Research On Fatigue Monitoring Method Of Carbon Fiber Fully Wound Cylinder With Aluminum Liner Based On Strain Gauge

With the widespread use of fiber-wound composite gas cylinders,due to its filling medium is mostly flammable and explosive,fiber-wound composite gas cylinders from time to time there are explosions and injuries and other safety accidents,its safety issues have also aroused people’s concern.Currently used detection and monitoring methods have their own advantages,but most of them have certain requirements for working conditions,cylinder scale size,or require special testing instruments and equipment,not suitable for the widespread use of the practical operation is not good.In view of the limitations of the existing testing methods for fiber-wound composite gas cylinders,taking the aluminum liner carbon fiber fully-wound gas cylinders as the research object,a fatigue monitoring method for aluminum liner carbon fiber fully-wound gas cylinders based on strain gauges is proposed in the article,and the main research contents are.(1)The fatigue process of aluminum liner carbon fiber fully wound gas cylinders is analyzed,and considering the possible strain changes on the surface of fiber wound composite gas cylinders in the late stage of fatigue,the method of fatigue monitoring of fiber wound composite gas cylinders using strain gauges is proposed in combination with the universality of strain monitoring.And based on this,the test design was carried out,and then suitable test materials and test equipment were selected to build the experimental platform for fatigue monitoring test,and through the collection of monitoring data during the actual test,it was proved that the monitoring system could operate successfully.(2)After the test,the collected data of the test were pre-processed and combined with the application of strain gauges on concrete structures such as bridges and buildings,it was judged that the main factor affecting the results of this test was the change of temperature.The separation of the temperature effect using regression analysis was proposed,and by comparing the data before and after the separation of the temperature effect,it was proved that the separation of the temperature effect had no effect on the key factors in the original data,and the test data that could truly reflect the change of the carbon fiber fully wound gas cylinder with aluminum liner was obtained.Then,by processing and analyzing the peak-to-peak values of the test data,the stiffness degradation of the composite layer was determined,and the theoretical The fatigue monitoring test using strain gauges was validated by mirroring the theoretical analysis in the previous section.(3)In order to further determine the test results,the damage of the fatigued aluminum liner carbon fiber fully wound gas cylinders was detected by using CT inspection and penetration inspection.and the feasibility of the strain gauge monitoring method.Meanwhile,in order to investigate the actual effect of fatigue monitoring with strain gauges under different pressure conditions,a fatigue test with the same size cylinder and strain gauges was conducted under the maximum pressure condition of 33.4 MPa,and the test results showed that the upper pressure limit of the fatigue pressure test would lead to early cracking of the surface matrix of the carbon fiber fully wound cylinder with aluminum liner and affect the actual monitoring effect.