小口径岩心钻探钻孔缩径的预防与处理

Prevention of Borehole Diameter Shrinkage in Small Diameter Core Drilling and Treatment

摘要:

钻孔缩径是小口径岩心钻探经常遇见的问题，不仅严重影响施工进度，浪费施工材料，加大施工成本，严重时会造成孔内事故，甚至报废钻孔。通过几个实例，分析了缩径原因及其危害，介绍了事故的处理过程，总结了钻穿缩径地层的经验。

Abstract:

Borehole diameter shrinkage is frequently encountered in small diameter core drilling, which brings serious influence of construction progress, material waste, more construction cost and even downhole accident or abandoned. With several engineering cases, the paper analyzed the causes of borehole diameter shrinkage, introduced process of accident treatment and summed up the experience of penetrating diameter shrinking formation.