2018 Kaeser SFC-30ST Variable Speed Rotary Screw Air Compressor

The Kaeser SFC 30ST is a 40 HP variable speed rotary screw air compressor built around the direct-drive Sigma Profile airend, a design Kaeser has made a staple of plants that cannot afford an air outage. Sigma Frequency Control matches output to demand through a Siemens variable frequency drive, delivering 37 to 176 CFM at 125 PSIG and 34 to 145 CFM at 175 PSIG while holding line pressure to within +/- 1.5 PSIG, so the motor draws only the power the shop is actually using. The T designation means the refrigerated air dryer is integrated into the cabinet and sized for the full flow of the compressor, and the Sigma Control 2 controller adds an onboard Ethernet port for plant monitoring and Industrial Internet of Things integration. Direct drive removes the belts and tensioners entirely, and the airend turns at lower speeds across the range, which is where the efficiency and service-life gains come from. This unit sells as a complete compressed air room rather than a bare compressor: a Samuel 400 gallon vertical receiver tank, dual Kaeser inline filtration housings plumbed in series for particulate and coalescing oil-mist removal, and a Kaeser automated condensate drain with an oil and water separator for compliant wastewater discharge. It is a clean, professionally maintained package that is ready to pipe in.

Step down one frame in the SFC family and you land on the Kaeser SFC 22ST, the 30 HP unit this machine supersedes, and the differences are structural rather than cosmetic. The SFC 22ST is a belt-driven machine; the SFC 30ST is direct drive, which eliminates belt tension checks, belt replacement intervals, and the transmission losses that belts introduce at every operating point. Flow moves up with it: the SFC 22S is published at 33 to 141 CFM at 125 PSIG, while the SFC 30ST delivers 37 to 176 CFM, a wider turndown band at both ends that lets one machine cover a low weekend load and a full production shift without cycling or a second compressor. The larger airend also holds its rated flow better at elevated pressure, giving 34 to 145 CFM at 175 PSIG for shops running high-pressure tooling or air-over-oil equipment. Add the integrated full-flow dryer, the 400 gallon receiver, and two-stage inline filtration already bundled here, and the buyer is not just getting a bigger compressor than the 22ST - they are getting an entire air system that arrives sized, matched, and ready to run.