Abstract: By using a Chan-7400 HTHP rheometer,we have studied experimentally the rheological properties of a low-density oil-in-water emulsion mud.Effects of temperature & pressure on the properties of this drilling fluid have been measured systematically.Four rheological models,namely Bingham,Power-Law,Casson,and Hershel-Bulkley have been applied to analyze the tested data.The results show that Herschel-Bulkley model is the best one to describe the rheological behavior for this fluid.As for engineering application,the two parameters of Casson model can also be used to characterize the rheological properties of a oil-in-water emulsion at HPHT.The rules of different parameters in Hershel-Bulkley equation,which change with the temperature and pressure have been investigated.Morever,this paper has analyzed the HPHT rehological data.Model to predict the rheological properties at HPHT has been presented.

Key words: oil-in-water emulsion, drilling fluid, high temperature, high pressure, rheological property, rheological model, rheometer

摘要： 用7400型高温高压流变仪对“八五”期间研制的华北任平1井低密度水包油乳化钻井液高温高压流变性进行了实验研究。系统地测试了温度、压力对该钻井液流变性的影响;运用宾汉模式、幂律模式、卡森模式和赫-巴模式对该钻井液高温高压流变数据进行了系统拟合分析,得出赫-巴模式是描述该钻井液高温高压流变性的最佳模式,就工程应用而言,二参数的卡森模式也可以用于描述水包油乳化钻井液高温高压流变性。并研究了赫-巴流变方程中各参数随温度和压力的变化规律;还对该钻井液高温高压流变数据进行了回归分析,建立了预测低密度水包油乳化钻井液高温高压流变性能的模式。

关键词: 水包油乳化液, 钻井液, 高温, 高压, 流变性, 流变模式, 流变仪