Research on Friction Drag Reducing Technology of Long Horizontal Shift Well—YYP3

Abstract:

Friction drag reduction is one of the key technologies in long horizontal shift well drilling. By optimizing the parameters of well track, a well track with low frictional coefficient is obtained. By the establishment of friction/torque analysis model, the influence of viscous force of drilling fluid and buckling of drill string on frictional drag was analyzed and friction/torque calculating formula was derived and a method to predict drag/torque was also presented. By using low friction coefficient oil-based drilling fluid, the friction coefficient was decreased by 65.2%. With casing floating technology, friction in casing running was significantly reduced. The above technologies were applied in well—YYP3, the friction in drilling process was accurately predicted to solve backing pressure in long horizontal shift well drilling and realize casing running in place in one time. The application in well-YYP3 show that these above technologies can be widely used in long horizontal shift well and can provide reference in long horizontal shift well drilling in other parts of China.

Key words:horizontal well; long horizontal shift distance; friction drag reducing; well track; oil-based drilling fluid; casing floating