A power wrench is type of
wrench that is powered by other means than human force. A typical
power source is
compressed air
Compressed air is air kept under a pressure that is greater than atmospheric pressure. Compressed air in vehicle tires and shock absorbers are commonly used for improved traction and reduced vibration. Compressed air is an important medium for t ...
. There are two main types of power wrenches: ''
impact wrench
An impact wrench (also known as an impactor, impact gun, air wrench, air gun, rattle gun, torque gun, windy gun) is a socket wrench power tool designed to deliver high torque output with minimal exertion by the user, by storing energy in a ro ...
es'' and ''air ratchet wrenches'' or ''pneumatic ratchet wrenches''.
[.]
Air ratchet wrench
An air ratchet wrench is very similar to hand-powered
ratchet wrenches in that it has the same square drive, but an
air motor
A pneumatic motor (air motor), or compressed-air engine, is a type of motor which does mechanical work by expanding compressed air. Pneumatic motors generally convert the compressed-air energy to mechanical work through either linear or rotary ...
is attached to turn the socket drive. Pulling the trigger activates the motor which turns the socket drive. A switch is provided to change which direction the socket drive turns.
This type of power wrench is designed more for speed and less for torque. If high levels of torque are desired an impact wrench should be used.
References
Bibliography
*{{Citation , last = Webster , first = Jay , title = Outdoor Power Equipment , publisher = Cengage Learning , year = 2000 , url = https://books.google.com/books?id=p3ZHkkm4QU0C , isbn = 978-0-7668-1391-5.
Wrenches