RESEARCH AND APPLICATION OF ORGANIC SALT DRILLING FLUID IN DAGANG OILFIELD HORIZONTAL WELLS

Strong inhibitive water base mud is mainly used for oil well drilling in Dagang oilfield currently. According to different drilling regional condition, different drilling fluid is used to meet the different needs of drilling. Formate mud, silicate anti-sloughing drilling fluid and organic positive gel drilling fluid are mainly applied to solve much horizontal well drilling technical problems, such as hole cleaning, hole stabilization and anti-sticking,ect., so they can meet the horizontal well drilling technical need. But cake formed by drilling fluids and filtrate into the reservoir block the oil and gas path, the characteristics of the large drainable area were limited. Hence, the double insurance type of organic compound salt drilling fluid (BH-WEI) system was developed by Bohai Drilling Technology Service Company. This fluid system has characteristics of steady performance, strong inhibitive, environmental protection and solidfree, it is beneficial to improve the penetration rate and the quality of cementing, resolve conflicts between hole stability and reservoir protection. With its applying in Dagang oilfield, very good results have been achieved.