Semi-hermetic Single-stage Screw Compressor

SRS semi-hermetic single-stage Screw Compressors include 5 series totaling 14 models with a displacement of 84 – 500 m3/h @ 2960 rpm. A large application window caters for a wide range of applications. Whereas all major refrigerants can be used, our compressors are optimized for the natural and environment-friendly refrigerants such as Ammonia R717.

The semi-hermetic construction results in a permanent technical leak-proof solution without a shaft seal.

The use of frequency inverters, a permanent magnet synchronous motor and adjustable Vi ensure high efficient operation at varying load and temperature profiles, thus guaranteeing high SEER values.

Applications where this product is suitable












Features of SRM open-type single-stage screw compressor:

  • “I”type patented profile, best lobe ratio of 5+7, high efficiency.
  • The aluminium windings of the PM motor are compatible with ammonia and need no extra protection which can get damaged or deteriorate over time.
  • Rotor is made of high- quality forged steel with micron- machining accuracy, high strength, high wear resistance, and long durability.
  • The housing is made of high- strength ductile iron, design pressure: 2.8 Mpa.
  • High- precision and wear- resistant roller bearings designed for a life span of 80.000 operating hours.
  • The internal compression ratio Vi can be adjusted to the existing operating conditions either manually or automatically for highest efficiency, even under varying conditions.
  • Integrated oil channels for secure lubrication of all critical spots within the compressor.
  • Suction and discharge ports can be swapped from left to right and turned 360° for easy mounting and connection in multiple compressor systems.

Process cooling by SRS Duopack

Farny Brewery in Bavaria, famous for their wheat-beer since more than 175 years, was conducting an extension to their refrigeration plants. F-Gas Regulation and the drive to reduce the CO2-Footprint were the motivation to replace R404A by Ammonia.

In using a semi-hermetic compressor system from SRM with its inverter drives the package is following the load profile perfectly to match the demand of refrigeration capacity. Featuring no shaft-seal is allowing to even shut down the system for longer periods (usage as backup system) without the risk of drying up the shaft seal and leakages of Ammonia.
The use of two compressors provides a very low part load capability in combination with redundancy and production security.
Due to its compactness and small foot-print the package required only small space. Assembled in Germany and customized for the application it is a perfect solution for low on-site cost of installation. Ammonia as natural refrigerant assures to be future-proof at highest efficiency.

Technical data:
Cooling capacity Qo: 2 x 160 kW
Evaporation To: -6° C
Condensing Tc: +45° C
Commissioning: 01 /2018