, together with the latter, spring-actuated one with respect to the other. In such a case, said carriage is rigidly linked with a connecting rod of said crank gear which gear is accomplished so that during the working stroke of the carriage the shafts of all the rolls are positioned in a plane perpendicular to said longitudinal guides, whereas during the idle stroke of said carriage - in a plane inclined to them - the distance between the shafts of the backup rolls is bigger than during the working stroke of the carriage. At the beginning of the idle stroke of the carriage said working rolls are separated under the action of springs, while at the beginning of the working stroke they are brought together until contact is established with the surface of the pipe to be rolled. A mill of such a design is more reliable in operation, has a longer service life and has a greater production capacity than the known mills of the same type.