高温高压高酸性气田环空带压井风险级别判别模式

Risk level discrimination model for wells with sustained casing pressure in high temperature high pressure and high sour gas field

王云 李文魁

WANG Yun LI Wenkui

中国地质大学能源学院，北京　100083 中国石油勘探开发研究院，北京　100083

School of Energy Resources, China University of Geosciences, Beijing 100083, China Research Institute of Exploration and Development, PetroChina, Beijing 100083, China

气井环空带压是高温高压高酸性气田的普遍问题，环空异常带压将严重威胁气井安全生产，亟待进行完整性评价，判别风险级别，提出应对措施。基于环空带压的原因分析，以失效发生的可能性、危害性及当前状态为参数，依据相关行业标准，结合现场经验，提出影响气井完整性的30项因素，并逐一进行分级、评分、权重调整，建立了气井风险等级判别模式，可把气井的风险等级由低到高分为3类，Ⅲ类井需立即采取紧急处理措施。研究表明：气井生产工况和工艺措施决定完整性失效发生的可能性和危害性，当前状态是判别气井完整性最重要的参数，环空压力和泄漏速率可作为“一票否决”的参数。

Sustained casing pressure (SCP) is a common issue at high temperature, high pressure, and high sour gas fields. It will lead to serious threats to the safety of gas well production. It is very important and imminent to determine the risk level of the well. Based on international standards and the reasons of well losing integrity, 30 parameters affecting gas well integrity are proposed. And the influence of each parameter is evaluated respectively. Based on the combination of field experience and theoretical research, the single well scoring criterion and the model of evaluating well risk level are established. According to the risk evaluation model, the wells can be divided into 3 categories, Ⅰ, Ⅱ, and Ⅲ. Emergency measures need taking immediately for Type Ⅲ wells. The production characteristics and treating technologies can determine the possibility and severity of integrity losing. The current state is the most important parameter to evaluate the well integrity. The annulus pressure and leaking rate can be viewed as one-vote negation parameters.