Kaeser’s DSD rotary screw compressor product range offers added versatility with the addition of four models (the DSD 142, 172, 202 and 238), which are available with an optional integrated refrigeration dryer and/or frequency control module. The rotary screw compressors are suitable for air deliveries from 13 to 24 m³/min (at 7.5 bar). Redesigned component layout and the use of new materials have enabled the depth of the units to be reduced by more than 200 mm. At the heart of each system is a DSD rotary screw compressor, which can be complemented by a thermally shielded refrigeration dryer module as required. This option not only provides both efficient compressed air production and drying, but also means that the compact package requires far less floor space than a comparable conventional system. As the use of variable speed drive has advantages for certain applications, all DSD models, including those with the refrigeration dryer module, are available with Sigma Frequency Control (SFC).