Where it earns its place
Best-Fit Uses
Clips and small retainers
Applies light holding force between two surfaces with a simple open form.
Compact return arms
Brings a small lever or tab back to position without wrapping a helical coil around the pivot.
Returning a lever or hinged part
Provides a turning force around a pivot so a moving arm comes back toward a preferred angle.
Helping open or close a panel
Can assist or oppose rotation when the spring is arranged around the same pivot as the moving part.
Why this style works here
What This Spring Style Solves
The U-shaped geometry fits flat or open spaces and can combine a simple formed-wire interface with light spring action.
Before you choose it
What to Confirm in Your Assembly
- Show the distance between arms in the free and installed positions.
- Define the contact point on each arm and any sliding that occurs during use.
- Show the pivot or shaft diameter and the free and working leg positions.
- State the required torque at one or more angles and the direction in which the spring is loaded.
- Identify which leg or end is fixed and which one moves with the assembly.
Avoid forcing the wrong spring into the design
When Another Spring Style May Fit Better
Hairpin behavior depends strongly on how the arms are restrained. Pinching the bend or allowing a contact point to move unexpectedly can change the load significantly.
- Torsion springs when a central pivot is available
- Custom wire forms for more complex contact shapes
- Flat springs for very shallow stamped layouts
Keep material selection separate
Environment & Material Direction
Once the working angle, torque and fit around the pivot are known, use the Materials section to choose an alloy for corrosion, temperature or fatigue needs.
For the material families represented in this product's reference configurations, compare Carbon & Alloy Spring Steels, Stainless Steel Spring Materials, Copper Alloy Spring Materials, Nickel & High-Temperature Spring Alloys. Confirm the exact grade and condition for your assembly.
Move from the use case to the specification
Where to Go Next
Related Spring Design Guides
Review the dimensions, working loads and drawing requirements for this spring family.
Engineering Guides for This Product
These guides contain material, wire-diameter or standard data related to this product.
Application questions
Frequently Asked Questions
Is a hairpin spring the same as a torsion spring?
It can create a similar return or closing action, but its open formed-wire geometry and bend behavior differ from a helical torsion spring. The actual load path should define the design approach.
Why does winding direction matter?
A torsion spring is normally intended to tighten around its axis as it is loaded. Reversing that direction can open the coil, change the fit around the shaft and produce a different stress condition.
What should I send for an application review?
Send the assembly drawing or a clear sketch, the working positions, the force or torque you need, expected cycles, environment and quantity. If an existing spring is being replaced, include its dimensions and explain what is not working well in the current design.
Same application family