Finn pass forming device for forming seam welded steel pipes and roller device available for forming seam welded steel pipes of a plurality of sizes

摘要

In the fin pass forming apparatus, the fin roller is split in two symmetrically with respect to the center line of the flow direction of a steel pipe to be formed, and a plurality of side rollers are arranged on a section perpendicular to the flow direction of the steel pipe. At least one fin roller stand is mixed in a group of roller stands including a cluster mill composed of a lower roller and a plurality of pairs of side rollers. The fin roller arranged in the cluster mill is split in two, one is a roller on the work side and the other is a roller on the drive side. The split fin rollers come into contact with a steel pipe to be formed at arbitrary positions in arbitrary directions in the circumferential direction of the steel pipe to be formed so as to conduct a fin pass formation. The plurality of fin pass forming rollers are arranged on a section different from the flow direction of the steel pipe to be formed.