Centrifugal Fans

Centrifugal fans build pressure by accelerating air outward through a rotating impeller, making them the workhorse for HVAC air handlers, cleanrooms, dust collection and process ventilation. Articles under this tag cover working principles, backward vs forward curved impellers, performance-curve reading, selection math and maintenance practice, with LONGWELL AC/DC/EC centrifugal fan data for reference.

LONGWELL centrifugal fan
By longwell / August 11, 2026 / Technical Articles

Centrifugal HVAC Fans: Complete Ordering Guide

Centrifugal fans are widely used in AHUs, ventilation equipment, and H...

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longwell centrifugal blower
By longwell / August 11, 2026 / Engineering Case Studies

LWDD7-5-C-EC-002 Centrifugal Blower for Air Filtration Systems

A 220V variable-speed EC centrifugal blower pushing 1980 m³/h at 317 P...

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Two 250mm centrifugal fans built for different fan static pressure duties
By longwell / August 3, 2026 / Engineering Case Studies

750 Pascals and 220 Pascals Are Different Fans

Same diameter, same voltage, same enclosure. The two fans share everyt...

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FCU blower on a fan overspeed test rig at 2200 RPM
By longwell / August 3, 2026 / Engineering Case Studies

Run It at 2200 RPM for Eight Hours Before You Trust It

The blowers will never see 2200 RPM in service. The customer required ...

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LWFE3G200-102SS-02-00
By longwell / July 27, 2026 / Engineering Case Studies

LWFE3G200-102SS-02-00 EC Centrifugal Fan for HVAC

An OEM required a 200mm EC centrifugal fan delivering 700 m³/h at 1000...

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Forward-curved blower housing from low-volume tooling, 150 units a year
By longwell / July 27, 2026 / Engineering Case Studies

A Custom Stamping Die for 150 Fans a Year

Tooling economics usually assume volume. This customer commissioned a ...

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LWBA for AHU cases
By longwell / July 25, 2026 / Engineering Case Studies

380V AC Centrifugal Fan for AHUs: 695 Pa High-Pressure

Developing a standardized 380V AC backward curved centrifugal fan for ...

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LONGWELL cross flow fan
By longwell / July 24, 2026 / Technical Articles

What is a Cross Flow Fan?

A cross flow fan is a type of blower designed to provide a wide and un...

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LONGWELL factory
By longwell / July 22, 2026 / Technical Articles

Centrifugal Fan OEM: What to Ask Your Manufacturer?

When you are deciding which centrifugal fan to use in the systems, you...

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Forward-curved centrifugal blower after an EC motor retrofit
By longwell / July 21, 2026 / Engineering Case Studies

Keep the Scroll, Change the Motor

The aerodynamics already worked. Everything difficult about this proje...

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