Design and testing method of push-the-bit rotary steerable system bulid-up-rate evaluation device

For static push-the-bit rotary steerable drilling tool assemblies, existing build-up-rate(BUR) prediction methods are mostly theoretical calculations. Due to simplified modeling conditions, there are often errors in BUR prediction. To this end, based on the working principle of push-the-bit drilling tools, a set of static push-the-bit steerable drilling tool combination BUR evaluation device and evaluation method were established. The inclination ability of different drilling tool combinations was compared using the measured lateral force and deflection angle at the drill bit, and their inclination angles were simply calculated. The test results show that this method can easily and intuitively measure the tilting ability of rotary steerable drilling tools, meeting the evaluation of tilting ability for different drilling tool combinations; The deflection displacement at the steerable ribs and the lateral force at the drill bit have a significant impact on the tilting ability of the static push-the-bit rotary steerable drilling tool. Increasing the lateral force at the drill bit and increasing the eccentric displacement at the steerable ribs can effectively improve the tilting ability of the rotary steerable dirlling tool. The research results provide a theoretical basis for the optimization of rotary steerable drilling tool combinations and the evaluation of inclination ability.