This article's table of contents introduction:
- What Are They?
- Core Technical Features
- Standards & Certifications (China & International)
- Typical Models & Configurations
- Key Applications
- Important Selection Criteria
- Example Manufacturers (China & Global)
- Summary for Procurement
Your request for "High-Temperature Resistant Explosion-Proof Fans" refers to a specialized category of industrial ventilation equipment designed to operate safely in environments where there is a risk of explosion, fire, or extreme heat. These are critical in industries like oil & gas, chemical processing, mining, marine engineering, and tunnel construction.
Here is a comprehensive breakdown of what these fans are, their key features, technical specifications, applications, and standards.
What Are They?
These fans combine three critical attributes:
- Explosion-Proof (Ex): The electrical and mechanical components are designed to prevent any spark, arc, or hot surface from igniting a surrounding flammable atmosphere (gas, vapor, or dust).
- High-Temperature Resistant: They can withstand and operate in ambient temperatures significantly higher than standard fans (e.g., 150°C to 400°C+, compared to standard 40-80°C). Some are designed for emergency smoke extraction (up to 300°C for 1-2 hours).
- Ventilation: They move air, fumes, or gas mixtures safely.
Core Technical Features
| Feature | Description & Importance |
|---|---|
| Motor Type | Flameproof (Ex d): The motor is enclosed in a robust housing that can contain an internal explosion without igniting the outside atmosphere. Increased Safety (Ex e): Certified for non-sparking operation. |
| Material of Construction | Impeller: Aluminum alloy (non-sparking), Stainless Steel (SS304/316 for corrosion & heat), or special high-temp alloys. Housing: Heavy-duty cast iron or steel. |
| Temperature Class | T3 (200°C), T4 (135°C), T5 (100°C), T6 (85°C) – Defines the maximum surface temperature allowed. For high-temp, T3 or special ratings are common. |
| Ingress Protection (IP) | IP55, IP56, or IP65 – High protection against dust and water jets (e.g., for marine or outdoor use). |
| Bearing System | High-temperature grease or oil-lubricated bearings. Often with external cooling fins or separate cooling fans for the motor. |
| Cable Glands | Explosion-proof cable entries (Ex d) to prevent flame propagation. |
Standards & Certifications (China & International)
- China (GB): GB 3836 series (Explosive atmospheres), particularly GB/T 3836.1 (General), GB/T 3836.2 (Flameproof enclosures). Certificates from CNEx, NEPSI, CQST are mandatory for domestic use.
- International:
- ATEX (EU): Directive 2014/34/EU. Category 2G/2D for gas/dust.
- IECEx (Global): International standard.
- UL / NFPA (US): For Class I, Division 1 or Zone 1 environments.
Typical Models & Configurations
-
Explosion-Proof Axial Flow Fans (BT35-11, CBF series):
- Best for: High airflow, low pressure, general ventilation (tunnels, warehouses, oil platforms).
- High-Temp Variant: Often used for smoke extraction with a special motor and impeller.
-
Explosion-Proof Centrifugal Fans (B4-72, B9-19 series):
- Best for: Ducted systems, high static pressure, moving heavy fumes or dust.
- High-Temp Variant: Can handle higher temperatures on the process side (e.g., drying ovens).
-
Explosion-Proof Hot Air Circulating Fans (WEX series):
- Best for: Paint spray booths, drying rooms, and ovens requiring uniform heat distribution.
Key Applications
| Industry | Typical Use Case | Temperature Requirement |
|---|---|---|
| Oil & Gas | Ventilating storage tanks, processing units, offshore platforms. | 150-250°C |
| Chemical Plants | Removing flammable vapors (acetone, hydrogen, methane). | Up to 200°C |
| Marine | Engine rooms, cargo holds (pump rooms) for flammable liquids. | 80-120°C* |
| Tunnels & Subways | Emergency smoke extraction during fire. | 250-400°C for 1-2 hrs |
| Coal Mines | Underground ventilation to dilute methane gas. | Lower temp, must be anti-static. |
| Paint & Coating | Drying ovens, spray booths (solvent vapors). | 150-300°C |
| HVAC for Hazardous Areas | Cleanrooms in pharmaceutical labs handling flammable solvents. | 60-100°C* |
Important Selection Criteria
- Hazardous Area Classification: Is it Zone 1 (high probability), Zone 2 (low probability), or Zone 21/22 for dust?
- Gas Group: Which gas is present? (e.g., IIA (propane), IIB (ethylene), IIC (hydrogen/acetylene) - IIC is the most stringent).
- Temperature Class: Must be lower than the auto-ignition temperature of the gas.
- Airflow (CFM/m³/h) & Static Pressure (Pa): As with any fan.
- Ambient vs. Process Temperature: Is the heat in the room or in the air being moved?
Example Manufacturers (China & Global)
-
China (Leading Suppliers):
- Shanghai Fengchen (上海风机) – Well-known for BT35 and B4-72 explosion-proof fans.
- Zhejiang Shuangyang (双阳风机) – Strong in corrosion-resistant and high-temp models.
- Nantong Hengrong (南通恒荣) – Specialist in explosion-proof for chemical industry.
-
Global:
- Greenheck (USA) – High-quality, certified explosion-proof and smoke evacuation fans.
- Systemair (Sweden) – ATEX certified, large range.
- Woods Air Movement (UK) – Tunnel and smoke extraction experts.
Summary for Procurement
If you are looking to purchase or specify these fans, you must provide:
- Fan type (Axial, Centrifugal, Roof).
- Air volume (m³/h or CFM) and pressure (Pa or in. wg).
- Hazardous Gas/Dust Type & Group.
- Maximum ambient and process temperature.
- Required standard (ATEX, IECEx, GB).
- Voltage & frequency (e.g., 380V/50Hz/3Ph).
Safety Note: Using a non-certified fan in a hazardous area is illegal and extremely dangerous. Always check the certification mark and ensure it matches your specific area classification.
Would you like me to provide sample specifications, pricing estimates, or supplier recommendations based on a specific country or industry?
