PROCEDURE FOR RECOVERY OF SPRINGS Russian patent published in 2011 - IPC C21D9/02 B21F35/00 B23P6/00 

FIELD: metallurgy.

SUBSTANCE: spring is heated to temperature of quenching and is drawn in heated condition at pitch exceeding pitch of finished spring. Not cooled spring is heat treated. Cold spring is subjected to shot casting cold hardening, whereupon its coils are plastic hardened with axial load amounting to (10…300)F₃, where F₃ is force of spring at maximal deformation including deformation with preliminary usual spring hardening by ageing in compressed condition. Further, repeated load is applied increased proportionally to ratio of required camber to camber at application of primary load. Loads can be of vibration type. Spring setting is performed at higher requirements to power parameters.

EFFECT: upgraded quality and service life of springs at recovery of their flexible properties.

4 cl