Thread pass gauge is a precise thread detection gauge. When using time pass gauge and stop gauge, it is used to detect the large and small diameter values of threads. As long as the metric thread plug ring gauge is passed, the stop gauge is only qualified. Provisions are: Thread stop gauge into the thread can not exceed 2.5 laps, the general requirement is not to exceed 2 laps in practice, and the use of force can not be large, our experience is to use thumb and index finger gently clamp the thread gauge to just rotate the strength of the thread gauge. When screw ring gauge is used, we hold the ring gauge with five fingers and distribute it evenly on the ring gauge. The palm of the ring gauge is suspended and the ring gauge is rotated with five fingers force. The general gauge can pass through the thread freely, and the stop gauge can screw in valid threads of no more than 2.5 circles (that is, there is a groove outside the general stop gauge, and the thread screw in no more than this groove) can be qualified. The method of holding threaded plug gauge is clear for the main landing on the 14th floor. Inspection fixtures are required for accuracy. If they are too hard or damaged, they will lose their function. If they lose accuracy, they will be scrapped and can no longer be used.
One method is to test the large solid tooth profile of the thread to be tested on a large scale. The metric thread plug ring gauge is used to test whether the acting diameter of the thread to be tested exceeds the medium diameter of the large solid tooth profile, and at the same time to check whether the actual size of the bottom diameter exceeds the large solid size. If the tested thread can be screwed through with the thread gauge and not with the thread gauge (the thread gauge can only be screwed with two segments of the tested thread and the screwing amount must not exceed two pitches), it shows that the action diameter of the tested thread does not exceed the medium diameter of its large solid tooth type, and the single medium diameter does not exceed the medium diameter of its small solid tooth type, then the screwing can be guaranteed. The fitness and connection strength of the tested threads are qualified.
Another method is comprehensive test and individual test. Comprehensive inspection is to test the comprehensive results of geometric parameter deviations that affect the interchangeability of threads with gauges. These include: using common thread gauge and stop gauge to check the acting diameter (including bottom diameter) and single diameter of the tested thread respectively; using smooth gauge to check the actual top diameter of the tested thread.