Simulation And Experiment Analysis Of The Gas Pipeline Free Span Detection Under The Inner Pipe Active Excitation

Pipeline is the most economical and effective way to transport gas and liquid materials over long distances.It is widely used in cross-regional transportation of oil and natural gas resources.In order to avoid damage to the pipeline,it is usually buried underground.However,due to the movement of the earth's crust,natural erosion,and manual operations,the pipeline may become vacant.This method will cause huge safety risks to the pipeline.At present,the method of external detection is mostly used for pipeline free span detection.This method is easily affected by the complex environment outside the pipeline,and it has the characteristics of low efficiency and high cost.In this paper,an in-pipe detection method is proposed for the detection of free span.According to the difference in the vibration response,it extrapolates the support of the pipe to effectively avoid the disadvantages of the external detection.In this paper,the coupled characteristics of the pipe and soil are analyzed based on the beam theory of elastic foundations.Simulations are performed according to the free span conditions that may occur in different laying environments.The ADAMS software is used for frequency response function analysis and modal analysis,and then the pipelines are analyzed.In the state of dynamic response,a qualitative judgment is made as to whether there is an pipeline free spam,and the effect of the length of the pipeline free span and the hardness of the supporting medium on the frequency response function is summed up,and the identification characteristics of the free span are obtained and experimentally verified.