High temperature and high pressure rheological properties of high-density water-based drilling fluids for deep wells

• Published in: Petroleum science 2012-09, Vol.9 (3), p.354-362
• Main Authors: Wang, Fuhua, Tan, Xuechao, Wang, Ruihe, Sun, Mingbo, Wang, Li, Liu, Jianghua
• Format: Article
• Language: English
• Subjects: Clay (material); Density; Drilling fluids; Earth and Environmental Science; Earth Sciences; Economics and Management; Energy Policy; Fluid flow; Industrial and Production Engineering; Industrial Chemistry/Chemical Engineering; Mathematical models; Mineral Resources; Power law; Rheological properties; Viscosity; 水基钻井液; 流变学特性; 流变性能; 深井; 高压力; 高密度钻井液; 高温度; 高温高压条件
• ISSN: 1672-5107; 1995-8226
• DOI: 10.1007/s12182-012-0219-4

To maintain tight control over rheological properties of high-density water-based drilling fluids, it is essential to understand the factors influencing the theology of water-based drilling fluids. This paper examines temperature effects on the rheological properties of two types of high-density water-based drilling fluids （fresh water-based and brine-based） under high temperature and high pressure （HTHP） with a Fann 50SL rheometer. On the basis of the water-based drilling fluid systems formulated in laboratory, this paper mainly describes the influences of different types and concentration of clay, the content of a colloid stabilizer named GHJ-1 and fluid density on the rheological parameters such as viscosity and shear stress. In addition, the effects of aging temperature and aging time of the drilling fluid on these parameters were also examined. Clay content and proportions for different densities of brine-based fluids were recommended to effectively regulate the rheological properties. Four theological models, the Bingham, power law, Casson and H-B models, were employed to fit the rheological parameters. It turns out that the H-B model was the best one to describe the rheological properties of the high-density drilling fluid under HTHP conditions and power law model produced the worst fit. In addition, a new mathematical model that describes the apparent viscosity as a function of temperature and pressure was established and has been applied on site.