DIN 2097 is the standard cited for extension spring. This page sets out what the standard controls for this part, reproduces the dimensional table supplied against it, and notes the related designations referenced on drawings.
DIN 2097 — Scope
The table below lists the dimensions catalogued for extension spring — iso / din (series 143) under DIN 2097. The scope of DIN 2097 itself is not summarised here — where a figure matters, confirm it against the published document.
Tolerance & Product Grades
Product grade is a concept from dimensional fastener standards and does not apply to DIN 2097. Tolerances for this part are the limits shown against each dimension in the table.
Dimensions Specified by DIN 2097
| Wire dia d (mm) | Outer diameter De (mm) | Free length Lo (mm) | Initial tension F0 (N) | Rate k (N/mm) | Material | Reference standard |
|---|---|---|---|---|---|---|
| 0.8 | 6 | 30 | 2 | 2.5 | Music wire | DIN 2097 / GB/T 23935 |
| 1.0 | 8 | 40 | 4 | 4.0 | Music wire | DIN 2097 / GB/T 23935 |
| 1.2 | 10 | 50 | 6 | 6.5 | Music wire | DIN 2097 / GB/T 23935 |
| 1.6 | 14 | 70 | 10 | 12.0 | Music wire | DIN 2097 / GB/T 23935 |
| 2.0 | 18 | 90 | 18 | 20.0 | Music wire | DIN 2097 / GB/T 23935 |
| 2.5 | 22 | 120 | 28 | 32.0 | Music wire | DIN 2097 / GB/T 23935 |
| 3.0 | 28 | 150 | 45 | 55.0 | Music wire | DIN 2097 / GB/T 23935 |
| 4.0 | 40 | 200 | 90 | 110.0 | Music wire | DIN 2097 / GB/T 23935 |
Companion Standards
A complete specification for extension spring — iso / din (series 143) normally cites several documents: one for the geometry, one for the material or mechanical properties, and one for the finish. DIN 2097 is one of them, not all of them.
When to Specify DIN 2097
DIN 2097 is still widely used in European mechanical engineering and as a cross-reference on legacy drawings; its ISO equivalent is preferred for new designs.
Custom manufacturing · Made to drawing
Need a spring to this standard in a non-standard size?
Parts built to DIN 2097 are already in the catalog, so a special is usually a variation on existing tooling rather than a new design — which is what keeps the cost down.
Minimum order from 2,000 pieces; samples within 7 days of drawing approval.
