The Research And Application Of Sylvite Copolymer Drilling Fluid Technology

In recent years, through the untiring effort of the drilling people, two big drilling lines work,"cost decreases and benefit increasing" and "drilling speed improvement", has made great progress and great achievements. But with the deepening of the work carried out, the pressure of "cost decreases" and "speed improvement" also increased year by year. Blocking effects of drilling complex are becoming more obvious on drilling speed improvement and cost decreases and benefit increasing. Now, in Daqing oil field, drilling fluid systems of deep skill, exploration well in middle and shallow layer, peripheral Fangzheng and Hailaer have had many improvements, but due to the limitation of inhibitory and anti-sloughing ability of systems, requirements of current drilling construction can not be met. On wellbore stability, phenomena of reducing, sidewall falling off, tripping stuck are frequent. Some technical measures such as strengthening tripping, optimization of well bore structure only are used to guarantee the smooth progress of construction. It not only increases the drilling cost and reduces the drilling efficiency, but also hinders the drilling speed improvement. According to the geological characteristics of Songliao basin, combining with "multiple collaborative" drilling collapse prevention principle:"seal/solid-inhibition-reasonable density", this study aims to develop drilling fluids system which has strong anti-sloughing and inhibition ability, and meet current requirements of "cost decreases and benefit increasing" and "drilling speed improvement" on inhibition and anti-sloughing.In this paper, construction characteristics which are suitable for deep skill, exploration well in middle and shallow layer, peripheral Fangzheng and Hailaer were researched, and combined with the actual field, sylvite copolymer drilling fluid system was developed and applied on site in Changyuan and peripheral field, Fangzheng, Hailaer district of Daqing oilfield. And good effect was obtained, economic benefit was obvious.