Control technique on navigating path of intersection between two horizontal wells

The intersection between two horizontal wells is a form of U-shape well. Being efficient, economical, advanced and environmentally friendly, it holds broad application prospects in exploitation of resources and crossing of pipe lines and tunnels under rivers. However, it is very difficult to achieve intersection between two horizontal wells by conventional techniques due to borehole position uncertainty. In order to solve this problem, control technique on navigating path was put forward. It mainly consists of position locating technique, profile design method, trajectory control method and relative position error analysis. Firstly, the measurement of relative position between the bit and the intersection point was carried out by RMRS in closed-loop mode rather than traditional open-loop mode. Then the profile of the intersection between two horizontal wells was designed according to the ranging scope of RMRS, guide process and borehole position uncertainty. After that the trajectory control model in the intersecting process was established on the basis of an analogy between the intersection of the two horizontal wells and the plane landing process. Finally, the relative position error analysis was carried out according to the guide process of RMRS. The development of control technique on navigating path make it more feasible to achieve intersection between two horizontal wells, which will have a great reference value for in-depth study and field application in the future.