This standard defines the execution tolerances of the threaded part of ground thread dies for ISO metric triangular profile threads with tolerances 4h to 7h, 4g to 9g, 4e to 9e (threads with precision grade 3 are therefore not considered as they not normally obtainable with supply chains). It is valid for hand dies and for any type of machine die that have the same diameters and pitches. The appendix establishes, for each thread, the execution tolerances of the threaded part of the dies for the following screw tolerance ranges: 4h 5h 6h 7h e 4g 5g 6g 7g 8g 9g 4e 6e 7e 8e 9e
UNI 7682-1977 history
1977UNI 7682-1977 Statistical methods are used for quality inspection. Statistical acceptance procedure for variables based on eigenvalues