Gas turbine flow meters are widely used for natural gas custody transfer and industrial gas measurement because of their low pressure loss, high accuracy, and wide turndown ratio. However, purchasing engineers and project managers often face a difficult choice when selecting a gas flow meter:

• International brands may offer proven accuracy and reliability, but often come with higher prices and longer spare-parts lead times.
• Chinese gas flow meter manufacturers can offer more competitive pricing, but product quality and turndown ratios vary significantly between manufacturers.

Aister Instrument (Shanghai) Co., Ltd. is a professional Chinese flow meter manufacturer specializing in gas flow measurement technologies, including thermal mass flow meters, gas turbine flow meters, and gas rotary/Roots flow meters.

The Aister ATWG series gas turbine flow meter is designed for natural gas custody transfer and industrial process gas measurement. The product range covers multiple pipe sizes from DN50 to DN400, with a turndown ratio of up to 1:30, integrated temperature and pressure compensation, compressibility-factor correction, and an ExdIIBT6 explosion-proof rating.

These features make the ATWG series a competitive alternative for buyers looking for a cost-effective gas turbine flow meter from a Chinese manufacturer.

2. Technical Fundamentals

2.1 How Does a Gas Turbine Flow Meter Work?

A gas turbine flow meter operates based on the principle of conservation of angular momentum.

When gas enters the meter, the specially designed flow-conditioning structure accelerates and directs the gas toward the turbine rotor. The gas flow generates torque on the turbine blades, causing the rotor to rotate.

Once the driving torque and resistance torque reach equilibrium, the turbine rotational speed has an approximately linear relationship with the gas flow rate.

Through electromagnetic induction, the rotating turbine periodically changes the magnetic reluctance of the sensing system, generating pulse signals that are proportional to the volumetric flow rate.

For compressible gases such as natural gas, the measured volume is strongly affected by temperature and pressure. A gas turbine flow meter equipped with temperature and pressure compensation simultaneously collects temperature and pressure signals and converts the measured operating-condition flow rate into a flow rate under a defined standard reference condition.

This compensation is particularly important when the flow meter is used for custody transfer or applications where gas consumption must be accurately calculated.

2.2 Comparison of Different Gas Turbine Flow Meter Configurations

 

Technical Parameter	Traditional Mechanical Turbine	Basic Turbine Flow Meter	Smart Temperature & Pressure Compensation Type (ATWG)
Accuracy	±2.0%R	±1.5%R	±1.0%R
Turndown Ratio	1:5	1:10	Up to 1:30
Temperature & Pressure Compensation	No	Optional	Standard, integrated
Communication	Pulse output	Pulse + 4–20 mA	Pulse + 4–20 mA + RS485/MODBUS + GPRS
Explosion-Proof Rating	None	ExdIIBT4	ExdIIBT6
Recommended Maintenance Interval	1 year	2 years	≥5 years

The Aister ATWG series is designed around the key requirements of modern gas measurement applications. Its 1:30 turndown ratio and standard integrated temperature and pressure compensation are two of its major advantages compared with conventional gas turbine flow meter configurations.

3. Aister ATWG Gas Turbine Flow Meter: Detailed Product Analysis

3.1 Key Specifications

 

Parameter	ATWG Series Specification
Nominal Diameter	DN50, DN80, DN100, DN150, DN200, DN250, DN300, DN400
Connection	Flanged connection
Accuracy	±1.5%R, ±1.0%R
Turndown Ratio	1:10, 1:20, 1:30
Display	Wide-screen display showing instantaneous flow, daily totalized flow, accumulated total flow, temperature, pressure, time, date, and battery level
Meter Body Material	304 stainless steel or cast aluminum
Turbine Material	Corrosion-resistant ABS or high-quality aluminum alloy
Display Housing	Cast aluminum
Bearings	Imported stainless-steel dust-proof instrument bearings
Temperature Sensor	Integrated
Pressure Sensor	Integrated
Measured Medium Temperature	-10°C to +100°C
Environmental Conditions	Medium temperature: -10°C to +100°C; relative humidity: 5%–90%; atmospheric pressure: 86–106 kPa
Signal Output	Three-wire pulse, three-wire 4–20 mA, RS485 protocol, IC card signal
Power Supply	Built-in lithium battery ≥5 years; external 24 VDC power supply; dual power supply
Transmission Distance	≤1,000 m
Cable Interface	M20 × 1.5 female thread
Explosion-Proof Rating	ExdIIBT6
Protection Rating	IP65

3.2 Key Features and Advantages

① 1:30 Wide Turndown Ratio

One of the major advantages of the ATWG series is its wide turndown ratio, which can reach 1:30.

• The turndown ratio can be increased from 1:10 to 1:30, significantly expanding the usable measurement range.
• A 1:30 ratio means that the meter can cover a much wider difference between minimum and maximum measurable flow rates.
• This is particularly useful in applications with large variations in gas consumption, such as urban gas networks with significant day/night demand changes or industrial boilers with intermittent operation.
• A wider turndown ratio helps maintain reliable measurement at low flow rates and reduces the risk of low-flow conditions falling outside the effective measurement range.

For Chinese gas turbine flow meter products, the 1:30 turndown ratio represents one of the key technical advantages of the ATWG series.

② Integrated Temperature & Pressure Compensation with Compressibility Correction

For natural gas custody transfer, temperature and pressure compensation is an important consideration.

The ATWG series integrates high-accuracy temperature and pressure sensors to continuously monitor changes in the gas conditions.

The system can automatically convert operating-condition volumetric flow into volumetric flow under a standard reference condition of 101.325 kPa and 20°C.

This helps compensate for measurement variations caused by changes in gas temperature and pressure.

For example, the difference between a gas temperature of 30°C in summer and -10°C in winter can theoretically cause a significant change in gas volume. Similarly, pressure fluctuations can have a major impact on the measured volume.

For this reason, temperature and pressure compensation should be strongly considered when selecting a gas turbine flow meter for custody transfer applications.

③ Dual-Power, Low-Power Design with More Than 5 Years of Battery Life

The ATWG series uses a low-power electronic design and supports multiple power supply configurations.

• The built-in lithium battery can provide more than 5 years of operation under appropriate conditions.
• External 24 VDC power is also supported for installations where an existing power supply is available.
• The dual-power configuration can provide additional power redundancy.
• The low-power circuit design allows the meter to maintain its main functions when operating from the internal battery.

This design is particularly useful for gas measurement stations where external power is limited or unavailable.

④ Integrated Smart Design with Multiple Outputs and Remote Meter Reading

The ATWG series supports multiple communication and signal output options:

• Three-wire pulse output
• 4–20 mA output
• RS485/MODBUS communication
• GPRS-based remote data transmission
• IC card-based quantity control

Through RS485 and MODBUS communication, the flow meter can be integrated into a remote data acquisition and monitoring system through communication networks.

The IC card function can also be used in prepaid gas management systems.

The integrated flow computer/display can be rotated 180°, making it easier for operators to read the display under different installation orientations.

⑤ High-Reliability Mechanical Design

Dust-Protected Sealing Chamber

The ATWG series uses a sealed chamber with a pressure-balancing design to reduce dust entering the bearing clearance.

This helps reduce bearing wear and the risk of rotor blockage, particularly when the measured gas contains a certain amount of dust.

Flow Conditioning

The flow-conditioning structure helps improve measurement reliability under less-than-ideal installation conditions and when the available upstream and downstream straight pipe sections are relatively short.

However, appropriate straight-pipe requirements should still be followed whenever possible.

High-Precision Imported Bearings

The turbine rotor uses imported stainless-steel, dust-resistant instrument bearings designed for high sensitivity, stable operation, and long service life.

Flexible Material Selection

The meter body can be manufactured from 304 stainless steel or cast aluminum.

The turbine rotor can be manufactured from corrosion-resistant ABS or high-quality aluminum alloy depending on the application and measured medium.

⑥ Individual Calibration Before Shipment

Each ATWG gas turbine flow meter undergoes inspection and individual calibration before shipment.

This provides traceability for measurement accuracy and supports applications where measurement verification is required.

Third-party verification by qualified metrology organizations in China is also supported.

3.3 Limitations and Considerations

A balanced product evaluation should also consider the limitations of the ATWG series.

Growing Brand Recognition

Compared with established brands with a long history in the international gas industry, Aister is still developing its brand recognition in some traditional gas companies.

For large international tenders, brand references and historical project records may therefore be important factors for buyers to evaluate.

Limited Experience with Very Large Pipe Sizes

The product range covers sizes up to DN400. However, compared with some long-established manufacturers, Aister has less accumulated experience with large-scale applications above DN400.

For very large-diameter projects, buyers should confirm the technical configuration and application references with the manufacturer before ordering.

Remote Monitoring Software Ecosystem

The remote monitoring platform and data analysis functions are still being developed.

Compared with the mature software ecosystems provided by some leading international brands, there may be differences in user-interface design and available data-analysis functions.

International Certification Coverage

The current product documentation primarily covers Chinese certifications and metrology-related qualifications, including CPA and explosion-proof certification.

International certifications such as CE are being developed and expanded.

For export projects, buyers should confirm the required certification package before placing an order, particularly when a project specification requires specific international approvals.

3.4 Installation and Integration

Correct installation is critical to the measurement performance of a gas turbine flow meter.

The recommended installation requirements for the Aister ATWG series include:

Straight Pipe Requirements

• Recommended upstream straight pipe length: ≥20D
• Recommended downstream straight pipe length: ≥5D
• Minimum straight pipe requirements should not be less than 2D where the installation design permits.
• The built-in flow-conditioning structure can improve measurement reliability under less-than-ideal piping conditions, but it should not be considered a replacement for proper installation.

Installation Position

• Horizontal installation is recommended.
• Pipe inclination should be ≤5°.
• The flow meter axis should be concentric with the pipeline axis.

Piping Requirements

The internal diameters of the upstream and downstream pipes should be consistent with the internal diameter of the flow meter.

The sealing gasket between the flanges should not protrude into the pipeline.

Filter

A filter is recommended upstream of the flow meter to maintain gas cleanliness and reduce the risk of particles affecting the turbine rotor and bearings.

Grounding

The flow meter should be reliably grounded.

It should not share the grounding connection of high-power electrical systems.

Explosion-Proof Installation

The explosion-proof configuration must comply with the hazardous-area requirements of the installation site.

Users should not modify the explosion-proof electrical connection or protection system without authorization.

3.5 Typical Applications

Application 1: Natural Gas Custody Transfer

Typical Challenge

Gas utilities and industrial gas suppliers require accurate measurement for commercial settlement.

Temperature and pipeline pressure can fluctuate significantly, making temperature and pressure compensation particularly important.

ATWG Solution

The ATWG series can be configured with:

• ±1.0%R accuracy
• Integrated temperature and pressure compensation
• China CPA-related metrology qualification where applicable
• Up to 1:30 turndown ratio
• DN50–DN400 pipe sizes
• IC card prepaid control
• GPRS remote meter reading

Recommended Models

• ATWG-DN80
• ATWG-DN100
• ATWG-DN150

Application 2: Compressed Air Energy Management

Typical Challenge

Many industrial facilities lack individual measurement of compressed-air consumption.

This makes it difficult to identify energy losses and evaluate energy-saving projects.

Compressed air may also contain small amounts of moisture and oil mist, creating additional requirements for meter durability.

ATWG Solution

The ATWG series can use:

• 304 stainless-steel meter body
• Dust-protected sealing chamber
• RS485 remote communication
• Integration with energy management systems

The recommended configuration can provide stable measurement for appropriately conditioned compressed air.

Recommended Models

• ATWG-DN50
• ATWG-DN80

Application 3: Explosion-Proof Gas Measurement in Chemical Plants

Typical Challenge

Chemical production facilities may contain flammable and explosive gases.

Flow meters installed in hazardous areas may therefore need appropriate explosion-proof protection, while also requiring remote monitoring and system integration.

ATWG Solution

The ATWG series provides:

• ExdIIBT6 explosion-proof rating
• 4–20 mA remote transmission
• RS485/MODBUS communication
• DCS integration

Recommended Models

ATWG-DN50 to DN200, selected according to the process pipeline size and operating conditions.

Application 4: Nitrogen and Inert Gas Measurement

Typical Challenge

Electronics, pharmaceutical, and chemical manufacturers often need accurate measurement of nitrogen consumption.

Gas temperature and flow rate may vary considerably, making a wide measurement range and appropriate compensation important.

ATWG Solution

The ATWG series provides:

• Integrated temperature and pressure compensation
• Automatic compressibility correction
• Wide turndown ratio
• Reliable measurement across varying flow conditions

Recommended Models

• ATWG-DN25
• ATWG-DN40
• ATWG-DN50

4. Aister ATWG Gas Turbine Flow Meter Product Range

The Aister ATWG series provides multiple nominal diameter options and configurable communication and power modules.
 

Size	Flange Standard	Turndown Ratio Options	Typical Application
DN50	GB/T 9119	1:10 / 1:20 / 1:30	Compressed air and nitrogen measurement
DN80	GB/T 9119	1:10 / 1:20 / 1:30	Main size for natural gas custody transfer
DN100	GB/T 9119	1:20 / 1:30	Natural gas custody transfer and chemical process measurement
DN150	GB/T 9119	1:20 / 1:30	Urban gas distribution and large industrial users
DN200	GB/T 9119	1:20 / 1:30	Gas pressure-regulating stations and large commercial/industrial users
DN250–DN400	GB/T 9119	1:20	Large gas networks and main gas transmission lines

Optional Configuration Modules

 

Configuration	Options	Description
Display	Local display	Wide-screen LCD showing instantaneous/totalized flow, temperature, and pressure
Remote Transmission	Pulse or 4–20 mA	Remote display and control-system integration
Temperature & Pressure Compensation	Integrated standard configuration	Built-in temperature and pressure sensors for automatic compensation
Signal Output	Pulse	Three-wire pulse output for PLC frequency acquisition
Signal Output	4–20 mA	Three-wire analog output for standard industrial transmission
Communication	RS485/MODBUS	Digital communication for remote networking and data acquisition
IC Card Quantity Control	Optional	Prepaid gas management: recharge before gas consumption
Power Supply	Built-in lithium battery	≥5 years battery life without external power
Power Supply	External 24 VDC	For installations with an existing power supply
Power Supply	Dual power	Lithium battery + external 24 VDC redundant power
Explosion-Proof Rating	ExdIIBT6	Explosion-proof configuration for applicable gas and chemical environments

5. FAQ: Aister ATWG Gas Turbine Flow Meter

Q1: What does a 1:30 turndown ratio mean in actual gas flow measurement?

A 1:30 turndown ratio means that the maximum measurable flow rate is approximately 30 times the minimum measurable flow rate within the specified measurement range.

For example, if an ATWG DN80 gas turbine flow meter has a maximum flow rate of 3,000 m³/h, a 1:30 turndown ratio means the meter can cover flow rates down to approximately 100 m³/h within the specified performance range.

This is particularly useful for urban gas networks where gas demand can vary significantly between nighttime and daytime.

A meter with a narrower 1:10 turndown ratio may reach the lower limit of its effective measurement range more quickly during low-demand periods.

Q2: What is the price difference between ATWG models with and without temperature and pressure compensation? Is compensation necessary?

If the gas turbine flow meter is used for custody transfer, the temperature and pressure compensation version is strongly recommended and may be required by the applicable measurement specification.

Temperature and pressure changes can significantly affect gas volume.

For example, changes in gas temperature from 30°C to -10°C can produce a substantial change in measured gas volume, while pressure changes can have an even larger effect.

A version without compensation is generally more suitable for basic process monitoring where custody-transfer accuracy is not required.

The compensated version typically costs approximately 30%–50% more than the basic configuration, depending on the selected specifications and communication functions.

For commercial gas measurement, the additional investment can be justified by reducing measurement uncertainty and improving the reliability of settlement data.

Q3: Can the ATWG series connect to a DCS system? How does remote meter reading work?

Yes.

The ATWG series supports RS485/MODBUS communication and 4–20 mA analog output.

Through the MODBUS RTU protocol, the meter can be integrated into industrial control and DCS systems.

The meter can also be connected to remote data acquisition and monitoring systems through a GPRS communication module.

Depending on the system configuration, users can remotely monitor:

• Instantaneous flow rate
• Accumulated flow
• Meter status
• Temperature
• Pressure

Remote data can be accessed through a web-based monitoring platform or other compatible interfaces.

Q4: Are the core spare parts such as bearings and turbine rotors easy to purchase?

Aister maintains spare-parts inventory in China.

Common spare parts include:

• Bearing assemblies
• Turbine rotor assemblies
• Sealing components
• Electronic circuit modules

For standard spare parts, the manufacturer states that shipments can generally be arranged within 48 hours from its China inventory, subject to stock availability.

Compared with some international brands where spare-part lead times can reach 4–8 weeks, Chinese-manufactured spare parts can provide advantages in both lead time and cost.

For example, the source article notes that a bearing kit from some imported brands can cost more than RMB 10,000, equivalent to approximately US$1,470 based on an exchange rate of around CNY 6.8 per USD.

Actual spare-part prices and delivery times should be confirmed with the manufacturer before purchase.

Q5: What is the approximate price of an ATWG DN80 or DN100 gas turbine flow meter?

The final price depends on several factors, including:

• Nominal diameter
• Turndown ratio
• Temperature and pressure compensation
• Signal output
• Communication functions
• Explosion-proof configuration
• Power supply configuration
• Other project-specific requirements

According to the original product information, the ATWG series is typically priced at approximately one-fifth to one-eighth of comparable configurations from some major international brands such as Endress+Hauser and Emerson.

Because gas flow meter pricing varies significantly according to configuration and project requirements, buyers should contact Aister Instrument for a current quotation and technical selection.

Q6: Can the ATWG series be installed outdoors? What is its protection level?

Yes.

The ATWG series has an IP65 protection rating and an ExdIIBT6 explosion-proof configuration.

For outdoor installation, appropriate protection against direct sunlight and rain is recommended.

The specified operating temperature range is -10°C to +100°C.

For export projects, buyers should confirm the applicable environmental, hazardous-area, and certification requirements of the destination country before ordering.

Q7: How often does the ATWG gas turbine flow meter need maintenance?

Under normal operating conditions, maintenance and verification are recommended approximately every two years, particularly for custody-transfer applications where periodic verification may be required.

Typical maintenance includes:

• Checking bearing operation
• Cleaning the turbine rotor and internal flow passages
• Verifying sensor accuracy
• Inspecting sealing components
• Replacing seals when necessary

Thanks to the dust-resistant bearings and sealed-chamber design, the actual maintenance interval may reach approximately 3–5 years under suitable operating conditions without major overhaul.

The exact maintenance schedule should be determined according to the gas composition, flow conditions, installation environment, and applicable metrology requirements.

Q8: Can the ATWG series measure compressed air containing a small amount of moisture?

Yes, provided the gas is properly conditioned.

An upstream filter is recommended, with a suggested filtration accuracy of ≤5 μm.

The 304 stainless-steel meter body and dust-protected sealing chamber provide good resistance to compressed air containing small amounts of moisture and oil mist.

However, if the gas contains significant liquid carryover or corrosive components, buyers should consider other Aister flow meter technologies, such as thermal mass flow meters or vortex flow meters.

6. Gas Turbine Flow Meter Selection Guide

Selecting the correct gas turbine flow meter requires more than simply matching the pipeline diameter.

The operating flow range, gas type, pressure, temperature, communication requirements, hazardous-area classification, and measurement purpose should all be considered.
 

Application	Recommended Configuration	Main Reason
Natural Gas Custody Transfer	ATWG + Temperature & Pressure Compensation + RS485 + GPRS	±1.0%R accuracy, applicable China CPA qualification where required, up to 1:30 turndown ratio, and remote meter reading
Compressed Air Energy Measurement	ATWG + Pulse / 4–20 mA	Cost-effective measurement with remote transmission for energy management systems
Chemical Process Gas Measurement	ATWG + 4–20 mA + ExdIIBT6	Explosion-proof configuration and 4–20 mA transmission to DCS
Nitrogen / Inert Gas Measurement	ATWG + Temperature & Pressure Compensation + RS485	Integrated compensation for more accurate gas consumption calculation
IC Card Prepaid Gas Management	ATWG + IC Card Quantity Control	Prepaid gas management and reduced payment risk
Factory with Existing DCS	ATWG + RS485/MODBUS	Native MODBUS communication for direct DCS integration

7. What Information Do You Need to Select the Right Gas Turbine Flow Meter?

Before selecting the final ATWG model, overseas buyers should provide the following information:

1. Pipeline size – DN or pipe diameter
2. Gas type – natural gas, compressed air, nitrogen, biogas, or another gas
3. Normal flow rate
4. Maximum flow rate
5. Minimum flow rate
6. Operating pressure
7. Operating temperature
8. Required accuracy
9. Whether custody-transfer measurement is required
10. Required signal output – pulse, 4–20 mA, RS485/MODBUS, etc.
11. Power supply – battery, 24 VDC, or dual power
12. Hazardous-area classification and explosion-proof requirements
13. Required communication or remote monitoring functions
14. Required certifications for the destination country

Providing these parameters allows the technical team to determine the appropriate meter size, turndown ratio, compensation configuration, communication interface, and explosion-proof specification.

8. Final Takeaway: Is Aister ATWG a Suitable Gas Turbine Flow Meter for Your Project?

The Aister ATWG series is designed for buyers who need a gas turbine flow meter with a wide measurement range, integrated temperature and pressure compensation, multiple communication options, and an explosion-proof configuration.

Its main advantages include:

• Up to 1:30 turndown ratio
• ±1.0%R accuracy configuration
• Integrated temperature and pressure compensation
• Compressibility-factor correction
• ExdIIBT6 explosion-proof rating
• IP65 protection
• RS485/MODBUS communication
• 4–20 mA and pulse outputs
• GPRS remote meter reading
• Built-in lithium battery with ≥5-year service life
• DN50–DN400 product range
• Multiple material and power supply options

For overseas buyers comparing Chinese gas turbine flow meter manufacturers with international brands, the most important consideration should not be the initial purchase price alone. The total cost of ownership should also include measurement accuracy, turndown ratio, spare-parts availability, certification requirements, installation conditions, maintenance requirements, communication capabilities, and after-sales technical support.

If you are planning to purchase an ATWG gas turbine flow meter, provide the pipeline size, gas type, minimum/normal/maximum flow rate, operating pressure, operating temperature, and required certification. Aister's technical team can use these parameters to recommend a suitable configuration and provide a quotation.

Contact our team for an expert consultation. Let us help you select the most efficient and cost-effective flow meter for your needs.