油套管螺纹的“黑皮扣”现象浅析

Analyses of “black-crest thread”phenomena on tubing and casing thread

"黑皮扣"是油套管螺纹加工中的难题,也是油套管螺纹接头测量和使用的隐患。介绍了标准API与特殊螺纹油套管"黑皮扣"的定义与判定方法、油井管生产与检验过程中对"黑皮扣"认识的误区、"黑皮扣"在使用过程中的危害。重点从管体来料、加工工艺方面,解析了油套管螺纹加工产生"黑皮扣"的原因及改进措施。通过调整螺纹锥度和中径等,减少"黑皮扣"产生的概率,对油套管设计、加工生产与检验具有指导意义。

＂Black crest thread＂on the tubing and casing connection is always a manufacturing puzzle,and also a hidden trouble in its thread measure and application. Definition and decision of＂black crest thread＂,the misunderstanding of＂black crest＂in manufacturing and measure process,and the hazard in the field application are introduced. From incoming pipe and manufacturing process aspects,mainly analyze the cause and solution in the threading. According to definition pipe OD,end straightness and ovality,to adjusting of thread taper and pitch diameter,can reduce＂black crest thread＂pipe. Tubing and casing designing,threading process and inspection can be referenced in this paper.