English
DN10 Compact Coriolis | 500 psi (34.4 bar) | ATEX Approved | Canada R&D Application
A DN10 Coriolis mass flow meter (SH-CMF-10) is the correct choice for metering refrigerant R454B at flow rates around 0.454 m3/h, with operating pressure up to 34.4 bar and temperature in the 40-45 degC range. The compact design with 4-20 mA, HART, and RS485 outputs covers most R&D data-logging requirements. ATEX Zone 1 certification is standard for refrigerant lab environments.
Refrigerant R458 mass flow measurement
Simon, a product development engineer in La Pocatiere, Quebec, sent us a one-line brief: he needed a flow meter for R454B refrigerant, 2 GPM max, 500 psi working pressure, lab environment. That was it. No pipe spec, no hazardous area classification, no mention of the A2L flammability rating.
We see this regularly. R&D teams building refrigeration test rigs often treat the flow meter as an afterthought. They size the compressor, design the heat exchanger circuit, spec the pressure relief valves, and then at the final step ask what meter to use. The answer here was not obvious.
R454B is not R410A. It is an HFO/HFC blend with a GWP of 466 and an A2L flammability classification, meaning mildly flammable. A standard non-certified meter installed in a sealed lab with a refrigerant leak risk is not acceptable. That narrows the shortlist fast.
| Fluid | Refrigerant R454B (HFO/HFC blend, GWP 466) |
| Pipeline size | 1/2 inch (DN10 specified due to low flow rate) |
| Flow range | 2 GPM = 0.454 m3/h (max) |
| Operating temperature | 40 to 45 degC |
| Operating pressure | Max 500 psi = 34.4 bar |
| Output required | 4-20 mA, Pulse, RS485, HART |
| Hazardous area | ATEX Zone 1 required |
| Accuracy class | 0.2% |
| Power supply | 24V DC |
| Wetted material | 316L stainless steel |
At 0.454 m3/h, this is a small flow rate. Fitting a DN15 or larger meter here would push the flow velocity into the lower 10-15% of the meter's range and hurt accuracy. We recommended DN10(3/8”) precisely because the full-scale range of the SH-CMF-10 is 0-1500 kg/h, and the customer's actual flow sits comfortably in the midrange where Coriolis accuracy is best.
Coriolis meters measure mass flow directly. For refrigerant work, this matters. R454B density changes significantly with temperature and pressure, so volumetric meters require real-time density correction to give you mass flow. Coriolis skips that correction entirely. What you read is what you get.
R454B is mildly flammable (A2L classification). The customer's lab qualifies as a hazardous area. A standard meter without explosion protection is not an option. The SH-CMF-10 ships with ATEX Zone 1 approval as a standard configuration, not an expensive add-on.
The full model string for this application:
SH-CMF-10-P2-H1-T1-O1/O2-C2/C3-E1-A2-B1-P1-M1-PC1
| SH-CMF | Silver Coriolis Mass Flow Meter |
| 10 | DN10, flow range 0-1500 kg/h |
| P2 | Pressure rating 4.0 MPa (40 bar) |
| H1 | Compact integrated display |
| T1 | Temperature range -50 to 150 degC |
| O1/O2 | 4-20 mA and Pulse output |
| C2/C3 | RS485 and HART communication |
| E1 | ATEX explosion-proof approved |
| A2 | Accuracy class 0.2% |
| B1 | Transmitter ambient: -20 to 50 degC |
| P1 | 24V DC power supply |
| M1 | 316L stainless steel wetted parts |
| PC1 | Process connection: 1/2" SAE flare fittings |
Turbine flow meter: Cannot handle two-phase or near-saturation refrigerant flow. Bearing wear with low-lubricity refrigerants is also a known issue.
Oval gear flow meter: Works for high-viscosity liquids but is not suitable for low-viscosity refrigerants. Clearance leakage at low viscosity degrades accuracy significantly.
Vortex flow meter: Minimum flow requirements for reliable vortex shedding are too high for this application. At 0.454 m3/h in DN10, you are below the Reynolds number threshold.
Thermal mass flow meter: Calibrated for gases. Not appropriate for liquid refrigerant metering.
Send us the following parameters and we will return a model code and price within one business day:
• Fluid name and phase (liquid / gas / two-phase)
• Flow range (kg/h or m3/h)
• Operating pressure (bar or psi)
• Operating temperature (degC)
• Pipe size and connection type
• Hazardous area classification (if any)
Contact: sales@silverinstruments.com | silverinstruments.com
