The ammonia production of Odessa port plant uses two single-type units with centrifugal flow compressors. In total, there are twenty eight turbine casings and compressors, and twenty six of them are characterized by levels of permissible vibration. However, the staff has been concerned about low-pressure casings (LPCs) of two compressors 103 J since 2004, as they repeatedly have low-frequency vibration. The characteristic of the vibration state of two casings LPC-1 and LPC-2 for an extended period of operation is given in the paper. It is shown that parameters of the structural and functional state influence the appearance of excessive vibration in compressors, including those of a resonant behavior. Measures undertaken by the specialists of the plant to eliminate and prevent these phenomena are described in the paper.