What is Coil Tubing, and what are its benefits?

Conventional tubing or drill pipes need to be connected and disconnected for tripping in the wellbore. Stands of 2 or 3 singles are lowered in the well for well intervention or drilling. Coil Tubing is a very long metal pipe spooled on a large reel and can be lowered into the well and pulled out just by winding and unwinding the pipe on the reel. Coil Tubing provides a cost-effective and time-efficient alternative to conventional straight tubing. A coil tubing unit can do many well interventions without mobilizing a workover rig. Coil tubing can be used for drilling or live well intervention as well.

Benefits of Coil Tubing:

  1. Continuous Operations: Since coil tubing is a continuous metal pipe, it does not need to be connected and disconnected like conventional pipes to lower or pull out of the well. This allows for continuity of operations.

  2. Efficient and Cost-Effective: Continuous pipe that can be lowered into the well by unwinding the reel makes the whole operation very time efficient. It reduces downtime and saves the overall cost of the well.

  3. Safety: Since the operations don’t need connecting and disconnecting pipe stands, a smaller crew is required on the rig floor. This reduces the exposure and risk of accidents by eliminating the need to operate many tools on the rig floor.

  4. Flexibility and Reach: Since coil tubing's stiffness is much less than that of drill pipe or tubing, it can navigate through complex and tortuous well trajectories that may be difficult to reach with conventional pipes. Since it is more rigid than a wireline, coil tubing can replace it for operations in high-deviation wells where the wireline cannot reach.

  5. Live Well Interventions: Coil tubing can be inserted and lowered into the well for intervention without killing a well, making it an effective and efficient well intervention option on live wells.

  6. Environmentally Friendly: Using coil tubing reduces the carbon footprint of operations by making them more efficient and reducing the number of days a rig may have to operate on a well to accomplish all objectives.

  7. Rigless Operations: In many instances, the operations can be carried out by deploying a coil tubing unit on the location, eliminating the need to mobilize a drilling or workover rig.