气体钻井中钻屑对排砂管线易损段的冲蚀磨损研究

Study on Erosion of Vulnerable Section of Blooey Line in Gas Drilling

对排砂管线现场布局和工作特性的调研发现,旋转控制头和接地管线之间管段受冲蚀最为严重,失效破坏比例和风险最高。以该易损段为研究对象,应用CFD方法及Fluent软件,建立较为准确的冲蚀模型,研究冲蚀发生机制及位置,探讨管线冲蚀特点。结果表明:排砂管线入口第一个接头受冲蚀最为严重,同一工况下落地处接头冲蚀略微降低;随着注气量增加,各处冲蚀磨损程度也加大; T形接头抗冲蚀能力优于弯接头,但岩屑颗粒在T形接头封闭端易堆积,若不及时清理会失去一定的抗冲蚀能力。为尽可能降低冲蚀对排砂管线的影响,在满足正常生产要求的前提下,可采用适当降低注气量的措施。

Investigation on layout and working characteristics of blooey line shows that the pipe between the control head and the grounding line is seriously eroded,in which the failure risk is the highest.With this section as the research object,a accurate erosion model was established by using the CFD method and Fluent.The occurrence mechanism and position of erosion were studied,and the erosion characteristics of pipeline were discussed.The results show that the erosion of the first joint at the entrance is the most severely,while the erosion of the joint to the ground is reduced slightly at the same condition.As the gas injections increases,the degree of erosion is also increased.The erosion resistance of the T-joint is better than that of the bending joint.However,the debris particles are easily to accumulate at the closed end of T-joint,if not cleaned up in time,T-joints will lose some of the erosion resistance.In order to minimize the impact of erosion on blooey line,appropriate measures to reduce gas injection can be adopted on the premise of meeting the normal production requirements.