Drilling hydraulics calculation for extended-reach wells.

摘要

Extended-reach wells (ERW) are currently designed by first proposing different well plans based on certain input parameters, such as regional lithology, pore pressure and fracture gradients, surface location, and target depth of reservoir. Using this information, technical and economic feasibility of the proposed well is assessed, which addresses various drilling aspects such as hydraulics, wellbore cleaning, wellbore stability, and torque and drag.; The objectives of this project are (i) to develop an algorithm for calculating the drilling hydraulics in ERW, and (ii) to perform a parametric study to investigate the effects of casing size and setting depth on ERW design. An algorithm was developed to calculate the x and y coordinates of a build-and-hold type well profile. Drilling hydraulics calculations were performed based on the constraints of efficient wellbore cleaning and maximum rate of penetration (ROP). The maximum drill bit hydraulic horsepower such as 66% of mud pump hydraulic horsepower and 34% to overcome frictional losses, was selected as a design parameter for optimum hydraulic assessment. (Abstract shortened by UMI.)