斜軋穿孔孔腔的形成及預(yù)防

Formation of Cavity During Rotary Piercing and its Prevention

摘要: 分析了穿孔毛管管坯中心出現(xiàn)孔腔的機(jī)理，根據(jù)滑移線場原理深入闡述了影響孔腔形成的力學(xué)因素，提出增加橫向附加壓應(yīng)力改善中心區(qū)域應(yīng)力狀態(tài)的思想，并據(jù)此提出減小導(dǎo)板間距的方法，以避免孔腔形成。實(shí)際應(yīng)用結(jié)果顯示：將穿孔機(jī)導(dǎo)板間距由151 mm調(diào)整至149 mm，可避免因頂頭前伸量過小引起的孔腔，有效改善管體壁厚均勻度。

Abstract: Analyzed in the paper is the forming mechanism of the cavity occurs in the center of a piercing shell. Based on the principle of slip line field，the mechanical factors leading to the formation of a cavity is elaborated.To avoid the formation of a cavity，the idea of improving the stress condition at the center area by adding a transversal compression stress is put forward，and so is the method of reducing the distance between the guide shoes.The application results indicate that when the distance between the guide shoes is adjusted from 151 mm to 149 mm，it is able to prevent the insufficient plug lead from causing a cavity，and to improve the homogeneity of pipe body wall thickness.