How to choose torque wrench precision?
There is also a way to calculate the CP value, the CP value is greater than 1.33, in the vicinity of 1.66 best.
If you learned the quality management and statistics, should know that the accuracy is very simple: take bolt wrench requirement of tolerance of 50%, 5% with a wrench to guarantee the precision of the torque wrench with 10% accuracy, 10% accuracy 20% accuracy of torque, no problem.
As for the torque wrench verification is another problem, according to the requirements of measurement, calibration of 10% precision wrenches need more than 3% accuracy verification device, verification of 3% precision wrench needs at least 1% precision calibration device.
