赫谢尔－巴尔克莱液体直井稳态波动压力计算模式

An Accurate Steady Surge Pressure Model For Herschel-Bulkley Fluid in a Vertical Well

赫谢尔－巴尔克莱（Ｈｅｒｓｃｈｅｌ—Ｂｕｌｋｌｅｙ）流变模式是一个三参数模式，因其精度较高，近几年国内多用其描述钻井液的流变性。不过，与该模式相应的有关钻井水力学方面计算模式并不完善，影响了该模式的推广使用。本文以该模式为基础，从理论上推导并建立了直井起下钻或下套管过程中稳定层流条件下钻井液粘性产生的波动压力计算模式──—赫谢尔－巴尔克莱液体稳态波压模式。给出了有关计算公式和图表。本文为更准确地计算起下钻或下套管等钻井作业过程中井内产生的波动压力提供了理论依据。

For avoiding domnhole problem,control of surge presssure resulting from running or pulling a pipe in a boreholefull of drilling fluid is an important factor in drilling design and practice, and the methods which are used for predicting surgepresssure should be more accurate. The traditional computational errors need to be corrected.In this paper,an accurate model predicting steady surge pressure resulting from running or pulling a pipe in a vertical wellbore has been developed on thebasis of Herschel-Bulkley rheological model. Simple working formulae and graphs for computation are also given,which canbe used for determined surge pressure,safety maximum tripping velocity and also the drilling fluid rheological properties inthe field.