Aerospace bolts are designed to meet strict guidelines implemented by the Aerospace Industries Association and Army-Navy.
This includes requirements regarding manufacturing, finishing, tolerances, strength, and material type.
Despite this, there are a number of different types of bolts and military fasteners, which can make it quite overwhelming when purchasing.
In this post, we will explain the difference between NAS versus AN bolts so that you can get a better understanding.
What are NAS bolts?
NAS bolts comply with the National Aerospace Standards Committee’s standards. These standards are updated regularly, with revisions made to make sure that NAS parts provide reliability and high-level performance.
What are AN bolts?
AN bolts are industrial aircraft bolts that are made in accordance with the Air Force-Navy specifications. They are manufactured from zinc-plated or cadmium corrosion-resistant steel, anodized aluminum alloys, and unplated corrosion-resistant steel.
These aircraft bolts can be utilized for both shear and/or ductile applications, and are coded to a certain standard.
What are the requirements for NAS bolts?
NAS bolts contain fine threads, they come in coarse threads as well, however, the tolerance is tighter than standard bolts and are manufactured to create a very tight hold. Every bolt has recessed or raised markings that detail the materials utilized in its fabrication, for example, graded steel alloys, A286 stainless steel, and 300 series stainless steel.
Other types of NAS and AN high-performance aircraft hardware
Not only do you have a typical bolt for aircraft, but there are specialist aerospace bolts, such as close tolerance bolts for high-performance applications.
You also have many other types of fasteners that are needed for high-performance applications and must comply with the National Aerospace Standard that is in place. Let’s take a look at some in more detail:
- Cap screws – You can get standard and hex screws from numerous metals, from zinc coatings to corrosion-resistant steel. Unlike a standard bolt, cap screws tighten from the head of the bolt itself, rather than using a nut to fasten and tighten the assembly.
- Rivets – A rivet is a permanent fastener that pinches aligned mechanical pieces or plates together in a secure hold. Multiple rivets at set points around a perimeter will lower the risk of misalignment or rotation.
- Nuts – There are many types of nuts you can purchase at a hardware store, from standard nuts to anchor nuts, castle nuts, self-locking nuts, and much more. Nuts will fasten across the threaded shafts of bolts, and there are many different types available that meet the various NAS requirements for their intended applications and materials.
Purchasing AN and NAS bolts that meet National Aerospace Standards (NAS)
So there you have it: an insight into NAS bolts, which are designed to the National Aerospace Standard, and AN aerospace bolts, which are created to Air Force-Navy specs.
When purchasing aircraft hardware for the military and other defense industries, it is imperative to choose your supplier of commercial bolts with a huge amount of care. You can never afford to cut corners.