Efficient Deployment of Distributed Temperature and Acoustic Sensing of Three Wells Using Fiberline Intervention Technology

Abstract

Abstract Fiber optics has been an emerging technology in the oil industry as it provides critical downhole data from the well. However, running fiber in the well has been mainly limited to new constructions or through costly coiled tubing operation. This paper describes a novel method to deploy fiber in existing wells and collect distributed and single-point data. This was demonstrated through a successful and low-cost logging operation. FiberLine Intervention (FLI) employs a unique conveyance method to deploy the fiber inside the well. Two fibers (single-mode and multi-mode) with total length of more than 25,000ft have been wound inside a tool length of around 3ft, which can then unspool from the tool as it drops down the well by gravity. The tool utilizes bare optical fiber and housing materials that will degrade in the well, so it does not disturb production after completing the job. The end of the fiber is equipped with an electronic gauge to measure single point pressure while the fiber itself can be interrogated to provide Distributed Temperature Sensing (DTS) and Distributed Acoustic Sensing (DAS) data. Real-time data monitoring capability is enabled by connecting the top of the fiber to a surface laser box. Normal practice to deploy sensing and monitoring logging tools is to use slickline or wireline. Operational costs and time are of particular concerns, especially when there is a need to bring rigging equipment. Regarding this matter, FLI technology surpassed the conventional slickline by consuming only 15 minutes from releasing the electronic probe to reach the hold-up depth. During this time, DTS, DAS, pressure and temperature data were recorded in real-time. The location of the tool could be confirmed by the fiber loss plot, which shows excessive losses in the still spooled fiber within the probe, and normal losses in the fiber deployed in the wellbore. After the tool has reached the target depth, the annuli were bled of and the DAS responses were monitored to check for any leak in the completion. The presented field trial represents a successful logging operation, starting from tools setup to the data quality. This breakthrough could be viewed as a starting point as further developments can consider using this as a platform to deploy more variety of sensors downhole.