Abstract: Having a size range as O.D.210~2,000 mm×W.T. 150 mm(max.)×L 3,000~12, 000mm,the Julong (Giant Dragon) Piercing Mill is regarded the biggest one in the country in terms of product size range. Briefly introduced in the article are all the major aspects of the said plant,namely,technological design parameters,main composition of the equipment,maufacturing process flow and the equipment structural characteristics,etc.