Engineering Notes & Manufacturing Tolerances
Comprehensive tolerance specifications for compression, extension, and torsion springs. Conforming to DIN EN 15800, ISO 10243, and DIN 2097 standards.
TOSTA standard and customized elastic components are manufactured strictly in accordance with international precision guidelines, ensuring optimal fit, zero bind, and repeatable dynamic response across high-volume assemblies.
- • All tolerance baselines are established at standard 20°C ambient room temperature.
- • Spring rate (k) tolerance applies across the linear elastic deflection range (20% to 80% stroke).
- • For ultra-tight custom tolerances (e.g. medical surgical devices or aerospace avionics), contact our application engineering team.
Compression Springs Tolerances (DIN EN 15800 Grade 1 & 2)
| Geometric & Mechanical Parameter | Standard Tolerance Grade | Precision Custom Grade |
|---|---|---|
| Wire Diameter (d) | ±0.02 mm | ±0.01 mm |
| Outer Diameter (OD / D) | ±0.1 mm | ±0.05 mm |
| Free Length (L₀) | ±0.5 mm | ±0.2 mm |
| Spring Rate / Stiffness (k) | ±10% | ±5% |
| End Squareness & Perpendicularity | ±3° | ±1.5° |
Extension Springs Tolerances (DIN 2097 Grade 1 & 2)
| Geometric & Mechanical Parameter | Standard Tolerance Grade | Precision Custom Grade |
|---|---|---|
| Wire Diameter (d) | ±0.02 mm | ±0.01 mm |
| Outer Diameter (OD / D) | ±0.1 mm | ±0.05 mm |
| Free Length Inside Hooks (L₀) | ±1.0 mm | ±0.5 mm |
| Initial Tension (P₀) | ±15% | ±8% |
| Hook Opening Gap | ±0.3 mm | ±0.15 mm |
Torsion Springs Tolerances (DIN 2088 / ISO 8458)
| Geometric & Mechanical Parameter | Standard Tolerance Grade | Precision Custom Grade |
|---|---|---|
| Wire Diameter (d) | ±0.02 mm | ±0.01 mm |
| Outer Diameter (OD / D) | ±0.1 mm | ±0.05 mm |
| Free Arm Angle | ±5° | ±2° |
| Torsional Moment @ Rated Angle | ±10% | ±5% |
Need Expert Engineering Consultation?
TOSTA application specialists are available to analyze your assembly stack-up and calculate optimal spring dimensions.
Contact Engineering Team Mr. Wang +86 130-1246-1618