This standard establishes the execution tolerances of the threaded part of ground thread taps for ISO metric threads with triangular profile, coarse and fine pitch, with nut tolerance ranges 4H to 8H and 4G to 6G (tolerance ranges are excluded 7G and 8G as they are considered not usually performed with rectified thread taps). It is valid for short ISO taps and also for any other type of taps that have the same diameters and pitches. Appendices A and B establish, for each coarse and fine pitch thread, the manufacturing tolerances of the threaded part of the taps for the following tolerance ranges of the nuts: 4H 5H 6H 7H 8H and 4G 5G 6G
UNI 7456-1975 history
0000 UNI EN 22857-1990
1975UNI 7456-1975 Ground thread taps for ISO metric threads. Deviation of the threaded part of the product