Pumps, compressors and blowers, machines; industrial blowers; power-operated blowers; air blowers; air compressors; turbo blowers; centrifugal blowers; blowers and compressors for aeration and oxidation; power-operated blower systems for industrial applications, wastewater applications, fermentation, water and effluent treatment, gas desulphurization, and air supply; centrifugal compressors