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about Fiber Bragg Gratings (FBG), FBG Sensors and Monitoring Systems

Distributed fiber optic sensors and their prospects

on June 1, 2020

pump-jack-848300_640Modern industrial systems are subject to increasingly strict requirements. Structural health monitoring must always work reliably regardless of environmental conditions. Observability and manageability become an important parameter. The operator must be able to detect a problem, including a potential one, determine the location of its occurrence, and respond in a timely manner, taking the necessary measures to reduce time and material costs in emergency situations.

Current fiber optic sensing technologies make it possible to continuously, accurately and in real-time detect small changes in temperature, acoustic background, and deformations in any place of an industrial facility. Fiber optic cables, which are traditionally used in the telecom industry for transmitting information, come to the rescue to perform this. Depending on the type of devices connected to the optical cable, it is possible to detect various environmental events at a long distance (up to several tens of kilometers) performing structural health monitoring. The sensitive medium is the optical fiber and a huge number of “virtual” sensors inside it.

DAS (Distributed Acoustic Sensing) are “virtual” microphones installed along with the optical fiber. Standard single-mode optical fiber and Rayleigh scattering are used when acoustic vibrations cause small changes in the refractive index that are detected using this scattering. The fiber literally “hears” events occurring in the environment. The number of DAS is a combination of spatial resolution, distance, and pulse duration. Modern distributed fiber optic sensors can operate at distances of up to 80 km. Combining several devices into a single network allows creating thousands of kilometers of structural health monitoring lines.

DTS (Distributed Temperature Sensing) is “virtual” thermometers along with the optical fiber. The distance range for a conventional single-mode fiber is up to 100 km with a spatial resolution of 1 to 5 meters and a measurement accuracy of less than 1 degree Celsius, with a measurement time of 2 to 30 minutes. These parameters are interdependent. For example, the longer the measurement time is, the better the spatial resolution and accuracy of the measurement are, and vice versa. 

Herewith, analytics show that the market for such distributed fiber optic sensors will grow by at least 10% per year in the foreseeable future. These fiber optic systems are most in-demand in North America. In terms of application, the oil and gas industry has the greatest potential. Temperature control prevails by type of monitoring.

Over the past 10 years, fiber optic sensing technology has been used to monitor thousands of kilometers of pipelines, thousands of oil and gas wells, and more. There are numerous fiber optic solutions that allow accelerating the introduction of promising technology in the industry, devices, and fiber optic cables are constantly being improved and become more accurate and affordable.

Optromix is a fast-growing vendor of fiber Bragg grating (FBG) product line such as fiber Bragg grating sensors, FBG interrogators and multiplexers, Distributed Acoustic Sensing (DAS) systems, Distributed Temperature Sensing (DTS) systems. The company creates and supplies a broad variety of fiber optic solutions for monitoring worldwide. If you are interested in structural health monitoring systems and want to learn more, please contact us at info@optromix.com

editorDistributed fiber optic sensors and their prospects

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