A new electromagnetic beacon tool for directional drilling in steam assisted gravity drainage horizontal wells

Abstract

Steam assisted gravity drainage (SAGD) wells require precise separation between the production well and the injection well to ensure the efficient oil drainage of the reservoir. The precise measurement of the distance and direction between the being drilled injection horizontal well and the cased production horizontal well is needed during the SAGD drilling process. This high accuracy downhole surveying is achieved through the use of active magnetic ranging method. Based on this method, a new electromagnetic beacon tool has been invented with the purpose of simplifying the process of the drilling operation and reducing the cost in SAGD projects. A solenoid has been integrated into the beacon as the electromagnetic field source and an “H bridge” circuit has also been designed for alternating the direction of the current in the solenoid. Besides, a telecommunication circuit was designed and configured in the beacon to receive wireless signal. Deployed as the electromagnetic field source in the cased production well, the beacon can induced electromagnetic field for guiding the directional drilling trajectory along a path parallel to the existing production SAGD horizontal well. The electromagnetic beacon tool has a successful experiment in the “shallow well”. It can guide the directional drilling process in SAGD horizontal wells and make it possible to drill the injection SAGD horizontal well without any access to the production well.