长输管道干线改造施工需要在短时间内完成 ,其中关键的工序是管线对口。本文对长输管道干线施工对口存在的质量缺陷进行了阐述 ,对缺陷形成的原因进行了比较详尽的分析 ,在此基础上提出了改进的办法 The construction of long-distance pipeline trunk lines needs to be completed within a short period of time, of which the key process is the pipeline counterpart. This paper elaborates on the quality defects existing in the counterpart of long-distance pipeline construction and makes a detailed analysis of the reasons for the formation of defects. On the basis of this, an improved method is proposed