穿孔毛管尾部鐵耳子產(chǎn)生原因分析及控制

Investigation of Causes for Occurrence of Tail-end Fins of Pierced Shell and Relevant Preventative Actions

摘要: 從金屬塑性變形、管坯溫度、軋輥轉(zhuǎn)速等方面，分析了穿孔毛管尾部鐵耳子產(chǎn)生的具體原因，提出相應(yīng)的控制措施，并對控制措施的優(yōu)劣進行對比。分析認為：通過管坯尾部定心、抑制管坯尾部內(nèi)層金屬溫度升高過快及降低內(nèi)層金屬的剪切應(yīng)力，可以有效控制鐵耳子的產(chǎn)生；但對穿孔軋輥轉(zhuǎn)速進行線性控制，是控制鐵耳子產(chǎn)生的最優(yōu)方案。

Abstract: Investigated are the specific causes for occurrence of tail-end fins of the pierced shell， involving such aspects as metal plastic deformation，billet temperature and roll rotation speed，etc.Accordingly，preventative actions are proposed，and advantages and disadvantages of the actions are compared with each other.As a result，it is concluded that the occurrence of the said fins can be properly prevented by means of billet tail-end centering，restraining temperature over rise of the billet’s tail-end internal metal，and decreasing the shear stress thereof.Nevertheless linear control of the piercing roll rotation speed is the best way to prevent occurrence of the fins during the piercing operation.