What Is Castellated Nut?

Pile of different nuts

Nuts are a common type of fastener. As you may know, they are used in conjunction with a bolt. Bolts are often inserted through a given object, after which they are affixed with a nut. The presence of a nut helps to secure the object by preventing the bolt from loosening or otherwise coming out. There are different types of nuts, however, one of which being castellated. What is a castellated nut exactly?

Overview of Castellated Nuts

Also known as a castle nut, a castellated nut is a type of nut that features a perimeter of raised notches on the top. It’s known as a castellated nu because it resembles a castle. The raised notches look like those of a castle. They are still used with a bolt (or screw), and they are still designed to prevent the respective fastener from loosening or otherwise coming out. Castellated nuts simply feature raised notches on top that resemble those of a castle.

How Castellated Nuts Work

Castellated nuts are distinguished from other types of nuts by their use of a pin. In addition to a bolt, they require the use of a pin. After tightening a castellated nut onto the end of a bolt, a pin is inserted through the center. The pin will essentially hold the castellated nut in place. It will run through the center of the nut and the center of the bolt to which the nut is attached.

Castellated nuts must be used with a special type of bolt. Traditional bolts, of course, are solid. Therefore, pins can pass through them. Fortunately, there are bolts available that feature a radial hole. With a radial hole, they can be used with a castellated nut. They contain a small hole in the middle through which you can run the pin.

Tips on Choosing Castellated Nuts

When choosing castellated nuts, you should consider the material from which they are made. Castellated nuts are available in many of the same materials as traditional nuts. There are carbon castellated nuts that are exceptionally strong and durable, and there are stainless steel castellated nuts that are weaker but better protected against corrosion.

You should choose castellated nuts in the right size as well. A castellated nut must feature the appropriate size for the bolt with which it’s used. If it’s too big or too small, you won’t be able to secure it to the bolt.