Publications

Wireline logging data acquisitions in Coal Bed Methane wells can be very challenging due to difficult borehole condition. Bridging events due to ledges, wash outs, swelling, sloughing formations etc are common problems that can occur on a traditional wireline logging operation. Even a single bridging event can consume twice as much time as a normal logging run without bridging. In a multi layer coal seam well, the risk of bridging events is proportional to the number of coal seams in the well. Out of pipe logging or also known as thru drillpipe logging is a wireline conveyance technique that can be used when well restrictions or ther obstructions render traditional wireline operations problematic or even impossible. The technique involves lowering open-ended drillpipe into the well past the restriction or zone of difficulty. The logging tools are then lowered through the drillpipe into open hole to acquire data in the zone of interest. In wells with multiple restrictions, the drillpipe can be repositioned to ensure data is acquired over the entire zone of interest. The use of this procedure significantly increases the ability to reach TD with logging tools and thus improves the efficiency in acquiring the necessary formation evaluation data to fully evaluate the well. Recent wireline logging operation in Indonesia have demonstrated that by using this out of pipe method it is possible to consistently acquire logging data in difficult well by eliminating incomplete wireline logging operations, reduce time used for well conditioning trips with the added benefit of improved safety as the rig can circulate and reciprocate during the logging operation.