What Is a Ratchet Wrench?

A ratchet wrench is a tool used to loosen or tighten bolts. It consists of a socket attached to a handle that contains a ratcheting mechanism, usually on top of a square drive. A ratchet wrench can be used to turn a bolt or screw in one direction, and when the tool is turned, it can be locked into place to hold that fastener at a specific torque value, making it easier to remove the bolt. A ratchet wrench may have several attachments, including extensions, which can increase the reach of the tool and help to access hard-to-reach fasteners. A crow's foot adapter is another type of extension, which resembles an open spanner with a square hole for a ratchet. These types of adapters are often used to reach inaccessible or recessed fasteners.

A ratcheted wrench can also have a handle with a built-in torque indicator, which allows the user to check if the tool is properly tightened or loose. Some models have a locking feature that prevents the ratchet from accidentally turning backwards when it's not being used, helping to protect the fastener head from damage and preventing over-tightening.

Ratchet wrenches come in a variety of sizes and styles to suit the needs of a wide range of fasteners. Some have a flexible head that can be moved to different angles, which can be useful in cramped spaces. Other ratchets have a fixed head, which can be used in more demanding situations. Some ratchets have a lock that keeps the socket from falling off the drive tang; the lock can be released with a push button.

Some ratchets have a higher tooth count than others, which reduces the amount of movement needed to turn the hex drive. Ratchets with a higher tooth count also make it possible to take apart fasteners in a smaller space than those with fewer teeth, because the wrench can be turned more slowly and still move the hex head into position.

Many ratchets can be joined together to form an extendable tool, which is ideal for working in narrow spaces. Some ratchets have reversible drives, which allow the user to quickly change the direction of the wrench's motion in a single step. Other ratchets have knurled handles for improved gripping on nuts or bolts.

In some ratchet wrenches, the square drive is replaced with a hex drive to accommodate more bolts. Other tools, such as a socket wrench, can be used to work on fasteners that are too large for a ratchet to fit into. Socket wrenches are commonly available in sets with different size and type sockets to suit various fasteners, and are designed to work on both hex and square drive fasteners. Sockets are attached to ratchets by inserting the bottom of the socket into the square drive on the ratchet's driver and then pushing or tapping the socket onto the drive tang until it snaps into place. Sockets are normally marked to show the corresponding fastener size and type.