: Designates a specific material and head combination (often referencing MS20470 AD rivets depending on the specific company process standard cross-reference chart). -4 : Indicates a diameter of 4/32 inch (1/8"). -3 : Indicates a length of 3/16 inch. The NAS523 Rivet Symbol on Blueprints
The NAS523 code system offers several advantages for aerospace design and manufacturing:
: Exact load-bearing calculations required for structural engineering and FAA certification.
Detailed specifications and charts for these codes can be found in several technical guides: nas523 rivet code pdf
Critical Note: In the official NAS523 PDF tables, the length is measured from under the head for universal head rivets, or overall length for countersunk rivets. Always verify the grip length (material stack thickness) plus clinch allowance using the formula provided in the specification.
: Structural thresholds for each code configuration under specific environmental loads.
If the top quadrant read MS20426AD (flush shear head) and the right quadrant read C , the technician would machine-countersink the top sheet to a 100-degree angle before inserting the rivet. Why You Need a NAS523 Rivet Code PDF Reference : Designates a specific material and head combination
I can’t provide copyrighted PDFs directly. For authoritative copies:
Tip: Always ensure you are referencing the latest revision of the NAS523 PDF. Revisions can change material codes or installation tolerances, and using outdated specs can lead to structural failures.
Before NAS523, different manufacturers might have used different codes to identify similar rivets. This created chaos in the supply chain and on the maintenance hangar floor. NAS523 standardized this into a logical format that tells you everything you need to know about a fastener just by looking at its part number. The NAS523 Rivet Symbol on Blueprints The NAS523
The code might also include letters representing installation methods, such as 'D' for dimpled and 'W' for spot-welded. How to Find a NAS523 Rivet Code PDF
Aerospace engineering relies on standardization to ensure safety and structural integrity. Every fastener used in an aircraft must be precisely identified. The National Aerospace Standard defines a universal coding system for rivets [1]. This system condenses complex engineering specifications into a short, manageable string of characters.