Flowmeters for gases, liquids or bulk solids

The measuring instruments from OCTOGON are perfectly suited for consumption and flow measurements of various flowing media. If you are not sure which flow meter is the right one for your application, simply contact us in advance and we will advise you on which system is best suited for you. One thing is certain in any case: You will always receive the latest measurement technology from us, which can be adapted to a wide range of applications - for example in plant and mechanical engineering, in industry and in quality assurance.

Modular and compact flow sensors

We offer a wide range of devices in the field of flow measurement technology. This makes it very easy to measure, monitor and display various flow values, as our measuring devices can be used for a wide variety of applications. Our measuring instruments are suitable for gaseous and liquid media as well as for solids such as bulk materials.

Modular calorimetric flow sensor for gases

Modular calorimetric flow sensor for gasesFor use in air-conditioning and ventilating plants, heating installations and the whole range of industrial facilities. With its two configurable limit value contacts, the integrated display and its numerous electrical connections, the flow sensor is also suitable for applications with higher requirements.

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Calorimetric flow sensor for gases

Calorimetric flow sensor for gasesFor use in air-conditioning and ventilating plants, heating installations and the whole range of industrial facilities. With its numerous electrical connections, the flow sensor is also suitable for applications with higher requirements.

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MODULAR AND COMPACT FLOW SENSORSFor usage in applications requiring flow as trend display. E. g. heating installations, ventilating and air-conditioning plants, fire-suppression systems or machine units. The sensor is very resilient, due to its compact design, compact dimensions and the material used.

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Flow controller

Flow controllerHeating, ventilation and air conditioning systems, fire extinguishing systems, aggregates, extractor hoods, filter monitoring, process control, fuel cells and gas measuring stations are further application examples of our flow sensors.

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DIFFERENTIAL PRESSURE TRANSMITTER VD85The differential pressure transmitter VD85 is a universal differential pressure transmitter for measurement of liquids, gases and vapours. Typical application areas are level measurement in pressurized vessels.

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RADIOMETRIC SENSOR VEGA WT31The radiometric sensor for mass flow determination VEGA WT31 is a radiation-based sensor for precise flow measurement of bulk solids.

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RADIOMETRIC SENSOR VEGA MT31The radiometric sensor for density measurement VEGA MT31 is a radiation-based sensor for non-contact density measurement of liquids and bulk solids.

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The right flow measurement for every application

Alongside temperature and pressure measurement, flow measurement is one of the most important tasks of industrial measurement technology. In practice, the choice of measurement method for the physical quantity of flow depends on the respective application. Find out here about the individual methods for flow measurement and make it easier for you to choose the right flow sensor!

Octogon offers an extensive portfolio of flow meters and sensors for industrial applications. Whether liquids, gases or vapours - we have the right solution for your process.

How is the measured variable flow rate defined?

Flow is the quantity per unit of time that flows through a pipe system. A distinction is made between volumetric flow and mass flow.

Volumetric flow - The volume that flows through a pipe per unit of time. This is the most commonly measured flow rate.

Mass flow rate - The mass that flows through a system per unit of time. In the case of variable densities, the density must also be measured.

In which applications is the flow rate measured particularly frequently?

Flow measurements are carried out in many applications, particularly in the following areas:

  • Water and wastewater
  • Chemicals and petrochemicals
  • Oil and gas
  • Energy and steam generation
  • Pharmaceuticals
  • Paper and pulp
  • Food and beverages

Typical applications include the detection of gases and vapours, aggressive or viscous liquids and the determination of flow rates in industrial processes. Flow meters are installed where the instantaneous flow in the pipe network needs to be recorded or in industrial measurement technology and process automation where the flow needs to be monitored and further processed.

What flow measurement methods are available?

Our flowmeters are based on proven measuring principles such as:

  • Calorimetric flow measurement: The method works with 2 resistance sensors, one of which serves as a heating element and the other as a measuring element for the medium temperature. The temperature difference between the heating medium and the medium is kept constant and the required heating power is measured. The higher the flow rate of the medium, the more heating power is required to keep the temperature difference constant. The heating power can therefore be used to draw conclusions about the respective flow rate. The power fed in is a measure of the flow rate. Advantages - Calorimetric flow measurement offers a high degree of accuracy and sensitivity, especially for low flow rates. For use in air, liquids and granulates. Leakage measurement is also possible.
  • Flow measurement with differential pressure/active pressure sensors: Differential pressure sensors include orifice plates, pitot tubes or Venturi tubes. Differential pressure sensors measure the difference between two absolute pressures in gases, vapours and liquids. Areas of application include monitoring filters, measuring fill levels in closed containers and in safety-critical systems or flow measurements in combination with differential pressure transducers. They are also referred to as differential pressure transmitters or differential pressure transducers. A differential pressure transducer consists of two hermetically sealed chambers, each with a process connection, which are separated from each other by a flexible diaphragm to which a resistance bridge is bonded. To ensure that the pressures act on the diaphragm in opposite directions, the process connections are connected upstream and downstream of a possible pressure drop. The diaphragm remains flat if the pressure in the chambers is the same. If the pressure in one of the chambers falls or rises, the diaphragm tilts in the direction of the chamber with the lower pressure. The difference between the two pressures corresponds to the degree of deformation. The measurement is made via a change in resistance, which can be converted into an electrical signal. Advantages - High temperatures and pressures can be realised thanks to the mechanical flexibility of the differential pressure sensor, for gases, liquids and steam.
  • Radiometric sensor for non-contact density measurement of liquids and bulk solids. A radioactive source, usually caesium-137 or cobalt-60, emits gamma radiation into the pipe or container containing the medium to be measured. A radiation detector is located on the opposite side, which measures the intensity of the penetrating radiation. Depending on the density of the medium, the radiation is attenuated to a greater or lesser extent. The density of the medium can be calculated from this attenuation.
    Radiometric density measurement is particularly suitable for applications under extreme conditions such as high temperature, pressure or aggressive media, as it is non-contact and wear-free. It offers high reliability and accuracy and only requires a single calibration.

The selection of the appropriate measuring method depends on the medium to be measured, the operating conditions (pressure, temperature) and other factors such as accuracy, costs and installation conditions. Expert advice is therefore important when selecting the right gas measuring device.

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