Coiled tubing was developed in 1970s and is one of the most important pieces of well intervention equipment in the oil and gas industry. There are several different types of it available in the industry market with several different designs of a coiled tubing unit; however, the components of a coiled tubing unit are very similar. The main differences are performance capabilities and hydraulic power control systems. This article will give an overview of the essential components of a coiled tubing unit. (Read about the history of coiled tubing here – Introduction to Coiled Tubing (CT) in Oil and Gas)
Figure 1 shows the mounted truck coiled tubing unit, which is normally used for the land operation and Figure 2 is the coiled tubing unit used for operating in an offshore environment.
Figure 1 – Coiled Tubing Unit on a Truck (Courtesy of Stewart & Stevenson)
Figure 2 – Offshore Coiled Tubing Unit (Courtesy of NOV)
Development of the coiled tubing like we know it today started in early 1960’s. Now it is an important component of various workover and service applications. While still the use of Coil Tubing is about 75% in workover/service applications, the technical advancements have resulted in an increase in utilization of Coil tubing in drilling as well as completion applications.
Ability of performing remedial work on live well was an important driver associated with development of Coil Tubing. In order to achieve this feat, there was a need to overcome three different technical challenges: These were:
- Continuous conduit that is capable of being inserted in to wellbore (the CT string).
- Means of running the CT string and retrieving it in to or out of wellbore when under pressure (the injector head).
- Device that is capable of giving a dynamic seal around tubing string (packoff or stripper device)
Coiled Tubing Unit (Credit: ShutterStock)
The Origin of Coiled Tubing Continue reading