Description
Centrifugal Fan
Stable airflow and dependable pressure for industrial ventilation and air-exchange systems. Two model families — LWFDF4-79A direct drive and LWFDF4-2X79E belt drive — cover 990 to 52,960 m³/h behind a thickened carbon steel casing and a balanced backward-curved impeller.
Key Features at a Glance
Two model families, 29 catalogue codes and one airflow platform — built for ventilation duty that runs all shift.
Product Specifications
Performance data and installation dimensions for both families. LWFDF4-79A is direct drive (sizes 3A to 6A); LWFDF4-2X79E is belt drive (sizes 4A to 8A).
| Model | Speed (r/min) | Matching Motor (kW·p) | Flow Rate (m³/h) | Total Pressure (Pa) |
|---|---|---|---|---|
| LWFDF4-79A-3A-1.5-2P-1-001 | 2900 | 1.5-2 | 1970-3830 | 1196-726 |
| LWFDF4-79A-3A-0.75-4P-1-002 | 1450 | 0.75-4 | 990-1910 | 304-177 |
| LWFDF4-79A-3.5A-3-2P-1-001 | 2900 | 3.0-2 | 3120-6070 | 1628-981 |
| LWFDF4-79A-3.5A-1.1-4P-1-002 | 1450 | 1.1-4 | 1560-3040 | 412-245 |
| LWFDF4-79A-4A-5.5-2P-1-001 | 2900 | 5.5-2 | 4670-9080 | 2138-1275 |
| LWFDF4-79A-4A-1.1-4P-1-002 | 1450 | 1.1-4 | 2330-4540 | 530-324 |
| LWFDF4-79A-4.5A-11-2P-1-001 | 2900 | 11-2 | 6640-12920 | 2697-1618 |
| LWFDF4-79A-4.5A-1.5-4P-1-002 | 1450 | 1.5-4 | 3320-6450 | 677-402 |
| LWFDF4-79A-5A-15-2P-1-001 | 2900 | 15-2 | 9100-17720 | 3334-2001 |
| LWFDF4-79A-5A-2.2-4P-1-002 | 1450 | 2.2-4 | 4560-8860 | 834-500 |
| LWFDF4-79A-6A-5.5-2P-1-001 | 1450 | 5.5-2 | 7890-15320 | 1196-706 |
| LWFDF4-79A-6A-1.5-6P-1-002 | 960 | 1.5-6 | 5230-10100 | 530-314 |
| Model | Speed (r/min) | Matching Motor (kW·p) | Flow Rate (m³/h) | Total Pressure (Pa) |
|---|---|---|---|---|
| LWFDF4-2X79E-4A-5.5-4P-1-001 | 2250 | 5.5-4 | 6790-11390 | 1350-864 |
| LWFDF4-2X79E-4A-3-4P-1-002 | 1800 | 3.0-4 | 5400-9110 | 864-553 |
| LWFDF4-2X79E-4A-1.5-4P-1-003 | 1350 | 1.5-4 | 4080-6840 | 486-311 |
| LWFDF4-2X79E-5A-11-4P-1-001 | 2000 | 11-4 | 13600-18820 | 1640-1230 |
| LWFDF4-2X79E-5A-5.5-4P-1-002 | 1550 | 5.5-4 | 7980-13340 | 1010-647 |
| LWFDF4-2X79E-5A-2.2-4P-1-003 | 1200 | 2.2-4 | 6380-11640 | 618-412 |
| LWFDF4-2X79E-6A-18.5-4P-1-001 | 1800 | 18.5-4 | 16760-29820 | 1996-1362 |
| LWFDF4-2X79E-6A-5.5-4P-1-002 | 1200 | 5.5-4 | 10990-20070 | 882-588 |
| LWFDF4-2X79E-6A-2.2-4P-1-003 | 800 | 2.2-4 | 7360-13380 | 392-265 |
| LWFDF4-2X79E-7A-30-4P-1-001 | 1600 | 30-4 | 24930-48330 | 1971-1167 |
| LWFDF4-2X79E-7A-15-4P-1-002 | 1250 | 15-4 | 19470-37710 | 1206-716 |
| LWFDF4-2X79E-7A-7.5-4P-1-003 | 1000 | 7.5-4 | 15570-30240 | 775-461 |
| LWFDF4-2X79E-7A-3-4P-1-004 | 710 | 3.0-4 | 10990-21420 | 392-235 |
| LWFDF4-2X79E-8A-30-4P-1-001 | 1270 | 30-4 | 23760-52960 | 1569-932 |
| LWFDF4-2X79E-8A-15-4P-1-002 | 1000 | 15-4 | 21520-41680 | 971-578 |
| LWFDF4-2X79E-8A-7.5-4P-1-003 | 800 | 7.5-4 | 17210-33360 | 618-373 |
| LWFDF4-2X79E-8A-3-6P-1-004 | 600 | 3.0-6 | 13520-26320 | 387-225 |
| Model | Motor Power | Φ1 | Φ2 | Φ3 | A1 | A2 | A3 | a×x | B1 | B2 | B3 | b×y | n1-d1 | C1 | C2 | C3 | C4 | C5 | E | E1 | H | H1 | H2 | H3 | L | L1 | n3-d3 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| LWFDF4-79A-3A | 1.5-2 | 300 | 335 | 365 | 234 | 266 | 294 | 3×88.6 | 325 | 357 | 387 | 4×89.3 | 14-Φ8 | 280 | 310 | 420 | 30 | 480 | 524 | 234 | 400 | 645 | 171 | 245 | 526 | 121 | 4-Φ10 |
| LWFDF4-79A-3A | 0.75-4 | 300 | 335 | 365 | 234 | 266 | 294 | 3×88.6 | 325 | 357 | 387 | 4×89.3 | 14-Φ8 | 205 | 235 | 380 | 30 | 440 | 524 | 234 | 400 | 645 | 171 | 245 | 516 | 121 | 4-Φ10 |
| LWFDF4-79A-3.5A | 3-2 | 350 | 388 | 416 | 273 | 305 | 333 | 3×101.6 | 375 | 407 | 435 | 4×101.8 | 14-Φ8 | 290 | 330 | 445 | 40 | 525 | 612 | 273 | 460 | 746 | 202 | 286 | 630 | 142 | 4-Φ10 |
| LWFDF4-79A-3.5A | 1.1-4 | 350 | 388 | 416 | 273 | 305 | 333 | 3×101.6 | 375 | 407 | 435 | 4×101.8 | 14-Φ8 | 290 | 330 | 445 | 40 | 525 | 612 | 273 | 460 | 746 | 202 | 286 | 565 | 142 | 4-Φ10 |
| LWFDF4-79A-4A | 5.5-2 | 410 | 440 | 462 | 310 | 342 | 370 | 4×85.5 | 428 | 460 | 488 | 4×115 | 16-Φ8 | 366 | 416 | 540 | 50 | 640 | 700 | 312 | 520 | 878 | 229 | 328 | 742 | 162 | 4-Φ14 |
| LWFDF4-79A-4A | 1.1-4 | 410 | 440 | 462 | 310 | 342 | 370 | 4×85.5 | 428 | 460 | 488 | 4×115 | 16-Φ8 | 235 | 275 | 485 | 40 | 565 | 700 | 312 | 520 | 878 | 229 | 328 | 607 | 162 | 4-Φ14 |
| LWFDF4-79A-4.5A | 11-2 | 450 | 490 | 512 | 349 | 381 | 409 | 4×95.3 | 477 | 509 | 537 | 5×101.8 | 18-Φ8 | 400 | 450 | 710 | 50 | 810 | 786 | 351 | 620 | 987 | 259 | 367 | 882 | 181 | 4-Φ14 |
| LWFDF4-79A-4.5A | 1.5-4 | 450 | 490 | 512 | 349 | 381 | 409 | 4×95.3 | 477 | 509 | 537 | 5×101.8 | 18-Φ8 | 245 | 295 | 510 | 50 | 610 | 786 | 351 | 590 | 957 | 259 | 367 | 677 | 181 | 4-Φ14 |
| LWFDF4-79A-5A | 15-2 | 500 | 550 | 572 | 390 | 422 | 450 | 4×105.5 | 530 | 562 | 590 | 5×112.4 | 16-Φ8 | 400 | 450 | 750 | 50 | 850 | 871 | 390 | 660 | 1066 | 288 | 406 | 922 | 225 | 4-Φ14 |
| LWFDF4-79A-5A | 2.2-4 | 500 | 550 | 572 | 390 | 422 | 450 | 4×105.5 | 530 | 562 | 590 | 5×112.4 | 16-Φ8 | 265 | 315 | 560 | 50 | 660 | 800 | 390 | 660 | 1066 | 288 | 406 | 747 | 225 | 4-Φ14 |
| LWFDF4-79A-6A | 5.5-4 | 600 | 645 | 676 | 466 | 498 | 526 | 5×99.6 | 645 | 677 | 705 | 6×112.8 | 22-Φ8 | 366 | 416 | 705 | 50 | 805 | 1046 | 470 | 760 | 1246 | 338 | 486 | 913 | 241 | 4-Φ14 |
| LWFDF4-79A-6A | 1.5-6 | 600 | 645 | 676 | 466 | 498 | 526 | 5×99.6 | 645 | 677 | 705 | 6×112.8 | 22-Φ8 | 295 | 345 | 660 | 50 | 760 | 1046 | 470 | 760 | 1246 | 338 | 486 | 838 | 241 | 4-Φ14 |
High Airflow & Stable Pressure
The optimized centrifugal airflow structure delivers steady air volume and dependable pressure, helping support efficient ventilation, air exchange and process exhaust.
Between them the two families cover 990 to 52,960 m³/h and 177 to 3,334 Pa. The direct-drive LWFDF4-79A sizes handle the middle of that range — up to 17,720 m³/h on the 5A-15-2P — while the belt-drive LWFDF4-2X79E sizes run on up to 52,960 m³/h on the 8A-30-4P. Because the volute and impeller are sized for each other rather than for the motor, the fan still holds its working pressure at the far end of a long duct run.
- Wide coverage — LWFDF4-79A: 990 to 17,720 m³/h; LWFDF4-2X79E: 4,080 to 52,960 m³/h
- Dependable pressure — total pressure from 177 Pa up to 3,334 Pa across 29 catalogue codes
- Directed discharge — the rectangular outlet keeps air moving through long duct runs and multi-branch systems
Low Vibration & Stable Operation
The statically and dynamically balanced impeller, together with the stable fan structure, helps reduce operational vibration and maintain smooth, reliable performance during continuous use.
Vibration is usually what ends a fan's service life first: it works fasteners loose, wears bearings and eventually cracks welds. Here the impeller is balanced as a set with its shaft, and the casing, bearing bracket and base are welded into one stiff frame, so the running load is carried by structure rather than passed back into the motor. Speeds are matched to the duty point instead of always running flat out — 2,900 r/min where airflow demand is highest, 600 to 960 r/min on the slow-running 6-pole models.
- Balanced rotating assembly — impeller and shaft balanced before assembly, so less vibration reaches the bearings
- Stiff welded frame — casing, bearing bracket and base behave as one structure
- Speed matched to duty — 600 to 2,900 r/min across the series, not one speed for everything
Reliable Motor for Continuous Operation
The motor is selected according to the fan model and operating requirements, providing dependable power for continuous ventilation, air exchange and air-conveying applications.
Matching motor power runs from 0.75 kW on the LWFDF4-79A-3A four-pole unit up to 30 kW on the LWFDF4-2X79E 7A and 8A. Two-pole motors at 2,900 r/min are used where the airflow demand is highest, four-pole motors cover most general duty points between 800 and 2,250 r/min, and six-pole motors at 600 to 960 r/min are used where noise and bearing wear matter more than peak output. On the belt-drive 2X79E sizes the pulley ratio can be changed on site, so a duty point that shifts later does not mean a new fan.
- Matched ratings — 0.75 kW to 30 kW across the two families
- 2, 4 and 6-pole options — speed chosen for the flow, pressure and noise target
- Re-tunable on belt drive — adjust the transmission ratio rather than replace the fan
Backward-Curved Impeller for Stable Airflow
The backward-curved impeller is designed for smooth and stable airflow delivery. Dynamically and statically balanced, it helps maintain reliable operation with good aerodynamic performance.
Because the blades lean away from the direction of rotation, air leaves the wheel gradually instead of being thrown off the tips. That keeps the pressure curve flatter as system resistance rises, which is what stops the airflow from collapsing when filters load up or a damper is adjusted. The wheel runs on a supported shaft with the bearing bracket mounted outside the casing, so the bearings are not sitting in the dust, moisture or fumes being handled.
- Backward-curved blades — smooth airflow delivery with a flatter pressure curve
- Balanced as a set — static and dynamic balancing before the impeller goes on the shaft
- Bearings clear of the air stream — easier lubrication and longer service intervals
Thickened Carbon Steel Casing
The fan has a thickened carbon steel casing with a quality electrostatic powder coating. The reinforced structure resists wear and corrosion, reduces vibration, and eases installation and commissioning.
The volute and side plates are rolled and welded from thickened steel, so the casing keeps its profile under continuous static pressure instead of flexing and drumming.
Applied after welding, the coating covers the welds and cut edges that normally start to rust first.
Suited to workshops where dust, moisture and fumes are present every working day.
A one-piece base with drilled feet and flanged inlet and outlet, so the unit bolts down and connects without extra fabrication.
Two Families, One Airflow Platform
Pick the family first: the direct-drive LWFDF4-79A covers the middle of the range, the belt-drive LWFDF4-2X79E covers the top end. Both use the same casing, impeller and bearing arrangement.
Sizes 3A to 6A — 990 to 17,720 m³/h
Six sizes running at 960, 1,450 and 2,900 r/min, with matching motors from 0.75 kW to 15 kW and total pressure from 177 Pa to 3,334 Pa. The motor mounts on the fan itself, so the unit stays compact and there is no belt to tension or replace.
Sizes 4A to 8A — 4,080 to 52,960 m³/h
Five sizes running at 600 to 2,250 r/min, with matching motors from 1.5 kW to 30 kW and total pressure from 225 Pa to 1,996 Pa. The pulley ratio sets fan speed, so the duty point can be trimmed on site and the motor can be placed where there is space and service access.
Two Drive Configurations for Different Installation Needs
Select a suitable configuration according to the installation space, duct direction, equipment layout and maintenance requirements.
Compact Structure, Space-Saving Installation
The motor mounts on the fan shaft, so there is no belt to tension or replace and the footprint stays small — useful inside packaged units, plant rooms and machine-side air-exchange systems. Simple drive configuration, easy system integration. LWFDF4-79A, sizes 3A to 6A.
Separate Motor Arrangement, Flexible Installation
The motor sits on its own base and drives the fan through V-belts, so it can be placed where there is room, the outlet can be turned to suit the duct run, and the transmission ratio can be adjusted when the duty point changes. Suitable for industrial ventilation systems. LWFDF4-2X79E, sizes 4A to 8A.
Wide Industrial Applications
Covers a wide range of industrial and commercial ventilation scenarios — from everyday air exchange to mining and centralized ventilation projects.
Factory Workshops
Supply and exhaust air for production halls and assembly shops working through long shifts.
Industrial Buildings
Air exchange for large industrial buildings with long duct runs and high working areas.
Warehouses
Air movement and heat removal in warehouses, storage halls and logistics facilities.
Hotels & Commercial Buildings
Ventilation, air exchange and exhaust for hotels, kitchens and commercial premises.
Mining Ventilation Systems
Air supply and exhaust for mine galleries, shafts, tunnels and underground workings.
Equipment Air-Exchange Systems
Cooling and air exchange for production equipment, drying lines and process machines.
General Exhaust Systems
Everyday extraction of stale air, heat, dust and odour from working spaces.
Centralized Ventilation Projects
Central fan stations serving multi-branch duct networks across a whole plant.
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 LWFDF4-79A / 4-2X79E fan arrives ready to install.
Global Market & Client Preference
The LWFDF4-79A / 4-2X79E series is specified by HVAC distributors, equipment manufacturers and OEM clients across Europe, the Middle East, Southeast Asia and South America.
Trusted by Leading Global HVAC Brands
24+ HVAC OEMs and equipment builders rely on LONGWELL for industrial centrifugal fans every year.
Complete Range of Professional & Certified
LONGWELL fans are independently certified to international quality, safety and energy-efficiency standards.
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View Product →Frequently Asked Questions
Quick technical answers about the LWFDF4-79A / 4-2X79E centrifugal fan series.
What is the LWFDF4-79A/4-2X79E centrifugal fan used for?
The series is used for industrial ventilation and air exchange — factory workshops, industrial buildings, warehouses and logistics facilities, hotels and commercial buildings, mining ventilation, equipment air-exchange systems, general exhaust systems and centralized ventilation projects.
What is the difference between the LWFDF4-79A and the LWFDF4-2X79E?
The LWFDF4-79A is the direct drive family, sizes 3A to 6A, running at 960, 1,450 and 2,900 r/min with air volumes from 990 to 17,720 m³/h. The LWFDF4-2X79E is the belt drive family, sizes 4A to 8A, running at 600 to 2,250 r/min with air volumes up to 52,960 m³/h; fan speed is set by the pulley ratio, so it can be matched more closely to the required duty point.
What air volume and total pressure can this series reach?
Air volume ranges from 990 m³/h on the LWFDF4-79A-3A-0.75-4P up to 52,960 m³/h on the LWFDF4-2X79E-8A-30-4P. Total pressure ranges from 177 Pa up to 3,334 Pa on the LWFDF4-79A-5A-15-2P.
What motor and speed options are available?
Matching motor power runs from 0.75 kW to 30 kW. 2-pole motors run at 2,900 r/min for the highest airflow points, 4-pole motors cover most general duty points at 800 to 2,250 r/min, and 6-pole motors at 600 to 960 r/min are used where lower noise and lower wear matter more than peak output.
Which drive configuration should I choose?
Direct drive (LWFDF4-79A) mounts the motor on the fan, giving a compact unit with no belt to tension or replace — suitable where space is tight. Belt drive (LWFDF4-2X79E) puts the motor on a separate base, so it can be positioned where there is room, the outlet can be turned to suit the duct run, and the transmission ratio can be adjusted on site if the duty point changes.
Does LONGWELL offer OEM or custom options for this series?
Yes. LONGWELL provides OEM/ODM support including custom casing and flange dimensions, mounting base changes, motor and voltage matching, special surface treatment for corrosive or dusty duty, and private label branding.
Need a Quote or Custom Specs?
Send us the air volume, total pressure and installation layout. Our engineers will match the right LWFDF4-79A or LWFDF4-2X79E model — drive type, motor and dimensions — and reply within 24 hours.
