Centrifugal Utility Set – CUS

Volume Capacity: 500~56,000 m³/h (294~32,941CFM)

Static Pressure: 136~1,400 Pa (0.55~5.62 in.WG.)

Drive Type: Belt/ Direct drive

Installation Methods: Base Mount/ Ceiling Hanging

Applications: Industrial ventilation / Explosion proof air exhaust / Kitchen fume exhaust


Outstanding Characteristics of the 4th Generation of Wind-Surfer wheel

— It has great sound and air performance

— The wheel boasts high efficiency and wide range of performance without overload

— Its balancing level reaches G2.5 (Just G6.3 for ordinary products)

Aerodynamic Design

— The CFD simulation technology is used for optimized design which is also validated through repeated trials.

— The wheel cone and inlet cone are designed in line with flow field characteristics.

— Airflow through flow passages is well controlled.

— The blade pitches are optimized.

Optimized Design for Structure

— FEA method is used to analyze stress and improve performance.

–Different product models are specified with different strengthening structures to make products more reliable.

— Structural stress is prevented through using the riveting technology.

Updated Wheel

— The CUS wheel is upgraded to the 4th generation.

–Its overall performance is 5-10% greater over the 3rd generation.

–Its overall sound is 2-3 dB(A) less than the 3rd generation.

High-standard Processes

— Excellent air performance is achieved as the wheel cone and inlet cone are both formed through the spinning process.

— By using the inlet cone, smooth airflow can be produced.

— Formed through the punching process, blades have a reliable quality standard.

— Special fixtures and other tools are applied so that blades are mounted at the right positions.


Wide Range of Performance

— The range of wheel diameter is 300~ 1,000 mm.

— More choices are offered in model selection rendered by wide ranges of RPM and performance

— Range of performance can be adjusted through adjusting the pulley turns and replacing the motor.

Scroll Turned for Different Discharge Options on the Site

8 equally distributed bolts fix the scroll. Within the allowable range, discharge directions can be adjusted on the site.

AMCA Spark Resistant Constructions

— Supply Spark A and Spark B construction options in line with AMCA99-10

— Spark A: The housing is constructed of aluminum. The wheel and inlet cone are constructed of aluminum

— Spark B: The Wheel and inlet cone are constructed of aluminum

Continuously Welded Housing

— The housing is continuously welded and thus has great strength.

— In moist air ventilation, the housing can perform better than the scroll manufactured with lock seam.

— Leakage will not happen inside the scroll as a result of the dropping liquid.

— With the housing, the fan can be well used for ventilating air that has condensed water and kitchen fumes.

Convenient Maintenance

— There are access doors on two sides of the motor.

— Electrical parts can be inspected and maintained using just one screw driver.

— Scroll access door is included in the package of standard accessories.

Suitable for Installation Outdoors 

— The rain cover can be chosen to offer protection of the drive parts.

— Total protection of driving parts is provided from sun, rain and snow.

— The adverse effects of climate on fan service life and safe operation are reduced.

Compact Structure

— For belt drive, AMCA arrangement 10 is used (The motor is right under the shaft); for direct drive, AMCA arrangement 4 is used.

— Space is reduced for installation.

— Shorter belt is required and its service life is prolonged.

— The scroll center height is lower. The air ducts have more installation space.

AMCA Seal for Sound and Air Performance

— CUS fans have won the AMCA Seal for Sound and Air Performance.

— CUS fans are labeled with AMCA Seal for Sound and Air Performance.


CUS fans have the AMCA certification for Sound & Air Performance & FEG and are CE certified.

Quality Standards

Tests shall be performed on the SWSI centrifugal fans and certificates obtained under AMCA Standard 210 & 300. Each fan shall bear the AMCA Seal for Sound and Air Performance before leaving the factory. The manufacturer shall get the ISO9001:2000certification.

Fan Type

The CUS fan shall have an aluminum backward inclined centrifugal wheel. The driving types include direct and belt drive type. To ensure the fan has smooth air movement, the wheel cone shall be designed with a curved section. Each wheel shall undergo static and dynamic balancing tests and reach AMCA 204- G2.5 balancing level (Standard ISO 1940).

Housing Material

Constructed of steel, the housing shall have enough thickness and strength to support the drive unit and motor. The processes of alkaline wash and parkerizing shall be conducted on the fan surface treated with electrostatic epoxy coatings. Colors are customizable.

Drive Unit (For belt drive type only)

Shaft: Heat treated through soaking furnace, the shaft shall reach a hardness level of HB370. Hard film treatment shall be made on the surface to avoid corrosion. The shaft and the wheel shall be dynamically balanced together. It shall have its speed designed at least 25% more than the highest running speed of the fan.

Pulleys: The size of the pulleys shall be at least 150% of the driving power. Pulleys shall be made of cast iron and available for on-site adjustment. For the purpose of easily removing the pulleys, conical type bushings shall be used.

Bearings: The shaft shall be supported by two bearings so that vibrations can be offset. The bearing shall have a minimum L10 life of 80, 000 hours at the maximum cataloged speed. It shall be permanently sealed type and metal pillow block ball bearing that can be lubricated.

Drive Support: Thick powder-coated and anti-corrosive steel sheet shall be used to support the drive unit. By adjusting the bolt at the motor base, the belt tension shall be available for adjustment. The fan shaft and motor shaft shall be made parallel.

Guards: For belt drive CUS fans, a shaft/bearing guard and belt guard shall be included in the package of standard accessories. When used for outdoor installation, a rain cover shall be mounted for total protection of the motor and other driving parts to ensure their service life.


There shall be a close match between the motor and the fan load. The motor shall have a degree of protection standard IP54 and an insulation class F. Its bearing shall be of ball type and require no lubrication. To avoid grease or dirt accumulation, the motor and drive unit shall be located out of the airstream.


AMCA Type B spark resistant construction shall be included for the CUS fan. Aluminum shall be used on the wheel and inlet. There shall be an access door for the scroll so that the unwanted bodies that stay inside the fan can be easily removed. The fan shall be placed on a flat surface and vibration isolators are used.

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