高压气井环空压力管理图版设计与应用

环空带压是国内外气田普遍存在的气井完整性管理技术难题,科学的环空压力管理能够有效缓解环空带压问题的恶化,保证油气井的长期完整性。但目前国际上应用广泛的几种环空压力管理技术均无法满足中国石油塔里木油田公司(以下简称塔里木油田)超深层高压气井的管理要求,急需一套适合于该公司超深层高压气井的环空压力管理技术。为此,基于国内外现有的气井环空压力管理技术,综合考虑超深层高压气井A环空对应所有井屏障部件在不同生产和关井工况下的安全性,创新了一套A环空最大允许压力曲线和A环空最小预留压力曲线的计算方法 ;同时,兼顾安全性和可操作,通过进一步优化B、C、D环空最大允许压力计算的考虑因素和安全系数取值,提出了一套B、C、D环空最大允许压力计算新方法 ;进而设计完成了一套高压气井环空压力管理标准化图版。该项技术已在该公司所有高压气井进行了推广应用,有效地支撑了塔里木油田超深层高压气井的安全高效开发。

Design and application of annular pressure management chart for high pressure gas wells

Annulus with pressure is a challenge in the well integrity management in gas fields around the world. Sound annular pressure management can effectively alleviate the deterioration of annulus with pressure to maintain long-term oil & gas well integrity. However, the annular pressure management techniques widely used at present are unable to tackle the challenges faced by the high-pressure gas wells drilled in very deep formations in the Tarim Oilfield, and an applicable annular pressure management technology is in dire need. Under such background, an innovative method for computing the maximum allowable pressure curve and the minimum maintainable pressure curve for an "A" annuls was derived in this paper. The approach is based on the existing annulus pressure management techniques in the world, and takes into consideration the safety of all the well barrier parts in various production and shut-in settings. For easy operation, the factors influencing the maximum allowable pressures in the "B", "C", and "D" annulus are optimized, together with the safety coefficient, and a new method for computing the maximum allowable pressure in the "B", "C", and "D" annulus were accordingly presented. Based on the new method, a set of standard annular pressure management charts for high-pressure gas wells were designed. This new annular pressure management technique has been successfully applied in all high-pressure gas wells in the Tarim Oilfield, providing robust support for a safe and efficient development of the ultra-deep gas reservoirs in the area.