大口径TA2钛管斜轧穿孔过程粘钛缺陷及其对毛管质量的影响

Sticking Defects and Its Influence on Shell Tube in Rotary Piercing Process of Large Diameter TA2 Titanium Tube

针对大口径TA2钛管斜轧穿孔过程中的粘钛问题,通过工业试验研究,分析其对穿孔后毛管的表面状况、变形缺陷、尺寸精度等的影响,以及微观组织分布。结果表明:导盘粘钛及处理延长了轧制工艺时间,涂层对粘钛具有一定的抑制作用,但单支穿孔轧制轧后基本失效。斜轧穿孔过程后毛管的退火组织为等轴晶,且晶粒获得很大程度的细化,导盘粘钛及处理时间对晶粒尺寸的影响不大。为此,采取了相应的措施减轻了粘钛程度,如:严控加热炉温度、优化布料方式、采用耐磨性更好的铸铁导盘等,有效提高了毛管表面质量和减轻了导盘损耗。

Aiming at the problem of the sticking defects in the rotary piercing process of large diameter TA2 titanium tube,the influence of the sticking defects on the surface condition,deformation defect,dimensional accuracy and other macro-quality of the pierced shell tube and the micro-structure distribution were analyzed.The results show that the rolling process time is extended due to the sticking defects and its treatments of the guide plate.The coating has a certain inhibition effect on the sticking defects,but it is basically failed after the single pass piercing rolling.The annealing micro-structure of the tube is equiaxed grains and the grain size is refined to a great extent after the rotary piercing process.The influence of the discs sticking defects and the process extension time on the grain size is not obvious.Therefore,the corresponding measures,e.g.control of the furnace temperature,optimization on feeding mode and adopting guide discs of cast iron,were taken to reduce the titanium sticking degree,which effectively improve the surface quality of the shell tube and reduce the loss of the discs.