Mitsubishi Electric: Oil-free Compressors

Oil-free magnetic bearing compressors have a two-stage impeller system, and they are designed to handle a broad operating range, both in high lift (air-cooled chillers in hotter climates and heat recovery) and low lift (process cooling applications). Oil-free compressors are powered by an incredibly high-speed permanent magnetic motor. Compression is created as the first stage impeller draws the refrigerant gas in, the flow is regulated by the variable inlet guide vane which maximizes the compressor range in both surge and choke conditions as the impeller moves and energizes the gas, it begins to flow through the piping and onto the second stage impeller where process is repeated, and the refrigerant is discharged from the compressor. Oil-free compressors are optimized to work with various refrigerant gases such as R-134a; R513A and the low GWP R-1234ze.