Die springs
Foster Springs distributes Bordignon die springs, made in Italy, in metric ISO 10243 series and in inch series. Find the size that replaces your spring, then ask for the price and lead time.
What specifies a die spring
Two die springs are interchangeable when they share the hole, the rod and the free length. The colour then gives the stiffness.
- DHole diameter (housing). It sets the outside diameter of the spring.
- dDiameter of the rod that guides the spring.
- L0Free length, at rest.
- ●Colour: the load class, from light to super heavy.
- sWorking stroke. Stay under the long-life stroke for the longest spring life.
Die spring colour code chart
The colour gives the load class, but the code changes from one series to the next. Strokes are a share of the free length, from the Bordignon catalogue.
Metric ISO 10243 series
| Colour | Load | Bordignon | Long-life stroke | Maximum stroke |
|---|---|---|---|---|
| Violet | Extra light | 1L | 35% | 50% |
| Green | Light | 1S | 30% | 40% |
| Blue | Medium | 2S | 25% | 37.5% |
| Red | Heavy | 3S | 20% | 30% |
| Yellow | Extra heavy | 4S | 17% | 25% |
| Brown | Super heavy | 5S | 10% | 15% |
Inch series (US)
| Load | Bordignon | Dayton MaxLife | Long-life stroke | Maximum stroke |
|---|---|---|---|---|
| Medium | USB, blue | M, blue | 25% | 40% |
| Medium heavy | USR, red | MH, red | 20% | 30% |
| Heavy | USG, gold | H, yellow | 15% | 25% |
| Extra heavy | USV, green | EH, green | 15% | 20% |
The Bordignon BK series (black) carries an exceptional load over a short stroke, given for each size. Dayton recommends an operating range per class: M 25 to 35%, MH 20 to 25%, H 15 to 20% and EH 15%.
Common questions
What is a die spring?
A die spring is a heavy-duty compression spring made of steel wire with a rectangular or oval section. It works in a hole, guided by a rod, in stamping and forming dies, presses, molds and fixtures.
What is the difference between a die spring and a compression spring?
A standard compression spring uses round wire and is made to the size of your part. A die spring uses flat-section wire and follows standard sizes. It carries more load in the same space, and a die spring from one brand can be replaced by a spring of the same size from another brand.
Do the colours mean the same thing in every series?
No. Green is a light load in the ISO series and an extra heavy load in the US series. Red is a heavy load in the ISO series and a medium heavy load in the US series. Check the series before you compare two colours.
I only have a part number. How do I find the equivalent?
Enter a Dayton MaxLife part number in the cross-reference finder. For Danly, Raymond, Lamina or another brand, pick the hole diameter and the free length in the finder, or send us the part number in a quote request.
A spring to replace or a part to develop?
Send your drawing or a photo, or call us at 450 372-0812.