Study On Bending Vibration Test Device And Image Monitoring Method Of Pipeline

Pipeline transportation is the first choice for many energy transportation because of its practicability and economy,but it is easy to produce leakage at the pipeline interface affected by the external environment in the course of long-term work,pipeline leakage not only causes huge losses but also pollutes the environment.Therefore,we designed a new type of bending vibration test device to test the fatigue of the pipeline,which uses a new type of multi-functional inertia vibration exciter to load the first-order vibration of the pipeline specimen,at the same time,the flexible support is selected at the joint of the pipe specimen,and the vibration exciter can adjust the frequency and force of the vibration exciter in real time.The method of quasi-real-time monitoring is used to extract and analyze the test results.The perfect solution to the harsh monitoring environment and expensive monitoring equipment is put forward,and the precision of the test results is high.In this paper,the following aspects of experimental research.1)To analyze the form and cause of the harmful vibration of the pipeline,establish the mechanical model of the pipeline specimen according to the principle of vibration mechanics,obtain the calculation formula of the pipeline vibration parameters,and seek a method of applying the first order vibration model to the external load of the pipeline to provide the theoretical basis for the experiment.2)When solving the vibration of the pipeline,the modal analysis of the pipeline is carried out by Ansysy,the relationship between the geometric parameters of the pipeline specimen and the vibration parameters is explored,the resonance frequency and the node position of the first vibration mode are calculated,the exciting power of the test is determined,and the structural design and motor selection of the new multi-function inertia exciter are completed according to the vibration parameters and power.3)Study the technical measures of adding support at the joint,establish the flexible support to replace the theoretical model of no support and the structural and mechanical performancecondition of the support.4)Taking advantage of the particularity of the spatial vibration of the pipe sample,the amplitude and stress information can be obtained by photographing any section of the pipe sample,and a quasi-real-time monitoring method using CCD camera with short time and intermitten exposure is developed.5)Drawing the principle diagram of the test apparatus,using Visual Studio to write the control program,using the upper computer to control the servo motor and the step motor through the motion control card,to complete the accurate control of the load and frequency in the exciting process,and through the preparation of the image processing program of Matlab,to monitor the amplitude,and feedback to the upper computer to adjust the exciting power accordingly,to achieve the automation of the test.6)To carry on the actual operation to the design experiment,through the analysis experiment data and the operation process question to carry on the verification and the revision to our design,realizes the entire experiment machine the integrality...