Description
Boiler Used Introduced Draft Fan
Boiler Induced Draft | Flue Gas Extraction | Belt Drive. Engineered for intense extraction against severe system resistance.
Product Specifications
Complete performance parameters for the LWIDF9-19 and 9-26 series.
Currently, there are many kinds of boilers with different coal characteristics. The addition of dust removing devices and waste heat recovery equipment increases system resistance, which can make the draft power insufficient for normal operation. To overcome the lack of draft power, positive pressure, and to ensure the normal inflammation of the boiler, we design and manufacture varieties of Boiler Induced Draft Fans with suitable flow rates and pressures to fit different requirements.
The main parameters of the Boiler Induced Draft Fan are flow rate, total pressure, main shaft rotation speed, inner power and inner efficiency, etc. The parameters of the Induced Draft Fan are based on a gas temperature of 200°C.
| Model | Speed (r/min) | Total Pressure (Pa) | Flow Rate (m³/h) | Matching Boiler Capacity (t/h) | Matching Motor (kW-p) |
|---|---|---|---|---|---|
| LWIDF9-19-4.5A-1.1-4P-1-001 | 2000 | 1439-1365 | 1146-1739 | 0.2 | Y90S-4 (1.1) |
| LWIDF9-19-4.5A-2.2-4P-1-002 | 2150 | 1668-1629 | 2511-3222 | 0.5 | Y100L1-4 (2.2) |
| LWIDF9-19-6.3A-4-4P-1-001 | 1870 | 2491-2364 | 2912-4419 | 1 | Y112M-4 (4) |
| LWIDF9-19-6.3A-5.5-4P-1-002 | 1900 | 2572-2440 | 3940-5979 | 1 | Y132S-4 (5.5) |
| LWIDF9-19-8A-7.5-4P-1-001 | 1450 | 2394-2334 | 5113-7235 | 2 | Y132M-4 (7.5) |
| LWIDF9-19-8A-11-4P-1-002 | 1620 | 2986-2913 | 5712-8083 | 2 | Y160M-4 (11) |
| LWIDF9-19-8.4A-7.5-4P-1-001 | 1330 | 2331-2273 | 6452-9130 | 2 | Y132M-4 (7.5) |
| LWIDF9-26-6.3A-7.5-4P-1-001 | 1870 | 2473-2415 | 5994-7689 | 2 | Y132M-4 (7.5) |
| LWIDF9-26-8A-18.5-4P-1-001 | 1620 | 3516-2969 | 10699-16075 | 4 | Y180M-4 (18.5) |
| LWIDF9-26-8A-22-4P-1-002 | 1710 | 3516-3308 | 11293-16968 | 4 | Y180L-4 (22) |
| LWIDF9-26-8.5A-18.5-4P-1-001 | 1450 | 2854-2685 | 11486-17258 | 4 | Y180M-4 (18.5) |
Thickened Carbon Steel Casing
Fine craftsmanship and a spray-painted finish provide a durable surface with good wear resistance, while the reinforced structure supports reliable long-term operation.
Extracting boiler flue gas at 200°C exposes the fan to aggressive thermal and chemical stress. Fabricated entirely from heavy-gauge carbon steel plates, the LWIDF9-19 casing resists structural warping. The industrial-grade exterior coating further defends the metal against rust and particulate abrasion.
- Spray-Painted Finish — protects against industrial corrosion and humid atmospheres
- Reinforced Casing — rigid plates withstand immense internal pressure and heat
- Durable Enclosure — resists abrasion from passing fly ash and soot
Dependable Draft for Boiler Exhaust
Changes in fuel characteristics and exhaust system configuration can increase draft requirements. Selecting a suitable fan helps address insufficient draft and supports effective flue gas extraction.
Creating a stable vacuum is essential for efficient combustion. This introduced draft fan overcomes aerodynamic resistance from long flues and particulate filters, forcibly pulling the hot exhaust out. Its targeted aerodynamic curve prevents flame instability in 0.2 to 4 t/h industrial boiler setups.
- Boiler Exhaust — safely evacuates searing fumes from the facility
- Dependable Draft — stabilizes combustion across different firing rates
- Flue Gas Extraction — prevents dangerous exhaust backflow
Draft Support for Higher System Resistance
Dust collectors, waste heat recovery equipment and ductwork add resistance to the exhaust system. Select the fan by the required airflow and total pressure to suit the complete system.
While standard exhaust fans struggle with complex ducting, the LWIDF9-19 generates up to 3,516 Pa of static lift. This moderate-pressure, high-flow characteristic is perfectly balanced to overcome aerodynamic drag from baghouses and scrubbers without unnecessarily overworking the motor.
- Dust Collection — pulls exhaust through dense particulate filters effortlessly
- Heat Recovery — forces hot gas through restrictive heat exchangers
- Ductwork — prevents gas from stalling in long factory pipelines
Centrifugal Design for Boiler Draft
The centrifugal fan draws gas through the inlet and discharges it through the casing outlet, providing the airflow and pressure needed to move flue gas through the exhaust system.
Precision-balanced to eliminate vibration during continuous 200°C operation. The aerodynamic blade design aggressively pulls dense, hot flue gases from the combustion chamber, preventing dangerous exhaust backflow and maintaining steady furnace efficiency.
- Centrifugal Design — rapidly extracts high-temperature smoke and ash
- Boiler Draft — maintains required negative pressure in the furnace
- High-Heat Resistance — built to process 200°C flue gas continuously
Reliable Motor for Boiler Draft
The motor is matched to the fan's operating requirements and delivers power through the belt drive, supporting dependable flue gas extraction.
To survive the grueling ambient heat of industrial boiler rooms, these fans are driven by premium industrial motors. Ranging from 1.1 kW to 22 kW, these powerplants offer superior thermal stability, ensuring the fan runs continuously on S1 duty cycles without overheating or losing torque.
- Matched Motor — calibrated strictly against the required extraction load
- Reliable Power — maintains consistent RPM against fluctuating draft conditions
- Continuous Duty — rated for non-stop industrial boiler room environments
Belt Drive with an External Motor
The external motor drives the fan through a belt and pulley system. Confirm the drive configuration, operating speed and installation space when selecting the unit.
This belt-driven arrangement provides essential flexibility in motor positioning and transmission ratio selection. More importantly, it physically isolates the motor from the 200°C volute casing, preventing heat transfer that could damage electrical windings during continuous boiler operations.
- External Motor — isolated from the intense heat of the extracted flue gas
- Belt Drive — allows engineers to fine-tune extraction speeds via pulleys
- Installation Planning — adaptable to specific spatial constraints in boiler rooms
Built for Boiler Exhaust Systems
Engineered to extract hot flue gas and overcome severe system resistance in industrial boiler networks.
Industrial Boilers
Extracts combustion gases efficiently from 0.2-4 t/h systems to sustain stable thermal output.
Boiler Rooms
Maintains negative furnace pressure to guarantee consistent heat generation and safe operation.
Dust Collection Systems
Overcomes severe aerodynamic drag in baghouses and scrubbers to capture airborne ash effectively.
Waste Heat Recovery
Pulls hot exhaust gases through restrictive heat exchangers to reclaim energy without stalling the system.
Flue Gas Exhaust
Generates intense vacuum pressure to safely evacuate hazardous, high-temperature smoke from the facility.
Steam Boiler Systems
Delivers the critical draft required to maintain rapid water heating and consistent steam pressure.
LONGWELL — Trusted Industrial Fan Manufacturer Since 1990
Founded in 1990 in Yuyao, Ningbo — the heart of China’s advanced manufacturing belt — LONGWELL has grown from a precision fan component workshop into a vertically integrated ventilation technology group. Today we engineer AC, DC and EC fan and motor systems with 4,000 m²+ of manufacturing floor, dedicated aerodynamics and CFD simulation labs, and a global export network spanning Europe, the Americas and Asia-Pacific.
From material selection to final balancing, every LONGWELL fan is built on automated lines, computer-balanced impellers and 100% run-test before shipment. We are certified to ISO 9001:2015 and ISO 14001, with CE, UL/ETL, RoHS and EAC compliance, and performance tested to the AMCA 210/211 method.
Production & Delivery
Automated lines, computer-balanced impellers and a 100% run-test on every unit, so each LWIDF9-19 fan arrives ready to install.
Global HVAC&R Exhibitions Participation
Meeting boiler manufacturers, project contractors, and OEM engineering teams at international trade fairs worldwide.
Trusted by Leading Global OEM Brands
24+ equipment builders rely on LONGWELL for industrial centrifugal blowers every year.
Complete Range of Professional & Certified
LONGWELL fans are independently certified to international quality, safety and energy-efficiency standards.
Global Market & Client Preference
The LWIDF9-19 and 9-26 series are specified by boiler manufacturers and industrial clients across Europe, the Middle East, Southeast Asia and the Americas.
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View Product →Frequently Asked Questions
Quick technical answers about the LWIDF9-19 / 9-26 boiler introduced draft fan.
What is the primary function of the LWIDF9-19/9-26 fan?
It is an introduced draft fan engineered specifically to extract flue gases from industrial boiler systems, ensuring proper negative pressure is maintained within the combustion chamber for safe and stable operation.
Can this fan handle high-resistance exhaust systems?
Yes, it is purposefully designed for higher system resistance. It generates sufficient static pressure (up to 3,516 Pa) to pull exhaust through restrictive dust collectors, ductwork, and waste heat recovery equipment without stalling.
What boiler capacities is this series matched to?
The performance parameters of this series are carefully matched for small to mid-sized industrial boilers, specifically accommodating steam outputs ranging from 0.2 to 4 tons per hour (t/h).
Why does this fan use a belt drive with an external motor?
The external motor configuration isolates sensitive electrical components from the extreme heat of the flue gas passing through the volute. The belt drive also provides flexibility in selecting transmission ratios to precisely match the required fan speed.
Need a Quote or Custom Specs?
Send us the air volume, total pressure, and installation layout. Our engineers will match the right LWIDF9-19 or 9-26 model and reply within 24 hours.
