Starting

After cold forming, all ­springs ( except those sold by the meter ) are subjected to heat treatment. This tempering increases the toughness and reduces residual stresses.

End turns

The designation "n" in the catalog indicates the ­number of spring coils. In addition, there are two additional end coils. For compression springs with a wire thickness of less than 0.5 mm, the end coils are applied. For springs with a wire thickness of 0.5 mm or more, the end coils are additionally ground over a circumference of approx. 270°.

Spring calculation

The calculation of the catalogue springs was carried out according to DIN 2095-EN 15800 for compression springs, DIN 2097 for tension springs and DIN 2194 for torsion springs, each according to quality grade 2.

Production balancing

The production of springs requires production compensation in order to be able to comply with the specified values. With our standard compression springs, compensation is carried out over the length L0, so the springs can be slightly longer than L0 before they are first pressed onto the block.

Shot blasting

To increase fatigue strength, the springs can be hammered with steel or glass balls. Our stock springs are not shot peened. If desired, the springs can be shot peened at a later date for an additional charge.

surface protection

The springs made of spring steel wire are lightly oiled. The springs made of stainless spring steel have no surface treatment. On request, we can supply the ­springs with any corrosion protection.

Eyelets

The standard tension springs have ­a full German eyelet at both ends in accordance with DIN 2097 Figure 3. The position is normally 0 degrees. The eyelets have no opening. However, we can cut an eyelet opening to your specifications at short notice.

Set

When setting or pre-setting, the compression spring is compressed to the block length and loses length in the process. This process reduces the relaxation of the spring during operation. The standard springs are not set and can therefore be slightly longer than L0.

Tolerances

The manufacturing tolerances for compression springs correspond to EN 15800, grade 2, or for tension springs DIN 2097, grade ­2.

preload

When winding tension springs, a corresponding twisting of the wire creates a force that presses the windings against each other . The force that separates the windings from each other is called pre-tension.