Analysis and Treatment of Pipeline Vibration in Centrifugal Compressors

Abstract While going through the startup process of a centrifugal compressor unit, the pipline of compressor tertiary outlet bypass to a gas expander and supporting structure was observed to be shaking abnormally. The shaking was significant enough that worker feld foot numbness on the steel grating and at a level that the owner was afraid of approaching the piping. The initial assumption was that the piping or the piping supports had been improperly designed. After being reinforced with the supports, the vibration still hadn’t been alleviated. Further investigation revealed that the root cause of the problem was a flow-generated pulsation of the compressor that excited the pipeline shell mode. But the project’s start-up schedule was tight, and had no time to use CFD to analysis the reason. meantime it’s hard to change the excitation of the compressor and the mode of piping. The ultimate solution to the problem was the “flow-splitters” method to reduce the pulsation. we installed two porous noise reduction plates on the original flange of the pipeline. At last the vibration dropped to an acceptable range in the shortest possible time, ensuring the start-up progress. It provided a practical basis for the treatment of pipeline vibration of large centrifugal compressor in the future.