Study On Dynamic Characteristics Of Pipes For Reciprocating Machinery Based On ODS

Reciprocating machinery is important mechanical equipment in petroleum,chemicals,and other process equipment.The vibration of the pipeline connected to it is a common problem in pipeline design,installation,and pipeline transportation.Excessive pipeline vibration can cause structural damage,and reduce the service life of the equipment,and even cause large-scale accidents,causing heavy casualties and economic losses.Therefore,determining the cause of pipeline vibration and the location of damage is the key to ensuring the safe and stable operation of reciprocating machinery and pipelines and preventing such accidents,and pipeline dynamic characteristics analysis is one of the effective solutions.For this reason,this article takes the pipeline as the research object,combines the simulation analysis with the experimental verification,and carries out the research on the pipeline dynamic characteristics analysis method.For this reason,this article takes the pipeline as the research object,combines the simulation analysis with the experimental verification,and carries out the research on the pipeline dynamic characteristics analysis method.Through the analyses of the vibration mechanism of the reciprocating mechanical pipeline,it provides a theoretical basis for the subsequent simulation analysis and pipeline experiment to impose different signal-to-noise ratio periodic excitation;Secondly,according to GB/T 22315-2008,we take a straight pipe as the research object,use The hammering EMA to test and analyze the modal frequency of the suspended pipeline,determine the actual elastic modulus of the material combined with the ABAQUS finite element modal analysis results,and establish an accurate finite element model of the pipe section.On the basis of the straight pipe,we can take a cantilever pipe with one end fixed to the support and one end free as the research object to modify the finite element model according to the modal parameters obtained by hammering EMA,and the harmonic response analysis under different signal-to-noise ratio periodic excitation is carried out;Meanwhile,according to the results of acceleration response analysis,combined with ME’Scope software,we study the selection of reference points and the identification of dynamic characteristics based on ODS FRF and OMA.The results show that,compared with OMA,ODS FRF can still identify the excitation frequency and modal frequency under periodic excitation with low SNR.Finally,we use a complex pipeline consisting of straight pipe,elbow pipe,π-shaped pipe,branch pipe,guide bracket and fixed brackets as the research object to verify,establish the simulation model of pipeline support damage location that is based on ODS FRF by setting two damage conditions of guide support and fixed support stiffness weakening respectively,verify the effectiveness of the model in identifying the location of the support damage,thereby providing a theoretical basis for the actual pipeline damage detection of reciprocating machinery.