Research On Water-based Drilling Fluid Of Deep Well In Daqing Oilfield

Now Daqing oilfield use oil-based drilling fluid which is expensive and contaminative, so I do research on water-based drilling fluid for Daqing oilfield. With the higher the well is, the higher formation temperature is, I analyses the influence which high temperature impact on clays, drilling additives and drilling systems. On this basis, I optimize the better drilling additives with excellent competitive, stabilizing agent GWJ, anti-collapse agent YGT, high temperature fluid loss agent KFT, high temperature thinner OCL-GNT, solid lubricant OCL-RH, high thermal stabilizer YGB-1, in the end, make the reasonable additives with theirs dosages, and Determine water-based drilling fluid system formula through experiments. Considering the deep drilling process may appear abnormal high pressure, this paper studies the weighing performance of water-based drilling fluid, experiment results show that this water-based drilling fluid system density can increase to 2.0 g/cm~3, rheology behavior of drilling fluid also meet requirement. In addition, evaluate thermal stability, anti-pollution, inhibition of water-based drilling. Evaluation results show that this water-based drilling fluid system has good rheology and can protect reservoir. It is easy to control and meet drilling requirements.