Measurement method:
The hot-wire (thermal) mass method of measurement is based on the dependence of the degree of cooling of a heated sensitive element, placed in the stream, due to flow rate. The heated sensitive element in gas flowmeters is a platinum resistance thermometer.
The instruments maintains in real time the constant difference of temperatures between the heated sensitive element of the hot-wire flowmeter and the thermal converter which measures gas temperature. The power needed for maintaining the constant temperature difference is proportional to the mass speed of the gas flow which passed through the metering section. The current value of gas flow rate is calculated according to the value of dissipated heat power of the hot-wire flowmeter, composition and thermophysical properties of gas, pressure parameters, as well as dimensions of the sensitive element of the primary transducer and pipeline cross-sectional area.
Flowmeter purpose:
The Turbo Flow TFG-S flowmeter is used for visiting check measurements of gas flow rate on pipelines of any material.
Field of application:
Field metering stations without stationary gas meters:
- detecting unbalance;
- periodic short-term measurements;
- monitoring and functional check of controlled meters
Specific features of flowmeter:
- Mobility;
- Measuring pipeline diameter from 50 mm to 1,400 mm;
- Simple mounting on site
Merits:
- High accuracy: relative measurement error not more than 1% throughout the range of operating flow rate, which allows assessing the confidence of readings of the checked meter;
- Wide dynamic measurement range 1:600. Allows monitoring with a wide range of gas flow rate;
- Possibility of operational measurements;
- The possibility of monitoring without coordination with the owner of the checked complex, as well as without shutdown of the process of checked equipment;
- Allows for monitoring of networks at both oil/gas producing and industrial enterprises;
- The possibility of use both with natural and associated petroleum gas (including wet);
- Cost-saving due to the possibility of using on an unlimited number of measurement points;
- High resistance to temperature overloads;
- Autonomous operation time not less than 10 hours.
Configuration options:
By sensitive element design:
Integrated / remote sensitive element for gas temperature measurement:
- Configuration 00 – for DN from 50 to 400 mm inclusive;
- Configuration 01 – for DN from 400 to 900 mm inclusive;
- Configuration 02 – for DN from 900 to 1400 mm inclusive.
Equipping:
- Available tablet;
- Available USB-port;
- Thickness gauge;
- Tape line;
- Slide gage;
- Pressure transmitter;
- Ruler.
Technical specifications:
Characteristic |
Value |
Measurement range of volumetric gas flow rate under standard conditions, m3/h |
from 1.25 to 588,000 |
Pipeline diameter, mm |
from 50 to 1,400 |
Limit of permissible relative error during measurement of volumetric gas flow rate, reduced to standard conditions, %
– using the manufacturer’s measuring section
– without using the manufacturer’s measuring section |
± 1.0 in the range 0.015 Qmax < Q < Qmax
± 2.0 in the range Qmin < Q < 0.015 Qmax
± 1.5 in the range 0.015 Qmax < Q < Qmax
± 2.5 in the range Qmin < Q < 0.015 Qmax |
Gas temperature measurement range, °С |
От минус 60°С до плюс 300°С |
Limits of permissible absolute error during temperature measurement, °С |
±(0,3+0,005|t|),
where t – measured temperature, °C |
Limits of absolute error during time measurement, s |
±1 for 24 h |
Flow speed range, m/s |
От 0,03 до 350 |
Upper limit of overpressure measurements, kPa |
up to 600
up to 32 |
Working range of overpressure measurements, % of ULM |
from 33 to 100 |
Upper limit of absolute pressure measurements, (ULM), MPa |
up to 32 |
Working range of absolute pressure measurements, % of ULM |
from 33 to 100 |
Dynamic range (Qmin/Qmax) |
1:600 |
Sensitivity threshold |
0,3 Qmin |
Limits of permissible relative error during pressure measurement, % |
±0,5 |
Performance specification::
Characteristic |
Value |
PT* operating conditions:
– ambient air temperature, °C |
From minus 60 to plus 70 |
Kind of PT* explosion protection |
Ex ib Gb [ia Ga] IIC T4 Gb
или 1 Ex dib Gb [ia Ga] IIC T4 Gb |
Kind of FMC** explosion protection |
[Ex ib Gb] IIC |
Protection degree of PT* as per GOST 14254-96 |
IP65 |
Protection degree of FMC* as per GOST 14254-96 |
IP54 |
Average mean time between failures, hours, at least |
60 000 |
* PT – primary transducer;
** FMC – flow measurement cabinet.