Land Based Rigs 65 4000 HP drilling rig National Oilwell is the world leader for innovative land based rig packages with designs pioneered to include highly mobile slim hole drilling rigs, single module pad drilling rigs for the north slope of Alaska, mechanized rigs, modular desert rigs, track-mounted swamp rigs and helicopter transportable rigs. National Oilwell has the experience and capabilities to design and fabricate advanced rig packages for any climate or terrain conditions, considering different parameters. Semi-automated drilling rigs Small footprint minimum lease design