WorldOil

Drilling development wells in less time with lower cost

Determining the criteria for choosing between a motor/ VGS combination and RSS when drilling extended-reach wells. North Sea and GOM operators were early leaders in the adoption of Rotary Steerable Systems (RSS) when the tools entered the market in the late nineties. Increasing rig costs and the need to reach ever more complex targets were the driving forces behind this adoption. However, with announced deepwater rig dayrates already topping $500,000 in 2006, it appears that downhole reliability is playing an increasing role in the drive to reducing drilling costs. There is no doubt that when a RSS works well, it drills a smooth hole. Similarly, there is little doubt that when the well path needs complex geometry, it may not be possible to make the necessary turns without an RSS. But, what happens when that same RSS tool has to be pulled because the complex electronic package has failed...