A drilling technique that uses a continuous length of steel or composite pipe wound on a large reel, eliminating the need for traditional pipe connections during tripping operations. Coiled tubing typically ranges from 1 to 3.5 inches in diameter and can extend to depths of 15,000+ feet, enabling rapid deployment and retrieval compared to conventional jointed drill pipe. The continuous nature of coiled tubing allows for efficient operations in underbalanced drilling, well interventions, and re-entry drilling applications.

The primary advantage of coiled tubing drilling is the elimination of pipe connections, which dramatically reduces tripping time and associated non-productive time. The coiled tubing injector mechanism continuously feeds pipe into the wellbore while maintaining well control, enabling drilling and circulation without stopping for connections. This proves especially valuable for underbalanced drilling operations where maintaining precise wellbore pressure is critical, and for situations requiring frequent trips like short-radius lateral drilling or through-tubing operations in existing wells.