Method for detecting bolt fastening joint surface pressure based on FBG sensor

Abstract

The invention belongs to the technical field of pressure detection of a connecting piece joint surface, and provides a method for detecting a bolt fastening joint surface pressure based on an FBG sensor, wherein the method converts the joint surface pressure to the strain of the FBG sensor. The method comprises the steps of: determining the size and the position of the embedding groove of the FBGsensor based on a strain transferring theory of embedded FBG sensor; and determining the pressure of the detecting point of the joint surface based on a single-bolt connection joint surface pressure distribution theory, thereby realizing the calibration of the strain and the pressure value corresponding to each other, and realizing the accurate detection of the joint surface pressure. According tothe method for detecting the bolt fastening joint surface pressure based on the FBG sensor, the method determines the size and the position of the embedding groove of the FBG sensor, thereby ensuringthe reliability and the accuracy of the strain information, obtaining an accurate strain-joining surface pressure curve combined with the determination of the joint surface pressure, and providing apractical and feasible method for studying bolt connection joint surface pressure.

Description

technical field [0001] The invention belongs to the technical field of joint surface pressure detection of connectors, and specifically relates to a method for indirectly reflecting the joint surface pressure by detecting the strain of the joint surface by an FBG sensor. Background technique [0002] In the assembly of major engineering equipment parts and high-precision parts, bolted connections are often used, but it has been difficult to accurately control the bolt pretightening force and the pressure of the connection joint surface, the pressure control on the joint surface is inaccurate, and the pressure on the joint surface after installation Uneven distribution will seriously affect the stiffness of the connection and the overall performance of the equipment. In the assembly of major equipment, such as high-pressure and low-pressure turbine shafts in aero-engines, high-pressure compressor discs and drums, there are a large number of bolt connections, and the connection...

AI Technical Summary

Problems solved by technology

[0004] Aiming at the disadvantages of the above detection methods, the present invention proposes a new and reliable method for detecting the joint surface pressure. Because ultrasonic detection is easily interfered by external factors, the detection accuracy is low, and external factors such as noise have little influence on the detection of FBG sensors. , and it directly detects the magnitude of the strain, with high precision, which greatly improves the detection accuracy; after using this inventive method for calibration, the specific value of the joint surface pressure can be effectively detected with minimal damage to the joint surface , avoiding the disadvantages of embedding pressure sensors at the joint surface, so this method has strong practical value

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