Engineering Case Studies

Application requirements, product choices and engineering project stories from LONGWELL.

Control cabinet cooling fan sized for 824 m3/h against packed drives
By longwell / August 5, 2026 / Engineering Case Studies

A Cabinet Full of Drives Is Not Free Air

The airflow number on the datasheet assumes nothing is in the way. Ins...

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Draft inducer fan built for the flue gas of a biomass pellet boiler
By longwell / August 5, 2026 / Engineering Case Studies

The Fan That Lives in the Flue Gas

The customer did not come with a wish list. They came with a failure h...

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EC axial fan with fan tachometer output for rack RPM monitoring
By longwell / August 5, 2026 / Engineering Case Studies

The Fan That Reports Its Own Speed

Most fans are trusted rather than checked. This customer wanted the fa...

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Matched 185mm axial fans in a push-pull fan configuration
By longwell / August 4, 2026 / Engineering Case Studies

One Fan Pushes, the Other Pulls

The customer ordered the same fan twice — once sucking, once blowing. ...

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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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Dual voltage fan variants sharing one cross-flow chassis
By longwell / August 1, 2026 / Engineering Case Studies

Two Voltages, One Chassis, and No Universal Motor

The same fan had to ship into 115-volt and 230-volt markets. There are...

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Heat exchanger axial fans built as a pilot production run of fifty
By longwell / July 31, 2026 / Engineering Case Studies

Fifty Units First: What a Pilot Batch Is Actually For

The drawings were approved and the samples passed. The customer still ...

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AC axial fan qualified for vertical and horizontal fan mounting orientation
By longwell / July 30, 2026 / Engineering Case Studies

Shaft Up, Shaft Sideways: the Fan Has to Survive Both

Most specifications never mention which way the fan will point. This o...

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EC fan wiring interface with power, control and feedback leads
By longwell / July 30, 2026 / Engineering Case Studies

Eight Wires, and Every One of Them Specified

The airflow requirement took one line. The wiring specification took a...

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