煤层气多分支水平井钻井技术实践

COAL BED MULTI-LATERAL WELL DRILLING TECHNOLOGY AND ITS APPLICATION

我国的煤层气资源丰富,储量巨大。煤层气的开采已有十余年历史,煤层气钻探技术有了长足的发展。斯伦贝谢中国公司最先涉足中国煤层气多分支井的钻探并获得显著的钻探成果。介绍了斯伦贝谢中国公司的多分支水平井工艺技术流程;简要列举了煤层气钻探的主要技术装备和地质导向必需的随钻测井仪器;阐述了煤层气多分支水平井的主要工程难点和主要关键技术;重点分析了部分前期已钻多分支水平井的钻井效果,描述了多分支水平井的钻井速度、钻井周期、悬空侧钻耗时、煤层钻遇率等关键技术指标随钻井熟练程度不断提高的变化趋势。通过前期16口多分支水平井的钻后资料分析,文章总结了施工中获得的经验教训。钻探实践表明,运用多分支水平井地质导向技术钻探煤层气,可以大幅度提高煤层气产量,获得良好的经济效益和社会效益,前景广阔。

In China,CBM has a tremendous number of reserves. The exploitation of CBM has been carried out for more than ten years,so there was a considerable progress in CBM multi-lateral drilling technology. Schlumberger China Company has firstly engaged in the drilling of CBM multi-lateral well and obtained prominent achievements. This article mainly introduced the technical drilling procedures of CBM multi-lateral wells in Schlumberger China Company and briefly listed the main technical equipment of CBM drilling and MWD meters while using well placement technology. It introduced the challenges in projects and the key technical points of CBM multi-lateral drilling. There was also an emphasis on analyzing the drilling results of drilled multi-lateral wells and the variation trend of the critical performance factors in CBM multi-lateral drilling such as rate of penetration,construction well period,open hole sidetrack hours and net to gross ratio. This article summarized some lesson learns and experience which have been gained from the CBM drilling operation after performing post drilling analysis on 16 drilled multi-lateral wells. The drilling practice indicated that the daily CBM production would be increased sharply,at the same time,the economic benefit and the social benefit would be acquired substantially after using well placement technology in CBM multilateral wells,and CBM would have a bright future in China.