Abstract: The Φ108 mm Assel mill located at Hunan Hengyang Steel Tube(Group) Co.,Ltd.is the first China-made 3-roll pipe-rolling mill.The company has modified the mill into a Φ219 mm one for the purposes of expanding the capacity,increasing the class width,improving product quality,and enhancing cost effectiveness.Elaborated in the paper are the main aspects of the said Φ219 mm Assel mill resulting from the modification,including the manufacturing process flow,characteristics of the equipment and technological performance parameters of the hot-rolling section,technical modification features and the shortcomings as still existing at present.