ISO 12500 — Compressed Air Filter Tester

Compressed Air Filter test rig

DescriptionCompressed Air Test Rig

The CAF test rig allows testing of high efficiency compressed air filters using aerosol size distribution measurements taken both upstream and downstream of a filter. This allows assessment of both the filter's efficiency, by particle size and offers a computed value for the inlet and outlet mass concentrations, as required in the test report section of BS ISO 12500-1:2007 Filters for compressed air - Test methods - Part 1: Oil Aerosols.

The standard requires generation of a poly-dispersed oil-aerosol distribution, having an average size by particle diameter in the range 0.15µm to 0.4µm and a concentration of 10 mg/m3 for high efficiency / point of use filters and 40 mg/m3 prefilters.

The downstream measurement is specified as being performed, either in accordance with the gravametric method given in ISO 8573-2, or using a white light scattering aerosol photometer. Specifically the instrument must be capable of sampling the air at test pressure.

The white light scattering welas® digital sensor is one of the very few instruments that can meet these specifications allowing direct measurement at line pressure and giving an assessment of efficiency against particle size together with a calculated mass concentration, based on density of the oil used. The ability to select each of the welas sensors in the system also allows use of a high challenge concentration on the upstream side and a high sensitivity sensor on the downstream side of the filter on test.

The AGF 2.0D allows the generation in the particle sizes required at upto 60 mg/min (with DEHS) at pressures upto 10 bar and is compatible with ISO 3448 (Viscosity grade 46) lubricants.

Where higher output is required, multiple generators can be utilised operating in parallel with each other.

Custom builds are also possible.

Technical parameters

  • Measuring range: 0.2 µm – 40 µm
    • < 1 up to 1000000 Particles/cm3
  • Volume flow:
    • Sampling: 5 l/min
  • Power supply: 115/230 V ; 50/60 Hz
  • Compressed air supply: max. 8 bar

Particular advantages

  • Fully pressurisable components, generator and spectrometer.
  • Measurement of the particle size distribution and particle concentration in up / downstream
  • User selectable welas® digital sensors
  • Scaleable solution to cover a large range of filter sizes and flows
  • Low maintenance
  • Easy handling
  • Reliable function

Please contact us for more detailed information.