A STUDY CONCERNING TRIAL PRODUCTION OF SMALL-SIZED PIPES AS BLANKS FOR COLD-DRAWN PIPES VIA Φ76mm PLUG MILL LINE

Introduced in the paper are relevant processes, process data and technical measures taken for the trial operation of the Φ76mm plug mill line to produce small-sized hot-rolled mother tubes.A comparison of the said mother tube with that from previous process is made to show the former's advantages in terms of cold-drawing passes, yield and yield loss when used as blank for thin-walled cold-drawn pipe.Relevant operation has proven that the employment of the Φ76mm plug pipe mill line to produce small-sized hot-rolled mother tubes for cold-drawn pipes can not only enlarge the product-mix of the mill line, but also bring about more reasonable process technology for smallsized, thin-walled cold-drawn steel pipes.