update:

EN 13906-3:2014 Cylindrical helical springs made from round wire and bar - Calculation and design - Part 3: Torsion springs - better quality
EN 16983:2016 Disc springs - Quality specifications - Dimensions - added new standard
EN 16984:2016 Disc springs - Calculation - added new standard

still complete

new links:

[link Point to another website Only the registered members can access]
or

[link Point to another website Only the registered members can access]