An adjustable wrench is a wrench that can be adjusted to different settings, usually for size, to fit a variety of hexagonal nuts. The adjustable wrench is often considered one of the most versatile of tools. While ordinary wrenches can often only be used on a particular size of nut, adjustable wrenches can fit a much wider variety of sizes.
In some cases, an adjustable wrench may be called a Crescent® wrench. It should be noted this terminology, while common in the vernacular, refers to a specific brand name. Crescent® wrenches are so named because the head, when opened, roughly forms the shape of a crescent moon.
Typically, when looking for a wrench to fit a bolt, it may be a matter of trial and error. While sometimes it is possible to get it right the first time, many who do not work with hand tools every day seldom will. Further complicating the matter is that some wrenches and nuts use English measurements while others use metric. With an adjustable wrench, there is no need for a match.
The adjustable wrench works by turning a screw usually located at the bottom of the head. In most cases, this screw can easily be turned by hand. However, in other cases, dirt, grime and dried grease may built up on the screw, making it more difficult to turn. This can usually be remedied with a cleaning and some additional lubricant. In most cases, only one portion, usually the bottom jaw, of the adjustable wrench will actually turn. The top portion usually remains stationary.
One of the drawbacks to the adjustable wrench is the fact that its larger head size, when compared to standard wrenches, means it may be harder to fit in tight spaces. To help remedy this situation, there are sizes of adjustable wrenches as well. These help with the ability to get in and turn around in those tight spaces.
In addition to standard adjustable wrenches, other types of wrenches may also be considered adjustable. A pipe wrench, for example, functions in a way very similar to an adjustable wrench. It has a screw in order to make the adjustments, but many times it is the upper jaw that moves instead of the lower jaw.
For those who choose not to waste their time screwing the adjustable wrench to the needed size, it is possible to find wrenches which do this automatically at the push of a button. This is often referred to as the automatic adjustable wrench. This tool will help those who have a hard time turning the screw to the exact size needed.