Air Blower Manufacturer & Supplier from China
As a centrifugal blower manufacturer, Slovdson supplies the complete range: industrial centrifugal blowers for factory ventilation, centrifugal exhaust blowers, inline centrifugal blowers, high-pressure centrifugal blowers for process air, boiler draft blowers, dust exhaust blowers, and special-application centrifugal equipment. Our centrifugal blower line covers flows from a few hundred to over 1,750,000 m³/h and pressures from 100 Pa to over 20,000 Pa. All products are CE and ISO 9001 certified.
How a Centrifugal Blower Works
The principle is straightforward, but the details determine the performance.
Air (or gas) enters the impeller eye axially. The rotating impeller blades — whether backward curved, forward curved, radial, or airfoil — grab the air and fling it outward. The air leaves the impeller at the blade tips with high velocity and enters the volute housing. The volute is a spiral-shaped casing whose cross-section expands continuously around the circumference. As the air travels through the volute, the expanding cross-section converts velocity (kinetic energy) into static pressure. By the time the air reaches the discharge flange, most of the velocity has been converted to usable pressure.
This is fundamentally different from an axial fan (which moves air in a straight line, like a desk fan) and from a positive displacement blower like a roots blower (which traps and pushes discrete volumes of air). A centrifugal blower is a kinetic machine — it adds energy to the air by accelerating it, then converts that kinetic energy to pressure in the volute. The result: high airflow volume at low-to-medium pressure, with smooth, non-pulsating output.
Centrifugal Blower Types — Choosing the Right Impeller
The impeller blade design is the single biggest factor determining a centrifugal blower's performance, efficiency, and suitability for different applications. Understanding the main centrifugal blower types helps you specify correctly.
Backward Curved (Backward Inclined) Centrifugal Blowers
Backward curved centrifugal blowers — also called backward inclined centrifugal blowers — have blades that curve away from the direction of rotation. The blade tips point "backward" relative to rotation. This is the workhorse design for industrial ventilation.
- Efficiency: Highest of all centrifugal types — 80–89% at the design point
- Pressure capability: Moderate to high
- Non-overloading: If system resistance drops, the motor won't overload — a critical safety feature in industrial environments
- Best for: General industrial ventilation, HVAC air handling, boiler draft, process air, dust collection (with appropriate blade reinforcement)
- Variants: Flat backward-inclined plates (simpler, for clean air) and curved airfoil profiles (higher efficiency, for large HVAC and power generation blowers)
Forward Curved Centrifugal Blowers
Forward curved centrifugal blowers have blades that curve in the direction of rotation. The blade tips point "forward." This design generates more pressure for a given impeller diameter and speed than backward curved — but at lower efficiency.
- Efficiency: 60–75%
- Pressure: Higher pressure per stage than backward curved at the same diameter/speed
- Compact: Smaller impeller for the same duty — fits where space is limited
- Best for: Furnace blowers, fan coil units, residential HVAC, clean-room recirculation, and any application where compact size matters more than peak efficiency
- Note: Forward curved blowers CAN overload the motor if system resistance drops below the design point. They need stable duct resistance.
Radial Blade Centrifugal Blowers
Radial blade centrifugal blowers have straight blades extending radially from the hub — no curve, no inclination. They're the simplest design and the most robust.
- Efficiency: 65–75%
- Self-cleaning: Flat radial blades don't accumulate material — ideal for particulate-laden gas
- High-speed capable: Simple geometry handles higher tip speeds than curved blades
- Best for: Dust exhaust, material conveying, high-pressure process air, and applications where the gas stream contains particulates that would clog curved blades
- Wear-resistant variants: Hard-faced blade leading edges or replaceable wear plates for abrasive service
Airfoil Centrifugal Blowers
Airfoil centrifugal blowers use hollow, wing-shaped blades — essentially backward-curved blades with an aerodynamic profile. They're the premium efficiency option.
- Efficiency: Up to 90–92% — the highest of any centrifugal blower type
- Pressure: High pressure at high efficiency
- Best for: Large HVAC systems, power plant forced/induced draft, tunnel ventilation, and any continuous-duty application where energy cost justifies the higher purchase price
- Trade-off: Airfoil blades are more expensive to manufacture and more sensitive to particulate erosion than flat backward-inclined blades
Comparison at a Glance
| Blade Type | Efficiency | Pressure | Particulate Tolerance | Best Application |
|---|---|---|---|---|
| Backward Curved / Inclined | 80–89% | Medium–High | Low–Medium | General industrial ventilation, HVAC |
| Forward Curved | 60–75% | High (for size) | Low | Compact HVAC, furnace blowers |
| Radial Blade | 65–75% | High | High | Dust exhaust, material conveying |
| Airfoil | 88–92% | High | Low | Large HVAC, power generation, continuous duty |
Our standard industrial centrifugal blowers (YX series) use backward-inclined blade impellers — the best all-around choice for general industrial ventilation. For specific applications (dust, high pressure, high temperature), we recommend the blade type that matches your operating conditions.
Centrifugal Blower Configurations — Drive, Inlet & Mounting
Beyond blade design, centrifugal blowers vary in how the impeller is driven and how the unit is installed.
Drive Types
- Direct drive (A-type). Impeller mounted directly on the motor shaft. Compact, zero belt maintenance, fixed speed. Common on smaller blowers up to ~630 mm impeller diameter and on EC/DC blowers where the motor speed is electronically controlled.
- Belt drive (C-type). Motor and blower shaft connected by V-belts and pulleys. This belt-driven centrifugal blower configuration allows speed changes by swapping pulleys. Absorbs shock loads. Requires periodic belt tension checks and replacement. The most common configuration for mid-size industrial blowers.
- Coupling drive (D-type). Motor and blower shaft connected by a flexible coupling. For large blowers (above ~200 kW) where belt drive would be impractical. Allows the motor to be mounted separately from the blower for thermal isolation in high-temperature applications.
Inlet Configurations
- Single inlet (SISW — Single Inlet Single Width). Air enters from one side of the impeller. The standard configuration for most industrial blowers.
- Double inlet (DIDW — Double Inlet Double Width). Air enters from both sides of a double-width impeller. Effectively doubles the flow capacity at a given housing size. Common in HVAC air handling units and large ventilation systems. Also searched as double inlet centrifugal blower or didw centrifugal blower.
Mounting and Installation Types
Centrifugal blowers are installed in a variety of configurations depending on the application:
- Inline centrifugal blowers (also: inline centrifugal fans, in line centrifugal fans, inline centrifugal duct fans). Cylindrical housing with the blower mounted in-line with the ductwork. Air flows straight through. Used for duct boosting, bathroom and kitchen extraction, and any installation where space is tight, and the blower must integrate into existing round or square ducting. → Our YX series can be configured for inline installation.
- Centrifugal exhaust blowers (also: centrifugal exhaust fans, centrifugal extractor fans). Designed specifically for extracting air from a space — factory ventilation, warehouse exhaust, kitchen hood extraction, bathroom extraction. Can be wall-mounted, ceiling-mounted, roof-mounted, or duct-connected. Often include backdraft dampers and weather protection for outdoor installation. → See our industrial ventilation blower series.
- Roof-mounted centrifugal exhaust blowers (also: centrifugal roof exhaust fans, centrifugal upblast exhaust fans, centrifugal downblast exhaust fans). Mounted on a roof curb or penetration. Upblast designs discharge air vertically to disperse it above the roof. Downblast designs discharge downward toward the roof for applications where vertical discharge isn't desirable. Weather-protected motor housing and bird screen are standard.
- Cabinet centrifugal blowers. The blower and motor are enclosed in a sound-insulated cabinet with duct connections on the inlet and outlet. Used in commercial buildings where noise is a concern.
How a Centrifugal Blower Compares to Other Blower Types
| Centrifugal Blower | Roots Blower | Ring Blower | |
|---|---|---|---|
| Type | Kinetic (dynamic) | Positive displacement | Kinetic (regenerative) |
| Best at | High volume at low–medium pressure | Constant flow regardless of pressure | Moderate flow at moderate pressure |
| Typical flow range | Up to 1,750,000 m³/h | Up to ~21,700 m³/h | Up to ~3,000 m³/h |
| Typical pressure | 100–20,000 Pa | 10,000–80,000 Pa | 10,000–60,000 Pa |
| Pressure characteristic | Flow drops as pressure rises | Flow stays nearly constant | Flow drops moderately |
| Noise | Moderate | Loud (75–102 dB) | Quiet (46–76 dB) |
| Oil-free | Yes (greased bearings only) | Requires oil lubrication | Yes |
You may tell the differences between a centrifugal blower, roots blower, and ring blower from the above table. If your application is ventilation, combustion air supply, flue gas extraction, fume exhaust, or process air delivery — anything that needs to move large volumes of air against mild-to-moderate resistance — a centrifugal blower is the efficient choice and a roots blower would be overkill. If your application demands constant flow as system pressure varies significantly, a roots blower may be more appropriate.
Our Centrifugal Blower Product Range
All blowers are built with welded steel plate housings, dynamically balanced impellers, and standard motors (380V / 6000V / 10000V depending on size). We offer direct-drive (A-type), belt-drive (C-type), and coupling-drive (D-type) transmissions.
Industrial Centrifugal Blowers — General Ventilation
The core of our centrifugal blower line. Industrial centrifugal blowers for factory air exchange, building ventilation, warehouse air movement, and general process air supply.
| Series | Flow Range (m³/h) | Pressure Range (Pa) | Sizes | Notes |
|---|---|---|---|---|
| YX68 | 565–657,601 | 167–6,468 | 2.8#–25# | Standard ventilation |
| YX72 | 565–657,601 | 167–6,468 | 2.8#–28# | Extended to larger sizes |
| YX90 | Similar range | Similar | — | Alternative performance envelope |
→ Browse Industrial Centrifugal Blowers — YX series, general-purpose ventilation & air handling
Centrifugal Exhaust Blowers
Dedicated centrifugal exhaust blowers (also called centrifugal exhaust fans or centrifugal extractor fans) for factory ventilation, warehouse air extraction, dust and fume removal, and process exhaust. Available in wall-mounted, roof-mounted, ceiling-mounted, and inline duct configurations. Can be specified with explosion-proof motors, corrosion-resistant construction (stainless steel or FRP), and high-temperature ratings for flue gas and kiln exhaust.
→ Contact us with your exhaust flow and pressure requirements for a specific recommendation.
High Pressure Centrifugal Blowers
High-pressure centrifugal blowers (also: high-pressure centrifugal fans) for applications where standard ventilation blowers don't develop enough pressure. Process air supply to burners, pneumatic conveying assist, air knife systems, and aeration. These are the blowers that sit at the upper end of the pressure spectrum — delivering the same kinetic efficiency but with reinforced impellers and housings designed for elevated discharge pressure.
- YX09 / YX12 / YX19 / YX26 / YX28 — High-pressure centrifugal blower series, delivering elevated pressure for process applications
Boiler Draft Blowers — Forced & Induced
For supplying combustion air to industrial boilers (forced draft) and extracting flue gas (induced draft). These centrifugal blowers handle elevated temperatures and must maintain stable performance under varying boiler load conditions.
- YX38 / YX39 / YX47 / YX48 — Boiler induced draft blowers, standard temperature
- GY series (GY0.5-15 through GY35-15) — Forced & induced draft, rated for flue gas inlet temperatures up to 200°C
- GY5-51 / GY6-51 — Combined induced draft and forced draft
- Y4-2X73(F) — Double-inlet, double-support for 300MW+ power generation units. Alloy steel shaft, forced oil lubrication, 280–2,800 kW
Dust Exhaust Blowers
For particulate-laden gas streams in dust collection systems, baghouse exhaust, cyclone exhaust, and material handling. These centrifugal blowers use reinforced radial or backward-inclined impellers designed to resist abrasive wear — the impeller blades and volute cut-off are the critical wear points, and we offer hard-facing and replaceable wear plates for extended service life.
- YXC46 / YXC48 — Dust exhaust centrifugal blower series
High-Efficiency & Special Application Blowers
- GY4-73 / YEX / YX30 — High-efficiency centrifugal blowers with optimized impeller geometry for lower energy consumption on continuous-duty applications
- YX68 Brick Kiln — Energy-saving induced draft for brick and ceramic kilns. Hardened straight-blade impeller with high-temperature anti-corrosion coating, split housing for access.
- SJ Series — Sintering blowers for steel and metallurgical processes. Up to 7,800 kW, 6000V/10000V motors. Designed for hot, dusty, corrosive sintering flue gas.
Small Centrifugal Blowers & Specialty Motors
We also supply small centrifugal blowers with AC, DC, or EC (electronically commutated) motors for compact applications — electronics cooling, equipment ventilation, medical device air handling. EC centrifugal blowers are particularly efficient for variable-speed applications. Available in 12V, 24V, and standard line voltage configurations. Contact us with your size and voltage requirements.
Customization Options
All centrifugal blower series are available with:
- Explosion-proof construction — ATEX-compatible for flammable gas or combustible dust atmospheres. Spark-resistant impeller materials (aluminum or brass) and explosion-proof-rated motors.
- Corrosion-resistant materials — Stainless steel (304/316) housing and impeller for chemical vapors and marine environments. FRP centrifugal blowers (fiberglass-reinforced plastic) available for highly corrosive applications.
- High-temperature rating — For flue gas, kiln exhaust, and drying systems up to 250°C. Motor isolation via shaft seal and heat slinger. High-temperature bearing grease.
- Wear-resistant treatment — Hard-facing weld overlay on impeller blade leading edges and volute cut-off. Replaceable wear plates for abrasive dust applications.
- Custom outlet angles — 0° to 270° in 45° increments, clockwise or counterclockwise rotation.
- Motor options — 380V, 6000V, 10000V (standard); 220V, 440V, 60 Hz, and other voltages on request. Direct drive, belt drive, or coupling drive.
Frequently Asked Questions
What are the main types of centrifugal blowers?
The main centrifugal blower types are defined by impeller blade design: backward curved (backward inclined) centrifugal blowers (highest efficiency, non-overloading, best for general industrial ventilation); forward curved centrifugal blowers (compact, higher pressure per diameter, best for HVAC and furnace blowers); radial blade centrifugal blowers (self-cleaning, handles particulates, best for dust exhaust and material conveying); and airfoil centrifugal blowers (premium efficiency up to 92%, best for large HVAC and power generation). Additionally, centrifugal blowers are classified by drive type (direct, belt, coupling), inlet configuration (single inlet SISW, double inlet DIDW), and mounting (inline, roof, wall, ceiling, cabinet).
What's the difference between a centrifugal blower and a centrifugal fan?
In practice, there is no consistent distinction — the terms centrifugal blower and centrifugal fan are used interchangeably throughout the industry. Some engineers use "fan" for lower-pressure applications (ventilation, HVAC) and "blower" for higher-pressure applications (process air, combustion air), but this is a convention, not a rule. Our product line includes both low-pressure ventilation units and high-pressure centrifugal blowers, and we use both terms to ensure we cover how our customers search.
What is an inline centrifugal blower?
An inline centrifugal blower (also called an inline centrifugal fan or in-line centrifugal fan) is a centrifugal blower housed in a cylindrical casing designed to mount directly in-line with ductwork. The air enters and exits along the same axis, with the centrifugal impeller and motor mounted inside the tube. Inline centrifugal duct fans are used for duct boosting, bathroom and kitchen extraction, and any application where the blower must integrate into existing round or square ducting without the space required by a traditional scroll-housing blower.
What is the difference between backward curved and forward curved centrifugal blowers?
Backward curved centrifugal blowers have blades that curve away from the direction of rotation. They're more efficient (80–89%), non-overloading (motor current won't spike if duct resistance drops), and are the standard for industrial ventilation. Forward curved centrifugal blowers have blades that curve in the direction of rotation. They develop more pressure for a given impeller size and speed, allowing a smaller, more compact blower — but at lower efficiency (60–75%) and with the risk of motor overload if system resistance drops below design. Forward curved blowers are common in residential HVAC, furnace blowers, and compact commercial equipment.
How do I select the right centrifugal blower for my application?
Centrifugal blower selection is driven by two primary numbers: the required airflow (m³/h or CFM) and the total pressure (Pa or inches of water) the blower must overcome. If you have these values, we can match the right series, size, impeller type, and motor within minutes. If you don't have them, describe your application — what you're moving (clean air, dust, fumes, flue gas), through what ductwork or resistance, at what temperature, and in what environment (indoors, outdoors, hazardous area). We'll calculate the requirements and recommend the right centrifugal blower.