NF ISO 529

Short machine taps and hand taps

ISO 529:2017 specifies the general dimensions of short machine taps and hand taps. These dimensions, established as functions of the thread diameter and pitch, are the following:

- length of thread (maximum);

- overall length;

- shank diameter and dimensions of driving square;

- dimensions of the connecting portion between the shank and threaded part.

ISO 529:2017 is applicable to taps intended for cutting the following threads:

a) ISO metric threads:

• - coarse pitch;
• - fine pitch;

b) ISO inch threads:

• - "Unified Coarse" series (UNC) and "Unified Fine" series (UNF);

c) Inch threads, non-recommended:

• - "British Standard Whitworth" (BSW) and "British Standard Fine" (BSF);
• - "British Association" (BA).

NOTE 1 The overall length, thread length and diameters of shank for taps whose thread diameter and pitch are not listed in tables are given in Table A.1.

NOTE 2 Annex B gives an abstract from ISO 237 for shank diameters and size of driving squares, for information.

NOTE 3 Technical specifications for taps covered by this document (including marking) are given in ISO 8830.

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