In this study, the impact of VG69 organophilic clay on the rheological properties of gasoil-based drilling muds (invert emulsions) was investigated. The flow curves of gasoil-based drilling muds as a function of the dose of VG69 organophilic clay were analyzed by the Casson model. The addition of VG69 organophilic clay with a quantity range between 0 and 5 g in gasoil-based drilling muds induces an increase in the yield stress and the viscosity at an infinite shear rate of drilling muds. It is also proven that the addition of VG69 organophilic clay leads to an increase in the viscoelastic and thixotropic properties of the drilling muds. The study of the stability of gasoil-based drilling muds by centrifugation showed that for a quantity of VG69 organophilic clay lower than 3 g, the stability of the drilling muds increases and for a quantity of VG69 organophilic clay higher than 3 g, their stability decreases. The results obtained showed that the addition of 3 g of VG69 organophilic clay to the gasoil-based drilling mud increased the yield stress by 230%, the viscosity at an infinite shear rate by 3.4% and it improved the mud stability by 70%.

中文翻译：

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亲有机粘土对瓦斯基钻井液流变性能的影响

在这项研究中，研究了VG69亲有机性粘土对基于瓦斯油的钻井液（反相乳液）的流变性质的影响。通过Casson模型分析了以瓦斯油为基础的钻探泥浆的流量曲线随VG69亲有机性粘土用量的变化。在基于瓦斯油的钻井泥浆中添加VG69亲有机粘土，其含量范围在0到5 g之间，在无限的钻井泥浆剪切速率下，会引起屈服应力和粘度的增加。还已经证明，加入VG69亲有机性粘土会导致钻井泥浆的粘弹性和触变性增加。通过离心对瓦斯油基钻井泥浆进行稳定性研究表明，对于VG69亲有机性粘土，其含量低于3 g时，VG69亲有机粘土的量大于3 g时，钻井泥浆的稳定性增加，其稳定性下降。所得结果表明，向瓦斯油基钻井液中添加3 g VG69亲有机性粘土可使屈服应力提高230％，无限剪切速率下的粘度提高3.4％，泥浆稳定性提高70％。