Detection of common thread:
For the general standard thread, the thread ring gauge or plug gauge is used to measure. In the measurement of external thread, if the thread "over the end" ring is good screw, and the "stop end" ring gauge is not screw into, it indicates that the processed thread meets the requirements, otherwise it is unqualified.
The screw plug gauge is used to measure the internal thread in the same way. In addition to the thread ring gauge or plug gauge measurement can also be used to measure other measuring tools, with thread micrometer measurement measurement thread diameter, with tooth thickness vernier caliper measurement trapezoidal thread diameter and worm joint diameter tooth thickness, using measuring needle according to the three needle measurement method measurement thread diameter.