Dowel pins are used as industrial fasteners for many different products in aerospace, military, construction and other industrial applications. Their main use is to fasten two components together but they are also commonly used as alignment or locating pins in products that are frequently unassembled and reassembled. Dowel pins also have other uses such as hinge pins and as axels for products that have an element that needs to rotate.
Parallel Dowel Pins
Parallel dowel pins are the most common type of dowel pins. Parallel dowel pins are also referred to as straight pins. They are called straight pins because the diameter is the same for the entire length of the dowel pin. These pins are usually found in applications where torque and pinpoint accuracy are critical components of the assembled parts. They allow for smooth operation of parts and keep assembled parts together.
Tapered Dowel Pins
Tapered dowel pins are generally referred to as taper pins because they have a diameter that gets smaller from one end to the other end. The larger end is called the head and the smaller end is called the point. A taper pin will be forcefully inserted into a hole that also tapers. This makes for an extremely strong connection between two parts.
Roll pins are parallel pins that are created by forming strips of flat metal in a partial coil. From the end, this type of pin will resemble the letter “C”. Roll pins are made in a variety of diameters and lengths that can be used for many applications. The main advantage that a roll pin will offer is that when it is forced into a hole that is intentionally undersized the pin will compress and then hold position with tremendous force.
A Spring Post pin is a parallel dowel pin that has a groove around the circumference of the pin on one end. The pin is inserted into the hole with the end of the groove intentionally left exposed. Then the groove is utilized to attach an expansion spring. This enhances the holding power of the pin.
Grooved dowel pins are parallel dowel pins that have grooves that run the length of the pin. For some applications, the grooves may only run part of the length of the pin. These pins are also known as groove pins. The purpose of this type of pin is that it can be press-fitted into one component while allowing another component to rotate freely on the smooth portion of the pin.
- Photo Credit plastic dowel image by Aleksandr Ugorenkov from Fotolia.com