加砂压裂闭合点的确定方法  

Determination of closing point for sand fracturing

作　　者：黄志文[1] 王益维[1] 孙良田[1] 王培义[1] 

机构地区：[1]中国石化石油勘探开发研究院,北京100083

出　　处：《油气地质与采收率》2009年第5期104-106,共3页Petroleum Geology and Recovery Efficiency

基　　金：国家"863"项目"深层低渗透油气藏压裂改造关键技术"(2006AA06Z226)

摘　　要：在加砂压裂裂缝闭合过程中,闭合压力的确定对于评价压裂施工、获取准确的裂缝参数具有重要意义。通过分析加砂压裂裂缝闭合的机理,用数学方程分别描述了闭合点前、后的压力递减规律,根据压力特征曲线在闭合点前、后变化特征的不同,给出了确定闭合点的新方法。与视函数分析法和F函数分析法比较后发现,3种方法计算所得的闭合压力差小于0.1MPa,误差在1%以内,但新建方法具有所需参数较少且判断方法更为快捷的优点。Determination of closure stress in closure process for sand fracturing is significant for fracturing effect evaluation and accurate fracture parameters acquisition. After the physical process of closure procedure of sand fracturing was analyzed,the pressure decline rule was described by a set of mathematical equations before and after closing point. Aceording to the characteristics of the pressure curves,a new method of determining the closing point was put forward. Closure differential pressure is less than 0.1MPa with less than 1% error by three methods. Compared with the apparent and F function analytic approaches,the new method can identify the closing point for sand fracturing accurately and quickly with less parameters.

关 键 词：加砂压裂 裂缝 闭合点 压力递减 压降方程 

分 类 号：TE357.11[石油与天然气工程—油气田开发工程]