针对目前井下钻井液密度的计算问题, 在综合已有的复合模型、经验模型计算法的基础上, 结合现场钻井液运用情况, 提出一种适用于高温高压下钻井液密度的简易计算方法。分别研究液相水、液相油密度随井下温度、压力的变化规律, 并考虑实际钻井液液相水、液相油的组分, 根据体积比系数计算井下钻井液的密度值。选取具有一定代表性的水基、油基钻井液进行实例验证, 结果表明该简易计算方法的计算精度能够满足工程要求, 且具有计算简便、可操作性强等优点。
For calculation of density of drilling fluid in down-hole HTHP environment, a simplified calculation method is presented, which combines the composite model and empirical model methods with the actual on-site drilling operation. The method solves the liquid density calculation in drilling fluid composition by considering the liquid water and the liquid oil density changing with temperature and pressure as well as taking into account the components of drilling fluids. Experiment verification with a certain typical water-based drilling fluid and oil-based drilling fluid shows that the method can not only meet the calculation precision demand of engineering but also provide an easy calculation means of high operability.
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