Counter BGF Kobold Variable Area Flowmeter

Inside the flow tube, there is a star guided float which works towards a spring. An annular gap is produced between the cone-shaped magnet system and the meter ring in case of flows other than zero. The position of the magnet system depends on the resulting force of all forces acting upon it.

These forces comprise the flow force, a spring force acting opposite to the flow force, and the buoyancy and weight force significant for the measurements in case of vertical installation. Each position of the magnet holder corresponds to a flow value measured during calibration, which is transferred to a scale.

The BGF flowmeter consists of a meter tube with connections, a meter ring, and a conical magnet holder. By means of a magnet, the position of the magnet system is transferred to an encapsulated follow magnet, which has been fitted to a pointer axle. The position of a second annular follow magnet fitted on the pointer axle is transferred to the scale by means of the pointer.

Measuring / switching range:
10 - 100 ... 4000 - 40 000 l/h water
0.3 - 3.0 ...110 -1100 Nm³/h air
Connection: flange DN15 ... DN100, ANSI ¾ ... 4"
Material: stainless steel 1.4404, option PTFE-lining
pmax: PN40 (16) bar, on request max. PN600 bar
Temperature range: -40 ... +200°C (-40 ... +350°C on request)
Accuracy: ±2 % of full scale
Options: contacts, analogue output, totalizer, Hart®, Profibus® PA, ATEX




The BGF meter is suitable for flow measurement of liquid or gaseous products in pipes. The special advantage is that it can be used for all directions of flow. It shows the current flow rate in volume or mass per unit in time.

Areas of Application

Flow measurement, monitoring, adjusting and control of liquid and gaseous products. The meter’s design makes it ideal for processes under difficult and adverse operating conditions. The devices are available with additional electrical equipment for process monitoring and control.

  • A large spectrum of wetted materials
  • Magneto-resistive signal transmission
  • Special design for high-pressure and high-temperature applications
  • Excellent heat tracing technology (as option)
  • Double eddy current damping (as option)


Technical Details


  • Wetted parts:
    Measuring tube st. st.: 1.4404 (316 L)/1.4571 (316 Ti), spring st. st. 1.4571
    Measuring tube PTFE: PTFE, spring Hastelloy® C-22, special materials on request
  • Process connection: flanges acc. to EN 1092-1 ASME B16.5, DIN 2512, JIS, NPT, screw pipe, connection, special connections on request
  • Nominal pressure: PN 40, ASME Cl150 / 300 (standard) (BGF-S) PN 16, ASME Cl150 (standard) (BGF-P) higher pressure rates on request (max. 400 bar)
  • Process temperature:
    -40°C...+150°C (BGF-S with electrical output)
    -40°C...+200°C (BGF-S without electrical output)
    -40°C...+200°C (BGF-S with option V / H / W)
    -40°C...+125°C (BGF-P)
  • Ambient temperature: -40°C...+80°C


  • Liquid/gas: ± 2% of full scale
  • Additional inaccuracy by transmitter (ES): ± 0.2%
  • Repeatability: ± 0.8% of full scale
  • Protection:
    IP65 (Aluminium housing)
    IP67 (Stainless steel housing)

Certificate and accreditation

  • Explosion protection: BVS 03 ATEX H/B 112


  • Material: aluminium (stove-enameled)
    stainless steel (optional)
  • Electr. outputs: inductive switch (standard)
    inductive switch (safety design)
    others on request
  • Ambient temperature:
    (without switch)
    (with switch)

Download Datasheet: Counter BGF Kobold Variable Area Flowmeter

Reference :

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