Multiphase Metering: Flowatch


Multiphase flow metering Flowatch

The Pietro Fiorentini FLOWATCH is non-intrusive, non radioactive in-line tool for multiphase metering. It is used for measuring flow rates of oil, water and gas from a well stream or in a pipeline.

Among the applications of the FLOWATCH are:

  • Individual well monitoring offshore and onshore
  • Offshore well testing
  • Onshore well testing
  • Allocation metering
  • Mobile well testing

Based on well-established measurement principles, such as Venturi, capacitance/conductance, cross-correlation. The major parts of the multiphase metering FLOWATCH meter are the Venturi insert and the electrodes incorporated inside the throat of the Venturi insert. The flow rates of oil, water and gas are calculated based on the measurements obtained by the electrodes and the measurement of the differential pressure across the Venturi inlet. No separating devices, mixers, by-pass lines or radioactive sources are used. The velocity is found from cross-correlating the high resolution time signals from pairs of electrodes within the Venturi insert. The density is determined indirectly, through the well known momentum equation ("Venturi equation").

The key feature of FLOWATCH are:

  • Non radioactive: environmentally friendly and safe to operate.
  • Compact Design: reduced space and weight, small footprint and no requirements for upstream and downstream straight pipe length.
  • Easy to install and operate: vertically installed, no special requirement for upstream pipe geometry, calibrated at the factory. Calibration at site not required. Low pressure losses.
  • Low maintenance: standard maintenance required for differential pressure, pressure and temperature transmitters.
  • Field tested: field tested and installed by major oil and service companies world wide
  • High reliability: robust and reliable components.
  • High rangeability: covers wide operating range, all flow regime. Low sensitivity to variation in oil properties, not influenced by presence of H2S or CO2.
  • High flexibility: used for onshore and offshore applications such as individual well monitoring, well testing, allocation metering, mobile well testing.

The key components are:

  • Multiphase Metering Section including DPT, PT and TT transmitters
  • Sensor Electronics (Mounted in field enclosure on Metering Section)
  • Flow Computer
  • Human Machine Interface