如何获得尺寸更小和质量更好的无缝异型钢管，必须采用冷轧、冷拔或者两者联合的方法。冷轧通常在二辊式轧机上进行，精密无缝异型钢管在变断面圆孔槽和不动的锥形顶头所组成的环形孔型中轧制。无缝异型钢管通常在0.5～100T的单链式或双链式冷拔机上进行。
In order to obtain seamless special-shaped steel tubes with smaller size and better quality, cold rolling, cold drawing or combination of the two methods must be adopted. Cold rolling is usually carried out on a two-roll mill. Precision seamless special-shaped steel pipe is rolled in an annular pass consisting of a circular groove with variable cross-section and a fixed conical head. Seamless profiled steel pipes are usually carried out on single-chain or double-chain cold-drawing machines of 0.5-100T.
热轧管一般在自动轧管机组上生产。实心管坯经检查并清除表面缺陷，截成所需长度，在管坯穿孔端端面上定心，然后送往热风炉加热，在穿孔机上穿孔。在穿孔同时不断旋转和前进，在轧辊和顶头的作用下，管坯内部逐渐形成空腔，称焊管。再送至自动轧管机上继续轧制。最后经均整机均整壁厚，经定径机定径，达到规格要求。利用连续式轧管机组生产热轧无缝异型钢管是较先进的方法。
Hot-rolled pipes are usually produced on automatic pipe rolling mills. The solid billet is checked and cleared of surface defects, cut into the required length, centered on the end face of the billet perforation, then sent to the hot blast stove for heating, and perforated on the perforator. With the continuous rotation and progress of perforation, under the action of rolls and pins, a cavity is gradually formed in the billet, which is called welded pipe. It is then sent to the automatic pipe mill to continue rolling. Finally, the wall thickness of the whole machine is equalized, and the sizing machine is used to calibrate the diameter, which meets the requirements of specifications. It is an advanced method to produce hot-rolled seamless special-shaped steel pipe by continuous pipe rolling mill.
精密无缝异型钢管和热轧管规格：热轧管外径32～630mm。壁厚2.5～75mm。精密无缝异型钢管外径5～200mm，壁厚2.5～12mm。
Specification of precision seamless special-shaped steel pipe and hot-rolled pipe: the outer diameter of hot-rolled pipe is 32-630 mm. The wall thickness ranges from 2.5 mm to 75 mm. Precision seamless special-shaped steel pipe has an outer diameter of 5-200 mm and a wall thickness of 2.5-12 mm.
