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High temperature pressure piping have been applied widely in the chemical
industry, the petroleum enterprises and the electrical power plants, and corresponding
accidents happened frequently every year owing to the pipeline leakage and explosion. By
massive accident statistics and analysis, the high temperature creep and the pipeline inside
wall corroding are the main causes to result in the pipeline leakage and explosion accident.
By real time sensing the strain change of pipeline outer surface, the online working status of
the high temperature pipeline could be monitored and the leakage and explosion accidents
would be avoided.
Now several methods can be considered to sensing and monitoring the strain change of
the high temperature pipeline surface, including Electricity sensor examination method,
ultrasonic wave examination method and infrared thermal imagery examination method. After
careful analysis and contrast, Electricity sensor examination method was given up for it
couldn't be working steadily under high temperature conditions and easily excitated electric
sparks which would result in flammable explosive danger in chemical industry and petroleum
enterprises. Ultrasonic wave examination method and infrared thermal imagery examination
method could avoid the shortages of Electricity sensor examination method based on the
non-destructive examination theory, but the ultrasonic wave method could be applied only in
examining the pipeline wall thickness, the inside wall crack as well as the material air bubble
flaws restricted in its working principle. Consequently ultrasonic wave method examination
method wasn't suitable to sense and monitor the strain change of the high temperature
pipeline surface; Infrared thermal imagery examination method has low sensing resolution
and can only examine internal etching pit and wall thickness attenuating, so it is unable to
examine the pipeline surface strain change on time. Therefore three reported real-time
examination methods mentioned above cannot satisfy the strain change monitoring of high
temperature pressure piping. In this paper a novel method is presented using optical Fiber
Bragg Grating sensor to carry on the real-time monitoring of the high temperature pressure
piping surface strain change. firstly the stress and strain analysis of the high temperature
pressure piping surface is given based on the established theoretical model, then optimized
design and simulation is accomplished with computer ANSYS software. In the end a
optimized set-up is put forward and discussed.
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