6. Glossary

Indice d'enroulement; spring index

Ratio between the average winding diameter of a helix and the wire diameter.

Characteristic; load-length characteristic

Law linking axial force to deflection.

Shot peening; shot peening

The process of violently striking the metal surface with a multitude of small balls to generate residual compressive stresses favorable to the fatigue life of the part.

Pre-training; pre-setting

Pre-forming involves deliberately working the spring beyond its elastic limit (usually in 2 or 3 stages), before putting it into operation on the system, to obtain a given state of residual stress. As a result of plastic deformation, the spring's dimensions will differ from those of the initial shaping....