AS 1721-1985

Specifies requirements for single start parallel metric screw threads having the ISO basic profile for triangular screw threads, covering the size range from 1 mm diameter to 355 mm diameter inclusive. Provides for a coarse pitch series, a fine pitch series and a constant pitch series, the latter intended for use in applications for which either the coarse or fine pitch series are unsuitable. Gives information on screw thread parameters, tolerances, deviations, thread classes, designation and symbols. Appendices are included giving the basis of the tabulated values, guidelines (with examples) for calculating the limits of size of untabulated screw threads and notes on the production of screw threads.