NK31 Air Compact Unit

NK31 Screw Air Compact Unit
NK31 Screw Air Compact Unit

Power range up to 7.5 kW / 10 HP

Capacity up to 1.2 m³/min / 43 cfm

Pressure up to 15 barg / 220 psig

Weight approx. 39 kg / 86 lbs

Our NK compact units provide optimum operation reliability and reduced design costs for your compressor package.

WHY TO USE NK COMPACT UNITS

  • High operation reliability – designed for industrial applications and continuous operation
  • Includes all advantages of our built-in EVO® technology, ensuring our OEM partners benefit from:
  • No leakages due to reduced piping and connections as well as sealing with O-rings (Viton®)
  • Optimized compact design with very low space requirements
  • Simplified service and maintenance as all components are easily accessible from one side without special tools
  • Reduced engineering, manufacturing and logistics costs for your compressor package compared to conventional compressor systems with an air end and separate components
  • Each compact unit is tested as a complete system before leaving our factory

The following components are integrated into each compact unit: EVO® oil-injected air end with ROLLING PROFILE®, intake valve with control unit and air filter, oil reservoir and oil separation system with coalescing cartridge(s), oil filter and oil thermostat valve, minimum pressure valve and non return valve.

Various options are also available, such as safety valve, oil level sight glass and maintenance indicators.

All information at a glance!

Advantages of our new EVO® technology

  • New ROLLING PROFILE® – ultimate efficiency with reduced noise
  • Long life cycle due to increased bearing dimensions and wear-free ROLLING PROFILE®
  • Wide operating pressure range from 5 to 15 barg
  • High manufacturer assembling – "Made in Germany"
  • Quality assurance – bench test of every air end before leaving our factory
  • Easy application selection with our new ROTORCOMP® SIZING AIR Software
  • Highest flexibility for your package design
    • Suitable for all types of motors
    • Drive options: Belt drive, direct drive, internal gear drive
    • Base and face-flange mounting

Ultimate efficiency and reduced noise through

  • High volumetric output due to
    • Reduced internal leakage
    • Thermally optimized oil injection system
    • Improved suction port efficiency giving reduced internal losses
  • Low power consumption due to
    • Optimized torque characteristics and reduced internal friction
    • Improved outlet port with lower pressure losses
  • Reduced noise and low vibration due to
    • Smooth rolling of the rotors with new ROLLING PROFILE®
    • Optimized outlet port

For detailed design, please order the installation drawing/3D model.

Technical modifications and errors excepted!

EVO®-NK Range

Type Recommended motor
power min. – max.
Max. flow rate
at 7 barg / 100 psig
Pressure range
min. – max.
Net weight approx.
  kW hp m³/min cfm barg psig kg lbs
EVO1-NK 2.2 – 5.5 3 – 7.5 0.8 30 5 – 15 70 – 220 31 68
EVO2-NK 4.0 – 11 5 – 15 1.6 60 5 – 15 70 – 220 40 88
NK31 3 – 7.5 5 – 10 1.2 43 5 – 15 70 – 220 39 86
EVO3-NK 7.5 – 18.5 10 – 25 2.8 100 5 – 15 70 – 220 54 119
EVO6-NK 15 – 37 20 – 50 5.5 200 5 – 15 70 – 220 99 218
EVO9-NK 22 – 55 30 – 75 8.4 300 5 – 15 70 – 220 199 439
NK200 45 – 75 60 – 100 11.5 408 5 - 15 70 - 220 263 580


* reduced maximum power and maximum rotation speed input at pressure below 7 barg