深水井筒环空压力计算模型适应性评价

Adaptability evaluation of calculation model of annular pressure of deepwater wellhole

张百灵 杨进 黄小龙 胡志强 何藜

ZHANG Bailing YANG Jin HUANG Xiaolong HU Zhiqiang HE Li

中国石油大学北京石油工程教育部重点实验室，北京　102249 中海油能源发展股份有限公司工程技术深圳分公司，广东深圳　518067

MOE Key Laboratory of Petroleum Engineering, China University of Petroleum, Beijing 102249, China Shenzhen Branch of CNOOC Energy Techonnology & Services Limited, Shenzhen 518067, China

深水井筒在生产阶段受地层高温产出液的影响，温度场重新分布引起环空密闭空间的压力急剧上升，威胁井筒安全。为向深水油气井的井身设计和套管强度校核提供一定的依据，结合现场实例对基于状态方程和胡克定律计算模型和基于状态方程和温度压力耦合作用的迭代计算模型进行对比，对模型机理和影响计算结果的因素进行了分析。深水井筒中的环空流体介质复杂，井底高温及异常压力使得深水井筒中的环空中流体热膨胀系数和压缩系数对套管体积的影响难以利用胡克定律简化计算。结果表明，基于状态方程和温度压力耦合作用的迭代计算模型更适用于深水井筒的环空压力分析。

The deepwater wellhole is affected by high-temperature produced liquid of stratum in the production stage, and the redistribution of temperature field causes the sharp increase of pressure of annular confined space, threatening the wellhole safety. In order to provide certain bases for the wellbore design and casing intensity check of deepwater oil and gas wells, according to two kinds of calculation models, namely, calculation model based on equation of state and Hooke’s law and iterative calculation model based on equation of state and temperature and pressure coupling, as well as living examples on site, these two kinds of models are compared, the model mechanism and factors affecting the calculation results are analyzed, the annular fluid media in the deepwater wellhole are complicated, and it is difficult to conduct the simplified calculation of effects of coefficient of thermal expansion and coefficient of compressibility of annular fluid in the deepwater wellhole on the casing volume by virtue of Hooke’s law due to downhole high temperature and abnormal pressure. Pursuant to the results, the iterative calculation model based on equation of state and temperature and pressure coupling is more suitable for the annular pressure analysis of deepwater wellhole.

10.13639/j.odpt.2015.01.014