提高煤层气水平井玻璃钢管固井顶替效率技术研究

Research on Enhancing Displacement Efficiency of FRP Pipes Cementing in Coalbed Methane Horizontal Well

煤层气玻璃钢管固井可以有效的防止后期采煤作业时电火花和摩擦火花的产生，降低采煤作业瓦斯爆炸的风险．然而由于玻璃钢管的密度较低，固井时玻璃钢管在水平井眼内的位置及居中情况与钢制套管有较大差异，需要根据玻璃钢管固井的特点制定相应的顶替效率提高措施．根据水平段玻璃钢管固井顶替时的受力变形、居中度以及顶替界面形态分析，提出了针对煤层气水平井玻璃钢管固井的“本体悬浮、居中度优化、整体平直下偏心”三项顶替效率提高技术，从而保证顶替界面的最小掺混长度以及顶替界面的整体近似匀速移动，为煤层气水平井玻璃钢管固井参数设计提供了理论依据与方法．

In coalbed methane horizontal well, caused by coal mining process, and reduce the risk FI^P pipes cementing can avoid the spark of gas explosion. Because of the low density of FRP pipes, compared with steel casing, FRP pipes is greatly different in terms of location and centrality inside the wellbore. For improving displacement efficiency, it＇s necessary for establishing cementing measures. On the basis of analysis on mechanical characteristics, cen- trality and replacement interface form of FRP pipes during cementing, this paper proposes three measures, including casing floating, centrality optimization and entire downward eccen- tricity. For ensuring mix minimum length and approximate uniform motion of replacement interface, this paper provides a theory basis for the optimization, design of displacing parameters with no doubt.