Nas523 Rivet Code Pdf May 2026

NAS523 Rivet Code is a standardized symbolic system used in aviation engineering drawings to provide precise instructions for fastener installation. It uses a single "crosshair" symbol divided into four quadrants, each representing specific rivet data. Quadrant Breakdown

Information is placed in the following "compass" positions relative to the center cross: NW (Northwest - Upper Left): Contains a two-letter code representing the head style and alloy " identifies a standard MS20470AD rivet (2117 alloy). NE (Northeast - Upper Right): Indicates the rivet diameter " increments) and the location of the manufacturer's head " stands for Near Side; " " stands for Far Side. SW (Southwest - Lower Left): hole preparation or special methods. ": Dimpled. ": Countersunk. ": Dimple the top two sheets and countersink the third. SE (Southeast - Lower Right): Specifies the fastener length " increments. " rivet is shown as " Resources & PDF Guides

Detailed NAS523 documentation and identification charts can be found on several technical hosting platforms: NAS523 Rivet Identification Guide (Scribd)

: A comprehensive breakdown of head markings, alloy letters, and the NAS523 symbol system. Installation of Basic Aircraft Fasteners (Blue Tuna Docs)

: Provides technical diagrams showing the "cross" symbol and its variations. NAS523 - Fastener Code (GlobalSpec)

: Official standard practice documentation for permanent deformation fasteners. specific alloy code list (e.g., what "BJ" or "CX" stands for) or a guide on how to calculate proper rivet length for your specific sheet metal thickness? NAS523 Rivet Identification Guide | PDF - Scribd

3. Interpreting the Part Number Hierarchy

The NAS523 standard helps you break down the confusing string of letters and numbers found on a blueprint. Here is the logic you would find in the document:

Example Part Number: MS20470AD4-5

MS20470: The Head Style. (In this case, a Universal Head / Protruding Head).
- Interesting Note: If this were MS20426, it would be a Countersunk (Flat) Head.
AD: The Material Code. (2117-T4 Aluminum, no refrigeration needed).
4: The Diameter Code. The formula in the PDF tells you to multiply this by 1/32nd of an inch.
- $4 \times \frac132 = \frac432 = \frac18$ inch diameter.
5: The Length Code. The formula usually dictates multiplying by 1/16th of an inch.
- $5 \times \frac116 = \frac516$ inch length.

Deep Article: NAS523 Rivet Code (PDF)

Conclusion

The NAS523 rivet code is more than just a numbering system—it is the language of aerospace structural integrity. Whether you are a mechanic looking to replace a fastener or an engineer designing a spar, understanding how to decipher the codes (and having the NAS523 PDF handy for verification) is a non-negotiable skill. nas523 rivet code pdf

Keep a copy of the standard in your toolbox or digital workspace, and you’ll never be left guessing about a fastener again.

Disclaimer: This blog post is for educational purposes. Always consult the official NAS523 standard document and your specific Aircraft Maintenance Manual (AMM) or Structural Repair Manual (SRM) for certified data.

The NAS523 rivet code is a standardized symbolic system used on aviation engineering drawings to specify exact rivet types, dimensions, and installation requirements. Instead of listing details in text, a "crosshair" symbol is used, with each of the four quadrants (named like a compass) containing specific information: Quadrant Breakdown

NW (Northwest - Upper Left): Specifies the rivet part number (e.g., AN or MS standards) and the material/alloy code. For example, the code "BJ" might identify a universal-head rivet made of 2117-T3 aluminum.

NE (Northeast - Upper Right): Indicates the rivet diameter (in 1/32" increments) and the manufactured head location. The letters N (Near) or F (Far) tell the technician which side of the sheet the head should be placed on.

SW (Southwest - Lower Left): Provides dimpling or countersinking instructions, showing exactly what type of prep work is required for the installation.

SE (Southeast - Lower Right): Specifies the fastener length in 1/16" increments. For instance, a value of "-6" would indicate a length of 3/8" (6/16"). Common Reference PDFs

You can find detailed charts and full specifications in these documents: NAS523 Rivet Code is a standardized symbolic system

NAS523 Rivet Identification Guide (Scribd): A comprehensive guide often used in A&P technician training.

Aircraft Standard Hand Book: Contains practical instructions on marking holes and removing skins using the NAS523 system.

NASA Fastener Design Manual: Offers high-level engineering data on fastener materials, strengths, and design criteria. NAS523 Rivet Identification Guide | PDF - Scribd

The NAS523 Rivet Code is a standardized symbol used in aviation diagrams and engineering drawings to specify precise details for fastener installation. Instead of long text strings, it uses a single four-quadrant "crosshair" symbol to communicate the rivet part number, material, size, and necessary hole preparation. Quadrant Breakdown

The system organizes information into four specific quadrants designated by compass directions:

NW (Northwest - Upper Left): Contains the rivet identity, typically a two-letter code representing the part number (AN or MS) and the material/alloy.

Example: BJ identifies a standard MS20470AD (universal head) rivet made from 2117 aluminum alloy.

NE (Northeast - Upper Right): Specifies the rivet diameter in MS20470: The Head Style

-inch increments and the location of the manufacturer's head (indicated as "Near" or "Far").

SW (Southwest - Lower Left): Details special methods or hole preparation required, such as dimpling (D) or countersinking (C). D2: Dimple both sheets. D2C: Dimple two top sheets and countersink the third. SE (Southeast - Lower Right): Specifies the rivet length in -inch increments. Example: A -6negative 6 code indicates a -inch length. Key Specifications & Reference

For a complete list of material codes and head styles, technicians typically refer to the full NAS-523 Standard PDF or specialized guides like those found on Scribd and Studylib. Unit of Measurement Example Code Diameter Length Hole Prep D (Dimple), C (Countersink)

NAS523 Rivet Code is a symbolic identification system used in aviation diagrams and engineering drawings to communicate fastener specifications clearly through a four-quadrant "crosshair" symbol. NAS523 Quadrant Breakdown

The code provides details for each quadrant without explicitly labeling the compass designations (NW, NE, SW, SE). Northwest (Upper Left) : Specifies the Part Number (e.g., AN or MS) and Material/Alloy The letters represent an MS20470AD rivet made from 2117 aluminum alloy. Northeast (Upper Right) : Specifies the Rivet Diameter and the required location of the manufactured head. : Manufactured head is on the : Manufactured head is on the Southwest (Lower Left) : Provides Dimple and Countersink instructions. means dimple the top two sheets and countersink the third. Southeast (Lower Right) : Indicates the Rivet Length , often shown in increments like -6. Reference Documents

For full technical specifications and a complete listing of letter codes, you can consult these resources: NAS523 Rivet Identification Guide : A detailed 4-page guide is available via Scribd (NAS523 Guide) Fastener Design Manual : While more general, the NASA Technical Reports Server provides extensive data on rivet selection and strength. Aircraft Standard Handbook : Chapter 10 of this Aircraft Standard Handbook covers marking holes according to NAS523 codes. material code (like BJ, BB, or AD) to identify a particular rivet? NAS523 Rivet Identification Guide | PDF - Scribd

code is a symbolic system used on aviation blueprints and technical drawings to specify rivet installation details within a single four-quadrant "crosshair" symbol. NAS523 Quadrant Breakdown

The information is organized into four quadrants representing different technical specifications: NW (Northwest / Upper Left): Specifies the rivet part number (typically MS or AN) and the material alloy code The letters identify an MS20470AD rivet made of 2117 aluminum alloy. NE (Northeast / Upper Right): Indicates the rivet diameter

" increments and the required positioning of the manufactured head. : Manufactured head on the : Manufactured head on the SW (Southwest / Lower Left): Details the hole preparation method required, such as dimpling or countersinking. : Countersink. : Dimple top two sheets, countersink the third. SE (Southeast / Lower Right): Specifies the rivet length " increments. negative 6 code indicates a " rivet length. Reference Documents

Comprehensive details and code charts are typically found in manufacturer-specific manuals or standard practice documents: NAS523 Rivet Identification Guide (PDF) AIA/NAS Standard Practice NAS523 Aircraft Solid Shank Rivet ID Guide (like BJ, BH, or BB) or a full conversion chart for a particular aircraft model? NAS523 Rivet Identification Guide | PDF - Scribd