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DFR-01 two-phase flow meter

DFR-01 two-phase flow meter

The DFR-01 two-phase flowmeter is designed for technological measurement of the flow and quantity of gas and liquid in gas condensate wells. Measurement is performed by means of the variable differential pressure method.
This flowmeter is designed for installation on a pipeline with a nominal diameter of DN100. The mixture mass flow measurement range is 2 to 20 t/h. The working pressure is 16 and 25 MPa. [This says that there are only two possible working pressures] The upper limit of the pressure difference measurement is up to 25 kPa.
The DFR-01 two-phase flowmeter is designed to measure, record and convert into output signals:
  • liquid quantity in mass units;
  • gas quantity in mass and volume units;
  • liquid mass flow;
  • gas volume and mass flow.

Intended use

The DFR-01 flowmeter is designed for use in industrial facilities as an independent measuring tool, as well as in automated metering and control system or for information transfer to other systems.

This flowmeter is designed for use in explosion hazardous areas in accordance with the types of explosion protection of individual components. Explosion protection marking for the key parts of the flowmeter are 1ExibIIBT5 X and 2ExmIIT5.

Signature features:

Measurement of the flow rate of the gas and liquid phases according to the specified total component composition
Operation at temperatures as low as -60 °C
Continious operation time of at least 45,000 hours
Data transmission in digital form (HART or MODBUS RTU protocol)
The flowmeter can be integrated into any telemetry and telemechanical system
Increased resistance to cold
Continuous operation time: at least 45,000 hours
The DFR-01 can operate continuously for at least 45,000 hours when powered by the built-in power supply unit.
Data transmission in digital form
Data transmission in digital form (HART or MODBUS RTU protocol)
The DFR-01 can be integrated into any telemetry and telemechanical system


Measurement pipeline internal diameter, mm
90 to 100
Measured media
gas-condensate mixture
Liquid-gas mixture flow measurement limit, m3/h
Mixture mass flow measurement range, t/h
2 to 20
Proportion limit of the gas phase mass (Qmg) to the liquid phase mass (Qml) of the liquid-gas mixture under operating conditions
Qmg/Qml > 3
Limit of the content of the liquid phase per one cubic meter of gas reduced to normal conditions for the gas-liquid mixture, max, g/nm3
Excess pressure measurement upper limits, MPa
16; 25
Upper limit of differential pressure measurement, kPa
Up to 25
Temperature measurement limits, °C when using:
copper RTTs with W100=1.4280
-40 to +100°C
platinum RTTs with W100=1.3910
-40 to +100°C
NSU rod position, mm
20 to 30
Temperature measurement limits when using the platinum technical resistive temperature transducer TPT-1, °C
-60 to +60
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Measuring principle:

The basis of operation of this flowmeter is measurement using the principle of differential pressure. When a two-phase medium passes through a constriction device, the phase with the higher density, i.e. the heavier one, accelerates through the constriction more slowly than the lighter phase due to inertial forces. The strength of deceleration of the heavier phase, compared with that of the lighter phase, will be correspondingly greater in accord with the difference in the phase densities.

This process is accompanied by an increase in the concentration of the heavier phase. With further expansion of the flow, the speed of each phase, constantly decreasing, returns to the original value. At the same time, the concentration of the heavier phase also returns its the initial value.

The shorter the axial length of that part of the constriction device through which the flow accelerates, the lesser the portion of the potential energy (or the pressure difference) is expended on the acceleration of the heavier phase. An orifice-type constriction has the shortest axial length. Therefore, for gas-liquid mixtures with a large difference in density between the heavier and lighter phases and a small volume concentration of the heavier phase, the pressure difference in the orifice is almost entirely expended on the acceleration of the lighter phase and practically has not impact on the heavier phase. Consequently, the orifice, essentially, measures the flow rate of the lighter phase. To measure the heavier phase, a non-standard constriction device (NSU) is used. This has a long axial length through which the media flow is constricted.


show package contents
Main set
Accessory kit;
Portable terminal PT-003;
Spark protection barrier BIZ-002;
Temperature stabilization unit BTS-003 with the KP 6-12 HL1 connection box;
TPT-1-4 100P resistive temperature transducer;
Protective cover;
Sensor adjustment kit: (connection cable + CD-R with software);
Verification kit: (cable (for connection of a resistive temperature transducer) and a cable (for connection of the device to the TC and the frequency meter during verification));
* may be altered. Clarified at the time of order
show package contents


Grade 1 gas volume flow rate standard in value range of 30...20000 m³/h