Signal detection via the pole wheelSignal detection via the pole wheelWith this method, the impulse transmitter detects the impulses via a pole wheel, which is attached to the measurement screw. Based on specifications and need, pole wheels with differing numbers of poles can be used. This enables a significantly higher signal transfer resolution. Signal detection via the pole wheel is used when a high signal resolution is needed, e.g., with test and calibration benches or with the use of a flowmeter in the lower flow range.

KRAL Flowmeters OMG Series.

Universal device for manifold application needs.

Due to their continuous ongoing development, the highly modular OMG series covers a broad range of applications. This series is therefore particularly suitable for manifold applications, such as mechanical engineering, chemical engineering and marine.

The flow meters OMG series also combines robustness with highest precision, characteristics for which KRAL flow meters are well-known worldwide. Due to the screw pump principle, all OMG series devices are very smooth-running and fast, and can follow quick, pulsation-related changes in flow rates. Due to their extremely robust construction, the OMG series provides optimal protection against external influences, such as system vibrations and mechanical stresses in harsh environments.

Your benefits.

  • Wide range of applications which have a manifold need for flow measurement, such as mechanical engineering, chemical engineering and marine.
  • High precision flow meter.
  • Extremely robust.
  • Stabilization zones unnecessary.
  • Easy installation.
  • Very smooth-running, follows any rapid fluctuations in the flow causes by pulsations
  • Low friction and minimal loss of pressure.

Technical data.

  • Media: Chemically neutral, lubricating, clean, non-abrasive.
  • Flow direction control: Extended sensor range optional.
  • Temperature measurement: Additional sensor optional.
  • Sensor: PNP, Namur or Push-pull.
  • Process fittings: DIN, ANSI, thread. Further connections upon request.


  • Housing: Spheroidal graphite iron.
  • Screws: Nitrided steel.
  • Bearings: Steel or hybrid bearings.
  • Sealing: FKM. Other seal materials upon request.
  • Technical data.
    Technical dataOMG-13OMG-20OMG-32OMG-52OMG-68OMG-100OMG-140
    Nominal diameterDN [mm]152025/324050100150
     DN [inch]1/23/411 1/2246
    Total length with DIN flange[mm]145185255/265285340460610
    Weight with DIN flange[Kg]6613/15213177190
    Flow rate I/hQmax9002,7009,00031,50063,000180,000450,000
    Flow rate I/minQmax15451505251,0503,0007,500
    Max. pressure[bar]2502502501601004040
    Temperature[°C]-20 to +200-20 to +200-20 to +200-20 to +200-20 to +200-20 to +200 -20 to +200
    Viscosity[mm²/s]1 to 1x1061 to 1x1061 to 1x1061 to 1x1061 to 1x1061 to 1x106 1 to 1x106
    Precisionmeasurement of value±0.1 %±0.1 %±0.1 %±0.1 %±0.1 %±0.1 % ±0.1 %
    Repeatability ±0.01 %±0.01 %±0.01 %±0.01 %±0.01 %±0.01 %±0.01 %
    K-factorK1 [P/I]1,21664023471.039.816.88.8
     K2 [P/I]2,4321,28046814279.633.617.7
     K3 [P/I]7,2962,5601,01430216757.622.1
     K4 [P/I]7,2962,5601,01430216787.645.1
    Frequencyf1 at Qnom [Hz]203320390414464560738
     f2 at Qnom [Hz]4056407808289291,1201,475
     f3 at Qnom [Hz]1,2161,2801,6901,7601,9491,9201,842
     f4 at Qnom [Hz]1,2161,2801,6901,7621,9482,9203,758
  • Sensor.
    SensorBEG 06* / BEG 06A*BEG 43DBEG 44ABEG 45 with BEV 13BEG 47D** / BEG 47E**BEG 53A* / BEG 54A*
    Application Ex-rangeStandardHigh pressureHigh pressure, wide temperature rangeEx-rangeFlow direction detection
    K-factor K1K1K2K3K1K4
    Signal NamurPNPPNPPNPNamurPush-Pull
    Temperature[°C]-40 bis +150-40 to +150-40 to +200-40 to +250-25 (-40) to +150-40 to +150
    Max. pressure[bar]35025042042040650
    *dependent on nominal diameter**dependent on temperature
  • Operating instructions.