FiberLine Technology


Through our business cooperation agreement with Well-SENSE, Wellbore Integrity Solutions offers FiberLine Intervention (FLI) tools and services globally for well abandonment and well integrity applications. With this FLI technology, WIS provides significant benefits to our customers for efficient planning, analysis, and execution of well abandonment, late-life, and wellbore remediation projects. The combination of FLI data acquisition and measurements, along with well abandonment and remediation tools, offers our customers an innovative, unique, and valuable solution.

Image courtesy of Well-SENSE

The FLI system uses fiber-optic technology to capture distributed temperature and acoustic measurements along the entire length of the well in real time. The data creates a rich well profile and can monitor changing conditions, irregularities, anomalies, or events to deliver greater insight across a wide range of applications.

When compared to other forms of well surveillance, costs and run times are dramatically reduced. Surveys can be completed in approximately two hours from arrival and only require one person at the wellsite. The equipment is hand-portable, compact, and lightweight with a tiny wellsite footprint. The FLI probe and fiber are single-use and sacrificial at the end of the survey.

The combination of WIS’s well abandonment and remedial tool portfolio and Well-SENSE’s FiberLine Intervention system offers our customers unique applications for P&A Surveys, Leak Detection, Cement Placement Assurance, Bottom-Hole Pressure and Temperature Surveys, and other applications available on request.

To find out more specific detail about FLI technology, visit the About FLI webpage from Well-SENSE.


FLI can be used to provide an in-depth analysis of the wellbore, optimizing the activities of the abandonment program. FLI provides insight into what is happening along the entire length of a wellbore providing information on what is happening behind the tubing, casing, and cement. Having this knowledge allows targeted abandonment solutions to be made by using our extensive P&A portfolio. This targeted approach reduces risk and associated costs. The ability to utilize FLI offline, as a stand-alone service, can provide the information that allows the optimal solutions to be chosen prior to mobilizing equipment and personnel and so reduce the uncertainty associated with the P&A process.


FLI surveys are much faster to carry out than multi-point stationary surveys, as the fiber is sensing along its entire length continuously. FLI is also faster to run and more sensitive than encapsulated fiber, providing more information in less time, even if any leaks are small and intermittent.

The differences can be dramatic. Leak detection jobs that may conventionally take days can be completed in a few hours, from rig-up to rig-down, sometimes with only a few minutes of surveying time.


Using FLI, dynamic distributed temperature measurements can provide rich information about the quality of a cement job at all points along the fiber, from just after the cement slurry is loaded into the casing annulus. FLI can provide a time-lapsed view of the exothermic curing process of the cement throughout the entire wellbore. Once the wellbore returns to its subsurface geothermal gradient, typically in about 24 hours, the profile can immediately be interpreted to provide information such as the top of cement and cement/fluid interfaces, density changes, and void areas. At the end of the job, the fiber is cut and the FLI probe is left in the well or drilled out.


An Active-FLI probe, equipped with a disposable electronic pressure/temperature gauge, is designed to provide short-term bottom hole measurements. It is especially useful in combination with other measurements, such as the DTS log taken during the descent, greatly enhancing the value of a dynamic survey. The information will verify a well’s static bottom hole temperature and pressure which is helpful for optimizing production, planning artificial lift or enhancing oil recovery (EOR) projects, and informing remediation and P&A operations.


FiberLine Intervention is also deployed by Well-SENSE in a wide range of other applications, servicing exploration, development, stimulation, and enhanced recovery in oil and gas wells. Additionally, this technology is increasingly used outside the oil and gas sector. For more information, please visit