Coiled Tubing Drilling (CTD) has been used effectively for over 20 years in the oil industry and the technology has been evolving in order to meet changing industry demands. CTD takes the well-established concept of Coiled tubing and combines it with directional drilling using a mud motor to create a system for drilling reservoirs. Bottom hole assemblies (BHAs) are now able to drill directional, S-curve and horizontal wells and can be the key to unlocking reserves in mature oilfields via re-entry drilling. Coiled tubing drilling is known for its speed and ability to drill reservoirs in anunderbalanced condition and CTD can reduce drilling times between 30%-60% compared with conventional jointed pipe drilling rigs. Therefore CTD can provide significant economic benefits.
Coiled Tubing Drilling is a modern drilling technique that combines the concepts of coiled tubing and directional drilling using a mud motor that creates a system for drilling reservoirs. This technique is advantageous as it requires less effort to trip in and out from the well. This technique allows continuous pumping and drilling and increases the rate of penetration in underbalanced conditions. Coiled Tubing Drilling is known for its speed and efficiency to drill reservoirs in imbalanced conditions and provide economic benefits.
Coiled Tubing Drilling uses coiled tubing rather than conventional drill pipe. This provides an advantage of putting less effort as the coil can easily run in and out whereas the drill pipe is required to be assembled and dismantled joint-by-joint during trip in and out. The technique is advantageous as it uses coiled tubing that enters the hole through a stripper, seated on the injector which provides hydraulic seal around the coil.
Coiled Tubing Drilling provides well controlled capabilities beyond those possible with drill pipe and also allows drilling in underbalanced conditions. The technique uses a mud motor to rotate the drill bit instead of a top drive or rotary table at the surface. It has fewer impacts on the environment as it reduces human interaction, well footprint, noise pollution and discharges.