A tap wrench is a hand tool

Hand tool

A hand tool is a device for performing work on a material or a physical system using only hands. The hand tools can be manually used employing force, or electrically powered, using electrical current...

 used to turn taps

Taps and dies

Taps and dies are cutting tools used to create screw threads, which is called threading. A tap is used to cut the female portion of the mating pair . A die is used to cut the male portion of the mating pair . The process of cutting threads using a tap is called tapping, whereas the process using a...

 or other small tool

Tool

A tool is a device that can be used to produce an item or achieve a task, but that is not consumed in the process. Informally the word is also used to describe a procedure or process with a specific purpose. Tools that are used in particular fields or activities may have different designations such...

s, such as hand reamers

Reamer

A reamer is a metalworking tool used to create an accurate sized hole. The process is called reaming. They may be used as a hand tool or in a machine tool, such as a milling machine or drill press.-Construction:...

 and screw extractor

Screw extractor

A screw extractor is a tool used expressly for removing broken or seized screws. There are two types; one has a spiral flute structure, which is commonly known by the trademarked name Easy Out; the other has a straight flute structure...

s.

Types

There are two main types of tap wrenches: double-end adjustable wrenches and T-handle wrenches. Double-end adjustable wrenches, also known as bar wrenches, have one threaded handle which is attached to one of the clamps. The clamp is opened to insert the tool and then tightened down against the tool to secure it. This type of tap wrench is used with larger taps and where there is room for a larger wrench, because a T-handle is more compact.

The T-handle tap wrench uses a collet

Collet

A collet is a holding device—specifically, a subtype of chuck—that forms a collar around the object to be held and exerts a strong clamping force on the object when it is tightened, usually via a tapered outer collar. It may be used to hold a workpiece or a tool.A collet is a sleeve with a ...

 to secure the tool. The collet design has two pieces: a threaded "nosecap" and four collet fingers; the collet fingers threaded on the outside so the nosecap is screwed onto them. The nosecap is tapered, which causes the fingers to clamp onto the tool. This style tap wrench is useful in confined spaces or where extra reach is required. The hole which forms the collet fingers may be stepped (have multiple diameters, usually two) to increase the range of cutting tools which may be held by one wrench size.

Numerous sizes of tap wrenches are required to cover the available size range of tool heads. Generally speaking, the smallest size which accommodates the tool head is recommended because it reduces the risk of breakage from excessive force

Force

In physics, a force is any influence that causes an object to undergo a change in speed, a change in direction, or a change in shape. In other words, a force is that which can cause an object with mass to change its velocity , i.e., to accelerate, or which can cause a flexible object to deform...

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