I.D. Fans
I.D. FANS- An Induced Draft Fan creates negative pressure (vacuum) inside a boiler or furnace by drawing flue gases through the system. This ensures efficient combustion and safe removal of exhaust gases.
Key Components
| Component | Description |
| Impeller | Backward-curved or radial blades for high pressure rise |
| Casing | Spiral (scroll) housing; may be insulated for heat control |
| Inlet Guide Vanes | Control airflow and improve efficiency |
| Drive System | Belt-driven or direct-coupled motors; VFDs for speed control |
| Bearings | Grease or oil-lubricated bearings for high-speed operation |
| Silencer (optional) | Reduces noise generated by air intake |
Design Parameters
| Parameter | Typical Range / Notes |
| Flow rate (Q) | 5,000 – 100,000+ m³/h |
| Static pressure (ΔP) | 500 –1000 Pa |
| Air temperature | Ambient to 120°C (usually preheated via air preheater) |
| Efficiency | 65% – 85% |
| Fan type | Centrifugal (most common), axial for high-volume low-pressure systems |
| Material | Mild steel or stainless steel (for corrosion resistance) |
F.D. Fans
Function
A Forced Draft (FD) Fan supplies pressurized ambient air into the combustion chamber. It provides the oxygen needed for combustion and helps maintain a positive pressure inside the furnace or boiler.
Main Role: Push fresh air into the combustion system through burners or grates.
Key Components
| Component | Description |
| Impeller | Backward-curved or radial blades for high pressure rise |
| Casing | Spiral (scroll) housing; may be insulated for heat control |
| Inlet Guide Vanes | Control airflow and improve efficiency |
| Drive System | Belt-driven or direct-coupled motors; VFDs for speed control |
| Bearings | Grease or oil-lubricated bearings for high-speed operation |
| Silencer (optional) | Reduces noise generated by air intake |
Design Parameters
| Parameter | Typical Range / Notes |
| Flow rate (Q) | 5,000 – 100,000+ m³/h |
| Static pressure (ΔP) | 500 –1000 Pa |
| Air temperature | Ambient to 120°C (usually preheated via air preheater) |
| Efficiency | 65% – 85% |
| Fan type | Centrifugal (most common), axial for high-volume low-pressure systems |
| Material | Mild steel or stainless steel (for corrosion resistance) |