Their special scenarios demand strict quality control.

Many buyers ask for simple ways to judge their quality.

We list 6 practical inspection methods below.

Standard: Flash height ≥1.0mm from the key surface.

The flash must hide after installing the shell.

Use a vernier caliper to measure directly.

Standard: Positioning hole burr ≤0.1mm; edge burr ≤0.5mm.

Excessive burrs harm assembly and usage.

Standard: No cracks affecting use; small cracks ≤1.0mm are allowed.

Measure cracks with a vernier caliper.

Standard: No color exposure after vulcanization and assembly.

No obvious color difference vs the standard sample.

Use natural light or 40W fluorescent lamp for check.

Professional inspectors (vision ≥1.0, no color blindness) check at 30cm for 5 seconds.

Standard: Elastic wall thickness ＜0.1mm → X=20%;

≤0.2mm → X=15%;

＜0.3mm → X=8%.

Test with a thickness gauge.

Standard: No visible spots or bumps on exposed parts after assembly.

Inspect visually for 5 seconds at 30cm under 40W fluorescent lamp.

They meet food & drug grade standards with no harmful substances.

They work from -60℃ to 180℃ and resist 135℃ steam or 180℃ hot air sterilization.

Safety factor ≥3 times working pressure.

They comply with FDA and European Pharmacopoeia standards.