DEVELOPMENT OF STEEL TUBE ROLLING IN JAPAN

Abstract

In Japan, many tube manufacturing equipments have been improved and excellently. progressed during last decade. Fourteen electric-resistance-weld tube mills have been installed and one continuous buttweld tube mill is under operation. But the operation of two Ehrhardt push-bench-type seamless-tube mills have been suspended. In tube-finishing plants, many new threading machines have been imported, and a new cold-drawing machine and a Rockrite rolling mill have been installed. Now many experiments are being made on the cold tube-drawing process with the back tension.