Current position > Contact Us
Quick Answer: Commercial gas delivery and allocation systems need one flow meter at every branch or take-off point. Silver Instruments supplies thermal mass, vortex, and Coriolis gas flow meters for natural gas, LPG, biogas, nitrogen, and compressed air. Most allocation jobs use 4-20 mA HART output, RS485 Modbus, and a local totalizer.
In many plants one main gas header supplies several tenants or production lines. Each user needs accurate consumption data for billing or internal cost allocation. The meter is the tracking point for commercial gas delivery. We have seen this on customer sites many times.
A food processing park in Vietnam may supply LPG from one central tank to five factories. A textile plant in Bangladesh may distribute natural gas to three boilers. Without a flow sensor at each branch no one knows which unit used 800 Nm3/h and which used 120 Nm3/h. Allocation errors increase cost and cause disputes. A flow meter with pulse output or Modbus sends consumption data to the control room automatically.
The right meter depends on gas type, pressure, pipe size, and accuracy requirement.
Thermal mass flow meters work well for dry clean gases. They measure mass flow directly in Nm3/h or kg/h. No temperature and pressure compensation is needed. Common sizes are DN15 to DN100. Accuracy is about 1.0 to 1.5 percent of reading.
Vortex flow meters handle higher flow rates and wet gas better. They measure volumetric flow. With an integrated pressure and temperature sensor they can output mass flow or standard volume flow. Typical sizes are DN25 to DN300. Pressure ratings up to 40 bar are common.
Coriolis mass flow meters give the best accuracy. They measure mass flow directly and also output gas density. Accuracy of ±0.5 percent of reading is normal. They suit high value gas such as LPG, butane, and propane in custody transfer. Pipe sizes from DN15 to DN80 cover most commercial gas delivery lines.
A customer in Vietnam asked us for a gas allocation solution last year. They had one LPG vaporizer feeding three paint production lines. We supplied three Silver Instruments thermal mass flow meters with DN40 wafer bodies. Each meter had 4-20 mA HART output and RS485 Modbus. Flow range was 20 to 400 Nm3/h. Gas pressure was 2 to 4 bar. Gas temperature was 25 to 35 °C. Totalizer data went to a local PLC. The plant now reads daily usage per line and generates internal cost reports. Payback was under four months.
Silver Instruments thermal mass gas flow meter covers DN15 to DN100. It measures gas flow from 0.5 to 3000 Nm3/h depending on pipe size. Outputs include 4-20 mA, pulse, and RS485 Modbus. Optional ATEX Exd IIC T4 certification fits Zone 1 and Zone 2 gas areas.
Silver Instruments vortex flow meter covers DN25 to DN300. It handles gas pressure up to 40 bar and gas temperature up to 250 °C. Integrated temperature and pressure compensation gives standard volume flow and mass flow. Output options include 4-20 mA HART and Modbus RTU.
Silver Instruments Coriolis mass flow meter covers DN15 to DN80. Accuracy is ±0.2 to ±0.5 percent of reading. It suits LPG, butane, propane, and LNG allocation. The meter outputs mass flow, density, and temperature. It has 4-20 mA HART and RS485 Modbus as standard.
Most engineers skip this part and then face problems during startup. In practice you need six data points before requesting a price. Gas type is the first point. Natural gas, LPG vapor, biogas, nitrogen, and compressed air have different density and thermal properties. Pipe size is the second point. Small branch lines usually fall between DN15 and DN80. Main headers often run DN100 to DN300. Flow range matters more than pipe size. Give the minimum, normal, and maximum flow in Nm3/h or kg/h. Pressure and temperature are also important. Finally specify the output signal. Most allocation systems use 4-20 mA HART plus Modbus RTU. Some custody transfer jobs need pulse output for a flow computer. Hazardous area rating is another key point. Many gas metering points sit in Zone 1 or Zone 2. Tell us the area classification and the required protection type. We can provide ATEX or IECEx versions.
Check that the gas is dry enough for the selected meter. Thermal mass meters need a straight run of 15 pipe diameters upstream and 10 diameters downstream. Vortex meters usually need 20 diameters upstream and 10 diameters downstream. Coriolis meters do not need straight runs but they need proper pipe support to avoid vibration. LPG vapor may contain liquid droplets if the vaporizer is undersized. That can damage a thermal mass sensor. Use a vortex meter or a Coriolis meter in wet gas conditions.
Which gas flow meter is best for commercial gas allocation?
A thermal mass flow meter suits dry clean gas in branch lines from DN15 to DN100. For high accuracy or custody transfer use a Coriolis mass flow meter. For main headers or higher flow rates use a vortex flow meter.
Can one flow sensor track gas for multiple users?
No. Each take-off point or tenant line needs its own flow meter. A single meter at the main inlet only records total consumption. Allocation requires one meter per branch.
Do Silver Instruments gas flow meters support Modbus?
Yes. Most Silver Instruments gas flow meters support RS485 Modbus RTU and 4-20 mA HART. Pulse output is optional for totalizer or flow computer connection.
What information do you need for a gas flow meter quote?
Send us your gas type, pressure in bar, temperature in °C, pipe size DN, and flow range in Nm3/h or kg/h. Tell us the output signal and hazardous area requirement if any.
Can these meters be used in ATEX Zone 1?
Yes. Silver Instruments offers ATEX Exd versions for thermal mass, vortex, and Coriolis gas flow meters. Specify the zone and gas group when requesting a quote.
Send your gas type, pressure, temperature, pipe size, and flow range to our engineers. We will recommend one model and provide a price with lead time. Contact Silver Instruments by Tel: +86-25-68650347. For faster response use Whatsapp: +86-25-52155837 or WeChat: +86 15365082610. Visit flow-meter.com.au to see the full gas flow meter range.
