固相含量和密度对高密度钻井液流变性影响的实验研究

Experimental study on the effect of solid content and density of high density drilling fluid on its rheological properties

高密度钻井液体系的研究和应用中,流变性是重要的衡量标准,而固相含量和密度又是影响高密度钻井液流变性最重要的因素。通过机理分析,并根据大量室内试验研究了在高温条件下,高密度钻井液固相含量和密度的变化对其流变性能的影响规律和程度。通过对钻井液表观黏度、塑性黏度、动切力和静切力等流变参数的变化进行测定和计算,对不同固相含量(2%～6%)的高密度钻井液流变参数曲线变化进行对比得出:含土量增大,钻井液的黏度增大;高密度钻井液的流变性受固相含量大小和温度的影响明显、受压力和添加剂的影响较小。该试验研究结果将对钻井现场高密度钻井液的应用具有重要的借鉴作用。

The rheological property is an important yardstick in the study and application of high density drilling fluid. The solid content and the density are the most important factors that affect the rheological properties. In this paper, with the help of mechanism analysis and lots of experimental results obtained in laboratory, the law and the extent of the effect of the variation of solid content and density of high density mud on the rheology are studied. The variation of such rheological parameters as AV, PV, Yp and Gel are measured and calculated. The curves of rheological parameters of high density drilling fluid with the solid content ranging from 2% to 6% are contrasted. It is concluded that the higher the clay content is, the higher the viscosity gets. The rheological property of the high density drilling fluid is influenced greatly by solid content and temperature, while it is less influenced by pressure and additives. The result will be significant to the application of high density drilling fluid to the drilling site.