深水钻井测试与生产过程井口抬升计算

Analysis of Wellhead Growth of Deepwater Well During Production and Well Testing

建立了深水井测试及生产过程中井口处产生的热膨胀力与井口抬升量力学模型,结合具体井身结构计算了井口热膨胀力与抬升量,并分析了各层套管水泥浆返高与温度变化对井口热膨胀力与抬升量的影响。结果表明:井口处产生的热膨胀力远大于剪切销钉的承载力,很容易造成剪切销钉剪断,从而导致井口抬升;表层套管水泥浆返高对井口抬升量的影响最大,生产套管影响最小,各层套管的水泥浆返高对井口总膨胀力均无影响;随着各层套管温度的升高,井口总热膨胀力及井口抬升量均线性增大。可为水下井口设计和测试及生产过程中的参数设计提供理论依据。

In order to calculate the thermal expansion force and wellhead growth of deepwater drilling during well testing and production,the mechanical model and analysis method of multilay-er casing suspension on wellhead have been established.The thermal expansion force and wellhead growth have been figured out through a specific well structure and the influence of top of cement (TOC)and temperature variation on wellhead growth have also been analyzed.Results show that,during well testing and production,the thermal expansion force on wellhead is far bigger than the bearing capacity of the sheared locking pin and the sheared locking pin is easily to be cut that would result in wellhead growth.The TOC of surface casing has greatest impact on wellhead growth and the production casing has the smallest impact.The TOC of all casing has no influence on the thermal expansion force.With the increase of temperature of all casing,the thermal expansion force and wellhead growth increase linearly.The research has some theoretical foundation for the design of subsea wellhead and parameter design of deepwater drilling during well testing and production.