√ Chemical composition testing: Using equipment such as a spectrometer to detect the content of elements like C, Si, and Mn in the steel, ensuring compliance with material with a deviation not exceeding ±0.03%.

√ Mechanical property testing: conduct tensile tests, torsion tests, bending tests, etc., to determine tensile strength, yield strength, elongation, etc., and evaluate the materials plastic deformation capability and surface quality.

√ Surface defect screening: Using eddy current testing, optical inspection, and other technologies to check for defects such as cracks, scratches, and pits on the material surface, with a capable of detecting cracks as shallow as 0.1mm.

√ Winding process control: The CNC spring machine monitors parameters such as wire feeding speed, winding angle, and pitch accuracy in real time to ensure consistent spring geometric with the mean diameter tolerance controlled within ±0.05mm.

√ Automatic detection control: Proprietary patent [Lifeng Spring Automatic Detection Control System Copyright] 24/7 automated monitoring of spring dimensions, elasticity,, and appearance defects, integrating PLC control, data acquisition, automatic judgment, and defective product sorting functions.

√ Heat treatment process monitoring: temperature uniformity controlled within ±5℃; atmosphere protection to prevent decarburization; oxygen content maintained below 0.1%; temperature monitoring system ensures the time-temperature curve meets process requirements; elastic limit fluctuation less than 3%.

√ Surface treatment monitoring: Electroplating layer thickness is sampled every 2 hours with a fluctuation range of ±2μm; salt spray test after passivation treatment verifies corrosion to ensure no red rust for 72 hours.

√ Automatic dimension detection: Laser diameter gauge monitors wire diameter changes in real time with an accuracy of 0.005mm; CCD image measurement system detects parameters such outer diameter and pitch, with a detection frequency of 10 pieces/minute.

√ Rapid mechanical property testing: The automatic spring testing machine samples and tests the force value characteristics every 10 pieces, with data uploaded to the MES system in real time, force value consistency by 60%.

√ Visual inspection: High-speed cameras inspect surface defects with a resolution of 0.02mm; AI image recognition technology automatically classifies defect types, with false positive rate of less than 0.5%.

√ Mechanical property testing: Use a spring tension-compression testing machine to detect indicators such as load, stiffness, and permanent deformation to ensure compliance with design requirements, with load deviation controlled within ±1%.

√ Fatigue life test: Accelerated life testing simulates actual working conditions, with the number of cycles reaching the design requirements and the failure probability below 0.001

√ Environmental adaptability testing: Salt spray test verifies corrosion resistance, with no substrate corrosion after 500 hours; high and low temperature cycling test (-40 to  120°C) checks temperature stability, with performance change less than 2%.

√ Process capability index monitoring: CPK values are statistically analyzed monthly, critical characteristics are maintained above 1.67, control charts analyze process stability, and X- charts identify abnormal fluctuations.

√ Quality traceability system: Batch management records raw materials, processes, and test data, with a 10-year retention period; QR code identification enables unitlevel traceability, and query time is less than 3 seconds.