深水油气资源勘探开发中,由于水深的影响,海底及浅部地层温度低,而储层流体的温度相对较高,在钻井以及生产阶段,井筒内的钻井液或油流的温度明显高于浅部地层的温度,这样就导致套管柱各层套管之间环空的流体温度升高,如果各层套管之间的环空是一个密闭空间,必将导致压力的升高,压力升高到一定程度就存在挤毁套管的风险。因此,密闭环空的圈闭压力是深水开发钻井套管柱设计中需要考虑的必要因素。分析了环空圈闭压力升高的影响因素及计算方法,敏感性分析表明,油藏的初始静态温度、流体类型和生产流速、流体的特性、水泥浆封固位置对环空圈闭压力的影响较为明显。结合西非某油田实例,介绍了常用的释放环空圈闭压力的方法和现场应用效果,确定提高套管强度、套管设计中使用破裂盘、使用尾管代替套管和可压缩性泡沫材料,能有效释放密闭环空压力。 In deepwater oil and gas exploration and development, because of the influence of water depth, the temperature of the seafloor and shallow formation is low and the temperature of reservoir fluid is relatively high. During drilling and production, the temperature of drilling fluid or oil flow in wellbore is obviously higher than shallow The temperature of the formation, thus leading to the temperature of the fluid in the annulus between the casing layers of the casing string. If the annulus between casing layers is a confined space, it will inevitably lead to the increase of the pressure, To a certain extent, there is the risk of collapsing the casing. Therefore, the trapped annulus trap pressure is a necessary factor to be considered in the design of deepwater casing string. The influencing factors and calculation methods of annular trapped pressure increase are analyzed. The sensitivity analysis shows that the initial static temperature of reservoir, fluid type and production flow rate, fluid characteristics, The impact is more obvious. In combination with an example of an oil field in West Africa, the commonly used methods of releasing annular trap pressure and field application effects are introduced. The improvement of casing strength, the use of rupture disks in casing design, the replacement of casing and compressible foam by tail pipes, Can effectively release closed annulus pressure.