Quality Control & Testing for Custom Springs
Every spring is produced, inspected, and tested based on your drawings, tolerances, and application requirements.
Industry Reality
Why Springs Require Rigorous Testing
Same Drawing, Different Force
Identical specs can produce varying load characteristics without proper process control.
Samples Pass, Production Fails
Without batch control, mass production quality often diverges from approved samples.
No Report, No Traceability
Missing inspection records make quality issues impossible to diagnose or prevent.
Lab Works, Assembly Fails
Springs tested in isolation may fail when integrated into real-world assemblies.
For springs, small dimensional deviations lead to big functional failures.
Our Quality Control Logic for Custom Springs
We don't just inspect dimensions. We control three interconnected layers that determine spring performance.
Drawing-Based Control
- Wire diameter verification
- Outer diameter (OD) measurement
- Free length inspection
- Hook/leg geometry check
- Tolerance per customer specs
Function-Based Control
- Load / force at specified height
- Spring rate verification
- Deflection testing
- Torque measurement (torsion)
- Fatigue performance
Batch-Based Control
- First article inspection (FAI)
- In-process sampling
- Statistical process control
- Final random inspection
- Batch traceability records
We don't just test dimensions — we verify Dimensions + Mechanical Performance + Batch Consistency together.
Incoming Material
Incoming Material Inspection
Raw material quality directly impacts spring performance. Every wire batch is verified before entering production.
- Spring wire diameter verification against specs
- Material grade confirmation with mill certificates
- Surface condition check (rust, scratches, defects)
- Lot number tracking for full traceability
Material inconsistency is the first cause of unstable spring performance. We catch it before production begins.
In-Process QC
In-Process Inspection
Quality is built during production, not just verified afterward. We monitor critical parameters throughout the manufacturing process.
Inspections are adjusted based on spring type and application requirements — not fixed templates.
Mechanical Performance Testing
Different spring types require different tests. We verify the mechanical properties that matter for your specific application.
Compression Springs
- Load at specified height
- Spring rate verification
- Solid height measurement
- Squareness check
Extension Springs
- Initial tension verification
- Load at extension length
- Hook strength testing
- Spring rate consistency
Torsion Springs
- Torque vs angle testing
- Direction verification
- Leg position accuracy
- Angular deflection range
Fatigue Testing (When Required)
For critical applications requiring long-term reliability, we perform cycle testing to verify performance over repeated use.
Measurement Equipment
Purpose-matched tools for spring inspection — what matters is matching the equipment to your spring type.
Digital Calipers
Precision dimensional measurement
Micrometers
Wire diameter verification
Spring Load Testers
Force & rate measurement
Torque Testers
Torsion spring testing
We also build custom fixtures based on your drawings for specialized inspection requirements.
Dimensional Verification
Comprehensive measurement protocols ensure every critical dimension meets your exact specifications.
Wire Diameter
Verified at multiple points along the spring using digital micrometers. Tolerance typically held to ±0.01mm for precision applications.
Outer & Inner Diameter
Measured using digital calipers or optical comparators for tight-tolerance applications requiring consistent fit.
Free Length & Solid Height
Critical for compression springs — ensures proper installation fit and prevents over-compression damage.
Corrosion Testing
Salt Spray & Corrosion Testing
For springs exposed to harsh environments, we verify coating quality and corrosion resistance through standardized testing protocols.
- Zinc plating verification
- Phosphate coating adhesion
- E-coating durability assessment
- Stainless steel passivation check
Inspection Reports & Documentation
Complete traceability from material to shipment. Every measurement recorded, every batch tracked.
What gets measured gets controlled — and documented.
Before Shipment Inspection
Final verification before any order leaves our facility.
Random Sampling
Statistical sample check per batch
Visual Defects
Surface & finish inspection
Quantity Check
Count verification vs PO
Packaging
Protection & labeling review
No shipment leaves our factory without final approval from our QC team.
Quality Control ≠ Zero Defect
We don't promise zero defect manufacturing. No one honestly can.
What we promise: controlled processes, measurable quality, and corrective actions when deviations occur.
Real quality comes from process control and continuous improvement — not unrealistic claims.
Need Inspection Standards Tailored to Your Project?
Let's discuss your quality requirements and define the right testing protocol for your springs.