Research On Stress Sensing Technology Of Cold Rolled Strip Based On Fiber Bragg Grating

With the development of modern industry,cold-rolled strip is widely used in locomotive and vehicle manufacturing,aviation rocket,light industry food,electronic instrument and other industrial sectors owing to its good surface quality,excellent mechanical performance and technological performance.Due to the technical blockade and monopoly,the design and manufacturing technology of the shape meter have not been imported from abroad,and the demand for the shape meter has been dependent on imports up to now.This thesis proposes a scheme to replace the traditional shape measuring instrument with the fiber Bragg grating stress sensor,in order to solve the problems of low accuracy,poor anti-interference ability and high maintenance cost in the later period.According to the above content,this thesis carries out the following theoretical analysis and experimental testing.Firstly,the development of cold rolled strip steel shape detection technology and fiber Bragg grating stress sensor technology is discussed.Based on the discussion,the project of applying fiber Bragg grating sensing technology to shape detector is proposed.Secondly,the stress and temperature sensing models of fiber Bragg grating are analyzed in theory,and a metal encapsulated fiber Bragg grating sensing unit is designed,the latter is the key element of the new type of plate shape detector.Thirdly,the finite element analysis software is employed to analyze the model of the metal encapsulated sensor unit.Then,the stress and temperature simulation analysis is carried out to determine the stress and temperature characteristic parameters of the encapsulated sensor unit material.Further,the stress and temperature response characteristic of the encapsulated fiber Bragg grating sensor unit is clarified.Finally,the stress sensing unit based on fiber Bragg grating is designed and manufactured,and the temperature and pressure characteristics of the stress sensing unit are experimentally studied.The theoretical model and simulation results are verified by the experimental.Aiming at the low accuracy,slow response speed and poor anti-interference abilityof cold-rolled shape detection technology,a scheme of using fiber Bragg grating stress sensing technology to design basic stress detection element is proposed in this thesis.The key basic research of the design scheme is carried out from the theoretical analysis and experimental detection.The research results have important theoretical significance and practical reference value for the design of the new type of optical cold-rolled plate shape detector.