Dual drill pipe — A new approach to drilling

The idea for a new drilling method was born at Rogaland Research, now the International Research Institute of Stavanger (IRIS) in Stavanger, Norway. The idea was motivated by the challenges of solving hole cleaning and weight-on-bit control for coiled tubing drilling applications. After a feasibility study, the method was refined and found applicable to solve several challenges for jointed pipe drilling as well. The patented Reelwell Drilling Method showed unique features for the following applications: * Managed pressure drilling: Pipe connections can be performed at constant downhole pressure without any shut-in pressure at surface using a downhole valve. * Liner drilling: A liner can be installed in the same run, while a new section is being drilled. Also, there is an option to expand the liner in the same run. * Deepwater drilling: Return fluid is transported back to surface through the drillstring, enabling advanced gradients of the annular well fluid.