The Fiber Optic Sensing Association (FOSA), the world’s premier trade association for distributed fiber optic sensing (DFOS), today released FOSA Installation Considerations for Pipelines, which contains guidance on the selection and positioning of fiber optic cables to maximize the benefits of DFOS along pipelines. Fiber optic sensing is an emerging and key technology for advancements in the safe and efficient operation of pipelines throughout the world.
“As the market learns of the benefits provided by distributed fiber optic sensing, a natural extension is to ask about the make-up and installation of installed sensing solutions,” said Dr. Chris Minto, FOSA Technology Committee Chairman. “This document provides a primer for those considering adoption of this capable technology to advance the operation and safety of their pipeline assets.”
FOSA Installation Considerations for Pipelines is intended to support common uses of DFOS in real-time monitoring of pipelines, including:
- Detection of unauthorized (or unexpected) third party interference near the pipeline for damage prevention
- Detection of pipeline product leaks, whether liquid, gas or a combination of liquid and gas
- Detection of critical temperature changes along pipelines
- Complementing internal inspection methods by tracking the position of instrumentation and cleaning PIGs (Pipeline Inspection Gauges
- Detection of excessive environmental strain to pipelines resulting from shifts in the soil caused by subsidence, landslides and other geotechnical reasons
The document addresses three of the primary DFOS technologies that are often used in monitoring pipelines, each providing unique insights into the operational characteristics, asset health, and environmental conditions of the pipeline:
- Distributed Acoustic Sensing (DAS) is used to sense both leaks and third party intrusion by monitoring vibrations near the pipeline.
- Distributed Temperature Sensing (DTS) is deployed to monitor the subtle temperature variations that occur from product escaping from the pipeline. Release of high-pressure gas will lower the surround temperature due to the sudden reduction in pressure as it leaves the pipeline, where oil typically increases the surrounding temperature, as it typically has a higher temperature than the surrounding soil.
- Distributed Strain Sensing (DSS) is deployed along or on the pipelines to monitor changes in strain that might be caused by shifts in the soil near the pipeline. If the strain from these soil shifts gets large enough, it could cause the pipeline to shift, possibly buckle and maybe even break, allowing product to escape.