LWPI-Φ107X762-01 Cross-Flow Fan Impeller for HVAC OEM

Customer Requirement

An HVAC OEM requested a direct replacement part for their existing commercial HVAC product lines. The customer provided images of an impeller and the detailed specifications. To match their existing motor configuration, the cross-flow fan impeller is 762 mm in length and has a 107mm diameter. They required an 8 mm shaft bore with a machined flat to accept an M4X6.5 set screw. The airflow of 1000 to 1500 CFM is needed.

The OEM stipulated stringent dynamic and acoustic requirements. At speeds up to 1600 RPM, the impeller had to operate without abnormal sound. This was supported by tight manufacturing tolerances: radial runout less than 0.7 mm, axial runout less than 0.6 mm, and a remaining unbalance of 0.3g or less at 1200 RPM.

Engineering Solution

Simply copying the old impeller was not an option. The LONGWELL engineering team first specified the cross-flow impeller material. Acrylonitrile-Styrene with 30% Glass Fiber provides superior tensile strength and dimensional stability and is the suitable choice.

LONGWELL uses a modular construction approach. It is because creating a single-piece injection mold will bring a higher initial investment cost. The impeller is built from smaller, identical blade segments that are precision-joined. This strategy added the benefit of manufacturing flexibility for future length variants. The model is named LWPI-Φ107X762-01.

Technical Specifications

The final approved specifications for the LWPI-Φ107X762-01 cross-flow impeller are detailed below. All parameters are drawn directly from the final engineering drawing.

Parameter	Value	Notes
Longwell Model	LWPI-Φ107X762-01	Plastic Cross-Flow Impeller
Impeller Diameter	107 mm	–
Impeller Length	762 ± 2 mm	–
Material	AS+GF30%	Acrylonitrile Styrene with 30% Glass Fiber
Rotation	CCW	Counter-Clockwise (viewed from shaft end)
Color	Blue	–
Airflow Target	1000 – 1500 CFM	Reference only; depends on system integration
Max Operational Speed	1600 RPM	Tested for no abnormal sound at this speed
Dynamic Balance	≤ 0.3g @ 1200 RPM	Ensures low-vibration operation
Radial Runout	< 0.7 mm	Critical tolerance for OEM assembly
Axial Runout	< 0.6 mm	Critical tolerance for OEM assembly
Shaft Runout	< 0.2 mm	Defined for the steel shaft end

The extremely tight tolerances on runout and the specific dynamic balance requirement are the most critical specifications for an OEM. They guarantee that the impeller can be integrated into a high-volume production line with confidence, minimizing system vibration and ensuring a long operational life for the end product.

Technical Documentation

The customer-provided sample used for initial reverse engineering and requirement definition, highlighting the need for a precise drop-in replacement.

LWPI-Φ107X762-01 Engineering Drawing (.pdf)
This is the final approved engineering drawing, providing all dimensional, material, and tolerance data required by a design engineer for system integration.

Why LONGWELL for HVAC Impeller Replacement?

• System-Level Engineering: The LONGWELL model prioritizes system-level performance. The LWPI-Φ107X762-01 model is engineered with ultra-tight tolerance standards, ensuring the impeller aligns perfectly with the mechanical demands of HVAC systems
• Tailored OEM Customization: The LWPI-Φ107X762-01 model is a tailored cross-flow fan impeller. LONGWELL allows adjustments to impeller dimensions, blade geometry, airflow volume, mounting methods, voltage specifications, and other parameters.
• Ultra-Quiet Performance: The LWPI-Φ107X762-01 model will not produce abnormal noise at speeds up to 1600RPM. LONGWELL ultra-silent cross-flow fan series can reach as low as 18 dBA, suitable for noise-sensitive residential and commercial environments.
• Localized Service Support: LONGWELL has set up service outlets in many regions around the world, providing localized responsive technical support and after-sales service.

This project demonstrates our capability in custom component manufacturing. Explore our full Cross-Flow Fans range.

Frequently Asked Questions

Q: Can LONGWELL produce this impeller in a different material for higher temperature or chemical resistance?

A: Yes, LONGWELL can provide customized materials to meet the requirements. In the LWPI-Φ107X762-01 model, AS+GF30% was optimal for cost and rigidity needs. We can adapt designs for different operating environments.

Q: What is the typical lead time for a custom impeller like the LWPI-Φ107X762-01?

A: The minimum order quantity for a new custom impeller is typically between 100 and 500 units. LONGWELL’s NPI process, from spec lock to production release, is completed within 90 days.

Technical Documentation & Resources

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Project Item: 7026742113
Project Date: 2026-06-24 08:53:36