On April 20, 2026, LONGWELL opened a project to provide mounting hardware for fan assembly applications. The customer requested carbon steel hardware sets consisting of three components: M6x20 hex socket head cap screws, flat washers, and spring washers, with a requested volume of 5,000 pieces per component.
Technical specifications and hardware design
LONGWELL engineering defined the standard specification under part number designation M6x20. Technical specification documentation completed on April 23, 2026, established the dimensional requirements, thread pitch, and surface treatment for the three-piece carbon steel assembly.
| Component | Parameter | Specified Dimension / Standard |
|---|---|---|
| Hex Socket Screw | Thread Size (d) | M6-1 |
| Hex Socket Screw | Thread Length (L) | 19.6 – 20.4 mm |
| Hex Socket Screw | Head Diameter (dk) | 9.78 – 10.0 mm |
| Hex Socket Screw | Head Height (k) | 5.7 – 6.0 mm |
| Hex Socket Screw | Hex Socket Width (s) | 5.02 – 5.14 mm |
| Hex Socket Screw | Hex Socket Depth (t) | Min 3.0 mm |
| Flat Washer | Outer Diameter (dw) | 11.57 – 12.0 mm |
| Flat Washer | Thickness (h3) | 1.52 – 1.68 mm |
| Spring Washer | Thickness (S) | 1.5 – 1.7 mm |
| Assembly Set | Material & Surface Treatment | Steel, blackening treatment, grade 12.9 |
Technical outcome and deliverable
The technical evaluation delivered a standardized specification drawing for the M6x20 carbon steel screw, flat washer, and spring washer hardware set, providing confirmed geometry and surface finish details for customer integration and fit verification.
Discuss a similar requirement
If you require custom or standard fan mounting hardware, contact our engineering team with your structural mounting requirements and mechanical material preferences. You can submit details through our contact page or explore fan options via the LONGWELL Fan Selection Tool.
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