Coiled tubing

Coiled Tubing-2021

In previous features, the focus has been on what is new or reimagined. Therefore, I thought that, in selecting papers for this year’s feature, it would be useful to select ones that look at coiled tubing operations performed and that have been evaluated in one way or another.

Coiled Tubing on a wheel

Last year, this feature opened, almost inevitably, with comments on the effects the COVID-19 pandemic might have on our industry. Unfortunately, a year later, we probably have all experienced the effects, both personal and work-related.

One of these effects is that there has been re-evaluation of what’s important. To understand what is important takes some reflection and evaluation of the past. In previous features, the focus has been on what is new or reimagined. Therefore, I thought that, in selecting papers for this year’s feature, it would be useful to select ones that look at coiled tubing operations performed and that have been evaluated in one way or another.

From Bolivia comes a paper that reviews some 25 well interventions performed. Most of these operations are of a type that will be familiar to the reader. Also, some of the challenges that were faced in performing these coiled tubing operations will be familiar. These operations used a range of established types of coiled tubing operations and blended the techniques to meet particular operating conditions, especially location and logistics challenges. All conclusions and best practices that resulted, however, may not be familiar to all readers.

During the past few years, many coiled tubing papers have focused on the use of coiled tubing in multizone fracturing operations, especially plug milling. An area of coiled tubing use in fracturing operations that has had less of an audience recently has been the use of coiled tubing in annular fracturing operations. This activity is still routinely being performed, particularly in Canada. The question has long existed about how the pipe is being eroded. In the related paper in this feature, the authors explain how they have tried to answer that question and have shared some of their review insights.

In the past decade, coiled tubing size, weight, and grade all have continued to increase. Looking back at this trend and thinking about its effect on pressure control equipment led the developers in the third of this year’s papers to work on solutions for shear rams. This is particularly relevant after having just passed the 11th anniversary of the tragic Macondo disaster.

Again, this year, I ask everyone to stay well.

This Month’s Technical Papers

Low-Force Shear Blades Developed for High-Strength Coiled Tubing

Customized Solutions for Coiled Tubing Interventions in the Bolivian Sub-Andean Basin

Best Practices for Avoiding Erosion in Annular Fracturing

Recommended Additional Reading

OTC 30408 Design and Safety Considerations To Perform Coiled Tubing Operations in Large-Diameter, High-Temperature Geothermal Wells by Ishaan Singh, Schlumberger, et al.

SPE 204446 Implementing Business Analytics Software To Optimize Coiled Tubing Operations: A Digital Approach to Operations Efficiency by Xaymaca Bautista AlarcoOTC 30408aks Energy Services, et al.

SPE 203272 The Reinvention of a Well-Established Coiled Tubing Intervention Work Flow Creates New Perspectives for Acidizing Openhole Horizontal Tight Carbonate Water Injectors by Sameer Punnapala, ADNOC, et al.


Alex Crabtree, SPE, is a principal engineer with Oceaneering International based in Houston. He has more than 38 years of experience in the upstream oil and gas industry. Crabtree holds a BS degree in mechanical engineering. He has worked in Southeast Asia, the Middle East, Europe, North America, and South America, both onshore and offshore. Crabtree previously worked with an exploration and production operating company and within the oilfield-services-company sector, holding various engineering and management posts in research and development, field operations, downhole-tool design, and technology implementation. He has authored several SPE papers and is a past program-committee chairperson for various SPE conferences and SPE Applied Technology Workshops. Crabtree is the chairperson for the SPE Well Integrity Technical Section, was an SPE Distinguished Lecturer in 2001–02, and is a member of the JPT Editorial Review Committee.