Product Overview
The HFM Thermal Mass Gas Flow Meter operates based on the heat transfer principle and is specially designed for measuring stable gas media. It uses a pair of platinum resistance temperature sensors to form a measurement circuit: one sensor continuously monitors the real-time gas temperature, while the other maintains a constant temperature differential above the gas temperature.By analyzing the heat dissipation caused by gas flow, the device accurately calculates mass flow rate. Its core advantage is that it does not require additional temperature and pressure compensation, and can directly output volumetric flow or standard-condition mass flow.With no moving parts, the meter is suitable for a wide measuring range from low to high flow velocities. It is widely used in gas energy management, energy efficiency monitoring, environmental monitoring, process control, and large-area airflow measurement in HVAC systems.
Product Features & Advantages
- Direct Mass Flow Measurement: Directly measures gas mass flow without being affected by temperature and pressure fluctuations, eliminating the need for additional compensation devices and reducing system cost and measurement error. Standard-condition flow data can be read directly.
- Wide Velocity Range: Measuring range from 0.5 to 100 Nm/s, with customized versions down to 0.1 Nm/s. Capable of accurately detecting low-speed flows such as micro-leakage while maintaining stable performance under high flow conditions. Accuracy reaches ±1% with excellent repeatability.
- Durable Sensor Design: Constructed with corrosion-resistant materials such as 316L stainless steel. No moving parts or pressure sensing components, offering strong vibration resistance and high durability against particulate contamination.
- Flexible Installation: Supports insertion-type installation with a ball valve base, enabling installation and maintenance without process shutdown, significantly reducing operational downtime.
- Advanced Digital Circuit Design: Strong electromagnetic interference resistance. Optional intrinsically safe or explosion-proof enclosure designs available for hazardous environments. Protection rating up to IP67 for harsh outdoor conditions such as humidity and dust.
- Flexible Communication Interfaces: Standard 4–20mA output, with optional RS485 (Modbus protocol) and HART protocol. Easily integrates with industrial control systems such as PLC, DCS, and SCADA.
Technical Specifications
| Item | Detailed Specifications |
| Nominal Diameter | Inline type: DN10 ~ DN300; Insertion type: DN25 ~ DN2000 (customizable) |
| Accuracy Class | Inline: ±1.5%; Insertion: ±2.5% |
| Temperature Requirements | Ambient: -20°C ~ 80°C; Medium: 0°C ~ 350°C |
| Sensor Materials | Hastelloy, 316L, PTFE (Teflon) coating, PFA coating |
| Probe Diameter | Ø20 (customizable) |
| Protective Tube Material | Stainless Steel 304, 316L |
| Suitable Media | General dry gases |
| Velocity Range | 0.5 ~ 120 Nm/s |
| Pressure Range | ≤ 6.3 MPa |
| Explosion Protection Rating | Ex db IIC T6 Gb |
| Power Supply | AC 220V, DC 24V |
| Output Signals | 4–20mA, RS485, HART |
| Connection Type | Flange, Coupling, Wafer, Threaded, Insertion type |
Technical Specifications
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| Environmental Protection & Gas Emission Treatment | Energy & Power Systems | Oil & Gas and Chemical Industry |
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| Metallurgical Industry | Food & Pharmaceutical Industry | Electronics Manufacturing |
