What is the history of coiled tubing drilling?
The origins of coiled tubing date back to 1934 when a patent was awarded for a “Reelable drill pipe well boring machine” In 1951 a patent was awarded for a reeled, rigid-pipe drilling system, which modern-day steel CT technology is still based on. The first CT drill rig entered service in 1962, by the California Oil Co. & Bowen Tools.
How does coiled tubing drilling differ from conventional drilling?
As opposed to a traditional drilling rig, there are no rods, these are placed by a continuous length of steel tubing that is wound around a large reel and then injected into the existing well casing to be deployed downhole. Coiled tubing drilling (CTD), utilizes a downhole motor for increased bit speeds and reduced weight on the bit compared to traditional drilling methods. Directional wells employing CTD require a steering assembly to control the trajectory of the well. CTD is applicable in both overbalance and underbalance drilling scenarios.
What are the advantages of coiled tubing drilling?
Coiled tubing drilling uses a continuous length of steel tubing that is wound around a large reel and then injected into the existing well casing to be deployed downhole. There The history of this technique dates back to the early 1900s and has garnered attention over the past 20 years, demonstrating several distinct benefits over conventional drilling. One of the most significant advantages is the ability to drill continuously in underbalanced conditions, protecting the integrity of the well formation and increasing drilling rate, especially beneficial for sensitive reservoirs. Additionally, coiled tubing drilling offers benefits in managing surface pressure, faster mobilisation speed, reduced rig time, and fewer preparation requirements, all leading to significantly reduced operational costs.
