This article's table of contents introduction:
- Decoding the Specification
- Typical Performance Parameters (Estimated for 18.55 kW)
- Key Considerations for Sourcing or Replacement
- Common OEM / Manufacturers for such a fan
- Summary: What you need to buy
It seems you are looking for information on a centrifugal fan designed for use with an 55 kW carbon steel boiler. This is a specific industrial combustion component.
Here is a breakdown of what that specification means, typical performance characteristics, and what you should look for when sourcing or replacing this fan.
Decoding the Specification
- Carbon Steel: This refers to the fan's material of construction (housing and impeller). It is standard for boilers burning natural gas, light oil, or heavy oil. It offers good strength and weldability.
- Note: If the boiler burns high-sulfur fuels or operates in a very corrosive environment, you might need Stainless Steel (SS304/316) for the impeller, but standard "Carbon Steel" (often Q235 or similar) is the baseline.
- 55 kW: This is the motor power rating (approximately 25 HP). This is a powerful fan, indicating a large commercial or industrial boiler (e.g., a steam boiler for a factory, large district heating system, or a biomass boiler with high draft resistance).
- Boiler Centrifugal Fan: The "Centrifugal" designation means it uses a rotating impeller to accelerate air outward, creating high pressure. In a boiler context, this is almost certainly an Induced Draft (ID) fan or a Forced Draft (FD) fan.
- Likely ID Fan: The power (18.55 kW) and "Boiler" context suggest an Induced Draft fan. ID fans pull hot flue gases from the boiler through the heat exchanger and stack. They handle hot (often 150°C-250°C) and dusty air.
- Possible FD Fan: A Forced Draft fan pushes ambient air into the burner. It handles cold, clean air. A 18.55 kW FD fan is very large for a standard burner; it's more likely an ID fan or a primary/secondary air fan for a stoker or biomass boiler.
Typical Performance Parameters (Estimated for 18.55 kW)
For a fan of this power on a carbon steel boiler, you would typically expect:
| Parameter | Estimated Value | Unit | Notes |
|---|---|---|---|
| Motor Power | 55 kW (25 HP) | kW | Fixed by your query. |
| Airflow (Volume) | 15,000 – 25,000 m³/h (8,800 – 14,700 CFM) | m³/h | Depends on system pressure. Higher pressure = lower flow. |
| Total Pressure | 2,000 – 5,000 Pa (8 – 20 in Wg) | Pa | ID fans often have lower pressure (2-3 kPa). High-efficiency burners might need 4-5 kPa. |
| Motorspeed | 1,450 or 2,900 RPM | RPM | 4-Pole (1450) is quieter and more common for large fans. 2-Pole (2900) is smaller but noisier. |
| Temperature (ID) | 150°C – 250°C | °C | The fan must withstand this. Look for a "Y" type water-cooled bearing housing. |
| Impeller Type | Backward Inclined (BI) or Radial Tip | - | BI is most common for efficiency. Radial Tip is used for harsh, dusty gases. |
Key Considerations for Sourcing or Replacement
If you are buying this fan, do not just rely on the power (kW). You must match the fan's performance curve to your boiler's system resistance curve.
Check these specifications from the supplier:
- Full Load Amps (FLA): The motor plate must show 18.55 kW at the correct voltage (e.g., 415V, 3-phase).
- Fan Type: Is it Forward Curved, Backward Inclined, or Radial? For a boiler ID fan, Backward Inclined is standard. For a FD fan, Forward Curved (smaller) or Backward Inclined.
- Rotor Size (Diameter): The impeller diameter (mm) determines the fan's pressure capability.
- Flue Gas Temperature: The design temperature MUST be stated (e.g., "Max. 200°C"). For an ID fan, you often need a water-cooled bearing housing to prevent bearing failure from conducted heat.
- Mechanical Seals: Are there mechanical seals where the shaft passes through the casing to prevent gas leakage? (Crucial for ID fans in positive pressure systems).
- Damper / Inlet Vanes: For a fan this size, it likely has inlet guide vanes (IGV) or a discharge damper for airflow control.
- Housing Split: For ease of maintenance, a horizontally split housing is preferred.
Common OEM / Manufacturers for such a fan
If you are looking for a replacement, these brands are typical for industrial boilers in this power range:
- Howden / New York Blower (High-quality, expensive)
- Greenheck (Commercial/Industrial)
- Chicago Blower (Industrial)
- Cincinnati Fan
- Anemoi / Pelonis (More affordable options)
- Many Chinese OEMs (e.g., for Y5-47, Y6-41 series fans - these are standard Chinese market models for 18.5 kW boiler ID fans).
Summary: What you need to buy
You need a Carbon Steel Boiler ID (or FD) Centrifugal Fan, 18.55 kW, 3-Phase.
Critical question: Is it for Forced Draft (cold air at burner) or Induced Draft (hot flue gas at stack)? If you are unsure, assume Induced Draft (ID) because that is the more common application for a 18.55 kW fan on a boiler. An 18.55 kW FD fan is enormous for a standard burner.
Buying Checklist:
- Power: 18.55 kW ✓
- Voltage: [Your local voltage, e.g., 400V/3ph/50Hz or 460V/3ph/60Hz]
- Flow: [m³/h or CFM]
- Pressure: [Pa or in Wg]
- Temp: [°C]
- Impeller: Backward Inclined
- Bearing: Water-cooled for ID fan
Recommendation: Provide your boiler manufacturer and model number to the fan supplier. They can then provide the exact fan curve to match your system. Do not buy a fan solely by kW.
