How to debug the pneumatic torque wrench and explain the fault repair method in detail

When an external force Q is applied to the pneumatic wrench, that is, when the wrench is in use, when Q increases to a certain value (the moment the force acting on the square tenon reaches the set value M), the entire wrench will lose its internal balance and the wrench rod will lose its balance. Rotate counterclockwise upwards around the pin 1 to drive the lever to rotate clockwise around the pin 2. When the knocking position of the lever turns to collide with the inner wall of the guide sleeve + the inner wall of the guide sleeve will prevent further rotation. At this time, if Cancel the external force. Due to the existence of the connecting plate angle a3, under the action of the spring force, the whole system will return to the initial state. That is to say, there are two noises during the whole movement. The first sound is the sound of lever tapping the guide sleeve, the sound is louder, the second sound is the impact sound of the adjusting screw and the sleeve when the system is reset, the sound is smaller, that is, the wrench The "click" sound when calling the police. During operation, when the lever hits the guide sleeve, the operator will have an instant sense of relief.

Debugging of pneumatic torque wrench



After the air impact wrenches is used for a certain period of time or frequency, the indication value will appear out of tolerance, which requires the wrench to be checked and debugged regularly. Based on the previous analysis, we can foresee that there are two main phenomena for the wrench indication value:


① The change of △x causes the overall deviation of the indication value. That is, the indication output of the wrench is the same value higher or lower than the nominal value at each point.

The debugging method is: if the indicated value is shifted as a whole, we can realign the ruler by turning the adjustment wheel.


②The output slope of the wrench does not meet the requirements. Take the NB-100G wrench as an example. When the output low point of 30Nm of the wrench is suitable (the low point can be reached by screwing in or retreating the adjusting wheel), the actual output of the wrench has two possibilities, namely the actual output line 1 and the actual output line 2, that is, at lOONm or Lower than 100, such as actual output line 1, or higher than 100, such as actual output line 2.


The debugging method is: adjust a3 by adjusting the height of the adjusting screw on the lever assembly. Make a3 reach the required value. (Debugging must be performed on the torque wrench testing instrument through a flat screwdriver or a hexagonal screwdriver for troubleshooting)


It is simply summed up as "one look at two turns three on stage". "One look" is to see whether the wrench components are complete from the appearance. If the wrench is incomplete, the missing parts should be filled in. "Second rotation" is to turn the ratchet wheel by hand and adjust the wheel to see if it is stuck flexibly. Inflexible rotation must be a problem. ; "Three on the stage" is to put the torque wrench on the verifier for testing to see if the indicated value is within the accuracy level.