Pneumatic torque wrench is a torque wrench with high-pressure air pump as the power source. A torque multiplier with three or more epicyclic gears is driven by one or two powerful pneumatic motors. The torque is controlled by adjusting the gas pressure. In order to allow specific torque demand settings, each tool is equipped with a special comparison chart and correction report for the torque of the air pressure. For further application, the pneumatic wrench can be equipped with a torque sensor at the same time, so that the output torque is more accurate. After obtaining the required torque, the air supply can be shut down manually or automatically using a suitable loop system.
Torque calculation formula of rotating object is T=9550P/n
P is power in kW, n is speed in rpm, r/min torque in Nm torque is the product of force and arm length. For the wrench, 200NM means that the distance between the wrench and the torque point of the core wrench is one meter during the wrench rotation, and the applied force is 200N. According to the definition of torque and lever principle, the torque generated by applying 100N force at 2M of wrench or 400N force at 0.5M of wrench is 200NM.
How to calculate the force arm of the pneumatic wrench? The main problem is that the output force of the pneumatic motor is obtained by multiplying the air supply pressure by the effective area of the pneumatic piston, and then is calculated by the torque transmission of each component of the transmission mechanism. It is difficult to understand without the dimensional drawing or mapping data of internal components.
It can be tested in practice. For example, use a pneumatic wrench to tighten a disk with a radius of 1 meter, and see how much force is required to keep the disk from rotating.
Torque is the product of force and arm length. For the wrench, 200NM means that the distance between the wrench and the torque point of the core wrench is one meter during the wrench rotation, and the applied force is 200N. According to the definition of torque and lever principle, the torque generated by applying 100N force at 2M of wrench or 400N force at 0.5M of wrench is 200NM. General pneumatic wrenches have torque of 10 to 30 to 40 Nm, and 200 Nm pneumatic wrenches have not been heard of, so they thought they were machine operated.
The "force" acting on the screw cap or nut is generally expressed in terms of torque. If you have to calculate the force, the calculation method is the same as above, and then divide by 2. Because the force acting on the nut is a "couple".
