Abstract: Tianjin Steel Tube Corp. has taken successfully the polit production of lower & medium pressure boiler pipes by means of the process that the Φ270mm continuous cast round is first rolled on the Φ650mm pipe mill into the Φ110mm mother tube which is then further processed into the lower or medium pressure boiler pipe with the Φ100mm plug mill.The pipes of the trial production are in full compliance with all the relevant technical criteria as specified under the applicable Chinese Standard GB3087-82.