Did you know that most screws are tightened in a clockwise rotation? However, even though fasteners share this similarity, they are actually all different. This is because there are several different types of screws, bolts, and fasteners available, and each one is used for its own unique purposes.
1. Square head bolts. These were actually the first bolts ever created, and they are still in use today. Created by P. L. Robertson in 1908, square head bolts can be fastened using open-end wrenches, which means they require 90 degrees of free space in order to be turned. Although this is seen as a minor inconvenience to some, square head bolts are still being used because of their versatility, durability, and availability in countless sizes.
2. Hex head bolts. These types of fasteners have six-sided heads. This not only means that they can be used with nearly any type of wrench, including adjustable wrenches, but it also means that they require less free space in order to be turned. As a result, hex head bolts are used in a variety of applications, such as machinery, furniture, and large appliances.
3. Metric plow bolts. These types of bolts are characterized by their flat heads and square necks. What makes them unique is that when they fasten two objects together, their flat heads create a smooth, seamless surface. This means that metric plow bolts are commonly used in scoop shovels, road graters, and gang plows.
While all fasteners may be similar, there are actually several notable differences between them. In addition to being shaped differently, different bolts are used for distinctively unique purposes. Fortunately, because the U.S. fastener industry generates $27 billion in annual revenue, it is possible to find the bolts that best suit your needs.