一种物理模拟冲洗液冲洗效率的评价方法

Evaluation Method on Flushing Efficiency of Physical Simulation Flushing Fluid

实验室自行研制开发出了"高温高压泥饼冲洗效率评价仪",介绍了其结构、原理及使用方法,开展了一系列冲洗效率模拟实验。按10∶1的缩小比例制作了相应的缩小井筒模型,模拟砂岩地层,用PEM钻井液在高温高压环境下形成泥饼,在不同循环温度下对比评价了CW263L和CW268L冲洗液的冲洗效率,实验过程中可以自行控制泵送及冲洗时间。实验结果表明,该装置能够很好地模拟井筒的实际情况,包括钻井液所在地层的温度、压力、孔隙度环境,冲洗液对泥饼的冲洗效率,直观地表明了冲洗液性能的差异化。

A 'High temperature and high pressure mud cake flushing efficiency evaluation instrument' is developed inlaboratory,and the structure mechanics and using method of that are introduced.A wellbore model is made with theproportion ratio of ten to one to simulate sandstone formation,using PEM drilling fluid system to form mud cake in HTHP,applying CW263L and CW268L flushing fluid systems to evaluate flushing efficiencies in different circulating temperature,and the pumping and flush time is self-controlled while running.The laboratory results show that the instrument can simulatethe real situation in wellbore,such as temperature,pressure and porosity,the differences of flushing efficiency can also befound apparently.