Most fiber Bragg grating (FBG) sensors are stable and robust in wet, corrosive and high EMI environments, and many work well over a broad range of temperature, e.g., -200 to +275 °C. But above 300 °C, the fiber coating materials, and the FBGs themselves, are subject to degradation and failure.

So what can be done at high temperature? I’ve written earlier about development of special gratings that can measure temperature to 1000 °C, but we’ve seen nothing for measuring strain at high temperature — until now.

Mercury Sensor Systems, LLC of Austin, Texas has recently developed just such a sensor called the Vulcan 1100. Using the Micron Optics’ standard os3120 strain gage as the base sensing element, Mercury’s patented special mounting system allows the FBG in the os3120 to operate below 200 °C while precisely transferring the strain to the FBG. A second FBG sensor (a Micron Optics os4210), integrated in the same package with the strain gage provides active temperature compensation. The Vulcan’s rugged package makes it ideal for its target applications in petroleum and chemical processing.

Find details at (http://www.mercurysensor.com/) or contact Pat Doggett at patrick.doggett@mercurysensor.com.