Cause On The Vibration At The Inlet Pipe Of Cycling Compressor And The Research Of Transformation

Reciprocating compressors are widely used in petrochemical and other fields due to their high efficiency.There are countless accidents caused by the vibration of the compressor piping,and its vibration amplitude is also an indicator for evaluating the performance of the compressor.According to relevant data,most of the compressor accidents in China originate from pipeline vibrations,and pipeline vibrations are very harmful.Therefore,it is very important to study the vibration problems of liquid separator tanks and compressors and optimize their structure.Firstly,the mechanism of pipeline vibration is introduced in this paper.It is pointed out that the pipeline vibration is mainly caused by the pipeline structure and the gas characteristics inside the pipeline.The plane wave theory and relevant equations are introduced.Use the three-dimensional software UG was to create a finite element model of the liquid separation tank.Then observed the vibration model of the liquid separation tank and the natural frequency of the low-order.The finite element analysis was performed on the compressor and the inlet pipe of the liquid separator tank to observe its natural frequency.It was concluded that the vibration of the liquid separation tank and pipe was due to the first order frequency of the compressor inlet pipe and the excitation frequency of the compressor falling within the resonance area,causing resonance.The harmonic response analysis of the inlet pipe of the compressor shows that the vibration amplitude of the pipe is larger under the excitation frequency.Afterwards,the theories and steps of the ANSYS acoustic simulation method for calculating the air column frequency are introduced,and the air column frequency of the straight pipe and the straight pipe with the buffer tank is simply simulated.Finally,acoustical simulation of the inlet pipe of the compressor was performed to calculate the frequency of the pipe air column.The analysis results showed that the air column was one of the reasons that affected the pipe vibration.In summary,the vibration of liquid separation tanks and pipelines is mainly due to the fact that the natural frequency and the air column frequency of the inlet pipelines of the compressor are close to the excitation frequency and generate resonances.Therefore,it is necessary to optimize and improve the pipeline structure.The control method of pipeline vibration mainly introduces the relevant theoretical standards of API618.For the resonance of the pipeline structure,change and increase the constraints on the pipeline to increase the natural frequency of the pipeline structure.For the aerodynamic characteristics in the pipeline,the current commonly used method is to add buffer tanks,orifice plates or change the pipeline structure to reduce vibration.Finally,the inlet pipe of the compressor was improved.Through the analysis,the vibration after the improvement was obviously reduced.