Research on Optimal Design of Bottom Hole Assembly of Directional Well in Gadin-North Gadin Gas Field

Aiming at the problems such as difficulty in controlling well trajectory and easy occurrence of complex downhole accidents in directional deviation operation in salt-paste interbed of directional deviation well in Gadin-North Gadine gas field, position characteristic model and curvature calculation model are established by optimizing parameters affecting the performance of drill assembly, and the size and length of screw, drill collar and centralizer are analyzed and studied. The results show that the screw diameter and the centralizer diameter have a significant influence on the inclination building ability, and the change of drill collar length and drill collar diameter has a gentle influence on the inclination building ability. By adjusting the drill assembly size, the well inclination Angle can be optimized by 0.31°/30 m and 0.23°/30 m, respectively. The optimal result of the BHA provides the BHA optimization idea for the subsequent directional well drilling operation construction of the gas field, and better exploration and development.