18-8 Stainless Steel 900 Series AN Flat Washers
What are 18-8 stainless 900 series AN flat washers? 18-8 stainless steel 900 series AN flat washers are precision washers made to the 900-series range of Air Force-Navy Aeronautical Standards from corrosion-resistant 18-8 stainless. Used under hex and castle nuts for a smooth bearing surface, grip-length shimming, and cotter pin alignment, they meet aircraft spec requirements where an AN part number is called out.
Why 18-8 stainless for AN washers?
18-8 stainless gives these AN washers strong corrosion and oxidation resistance, which suits airframe and aircraft hardware exposed to weather, altitude, and moisture. In tension joints, a stainless or steel washer is often specified over softer materials. Beyond the material, the 900-series AN standard defines the smooth bearing surface, thickness, and finish these washers need to shim grip length and align castle nuts reliably. Where a drawing calls for a 900 series AN part number, use the certified stainless AN washer rather than a commercial substitute, with full certifications for traceability.
Why choose 18-8 stainless 900 series AN flat washers
- Aeronautical standard: manufactured to 900-series Air Force-Navy AN specifications.
- Corrosion resistant: 18-8 stainless resists rust and oxidation.
- Grip adjustment: used as shims and to set castle nut position.
- Certified: called out by AN part number for conformance.
Common applications for 18-8 900 series AN flat washers
- Aircraft and airframe assemblies
- Shimming for correct bolt grip length
- Castle nut and cotter pin alignment
- Corrosion-exposed aircraft connections
For related standards, see NAS aerospace flat washers, and browse every option on the main flat washers category.
18-8 Stainless 900 Series AN Flat Washers FAQ
What does AN stand for?
Air Force-Navy Aeronautical Standard, a family of standards for aircraft hardware. AN960, in the 900 series, is the most widely used AN flat washer.
Why 18-8 stainless for aircraft washers?
18-8 stainless resists corrosion and oxidation, which suits airframe hardware exposed to weather, altitude, and moisture, and is often specified for tension joints.
What are 900 series AN washers used for?
A smooth bearing surface under nuts, shims to set correct bolt grip length, and adjusting castle nut position so cotter pin holes align.