气体钻井连续循环短节旁通阀的设计与分析

摘要

The continuous circulation sub for gas drilling can effectively address problems such as hole bottom pressure being hard to control, the operation pressure window between formation pore pressure and break pressure being small, severe wellbore ballooning effect and accident inlfux of oil or gas. A bypass valve for continuous circulation sub is designed in the side hole of the sub body. No mat-ter it is open or closed, the circulating media will produce impact force on it, which may damage its strength, and the circulation medium may leak out when it is closed. The ANSYS software was used to simulate the mechanical behavior of the valve under both closed and open conditions, and furthermore analyzed the dangerous section of the valve body. The result shows that this valve construction satisifes the strength demands under various working environments and the bypass valve needs to be securely sealed when closed. The research also completed the design and analysis of the sealing pair for the bypass valve.%气体钻井连续循环短节能有效解决井底压力不易控制、地层孔隙压力与破裂压力之间的操作压力窗口窄小、井眼鼓胀效应严重以及油气意外入侵等难题。设计了一种气体钻井连续循环短节，对其核心组件旁通阀在两种工况下受力状态进行了分析：关闭和打开两种工况下循环介质均会对阀体局部产生冲击力，易造成阀体局部强度破坏，且旁通阀关闭时，容易出现循环介质泄漏的情况。利用ANSYS有限元分析软件模拟了旁通阀处于关闭和打开两种工况下阀体的力学行为，对阀体危险截面进行分析。结果表明，该阀体结构满足各种工况下的强度条件，且旁通阀处于关闭状态时对密封性能有严格要求。研究同时完成了旁通阀密封副的密封设计分析。