The Ba Shentuo Complex Formation In Drilling Fluid Technology

The formation of Bashituo field is complex, who has the different formation pressure system including the high pressure, the low pressure salt water level and the oil gas level, often appears complex conditions such as brine leaching, sticking on multiple salt bed, leaking, collapsing, blocking and so on during the process of welldrilling.The higher the temperature and pressure of the wellbore get, and so the mud will lose original performance easily under the high temperature.In the recent years, the exploration and development of deep oil and gas in Bashituo field is reinforced. The current drilling fluid can hardly meet the need of deep well drilling, so the water based drilling fluid system which is applicable to deep exploration well in Bashituo is studiedThis paper analyzes geology engineering character of local region through looking up to a great deal of domestic and abroad relevant technology and related data of Bashituo field. For those wells who have been drilling finished, we understand their technology of the drilling fluid and problems, put forward a choice of fluid system solutions.In this article, it optimizes the high density (2.20g/cm~3) water-base (brine Cl~-< 100000mg/l, brine Cl~->100000mg/l) drilling fluid system. This system has the properties of strong rejection capability, good theological properties, good sealing capability, abrasion resistance, whose anti-high temperature is 150度, controllable density is 2.20.which is better than the current system used in the Tarim. And it is prone to maintain the performance.