Small But Mighty - Choosing the Correct Fasteners for Your Aircraft
Chances are, you have probably used a fastener or a machine with fasteners in it within the past week. Used to make a connection between two components, fasteners are small pieces of hardware that come in very handy in a lot of different circumstances. The aerospace industry is particularly fond of fasteners as they form a rigid but temporary connection.
Unlike everyday circumstances, fasteners used in the aerospace industry are put through harsh conditions. Aircraft fly at high altitudes and are subject to vast pressure and temperature differences. The integrity of an aircraft is reliant upon the correct functioning of the fasteners. As the plane mechanisms heat up during system pre-heat, the various metals expand and contract, which in turn changes the physical relationships between metal components. This is where the question of material of the fastener comes into play.
Corrosion and pressure are the two worst enemies of a fasteners. Aluminum is a popular material within the aerospace industry because it is relatively light for a metal. The problem with aluminum is that it doesn’t stand up to the task of fastener. Aluminum rivets can be used; however, they must be cold heat formed. While they may look the part, the fasteners are highly sensitive to temperatures above 250 degrees Fahrenheit. In terms of corrosion, aluminum doesn’t fair too well either.
Steel and steel alloys are aluminum’s stronger, heavier sibling. In aerospace applications, stainless steel is a popular choice of fastener material. The series of stainless steel is very important. Series 300 corrosion resistant stainless steel avoids the risk of corrosion but does not stand up too well against the excessive heat, in an aircraft’s landing gear for example. On the other hand, CRES series 400 steels have impressive heat resistance, but is subject to corrosion. The type and use of the aircraft will help determine which material to use. While they may not be a perfect material, steel fasteners are still an integral part of an aircraft.
When it comes to the ultimate material for fasteners, superalloys are the answers. For example, H-11 is a chromium tool steel alloy which is often used in the high stress areas of an aircraft such as the landing gears.
Regardless of the type of fastener you choose, there are strict guidelines in place that ensure the correct manufacturing of the fastener. The American Society of Mechanical Engineers (ASME) created a uniform manufacturing standard. Fasteners must be the same shape, material, and composition. If you are looking for fasteners within the military, you should also be aware of military standards and parts of military standard. Traceability is particularly important to the military. If a fastener is not up to military standard, it needs to be traced back to the manufacturer and the exact manufacturing line.
At ASAP AM Spares, owned and operated by ASAP Semiconductor, we can help you find all the unique fasteners from top manufacturers such as Arconic and Eaton, for the aerospace, civil aviation, and defense industries. We’re always available and ready to help you find all the parts and equipment you need, 24/7-365. For a quick and competitive quote, email us at email@example.com or call us at +1-702-919-1616.