Well path design and control of the first double branch well AZNN-022 in Iran North Azadegan Oilfield

Iran north Azadegan Oilfield entered integrated development stage in 2011, and a number of horizontal wells have been drilled targeted at Savark 3. The average depth of the drilled horizontal wells is over 4 000 m, and average drilling period was over 3 months. In order to improve oil recovery of single wells and shorten drilling period, the first double branch well AZNN-022 was planned. The final zone of the holes of this branch well is different from the target of the main hole, and its horizontal offset is short, its curvature is designed as high and it is difficult to prevent collision during drilling. This paper successfully addressed the above difficulty by optimizing the window cutting location, optimized trajectory design, accurate control of the trajectory, and anti-collision scan. The branch holes were successfully drilled and downhole safety was realized. This is of great guidance significance to subsequent drilling of double branch wells and sidetracking drilling in the deviated hole.