Pneumatic torque wrench
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A pneumatic torque wrench is a planetary torque multiplier or a gearbox that is mated to a pneumatic air motor. At the end of the gearbox is a reaction device that is used to absorb the torque and allows the tool operator to use it with very little effort. The torque output is adjusted by controlling the air pressure.
These planetary torque multiplier gearboxes have multiplication ratios up to 4000:1 and are primarily used anywhere accurate torque is required on a nut and bolt, or where a stubborn nut needs to be removed.
The pneumatic torque wrench is sometimes confused with a standard impact wrench, because it looks similar, but is actually a totally different tool. A pneumatic torque wrench is driven by continuous gearing, and not by the Hammers of an impacting wrench. This is why a pneumatic torque wrench has very little vibration, and excellent repeatability and accuracy.
Torque capabilities of pneumatic torque wrenches range from 87Ft lbs, up to a maximum of 35,000Ft lbs.
Air requirements
A pneumatic motor using compressed air is the most common source of power for pneumatic torque wrenches. CFM requirements are usually 20-25 CFM of air consumption per tool.
