For extension springs, DIN 2097 is the governing document for the dimensions listed below. Mechanical and performance requirements for this part family are set by its own standards, not by the bolt and screw property-class documents.
DIN 2097 — Scope
The table below lists the dimensions catalogued for extension springs 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) | Inner diameter Di (mm) | Outer diameter De (mm) | Free length Lo (mm) | Active coils n | Max working force (N) | Rate k (N/mm) | Material | Reference standard |
|---|---|---|---|---|---|---|---|---|
| 0.5 | 3.5 | 4.5 | 20 | 12 | 5.0 | 0.807 | Spring steel | DIN 2097 / EN 15800 |
| 0.6 | 4.5 | 5.7 | 25 | 12 | 6.8 | 0.807 | Spring steel | DIN 2097 / EN 15800 |
| 0.8 | 5.5 | 7.1 | 30 | 12 | 13 | 1.35 | Spring steel | DIN 2097 / EN 15800 |
| 1.0 | 7.0 | 9.0 | 40 | 15 | 20 | 1.29 | Spring steel | DIN 2097 / EN 15800 |
| 1.2 | 8.5 | 10.9 | 50 | 15 | 28 | 1.50 | Spring steel | DIN 2097 / EN 15800 |
| 1.5 | 11.0 | 14.0 | 60 | 15 | 43 | 1.71 | Spring steel | DIN 2097 / EN 15800 |
| 2.0 | 13.0 | 17.0 | 80 | 15 | 84 | 3.13 | Spring steel | DIN 2097 / EN 15800 |
| 2.5 | 17.0 | 22.0 | 100 | 15 | 130 | 3.48 | Spring steel | DIN 2097 / EN 15800 |
| 3.0 | 22.0 | 28.0 | 120 | 15 | 170 | 3.43 | Spring steel | DIN 2097 / EN 15800 |
| 4.0 | 28.0 | 36.0 | 160 | 15 | 320 | 5.16 | Spring steel | DIN 2097 / EN 15800 |
| 5.0 | 36.0 | 46.0 | 200 | 15 | 490 | 5.99 | Spring steel | DIN 2097 / EN 15800 |
| 6.0 | 46.0 | 58.0 | 250 | 15 | 670 | 6.09 | Spring steel | DIN 2097 / EN 15800 |
Equivalent Standards
Where direct equivalents exist (ISO ↔ DIN, ISO ↔ ASME), they are listed on the parent Extension Springs page.
Always confirm against the dimensions on this page, since some "equivalent" standards differ in tolerances and head geometry.
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.
