The All Grating Fiber (AGF) technology of FBGS in combination with 4DSP’s Optical Sensing System can provide engineers with accurate, real-time data on the riser’s strain levels, its shape, and additional residual strains resulting from overloading. The combined optical sensing solution provides strain sensing using thousands of distributed sensors to ensure maximum coverage from a single lightweight optical fiber that is immune to EMF, RFI, or other electromagnetic influences.
Subsea applications such as “Riser Monitoring” have used engineering techniques and practices taken from the space flight and aerospace engineering domains. Both subsea and outer space environments demand high-value, mission critical components and systems where failure is not an option. In these environments, risk management dominates all other factors when designing components for reliable operation and predicting failure before it happens. The aerospace community has always known effective risk management is made possible by collecting more of the right data about the health of the system components. More data means more measurement points and more frequent measurements. Fiber optic sensors are the answer.
FBGS’s “All Grating Fiber” comprises densely spaced Draw Tower Gratings (DTGs) over the full length of an optical fiber, which enables more precise measurements over a wide strain or temperature range with more than 2000 sensing points per single optical fiber strand. This high number of sensor positions needs to be matched with an interrogator capable of high speed measurements such as 4DSP’s Optical Sensing System. The 4DSP interrogator was originally designed and deployed in space flight and aerospace applications. Now the All Gratings Fiber and the 4DSP Optical Sensing System are combined a solution providing unique performance for Subsea Riser Monitoring. This special combination enables the advanced collection of real-time tension, torsion, and shape information.
Subsea risers must withstand some of the most complex loads and harsh environments that systems have ever faced. The dynamic nature of ocean environment subjects the riser and all its structural components to rapidly changing stresses which result in fatigue, material wear, and mechanical degradation. Measuring these stresses to predict riser condition and health is highly challenging. It is critical that any sensor as a component integrated into a riser to monitor the riser’s structural health must be both responsive to these highly dynamic loads and robust enough to survive this tough environment.
Based on the highly distributed strain sensing using FBGS’s “All Grating Fiber” technology in combination with 4DSP’s Optical Sensing System, real-time monitoring of riser loads, shape, and performance can be monitored. Real-time monitoring also supports forensic engineering by storing data on actual events as they occur. This capability assists in determining the ‘how and why’ of an incident to prevent recurrence – a key element of risk management.
For more information about the capabilities of this combined solution, please contact FBGS.
