What are OD threads?

OD threads refer to external threads, which are threads that are located on the outer surface of a cylindrical object, such as a bolt or a screw. These threads are designed to allow the component to be mated with a corresponding internal threaded part, such as a nut or a tapped hole.

External threads are crucial for creating a secure fastening system because they enable the assembly of different components without the need for additional parts. They provide a mechanism for transferring loads and ensuring that the components stay together under various conditions.

In contrast, internal threads are located inside a hole or socket and are used for receiving external threaded components. Straight threads are characterized by having a uniform diameter throughout their length, while tapered threads gradually decrease in diameter, often used for sealing applications. The distinction of OD threads as external is fundamental in understanding how threaded fasteners are designed and utilized in mechanical applications.