Abstract
To ensure the effective well trajectory in the oil zone, the horizontal section of the bTHW 404 well luctuates with the oil zone to make through six target points, and the well trajectory shapes like a “ish hook”. The dificulties in the well are as follows: the oil zone is thin, the target window is small, there are 6 targets points, and thus the controlling accuracy of the trajectory is required high, the horizontal section luctuates, the friction between drilling pipe and hole wall is high and the vertical depth is shallow, thus it is dificult to get enough WOB (weight on boat), the vertical depth of the start point horizontally is the smallest where the cutting bed inluences the pipe or liner running-in. During operation, multiple measures are adopted to ensure the secure running-in of slotted liner, such as the exact control of well trajectory, the optimization of drilling tool structure and parameters. It only spends 53 hours on fulilling the drilling in horizontal sections and the running of liner in the well, providing good reference to similar projects.