针对长庆油田低压易漏层地层漏失问题,研发了适用于恶性裂缝型漏失的防侵微膨可固化堵漏工作液.实验结果表明,该体系固化前能有效防止井筒内其它流体污染,保证固化固化效果,并且在固化过程中具有一定的微膨胀效果,能有效防止漏层复发.通过3口井现场应用,堵漏成功且无漏层复发,该项技术为提高裂缝型恶性漏失区块的钻井成功率提供了重要技术保障.

气体钻井目前在国内外得到广泛的应用和发展,它具有提高机械钻速、降低钻井成本、最大限度地保护储层等巨大优势。我国空气钻井装备研发工作起步较晚,设备多为进口或带有较强的仿制色彩,存在某些不合理、不安全的地方,尤其供气管线的阀门设计不够合理,自动化操作程度不高。因此,对供气管线进行优化,对提高空气钻井的安全性显得尤为重要。

The application of nitrogen drilling at the highly abrasive gas-bearing Xujiahe Formation of the LG area is critical for the ROP improvement,reservoir protection,prevention of downhole explosion,and for further exploration and development in this area.Hereby,according to the practices and experiences from the nitrogen drilling in this formation on many wells,we summarized the equipments used,the technical challenges encountered,and the measures adopted as follows:1) the drilling rate should be controlled to be over 5 min/m in order to avoid sticking;2) if serious sticking occurs,work the drill string at a controlled pull force,and keep circulating continuously till no obstruction in the annulus,then readjust the work distance of the drill string in order to free it.The successful application of nitrogen drilling at the Xujiahe formation has proved that nitrogen drilling can not only improve the ROP effectively,but avoid downhole fires or explosions when drilling through gas zones with air.