Technology Focus: Coiled Tubing (June 2024)
Authors: Ramondenc Pierre 
Published: June 2024

What a year 2023 has been for the well-intervention business! Despite all the debates on the energy transition, oil and gas demand continues to be strong and all the actors of our business look for avenues to increase hydrocarbon recovery and enhance production at minimal financial and environmental costs. The year 2024 builds on this momentum and looks at least as promising.
As was discussed last year, coiled tubing has a key role to play in those efforts, thanks to several technology advancements and best practices that deliver safer, leaner, and more-efficient operations. Those three themes were once again at the center of discussions at the 2024 SPE/ICoTA Well Intervention Conference and Exhibition (WICE) in The Woodlands, TX, USA, on 19–20 March. Coiled tubing benefited from great visibility, judging from most of the presentations of the technical program. The event focused on the usual themes, such as interventions in horizontal and multilateral wells, wellbore integrity, advancements in downhole tools, surface equipment and other materials, or even offshore operations. But what was particularly interesting to me was the renewed excitement surrounding light well-intervention vessels and subsea interventions, digital enablement, and coiled tubing drilling (CTD).
As you may remember, CTD was already part of our technology focus in 2023. In fact, it is not the first time it has been given the spotlight in this column. With a quick look at previous issues written by my esteemed predecessors, the reader will realize that, like the phoenix being reborn from its ashes, CTD comes and goes in cycles. However, this time around, it seems to be at the forefront to stay, being considered strategic by an industry in search for economical ways to reach bypassed reserves at a time when hydrocarbons become more and more complex to find and extract. Those privileged to have attended the 2024 International Petroleum Conference on 12–14 February in Dhahran, Saudi Arabia, certainly noticed how CTD is already heavily used in the Middle East and the North Sea. Those success stories have (re-)sparked new interest in Asia, the Caspian Sea, and North Africa, just to name a few. Sieving through the long list of coiled tubing publications since our last review, the reader will come across no less than a dozen major papers written on the topic (and I am sure I may have missed some). A glimpse at how CTD is making a difference in the recovery strategy of some operators despite the complexity of those projects can be found in papers IPTC 23188 and SPE 216909. While the former highlights
the importance of data and how to properly interconnect it for the success of those drilling campaigns, the later details the methodology by which one can drill new laterals in underbalanced conditions to unlock depressed reservoirs.
Reducing the world of coiled tubing to CTD would, however, be a mistake. Several papers presented at the SPE/ICoTA WICE are there to remind us of the wealth of applications that continuous development of downhole tools and engineering practices has enabled for the past four decades. Coiled tubing is much more than fluid or tool conveyance; today, it offers rigless alternatives to workscopes that could only be envisioned with workover rigs a few years ago. For instance, SPE 214144 shows how it is now possible to temporarily suspend a well thanks to an ingenious workflow using inflatable packers, thus speeding up well integrity remediation while significantly reducing logistics and environmental footprint. SPE 218365, awarded the outstanding paper award at the SPE/ICoTA WICE, provides many details on how to combine tools and practices that belong to the wireline, slickline, perforating, and coiled tubing worlds, all in one run, for a record-breaking perforating operation. All those advances—and many others—would not be possible without improvements in our understanding of materials, how to protect coiled tubing pipes, how to get the best performance out of them under downhole conditions that are becoming every day more extreme, and how to preserve wellbore completion at the same time. Papers SPE 218327 and SPE 218335 also are perfect examples of those efforts and pave the way to safer operations in the years to come.
Recommended additional reading at OnePetro: www.onepetro.org.
SPE 216909 Preparation, Execution, and Associated Challenges for Using the First Successful Closed-Loop-System Methodology Worldwide in Underbalanced Coiled Tubing Drilling in ADNOC’s Fields by Mohamed Osama, ADNOC, et al.
SPE 214144 A Pioneer Step in Restoring Well Integrity for Workover Rig Intervention Through Instrumented Coiled Tubing and Through-Tubing Inflatable Packer by Omar Abdulrazzaq Hamadah, Kuwait Oil Company, et al.
SPE 218335 Understanding Mechanisms of Wellbore Abrasion During Coiled Tubing Intervention by Jesus Campos, SLB, et al.