Abstract: Centrifugal compressors have the characteristics of high revolving speed, large pumping flow, well compacted structure, small self-weight as well as small footprint. The popular foundation types for these structures are large block or frame structures. With the rapid developments in China's oil refining industry, the high speed compressors are widely used in the refineries. The foundation for the centrifugal compressor structure design is to control the vibration within the permissible limit so that the foundation vibration will affect the machine's normal operation. The excessive vibration induced form the dynamic foundations will adversely affect production, cause differential settlement at the adjacent structures and foundations. This paper presents a case history of vibration testing results on the dynamic foundations for a refinery in Yunnan. Testing was performed on different soils and foundations, the natural frequencies of soils and foundations are compared with the machine's operational frequencies.

Key words: Centrifugal Equipment； Foundation Stiffness Coefficient, Damping Ratio Properties Evaluation, Vibration Mass