A torque wrench is a tool used to precisely apply a specific torque to a fastener such as a nut or bolt. It is usually in the form of a socket wrench with special internal mechanisms. It was invented by Conrad Bahr in 1918. It was designed to prevent over tightening nuts and bolts. A torque wrench is used where the tightness of nut and bolts is crucial. It allows the operator to measure the torque applied to the fastener so it can be matched to the specifications for a particular application. Torque wrenches are of various types such as digital wrench, angular wrench etc.
Torque wrenches are often considered and used as “tools” rather than true measuring “instruments”. They provide a “visible” measure of torque (dial indicating, flat beam TW). They are used to control torque in assembly and fastening operations.
