Heat-treatment
Many springs are bent or coiled while the spring wire is cold.
When the spring is shaped, the so-called yield point of the material is exceeded, which creates inner tension in the spring.
This tension is equalized by subsequently heat-treating the spring.
The heat-treatment ensures that the spring achieves the quality, safety and durability that can be expected from products of Hagens Spring Group.
However, not all springs are heat-treated.
