SI series: maximum energy efficiency – even in partial load operation

Compressed air is indispensable for many industrial processes. However, it is also a very cost-intensive medium – and therefore offers an important lever for energy savings. As one of the world’s leading manufacturers of machines for conveying and compressing air and special gases, AERZEN knows exactly what the requirements are and develops innovative high-end solutions for the key challenges facing the industry. The new oil-injected air compressors in the SI series strike an optimum balance between performance, efficiency and economy, thus ensuring a significant reduction in energy consumption and operating costs.

Highest energy efficiency

The SI screw compressors have an integrated permanent magnet motor (PM motor) and an innovative, robust screw compressor stage with new, highly efficient 4+6 profiles. The PM motor scores highly in terms of efficiency, even at low speeds, and thus also achieves an excellent energy efficiency of approx. 96% in partial load operation. The rotor is connected directly to the compressor shaft so that additional losses in the drive train are avoided. The required quantity of compressed air is adjusted as needed using a VFD. The ideally harmonised combination of a high-quality drive train and a highly efficient compressor stage results in particularly efficient operation of the entire package.

Unrivalled reliability thanks to robust design in a compact package

The new series is extremely robust, unrivalled in reliability and very compact in design. It is available in ten different sizes from 7.5 to 75 kW and is used in numerous, sometimes demanding applications with differential pressures from 5.5 to 13 bar and volume flows from 20 to 756 m³/h. Pressure and operating temperatures are constantly monitored. This ensures stable and safe production processes. Thanks to the acoustically optimised acoustic hood, the double-walled oil cooling jacket for the PM motor and compressor stage, and the use of a centrifugal fan, minimum sound pressure levels of 70 dB(A) are also achieved. Special accessories also enable the operation of these compressors in particularly high or low ambient temperatures, for example in polar regions or desert areas. In extreme climatic conditions, the oil cooler included in the standard scope of supply sustainably increases the reliability of the package.

High level of service-friendliness for reduced service costs

The PM motor technology works entirely without roller bearings. This eliminates the need for lubrication and the usual bearing replacement. The anti-friction bearings of the compressor stages are designed for a service life of at least 30,000 hours, further reducing maintenance and service costs. Cooling and lubrication are provided by a common oil circuit in both the compressor and the PM motor. The compact type of construction results in a small machine footprint and allows a space-saving side-by-side installation. All components are accessible from both the operating and the rear sides. This ensures ease of operation and simple maintenance.

By the way: investments in energy efficient compressed air technology such as the new AERZEN SI compressors are supported by the state via the BAFA subsidy programmes. Please feel free to contact us!

You will find AERZEN at the Hanover Trade Fair 2025 in Hall 12 at stand D40 (main stand) and in Hall 013 at stand B24 (focus: hydrogen compression).