砂卵石地层钻探方法优化

针对砂卵石层钻进效率低下的问题,从钻进、取芯、孔壁支护3个方面出发,结合巴布亚新几内亚莱城港勘察项目,将采用不同钻具、取样方式、护壁方法钻进的试验结果进行对比,分析影响钻进效率的原因,并进行相应的优化。结果表明,影响卵石层钻进效率的主要原因是砂卵石层特殊的结构造成的卡钻、漏水等次生问题,而综合采用植物胶护壁以及与之相适应的钻头及岩芯管能有效减少次生问题的发生,提高钻进效率。

Optimization of drilling method for sandy pebble stratum

Aiming at the problem of the low drilling efficiency in pebble stratum,we take three aspects of drilling tool,core-taking and borehole wall protection based on geotechnical investigation of Lae Port project in Papua New Guinea,compare the results of drilling tests using different drilling tool,core-taking methods and borehole wall protection,analyze the reasons affecting the drilling efficiency,and optimize the method.The results show that the main reason affecting the drilling efficiency of the sandy pebble stratum is the secondary problems such as stuck drilling and water leakage caused by the special structure of the pebble stratum.With the plant glue mud and corresponding drilling tool can effectively reduce the occurrence of secondary problems and improve drilling efficiency.