The new Boge Bluekat range of screw compressors feature an integrated converter which the company claims offers a more effi cient solution to providing oil-free compressed air. These compressors are based on screw type compressors with traditional oil injection but feature a converter integrated directly after the compression stage. This serves to oxidise the oil contained in the compressed air into carbon dioxide and water. Boge says the purifi ed air has a residual oil content of less than 0.01mg/m3 and is thus considered to be absolutely oil-free compressed air. This result is achieved independently of the quality of the intake air. The models in the Bluekat series are intended to cover the 30 and 37kW performance classes and produce 3.71 - 5.01m3/min oil-free compressed air at 8, 10 or 13 bar. A variant with a frequency controlled drive is also available.