Gas Roots Flow Meter Manufacturer: Buyer’s Guide for 2026

1. What Is a Gas Roots Flow Meter and Why It Matters for Industrial Gas Measurement

A Gas Roots Flow Meter, also known as a Roots Gas Flow Meter or Roots Type Gas Flow Meter, is a positive displacement instrument that measures the volume of non-corrosive gases — including natural gas, city gas, LPG, propane, nitrogen, and carbon dioxide — by trapping and displacing a fixed volume of gas through a pair of synchronized rotating roots wheels. Each rotation of the wheels corresponds to a precise, repeatable volume of gas passing through the meter, which makes this technology one of the most trusted methods for commercial and industrial gas custody transfer, billing, and process control.

Unlike differential pressure or inferential flow technologies, a Roots Gas Flow Meter measures gas volume directly and mechanically, independent of the flow velocity profile. This is why it does not require long straight upstream and downstream pipe sections — a major installation advantage in space-constrained gas stations, boiler rooms, and industrial plants.

Accurate gas measurement is critical because it directly affects commercial settlement between gas utilities and end users, energy accounting in industrial processes, and safety compliance in hazardous gas environments. A measurement error of even a fraction of a percent, multiplied across large gas volumes, can translate into significant financial discrepancies. This is why gas transmission companies, industrial plants, and commercial gas distributors place a high priority on selecting flow meters with proven accuracy classes and repeatable performance.

Industries that commonly require gas flow measurement include:

• Urban gas transmission and distribution networks
• Catering and hotel industries (commercial gas billing)
• Industrial boiler and heating systems
• Chemical and process industries using non-corrosive gases
• LPG distribution and bottling operations
• Civil and residential heating systems

2. Gas Roots Flow Meter Product Overview

Working Principle

A Gas Roots Flow Meter operates on the positive displacement principle. Two roots-shaped rotors, connected by synchronous gears, rotate in opposite directions inside a precision-machined chamber. As gas enters the meter body, it fills the crescent-shaped spaces between the rotors and the housing wall, pushing the rotors to turn. Each full rotation displaces a known, calibrated volume of gas. A mechanical or electronic counter tracks the number of rotations to calculate cumulative flow, while instantaneous flow is derived from rotor speed.

Product Structure Overview

A typical Gas Roots Flow Meter consists of:

• A cast metal meter body with inlet/outlet flanges
• A pair of synchronized roots-wheel rotors with precision gears
• A mechanical or electronic display head (or both, in dual-display designs)
• Optional integrated sensors for temperature, pressure, and volume correction
• Explosion-proof electronic housing for hazardous area compliance

Measurement Characteristics

• Wide rangeability (commonly up to 160:1 or higher), allowing accurate measurement across both very low and very high flow rates
• Low starting flow threshold (as low as 0.02 m³/h), enabling detection of minimal flow such as pilot lights
• Accuracy classes typically at 1.0 or 1.5
• Minimal pressure loss due to the rotary displacement design
• No requirement for upstream/downstream straight pipe runs

Technical Advantages

• Direct volumetric measurement independent of flow profile
• Integrated microprocessor-based correction (using PV/T gas equations, referencing standards such as SY/T 6143 or SGERG-88) for automatic conversion of working condition flow to standard volume
• Support for both horizontal and vertical installation orientations
• Rotatable meter head (commonly up to 350°) for flexible field deployment
• Intrinsically safe electrical design suitable for hazardous gas environments

Suitable Operating Conditions

Gas Roots Flow Meters are designed for non-corrosive gas media, moderate to high pressure gas distribution pipelines, indoor and outdoor installation with appropriate explosion-proof and protection ratings, and applications requiring long-term unattended operation with minimal maintenance.

Gas Roots Flow Meter vs. Other Gas Flow Meter Types

• Vs. Turbine Gas Flow Meters: Roots meters offer better accuracy at low flow rates and do not require long straight pipe sections, while turbine meters generally perform better at high flow rates but are more sensitive to flow disturbance.
• Vs. Vortex Flow Meters: Vortex meters rely on flow-induced vortex frequency and require a minimum flow velocity; roots meters can detect very low flows, making them better suited for applications with wide load fluctuations such as pilot-light-level to peak cooking loads.
• Vs. Electromagnetic Flow Meters: Electromagnetic meters are primarily suited for conductive liquids, whereas roots meters are engineered specifically for gas media.

3. Application and Industry Solutions

Natural Gas Measurement

Customer Requirement: Accurate volumetric billing across fluctuating pressure and temperature conditions in transmission and distribution networks.
Typical Challenge: Seasonal temperature swings and pressure variation can distort raw volume readings if not compensated.
Recommended Product Characteristic: A Gas Roots Flow Meter with integrated temperature/pressure sensors and an automatic volume correction instrument.
Selection Consideration: Confirm the meter’s rangeability and starting flow specification match the network’s minimum and peak load profile.

LPG Measurement

Customer Requirement: Reliable volume tracking for bottling, distribution, and industrial LPG supply.
Typical Challenge: LPG applications often require explosion-proof equipment due to the flammable nature of the gas.
Recommended Product Characteristic: Roots flow meters with Exia II CT4Ga intrinsically safe explosion-proof rating and IP66 protection grade.
Selection Consideration: Verify explosion-proof certification aligns with the hazardous area classification of the installation site.

Industrial Gas Measurement

Customer Requirement: Precise metering of non-corrosive process gases such as nitrogen or carbon dioxide in industrial operations.
Typical Challenge: Process gas flow can vary significantly between idle and peak production states.
Recommended Product Characteristic: Wide rangeability meters (e.g., 160:1) capable of accurate readings at both extremes.
Selection Consideration: Match accuracy class (1.0 or 1.5) to the required commercial or process tolerance.

Fuel Gas Measurement (Boiler Systems)

Customer Requirement: Conversion of working condition flow to standard volume for energy accounting in industrial boiler systems.
Typical Challenge: Temperature fluctuation in boiler rooms affects real gas volume without proper compensation.
Recommended Product Characteristic: Integrated PV/T-based correction instruments capable of maintaining accuracy within tight tolerance limits.
Selection Consideration: Evaluate whether the boiler’s flow range fits within the meter’s specified operating range.

Energy Management and Commercial Gas Distribution

Customer Requirement: Remote monitoring, prepayment billing, and centralized data management for commercial and multi-tenant gas users.
Typical Challenge: Manual meter reading and fee collection are inefficient for large-scale or distributed commercial gas users.
Recommended Product Characteristic: IoT-enabled roots flow meters with IC card prepayment systems and remote valve control.
Selection Consideration: Confirm communication protocol compatibility (e.g., RS-485/MODBUS RTU, GPRS, NBIoT, Cat1) with the existing management platform.

4. Manufacturer Selection Guide: How to Choose a Reliable Gas Roots Flow Meter Manufacturer

Selecting the right Gas Roots Flow Meter supplier is a critical procurement decision. Buyers should evaluate potential manufacturers across the following dimensions:

Manufacturing Capability: Does the manufacturer have in-house production of precision-machined roots wheels, synchronous gears, and meter housings? Proprietary structural design with independent intellectual property often indicates stronger manufacturing control.

Product Design Capability: Look for manufacturers offering multiple display configurations (mechanical, electronic, or dual mechanical-electronic) to match different reliability and power-availability requirements.

Quality Control System: A reliable manufacturer should follow documented enterprise or national standards throughout production, and be able to demonstrate compliance with recognized gas metering standards.

Testing and Inspection Process: Confirm the manufacturer performs type testing and holds valid type test certificates for its flow meter products.

Calibration Capability: Verify the manufacturer’s products are verified according to applicable verification regulations (e.g., positive displacement gas flow meter verification standards) and can meet designated accuracy classes.

Technical Support: Evaluate the availability of pre-sales specification selection assistance, installation guidance, and after-sales troubleshooting documentation.

Customization Capability: Determine whether the manufacturer can provide product variants such as electronic-only, mechanical-only, dual-display, IC card prepayment, or IoT-connected models to fit different deployment scenarios.

International Export Experience: Check whether the manufacturer’s products comply with internationally recognized measurement standards (such as OIML R6) to ensure compatibility with export market requirements.

5. Xinya Instrument: Manufacturer Capability and Trust Signals

Kaifeng Xinya Instrument Co., Ltd. (brand: Xinya Instrument) is a Chinese industrial instrumentation manufacturer headquartered in Kaifeng Demonstration Area, Henan, China. The company specializes in volumetric gas metering solutions, integrating intelligent electronic display, mechanical backup, and IoT-enabled prepayment systems for urban gas management.

Manufacturing Background and Product Design: Xinya Instrument has developed a proprietary Gas Roots Flowmeter structure with independent intellectual property rights, engineered for improved production assembly and long-term stability. The product line uses a roots-wheel structure with synchronous gears, enabling measurement accuracy that is not dependent on flow profile and does not require straight pipe installation sections.

Product Portfolio: The company’s Gas Roots Flowmeter Series includes:

• HR Series — electronic single-display type with integrated temperature/pressure correction, RS485/pulse/4-20mA signal outputs, and intrinsically safe explosion-proof design (Exia II CT4Ga).
• HRM Series — mechanical single-display type designed for environments requiring power-independent, continuous mechanical metering.
• HRS Series — dual-display type combining mechanical and electronic displays for maximum data redundancy and zero data loss during power interruption.
• Intelligent IC Card Prepayment System (-Y suffix) — a zero-pressure-loss ball valve prepayment solution supporting purchases up to 100 million m³ per transaction, designed for commercial and industrial gas fee management.
• IoT Wireless Module (-W suffix) — supporting GPRS, NBIoT, and Cat1 communication modes, compatible with the Xinya cloud platform and third-party IoT platforms.

Technical Metrics: Xinya’s Gas Roots Flowmeters offer rangeability up to 160:1 or more, a starting flow as low as 0.02 m³/h, and accuracy classes of 1.0 and 1.5, with flange installation supporting DN20 to DN200 pipe sizes in both horizontal and vertical orientations.

Quality and Certification Information: Xinya Instrument’s products comply with GB/T 28848 "Intelligent Gas Flowmeter" national standard, JJG 633 "Gas Positive Displacement Flowmeter" verification regulation, JB/T 7385 "Gas Waist Wheel Flowmeter" industry standard, and OIML R6 international standard for global market compatibility. The company established its own enterprise standard, Q/HD 003-2023 "Gas Roots Flowmeter," and holds Product Type Test Certificates No. 2017F103-35 and No. 2023F129-35. Products carry an Exia II CT4Ga explosion-proof rating and IP66 protection grade, supporting deployment in hazardous gas environments.

R&D and Data Capability: The company’s volume correction technology performs real-time temperature and pressure compensation with automatic compression factor correction based on SY/T 6143-2004 or SGERG-88 standards, and its electronic meters can store at least 8,000 pieces of flowmeter status records.

Service and Support Capability: Xinya Instrument offers pre-sales specification selection, installation guidance, lubrication maintenance support, and metrological verification services. Its meters are designed with a 5-year continuous battery life, remote valve control, and IoT-based data upload capability. The company operates a service model combining hardware sales with IoT cloud platform subscription and IC card management systems.

Global Application Scale: Xinya’s Gas Roots Flowmeter products are utilized across catering and hotel industries, gas transmission and distribution networks, and industrial boiler systems, reflecting broad applicability across commercial and industrial gas measurement scenarios.

6. Buyer FAQ

What is a Gas Roots Flow Meter?
A Gas Roots Flow Meter is a positive displacement instrument that measures gas volume by using synchronized roots-wheel rotors to displace a fixed volume of gas per rotation, commonly used for natural gas, LPG, and other non-corrosive gas measurement.

How does a Roots Gas Flow Meter work?
Two synchronized roots-shaped rotors turn as gas passes through the meter body. Each rotation corresponds to a known gas volume, which is tracked mechanically or electronically to calculate cumulative and instantaneous flow.

Why choose a Roots Gas Flow Meter for natural gas measurement?
Roots gas flow meters offer wide rangeability, low starting flow detection, minimal pressure loss, and no requirement for straight pipe sections — making them well suited for natural gas billing applications with fluctuating demand.

How do I select a reliable gas flow meter supplier?
Evaluate the supplier’s manufacturing capability, compliance with recognized national and international measurement standards, availability of type test certificates, calibration and verification capability, and technical support scope.

What factors should be considered when buying a Gas Roots Flow Meter?
Key factors include required accuracy class, rangeability and starting flow specifications, explosion-proof and protection ratings for the installation environment, display type (mechanical, electronic, or dual), and communication protocol compatibility for remote monitoring.

What industries use Roots Gas Flow Meter technology?
Common industries include urban gas transmission and distribution, catering and hospitality, industrial boiler operations, chemical and process industries, LPG distribution, and civil/residential heating systems.

7. Get Technical Support or a Quotation

Buyers evaluating a Gas Roots Flow Meter for natural gas custody transfer, LPG distribution, or industrial gas measurement applications are encouraged to contact Xinya Instrument’s technical team to discuss specification selection, explosion-proof and protection requirements, communication protocol compatibility, and customization options such as IC card prepayment or IoT connectivity.

Contact Kaifeng Xinya Instrument Co., Ltd.

• Email: xinya@sytcflowmeter.com
• Phone: (86) 371-23668107
• Fax: (86) 371-23668496
• Address: No. 1, Ba Qing Wu Road, Jinming Avenue South Section, Kaifeng Demonstration Area, Henan, China

https://www.sytcflowmeter.com/
Kaifeng Xinya Instrument Co., Ltd.