Research On High-Density Drilling Fluid Technology With High Temperature Resistance For Deep Drilling In Tarim Oilfield

With the current development of the deep drilling technology, demands for high-density drilling fluid with high temperature resistance grows rapidly, and various technical problems has become increasingly prominent as more deeper wells turned up. Among all the influence factors, the quality of drilling fluids is the key of drilling cost, drilling rate during the drilling of high temperature deep wells, geothermal wells and gas wells, high temperature geothermal wells.Down deep and more pressure, following the requirement that the drilling fluids must have a high density, and in consequence, high density also leads to high solid content as a result. And the filtration property and rheological control of drilling fluids at high temperatures are the difficulties of high temperature resistant drilling fluids technology. Therefore, the drilling fluids temperature resistance performance has become the most important and also the basic requirements. For these descriptions above, the study is focused on high temperature resistant drilling fluids system from the rheological and filtration control of drilling fluids in this work with the latest international technology development. Based on domestic and foreign literature, it analyses the situation of high temperature resistance drilling fluids formulation and high temperature resistance treatment agent. It researched on the influences to the drilling fluids by clay, heavier materials etc.in high temperature condition, and analysis its technical characteristics and difficulties of high temperature resistance. The principle how the treating chemical affects the property of drilling fluids was analyzed.One set formulation of high density drilling fluid with high temperature resistance (up to 160?) was developed finally. By the research of sedimentation stability and filtration property of the high-density drilling fluids composition in high temperature conditions, the laboratory experiments show that, this drilling fluids formulation has a good rheological behavior and filtration property to meet the requirements of.high temperature and high pressure stratigraphic condition. The successful field experiment in Well Keshen-8 demonstrates a good prospects of the developed high density (2.28?2.32 g/cm3) drilling fluid with high temperature(up to 160?) resistance.