Types of Machine Pins – Guide to Pin Fasteners & Industrial Pins | CNCLATHING


Machine pins come in varying configurations and commonly found in numerous applications. Pin fasteners act as other fastening devices in some cases, such as assemble two components, but their specialty set industrial pins apart from other hardware. In this article, we talk about the types of pins, and focus on the characteristics and uses of different machine pins.

What are Machine Pins?

Machine pins are a type of hardware and fastener for fastening objects or material together, the machine pins are available in semi-permanent and quick-release forms, the former one requires extra pressure or special tools for assembly and disassembly, the quick-release pins have a spring-loaded mechanism that locks these pins into place and the installation and removal become easy. Pins can be made from steel, copper, brass, wood, plastic, and more materials. No matter you want lightweight, malleable, electrically conductive aluminum pins, or cheap, corrosion-resistant plastic pins, or industrial pins made of other materials, CNC machining services at Junying can provide the best product for you. 

Types of Pins - Different Kinds of Machine Pins

1. Cotter pins: cotter pins are wired form fasteners often used in machine assembly applications and act as a locking mechanism to hold pins or nuts in place, The British definition of “cotter pin” is equivalent to the U.S. term “cotter”. Further use of the term “cotter pin” is the “crank cotter pin” used to lock bicycle pedal cranks to the bottom bracket axle. Cotter pins can be divided into circle cotter pins, extended cotter pin, hairpin cotter pin, and ring cotter pin, these different types of cotter pins vary much in shapes. 


2. Dowel pins: straight, cylindrical solid pins with different designs at the ends, including taper, slot, spiral, step, groove, etc., which classifies dowel pins into lots of categories. 

Dowel pins are mainly used to help insert and align before using other fasteners. Some of the types of dowels are drive pins (have an interference fit and must be driven into place, usually used in rotary applications), grooved pins (with longitudinal grooves which provides greater surface area for adhesive and improved power), and knurled pins (with the knurled surface which offers better grip). 


3. Spring pins: also known as roll pin or tension pin, have a body diameter that is larger than the hole diameter, and a chamfer on either one or both ends to facilitate starting the pin into the hole. Spring pins are considered as a kind of dowel pins available in coiled and rolled models. Coil spring pins are coiled into a cylindrical shape, and rolled spring pins are rolled into shape. Spring pins used to secure the position of two or more parts of a machine relative to each other. 


4. Hitch pins: commonly used to secure vehicle trailers and agricultural settings, hitch pins facilitate removal and replacement. Large hitch pin sizes are used on vehicles to secure a trailer ball mount to a receiver hitch. 


5. Linch pins: also be referred to lynch pins, similar to hitch pins, specifically designed to retain a wheel or other rotating device on its axle, but can be used as a fastener as well. Both hitch pins and lynch pins are quick-release, cylindrical, and straight pins, they are commonly found on vehicle trailers and require mating holes or other forms of a lock to be effective. These devices are meant to resist shear forces, which make them fundamentally different than bolts and screws.


6. Locating pins: designed to align or fix two workpieces to very small tolerances. Locating pins can ensure an accurate alignment when translation mechanisms are not stable precise enough to keep objects in position for a particular process. Locating pins are a great solution to make sure the parts you are putting together fit the way you want them to fit. Locating pins are available in different designs and configurations, such as varying head and shank styles. Usually, two locating pins are enough to properly locate the workpiece on one plane.