Current position > Product detail
『Diaphragm Flow Meter: Positive Displacement Residential Natural Gas Submeters』Related information(clamp on meter|electromagnetic meter|venturi meterrotameter|orifice meter|ultrasonic flow meter|mass flow meter|coriolis mass flow meter|coriolis flow meter|magnetic flow meter|magmeter flow meter|magflow flow meter|mag meter flow meter|electromagnetic flow meter|vortex flow meter|turbine flow meter|thermal mass flow meter|thermal flow meter|rotameter flow meter)
Diaphragm Flow Meter: Positive Displacement Residential Natural Gas Submeters
Quick Answer: A diaphragm flow meter measures residential natural gas volume by positive displacement. Each gas fill and discharge cycle moves a fixed volume through two chambers. For apartment submetering, specify a G1.6, G2.5, or G4 meter with a pulse output or M-Bus output. Silver Automation Instruments quotes these meters when you send your flow range, inlet pressure, connection size, and required data output.
Most residential natural gas submetering jobs do not need a Coriolis mass flow meter or a thermal mass flow meter. The diaphragm meter is the standard for low flow billing because it records small loads well. A G1.6 meter covers a gas stove and a small instant water heater. Its typical measuring range is 0.016 m3/h to 2.5 m3/h.
We have seen this on customer sites many times. A 40-unit apartment in Manila usually needs 40 individual submeters plus one master meter. The submeters sit in locked gas cabinets on each floor. Each meter sends a pulse signal to a local data collector. That setup gives the building manager a clear gas bill for each tenant.
How the Positive Displacement Mechanism Works
Inside the meter, gas enters a chamber behind a flexible diaphragm. The diaphragm moves as gas fills the chamber. A slide valve switches the inlet and outlet ports. Each complete diaphragm cycle pushes a fixed gas volume through the meter. The mechanical counter or electronic index records the number of cycles.
This method is direct measurement. It is not inferential like a turbine meter or vortex meter. Because each cycle represents a known volume, accuracy stays stable at low flow. A typical diaphragm gas meter has accuracy class 1.5 under OIML R 137 or EN 1359.
In practice, the diaphragm meter tolerates dust and moisture. It does not need a long straight pipe run. That is a big advantage in crowded residential gas risers.
Key Specifications for Residential Natural Gas Submeters
Match the meter size to the connected appliance load. A G1.6 meter is common for a cooking-only apartment. A G2.5 meter is better when a gas water heater is present. A G4 meter suits larger homes or small commercial kitchens.
Typical specifications to confirm before quotation:
Flow range: 0.016 m3/h to 2.5 m3/h for G1.6. 0.025 m3/h to 4.0 m3/h for G2.5. 0.040 m3/h to 6.0 m3/h for G4.
Connection size: DN15 or DN20 with G1/2 or G3/4 threads.
Maximum working pressure: 0.5 bar for standard residential meter bodies.
Temperature range: -10 °C to 40 °C.
Output options: dry contact pulse, M-Bus, RF 433 MHz, or LoRaWAN.
Display: mechanical index or LCD display.
Do not oversize the meter. A G4 meter on a single gas stove may not register the minimum flow accurately. Engineers sometimes skip this part and then wonder why the meter total does not move.
Residential Submetering Setup and Data Output
Submetering means the building owner buys gas in bulk and bills each tenant based on actual use. The diaphragm meter measures each unit. The pulse output sends a signal to a data concentrator or building management system.
A typical pulse constant is 0.01
_600x400.jpg)
Because billing disputes are common, the meter should have a tamper resistant lead seal and a clear mechanical index. The electronic output is for data collection. The mechanical counter is the legal reference.
Why Diaphragm Meters Fit Residential Gas Submetering
Diaphragm gas meters are not the same as industrial Coriolis mass flow meters or thermal mass flow meters. Those instruments are for high accuracy or low flow gas measurement in industrial processes. For residential gas billing, the diaphragm meter is less expensive and easier to maintain.
But there are limits. Diaphragm meters are bulky compared to ultrasonic gas meters. They are not suitable for pressure above 0.5 bar unless a special meter body is used. They also have moving parts and need periodic replacement after 10 to 15 years depending on local regulations.
We have seen customers in Latin America use diaphragm meters for small commercial bakeries and food stalls. The meters work well when natural gas pressure is stable and the load is a gas oven or fryer.
Supply Scope from Silver Automation Instruments
Silver Automation Instruments supplies positive displacement diaphragm gas submeters for residential and light commercial natural gas service. We work with gas utility clients, building contractors, and distributors in Vietnam, Indonesia, the Philippines, Mexico, Nigeria, and the UAE.
For a standard single apartment, request model SAI-RGM-G1.6 with dry contact pulse output. For a small cafe or bakery with a gas oven, request model SAI-RGM-G4 with M-Bus output.
Send us your flow range in m3/h, inlet pressure in bar, connection size in DN, and required output. We quote the meter body, pulse output option, and any needed data collector or commissioning support. Contact Silver Automation Instruments at Tel: +86-25-68650347, Whatsapp: +86-25-52155837, WeChat: +86 15365082610.
FAQ: Diaphragm Flow Meter for Natural Gas Submeters
What size diaphragm gas meter do I need for a single apartment?
Use a G1.6 meter for a gas stove only. Use a G2.5 meter if a gas water heater or small boiler is connected.
Can a diaphragm gas meter be used for CNG or LPG?
The meter body can measure LPG vapor in some cases, but the calibration must match the gas density. CNG is not typical for residential diaphragm meters because pressure is too high.
What is the normal working pressure for a residential diaphragm gas meter?
Standard meter bodies work at 0.5 bar or less. For higher pressure, confirm the inlet pressure before ordering.
Does a diaphragm gas meter need a flow computer?
No. The mechanical index is direct reading. A flow computer is only needed if you require temperature and pressure compensation for billing.
What output option do you recommend for apartment submetering?
M-Bus is reliable for new buildings. RF 433 MHz or LoRaWAN is often easier for retrofit projects in occupied buildings.