This Part of BS 1726 provides guidance on methods of specifying, tolerancing and testing of parallel sided helical compression springs manufactured from circular section material.
Two grades of tolerance, 1 and 2, are given for circular section springs.
Three types of end coils are provided for, i.e. open end, closed end, and closed and ground end, the last of these being applicable only to springs where the diameter or axial dimension of material is 0.5 mm or greater.
This Part of BS 1726 differentiates between springs that have or have not been stress relieved after forming (designated group A), and springs, the material of which has undergone a structural change by
heat treatment after forming (designated group B).
This standard gives two methods of specifying springs for general purposes and one method of testing springs.