煤层气径向钻井压耗计算与井口压力预测

发布时间：2018-01-20 15:41

本文关键词： 煤层气径向井水力冲蚀破碎压力压耗压力预测　出处：《煤田地质与勘探》2017年04期 　论文类型：期刊论文

【摘要】：对煤层气径向钻井过程中钻井管柱系统压耗和高压水射流破岩机理进行分析,列出了钻井管柱系统各部分磨阻系数的计算公式和喷嘴射流动力公式。通过理论分析与室内试验,提出了煤的水力冲击破碎压力与其物理力学参数之间的关系式,以及水力冲蚀速度与无因次冲击压力之间的关系。结果表明:通过加权平均值法计算得到的临界破碎压力与实际值吻合良好;在3~8倍临界破碎压力下,冲蚀速度约为无因次冲击压力的0.4倍。根据文中压力预测步骤,对现场作业进行压力预测,得到的井口压力预测结果比实际施工压力低3~5 MPa。
[Abstract]:The pressure consumption of drilling string system and the rock breaking mechanism of high pressure water jet during radial drilling of coalbed methane are analyzed. The formulas for calculating friction coefficient of various parts of drilling string system and the dynamic formula of nozzle jet are listed. Theoretical analysis and laboratory test are carried out. The relationship between the hydraulic impact crushing pressure of coal and its physical and mechanical parameters is presented. And the relationship between hydraulic erosion velocity and dimensionless impact pressure. The results show that the critical breaking pressure calculated by weighted average method is in good agreement with the actual value. Under the critical crushing pressure of 3 ~ 8 times, the erosion rate is about 0.4 times of the dimensionless impact pressure. According to the pressure prediction steps in this paper, the pressure prediction is carried out on site. The predicted wellhead pressure is 3 ~ 5 MPa lower than the actual construction pressure.
【作者单位】：中国石油大学(北京)煤层气研究中心;
【基金】：山西省煤基重点科技攻关项目(MQ2014-04)~~
【分类号】：TD842
【正文快照】： 引用格式:张彪,张遂安,董银涛,等.煤层气径向钻井压耗计算与井口压力预测[J].煤田地质与勘探,2017,45(4):170 174.ZHANG Biao,ZHANG Suian,DONG Yintao,et al.Friction loss calculation and wellhead pressure prediction in CBM radial drilling[J].Coal Ge-ologyExplorat

【相似文献】