This article's table of contents introduction:
- "Boiler Air Inlet 1989pa"
- "Centrifugal Extractor Fan"
- "Q235 Carbon Structural Steel"
- Summary of the Equipment
- Important Considerations for this Fan:
This appears to be a technical description or a specification for a component used in an industrial boiler system. Let's break down what these terms mean and the context of the equipment.
Your text likely describes a Centrifugal Extractor Fan (an ID Fan or Induced Draft Fan) used to pull combustion gases or hot air out of a boiler system.
Here is the detailed breakdown of each part of your description:
"Boiler Air Inlet 1989pa"
- Boiler Air Inlet: This specifies the fan's location in the system. It handles the air entering the boiler's combustion chamber (or in some configurations, it pulls air from the boiler's exhaust ductwork on the "inlet" side of the fan). Often, "Air Inlet" refers to the Forced Draft (FD) fan which pushes air into the boiler, but "Extractor" usually implies it's pulling (Induced Draft).
- 1989pa: This is the Static Pressure rating of the fan. "pa" stands for Pascals.
- What it means: The fan is designed to overcome 1,989 Pascals of system resistance (ductwork, dampers, boiler tubes, chimney).
- Context: 1,989 Pa is approximately 8 inches of water gauge (inWG). This is a typical medium-static pressure rating for an industrial boiler fan. It's strong enough to handle a dirty boiler or moderate ductwork but not a high-pressure system.
"Centrifugal Extractor Fan"
- Centrifugal: This is the fan type. Unlike a simple axial fan (like a desk fan), a centrifugal fan uses a rotating impeller (wheel) to throw air outward by centrifugal force.
- Why: Centrifugal fans are excellent for handling dirty air (ash, fly-ash) and high static pressures. They are very robust.
- Extractor Fan: This confirms the fan's function. It extracts air or flue gas from the system. In boiler terminology, this is an Induced Draft (ID) Fan.
- Function: It creates negative pressure inside the boiler furnace, ensuring combustion gases flow correctly out of the boiler and up the chimney. It helps pull the hot gases through the heat exchanger tubes.
"Q235 Carbon Structural Steel"
This tells you the material the fan is made from.
- Q235: This is a Chinese standard (GB/T 700-2006) for a common carbon structural steel grade. It is equivalent to:
- ASTM A36 (USA)
- S235JR (European EN 10025)
- SS400 (Japanese JIS G3101)
- Properties:
- Yield Strength: ~235 MPa (hence the name Q235).
- Tensile Strength: ~375-500 MPa.
- Weldability: Excellent.
- Cost: Low and widely available.
- Implication for the Fan:
- Good for: Ambient temperature air or slightly warm flue gas (below 200°C / 400°F). It's strong and durable.
- Bad for: High temperatures (requires stainless steel or alloy), corrosive gases (requires lining or stainless steel), or acidic condensation (will rust quickly).
- Typical Use: Standard industrial boiler rooms where the flue gas temperature is relatively low (e.g., after a heat exchanger or economizer) or for ambient air inlet fans.
Summary of the Equipment
You are describing a medium-pressure (1,989 Pa) Induced Draft (ID) Centrifugal Fan made from standard A36/Q235 carbon steel.
- Application: Extracting flue gas or air from an industrial boiler system.
- Design: Durable, high-pressure fan suitable for dirty air.
- Material: Standard carbon steel, economical for temperatures below ~200°C.
- Pressure: 1,989 Pa (≈ 8 inWG).
Important Considerations for this Fan:
- Temperature: Q235 steel loses strength above 300°C (572°F) . If the boiler air inlet temperature exceeds this (e.g., handling hot flue gas directly from the furnace without cooling), this fan will fail.
- Corrosion: Q235 steel has very low corrosion resistance. If the air contains moisture or corrosive gases (e.g., from burning high-sulfur fuel), the fan will rust quickly.
- Pressure Rating: 1,989 Pa is not very high. It's suitable for a clean system or a boiler with a small pressure drop. If the boiler tubes get dirty, the fan may not have enough power to maintain draft.
Verdict: This is a standard, cost-effective industrial fan for a boiler where the air/gas is clean, dry, and relatively cool.
