Canted Coil Springs Loss of Deflection: Causes, Fixes & Design Guide
Understand why canted coil springs lose deflection during operation and how to prevent failure. Learn key design factors, materials, and engineering solutions from Hunan Handa.
Understanding Loss of Deflection in Пружины со скошенными витками: Engineering Causes, Diagnostic Methods, and Proven Solutions (with Handa Expertise).Canted coil springs—also called slanted coil springs, canted springs, or spiral spring EMI shielding rings—are widely used in critical sectors such as medical devices, aerospace connectors, electric mobility, semiconductor equipment, and EMI shielding systems. Among all performance-related issues, one failure mode stands out due to its direct impact on system reliability: Loss of Deflection, also known as insufficient compression stroke, reduced elastic recovery, or premature spring softening.
This article combines the readability of an SEO blog with the depth of a technical white paper, offering engineers, designers, and procurement specialists a 360° understanding of why canted coil springs lose deflection, how to diagnose the root causes, and what corrective actions ensure long-term functional stability. The analysis is based on mechanical engineering principles, materials science insights, and extensive application experience—especially from Hunan Handa, a leading manufacturer of precision canted coil springs and EMI shielding solutions.
1. What Exactly Is “Loss of Deflection” in Canted Coil Springs?
(Primary Keywords: Canted Coil Spring Deflection Failure, Loss of Deflection in Spiral Spring EMI Shielding)
Loss of deflection refers to a condition where a canted coil spring:
In critical systems such as medical connectors or EMI gaskets, loss of deflection leads to:
This failure mode is often progressive and may go unnoticed until catastrophic failure occurs.
2. Typical Scenes Where Loss of Deflection Occurs (Problem Phenomena + Consequences)
2.1 High-load mechanical locking mechanisms
Spring becomes over-compressed, losing its recovery ability → lock cannot engage.
2.2 EMI spiral spring shielding rings in medical devices
Constant compression + temperature cycling → shielding gap appears → EMI leakage and certification failure.
2.3 High-cycle connectors
Tens of thousands of mating cycles → spring force drops, contact resistance rises.
2.4 Improper groove design
Groove too deep or too narrow → mechanical confinement → spring cannot reach its usable stroke.
3. Engineering Causes of Loss of Deflection (Mechanics + Materials + Design)
Below are the four most likely core causes, presented with mechanical and materials science reasoning.
Cause 1: Excessive Load or Over-Compression (Most Common)
Mechanics:
When compression force exceeds the elastic limit, the spring enters the plastic deformation region.
Stress Model
σ=FA\sigma = \frac{F}{A}σ=AF
When σ ≥ σ_yield, the canted coil deforms permanently.
Typical Field Symptoms
Why It Happens
Cause 2: Improper Groove Geometry (Design-Level Failure)
The groove defines the spring’s working envelope. Incorrect geometry severely limits deflection.
Common groove mistakes
Text-based Diagram (SEO-friendly)
Correct Groove: Too Narrow Groove:
| | | | |
| O | → | O | |
| | | | |
Engineering Effect
Reduced available stroke → early loss of deflection.
Cause 3: Material Yield Strength or Temperature Resistance Too Low
Material Problems Include
Material Performance Comparison
| Материал | Yield Strength | Temperature Resistance | Suitability |
| Elgiloy® | ★★★★★ | ★★★★★ | EMI, high-cycle, medical |
| 17-7PH | ★★★★☆ | ★★★☆☆ | Mechanical components |
| Inconel X-750 | ★★★★★ | ★★★★★ | High-temperature sealing |
| 316L | ★★☆☆☆ | ★★☆☆☆ | General use, low stress |
Заключение
If material strength < applied load → loss of deflection is inevitable.
Cause 4: Fatigue Failure from High-Cycle Repetition
Canted coil springs used in connectors often experience 10,000–100,000 cycles.
Fatigue Stress Formula
σf=σmax−σmin\sigma_f = \sigma_{max} – \sigma_{min}σf=σmax−σmin
Typical Symptoms
4. Solutions: How to Prevent Loss of Deflection (Actionable Engineering Guidelines)
Below are targeted solutions linked directly to each root cause.
Solution for Cause 1: Over-Compression
Solution for Cause 2: Incorrect Groove Design
Recommended Geometry
Loss of Deflection Design Table
| Groove Issue | Effect | Solution |
| Too Narrow | Confinement | Increase width |
| Too Deep | Limited stroke | Reduce depth |
| Incorrect Dia. | Preload | Adjust tolerance |
Solution for Cause 3: Material Mismatch
Material Selection Guide
Additional Material Treatments
Solution for Cause 4: Fatigue
5. Key Selection Standards & Preventive Measures
Selection Standards
Preventive Maintenance
6. Extended Questions: Cost, Alternatives, Testing
6.1 Cost Considerations
6.2 Alternatives to Canted Coil Springs
6.3 Test Methods for Deflection Loss
Conclusion: Ensuring Long-Term Performance with Precision Engineering — Why Hunan Handa Leads the Industry
Loss of deflection in canted coil springs is a complex engineering issue involving load, material properties, groove design, and fatigue stress. By combining the right material, optimized groove geometry, precise coil design, and proper installation methods, engineers can significantly extend spring life and system reliability.
HANDA is one of the industry’s leading manufacturers specializing in precision canted coil springs, spiral spring EMI shielding rings, high-cycle connector springs, and custom-engineered metallic seal solutions.
With advanced wire forming technology, strict process control, and in-house force-deflection testing, Handa ensures every spring maintains stable deflection characteristics—even under extreme load, temperature, or cycling conditions.
For high-reliability applications in medical, aerospace, semiconductor, or EMI shielding systems, Handa’s canted coil springs deliver proven performance, engineered precision, and long-term stability.
Emai: sale01@handashielding.com