Bolts are commonly used in the construction of airplanes and other types of aircraft. Consisting of a threaded shank and an integrated head, they are used to fasten two or more parts. Bolts, however, are available in different styles, such as reduced head.
What Are Reduced Head Bolts?
Also known as low-profile bolts, reduced head bolts are threaded fasteners with a lower or shorter head than traditional bolts. They still have a shank, which is either partially or fully threaded. The head of a reduced head bolt is simply shorter than that of a traditional bolt.
The photo above depicts a typical reduced head bolt. The threads extend about halfway up the shank, with the remainder of the shank being smooth and unthreaded. At the top of the shank is the head. The head, of course, sits lower because it’s a reduced head bolt. Traditional bolts have a similar design consisting of a threaded shank and a head, but the head on a traditional bolt is taller and protrudes farther out from the shank.
Why Use Reduced Head Bolts
With their low-sitting head, reduced head bolts offer several advantages over traditional bolts. The head, for instance, will lie flush with the parts with the parts they are used to fasten. It won’t stick out of the surface of the parts. Rather, the head on a reduced head bolt will lie flush.
There may not be enough space for a tall, protruding head. In aerospace manufacturing applications, space is often limited. This makes reduced head bolts an excellent choice for such applications. Even if there’s not enough room for a traditional bolt, a reduced head bolt may work because the head will lie flush with the respective part.
Reduced head bolts offer aesthetic benefits as well. They feature a sleek, modern appearance that many people prefer. Traditional bolts, in comparison, are larger and bulkier due to their tall, protruding heads.
What to Look for in a Reduced Head Bolt
You should consider the material when choosing a reduced head bolt. Like with other types of bolts, they are typically made of metal. But the specific type of metal or alloy from which a reduced head bolt is made may vary. Some of them are made of stainless steel or carbon steel, whereas, other reduced head bolts are made of cadmium-plated steel.
Reduced head bolts are available in different sizes. You’ll need to choose a size that’s appropriate for your intended fastening application. Make sure the reduced head bolt is the right length and width, and that it has the right thread size. Otherwise, it may not work.
