Experimental Investigation of the Effect of Coupling Misalignment of a Centrifugal Pump Unit on Its Vibration and Noise Characteristics

The article presents the results of a study of the effect of the coupling misalignment of the centrifugal pump unit on its sound power and vibration velocity of the rolling bearings. This research is a part of the major research devoted to studying the factors affecting the noise and vibration characteristics of pumps and compressors, which is conducted by Chelyabinsk Compressor Plant LLC in collaboration with the Department of Hydraulics and Hydraulic and Pneumatic Systems of South Ural State University. The relevance of the research is determined by the lack of clear standardized guidelines for ensuring the quality of alignment, and in some cases their obsolescence and the inability to meet the national standards or customer requirements. In research, a specialized laser alignment system equipped with software with its recommendations for misalignment tolerances was used to ensure the reliability of the alignment of the unit coupling. Sound power was evaluated in accordance with GOST R ISO 3744 and vibration velocity was evaluated in accordance with GOST ISO 10816–3 and GOST 32106. The results show that at a constant speed and power consumption of the pump unit, there are both the lower critical tolerance, at which further reduction of misalignment to zero values is unreasonable, and the upper critical tolerance, at which unpredictable vibration and noise occur. Upon that, the angular misalignment has the most significant influence on the vibration level.