Research on crimping parameters of civil aircraft hydraulic pipeline and analysis of its high pressure vibration characteristics
The crimping repair parameters of four specifications of hydraulic pipelines were studied,and their dynamic characteristics under three pressure levels were analyzed.Firstly,the finite element model of the hydraulic pipeline after crimping repair was established.The modal analysis of the pipeline showed that when the crimping gap was 0 mm,the natural frequencies of each order of the pipeline did not change significantly with the crimping length.Within the frequency range of 0-1 580 Hz,the maximum normal stress value withstood by the pipeline decreased with the increase of pipeline diameter.Therefore,the crimping clearance of the four specifications of hydraulic pipelines should be 0 mm,and the crimping length should be determined according to the aircraft maintenance manual.The dynamic characteristics of four specifications of hydraulic pipelines were analyzed under three pressure levels.The natural frequencies of each order of the pipeline increased with the increasing pressure.The maximum deformation was less than 5 mm under three pressure levels.The equivalent stress of pipeline with outer diameter of 6.35 mm under 35 MPa was much greater than that under 21 MPa and 28 MPa,and greater than that of the other three specifications of hydraulic pipeline.The position with the maximum equivalent stress of the pipeline was at the crimping joint.
万方数据
维普
