부산대학교 도서관

In order to solve the problem of bottom hole surge pressure generated during the drilling of high angle wells, the flow model of Casson fluid axial laminar flow in the eccentric annulus of high angle wells was introduced based on the influence of drill string eccentricity on the flow law of drilling fluid, the basic equation of one‐dimensional stable flow and the constitutive equation of Casson model, and the prediction model of surge pressure during the drilling of high angle wells was established in combination with the annular flow equation under the actual working condition of drill pipe; A new prediction method of surge pressure in high angle wells based on the Casson reheology model was proposed by solving the model using computer programming software. The calculation results show that this method is simple, fast and accurate, and has important guiding significance for the safe control of surge pressure during the drilling of high angle wells.