The Vector Magnetics Rotating Magnet Ranging Service uses the rotation of a magnetized bit sub behind the bit in the drilling well to create a time-varying magnetic field that can be detected more than 60 meters away in a second well. A wireline tool with tri-axial accelerometers and multi-frequency magnetometers in a second well measures the magnetic field magnitude and orientation. The measurements correlate to the depth in the drilling well. Typical applications are measuring and controlling well bore separation or for homing-in to intersect and join wellbores in various geometries.

The RMRS system has been used for over 1000 Coal Bed Methane (CBM) horizontal to vertical intersections.  In this application the magnetic bit sub is located directly behind the drill bit and the receiver on wireline in the target well. Accurate position information can be acquired at more than 150 feet of lateral separation, allowing for significant trajectory correction prior to intersection. Intersecting targets ranging from 4.5 inch casing to 6 foot diameter cavities is routine.