Quality Control

Fan quality control on the line: balance grade, airflow and sound spot checks, hipot and insulation testing, and what a QC report should show you.

longwell-wi-7075113607-project
By longwell / August 17, 2026 / Engineering Case Studies

120mm Cross Flow Fan: 50,000 Unit OEM Assembly Project

Read how we engineered a custom 120mm cross flow fan assembly deliveri...

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Axial blower stator with a copper motor winding, specified explicitly
By longwell / August 10, 2026 / Engineering Case Studies

Why the Customer Wrote “100% Pure Copper” on the Order

Nobody specifies what they trust to be there. When a procurement team ...

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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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A 120mm DC fan with impedance-type locked rotor protection
By longwell / July 30, 2026 / Engineering Case Studies

If the Blades Jam, the Fan Must Not Burn: 72 Hours of Proof

Every requirement in this order assumed the fan works. One requirement...

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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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Fan filter kit adapting a 120mm axial fan to a 150mm cabinet cutout
By longwell / July 25, 2026 / Engineering Case Studies

The Cutout Is the Requirement, Not the Fan

The customer asked for a 150mm fan that barely exists. What their cabi...

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Cross-flow fan under fan quality inspection against drawing criteria
By longwell / July 10, 2026 / Engineering Case Studies

No Rust, No Burrs, No Gaps: the Drawing Said So

Most drawings specify what the fan does. This one also specified what ...

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longwell-wi-6984982400-project
By longwell / May 8, 2026 / Engineering Case Studies

Specifying 0.2g Fan Balancing Weights for Fast Impellers

See how we engineered exact 0.2g, 0.3g, and 0.4g fan balancing weights...

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longwell-wi-6985126398-project
By longwell / May 8, 2026 / Engineering Case Studies

HVAC Motor Vibration Isolator Replacement Project

See how Longwell reverse-engineered a 1,000-piece replacement motor vi...

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longwell-lwaa2d250s-5meb-31-pr
By longwell / April 23, 2026 / Engineering Case Studies

250mm Hydraulic Radiator Cooling Fan | 415V

Read how we specified a 250mm hydraulic radiator cooling fan to meet 4...

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