This paper explores four unique case studies where a novel limited-access ranging system was used in real world examples of well placement with close-proximity drilling applications. The case studies highlight enhanced recovery and reduced complexity for the overall well construction process. The method uses a gradient ranging system along with surface excitation to create an active magnetic field along the target wellbore to acquire a distance and direction measurement. This arrangement eliminates the need for the typical access-dependent ranging conveyance using coiled tubing or wireline systems. With this approach, several logistical and technical constraints are removed, making several unique solutions possible, such as ranging to abandoned wells and to wells with casing damage or other obstructions, and as well as high-temperature applications as no intervention is required to the target wellbore.
The first case study used magnetic ranging to an abandoned wellbore in an approach similar to drilling a standard Steam Assisted Gravity Drainage (SAGD) injector well. The second study highlights an anti-collision scenario which required toe-to-heel ranging to an abandoned wellbore. The third used magnetic ranging as an anti-collision tool performing toe-to-heel ranging to a currently producing wellbore where completion tools were left in the hole. The fourth scenario used the technology to drill a parallel well where a casing and tubing obstruction limited the ability to run traditional ranging equipment.
Through this paper, the authors will illustrate the benefits of this technology in their use in Steam Assisted Gravity Drainage drilling applications and expand on potential benefits of this technology in other close-proximity drilling applications for either paralleling or anti-collision purposes.