Abstract: Described here in details are the main aspe cts of the manufacturing technology and equipment of Φ508 mm PQF 3-roll mandrel pipe mill,including the specific processes,technical data and equipment characteristics,etc. of the major mill units such as the rotary heating furnace,the piercer,the PQF mandrel mill proper and the sizing mill. Also elaborated are the process control system and the quality assurance system of the mill. When the pipe mill is being designed,all the weak points of the mandrel mills similar to it are taken into consideration,and then eliminated by certain major modifications. All the modifications have brought about significant effectiveness to the mill plant in terms of cost-saving,profit increasing and product quality improvement.