笔者在查阅国内外有关资料和深入现场进行大量调研的基础上,对钻铤螺纹各种早期破坏形式进行归类,并对发生早期破坏的原因进行了分析。文末笔者对这一课题的深入研究提出了几点建议。 On the basis of consulting domestic and foreign relevant information and conducting extensive investigations in depth, the author classifies all kinds of early destructive forms of thread collars and analyzes the causes of the early damage. At the end of this article, I put forward some suggestions on this topic in-depth study.