高压注气管柱的设计和强度校核研究

DESIGN AND SAFETY CHECK OF GAS INJECTION STRING WITH HIGH PRESSURE

随着气体增压技术的发展,高压注气在油气田的应用越来越广泛,为了适应高压注气的工况,对注气管柱进行合理设计和安全性校核显得十分必要。为此,文章结合海洋某油田的一口拟高压注气井,提出了进行注气管柱的设计和强度安全性校核的方法,结合注气管的受力分析和实钻井眼轨迹及实际工况,并充分考虑轴向力、外挤和内压力对注气管强度的影响,进行三轴应力强度校核。在气体压力计算方面,应该考虑封隔器的安装和注气条件下气体所产生的压力。文章提出的注气管柱设计和校核方法已在现场得到了应用。

Under-balanced gas drilling and completion technology is a new one, which can prevent reservoir damage from external fluids and minimize the reservoir damage in the whole process from drilling to completion. In recent years, by solving the key technical problems, the under-balanced gas drilling and completion technology is perfected in Sichuan Petroleum Administration (SPA). The article introduces the implementing conditions of under-balanced gas drilling and completion. With numerical simulation software, pressure distribution, velocity distribution, annular cutting concentration distribution and influence of choke pressure are analyzed. The influence of formation fluid intruding on gas drilling is discussed. The relation between the gas flow rate and the bottom hole pressure is analyzed. It is explained how to determinate the injection parameters, the cycle flow procedures, the drilling and,completion measures of under-balanced gas drilling and completion. The technology is applied in Wells Jinqian 2, Pingluo 19 and Baiqian 111 H. and good technical and economical benefits are achieved.