Coriolis flow meters for CNG (methane) refueling

The measurement relies on the Coriolis effect: the sensor tubes vibrate, and the gas flow shifts their oscillation phase. The phase shift is proportional to the mass passing through the sensor per unit of time, so the meter outputs flow directly in kilograms — no density conversions. Readings are independent of gas pressure and temperature.

The meter is installed in the delivery line — between the dispenser valve and the refueling nozzle. It measures the mass of gas delivered into the cylinder and transmits the flow rate and totalizer to the dispenser controller, which derives the volume at standard conditions and the price.

The P version is rated up to 45 MPa depending on size, the PK series — up to 96 MPa. Typical refueling lines of 250–350 bar (25–35 MPa) are covered with a margin: the meter never operates at its limit.

Nominal flows of CNG dispensers reach tens of kilograms per minute. For such lines the range offers DN08 (up to 1,200 kg/h), DN15 (up to 3,600 kg/h) and DN25 (up to 12,000 kg/h) depending on size. The exact size is selected by working flow, pressure and connection type.

Gas volume strongly depends on pressure and temperature: conditions in the cylinder and on the line change constantly, so volumetric metering without conversion to standard conditions accumulates a systematic error. Gas mass does not depend on these conditions — that is why mass measurement has become the standard for CNG accounting.

The dispenser controller computes the volume converted to standard conditions (20 °C, 101.325 kPa per GOST 2939-63) from the gas mass and composition parameters. Mass-EXPERT volume conversion error is ±0.75% when the gas composition is known.

Within the working range from the transitional flow rate Qtr to maximum, the gas error is ±0.5–1.0% depending on size. Below Qtr it grows as δ = ±(0.5…1.0 + 100·Zs/QM)%, where Zs is zero stability. That is why the size is selected so that the meter operates within its working range during most of the refueling.

Yes. Mass measurement is independent of flow profile: pulses and surges when storage bank lines switch do not turn into systematic error. The total mass delivered per refueling, shift and day remains accurate — and settlements are based on it.

The meter is designed for vibration loads per GOST R IEC 60068-2-6 (5–55 Hz, 0.35 mm amplitude, 5 cycles along three axes), and digital signal processing filters out external noise. Vibration of CNG station equipment does not distort readings.

No: gas mass is independent of temperature. As methane expands it cools down (Joule–Thomson effect), and the built-in temperature sensor shows the actual medium condition. The P version is rated for medium temperatures from −50 °C, so winter operation is a normal mode.

For mass — no: it is a direct measurement and needs no compensation. Pressure and temperature are only required to compute the volume at standard conditions, which the meter calculates from the specified gas composition parameters.

The ME100 transmitter is marked Ex db ib IIC T6 Gb, the ME200 — Ex db ia IIC T6 Gb, with a dust variant Ex ia tb IIIC T80 °C Db. The sensor is connected to the transmitter by an intrinsically safe circuit. The IIC marking covers group IIA and IIB gases, which include methane.

Through standard interfaces: RS-485 (Modbus RTU), pulse or frequency output, 4–20 mA with HART, CAN. The controller receives the instantaneous flow rate and totalizer; the Modbus register map is provided for integration.

No. Data goes to the dispenser electronics, so a version without a display is ordered — the housing is more compact and takes no space on the front panel. A display version is available if local indication is needed during commissioning.

No. Coriolis measurement does not need flow conditioners: the meter is installed directly into the delivery line. This matters in a dispenser where piping space is limited, and replacing a meter on an existing line requires no pipe rework.

Measuring tubes — 316L stainless steel. Connections: high-pressure fittings and 13/16–16 UNF thread, GOST and ANSI flanges depending on size. The exact option is selected for the dispenser piping.

Up to 100:1 in flow rate. The refueling cycle “start — dose — stop” fits into this range: the meter measures both the beginning of supply and the main dose reliably. The size is selected by the maximum line flow.

Yes, Mass-EXPERT is entered in the Federal Register of Measuring Instruments (State Register) under No. 98506-26. This opens the way to measurements subject to metrological requirements, including commercial settlements.

Verification follows procedure MP 98506-26. It can be performed on a reference flow rig or on site — using a compact prover or reference meters, without sending the instrument away.

Compatibility is checked by mounting and connection dimensions — on high-pressure lines, primarily flanges and fittings. If the site uses Micro Motion CNG050 or Endress+Hauser CNGmass meters, replacement is possible, and in many cases it is done without welding.

For gas, the error is ±0.5–1.0% depending on size. Every meter is calibrated individually on a flow rig, and the characteristics are fixed in the type description No. 98506-26.

The minimum reliably measured quantity is determined by the transitional flow rate Qtr of the size: below it, the error grows. For lines with small doses, smaller sizes are selected (e.g., DN08) so that the working dose stays within the main range.

Station throughput, the share of disputed transactions, over-delivery losses and maintenance cost. The effect is estimated from your data: send us the line parameters and station operating profile — we will prepare an estimate and select the configuration.

Transmitters operate from 19.2–28.8 V DC, power consumption up to 20 W. An AC mains power option is available on request.

The stainless steel housing provides IP66/IP67 protection, and operating conditions cover ambient temperatures from −60 to +70 °C (transmitter, per the type description). This covers the climate from Siberia to southern regions.

The meter has no moving or wearing parts — no routine maintenance is assigned. Average service life is 20 years, mean time between failures — 100,000 hours. The metering point runs without scheduled shutdowns.

Warranty is 18 months from delivery or 12 months from installation, whichever expires first. Documentation is provided with the meter: type description, operating manual, verification procedure.

Yes, the company is a Russian manufacturer based in Ufa: installation supervision, commissioning, service and verification are performed in Russia. The meter does not depend on imported supplies or logistics.

The mass flow meter with its passport and operating manual. Mating flanges with fasteners and gaskets are available as an option; the scope is confirmed when ordering for a specific line.

Send us the line parameters — working pressure, flow rate, temperature, connection type and installation area — or fill in the questionnaire and configurator on the site. We will select the sensor, version and transmitter and prepare a quotation.