EN 22857:1989

1 Scope and field of application
2 References
3 Basic data
  3.1 Thread profile of nuts
  3.2 Thread profile of tap
  3.3 Tolerance classes of taps
  3.4 Calculation of tap thread dimensions of
      classes 1,2 and 3
4 Manufacturing tolerances on tap threads
  4.1 Major diameter d
  4.2 Pitch diameter d[2]
  4.3 Minor diameter of tap d[1]
  4.4 Tolerance on the angle alpha and half angle
      alpha/2 of thread
  4.5 Cumulative pitch error T[p] over any number of threads
5 Designation and marking of taps
6 Example of calculation of the dimensions of the threaded
  portion of a tap
Annex A - Ground thread taps for ISO metric threads of coarse pitch
Annex B - Ground thread taps for ISO metric threads of fine pitch