复杂地层用绳索取心钻具的研制

常规绳索取心钻具在复杂地层钻进时，岩矿心采取率会降低的原因主要有2个：一是钻具防水性能差，遇到松散软的地层时，岩心没有进入岩心管时就被冲洗液冲蚀掉了；二是钻具防岩心脱落性能不好，遇到硬脆碎地层时，虽然岩心能够进入岩心管，但卡簧对破碎的岩心卡固不牢，很容易脱落。复杂地层用绳索取心钻具是以解决这两大问题而设计的，并使绳索取心钻进的优越性得到充分的发挥。

Development of wire-line drilling tools for complex formation

Using the conventional wire-line drilling tool in complex formation always leads to low core recovery. There are two main causes: firstly, because of poor waterproofness of the conventional wire-line drilling tool, the core is eroded by flushing fluid before entering the core barrel during drilling in loose soft formation; secondly, it has poor performance in preventing core loss in hard, brittle, broken formation since the core lifter cannot lock tightly the core, even though the core can enter into core barrel, leading to core falling off. A wire-line drilling tool is designed to solve these two problems for complex formation, and also exploit the advantages of wire-line drilling at best.