Quality Control Testing Standards for Heat Shrink Tubing
At Haosheng New Material, every batch of PET and PVC heat shrink tubing undergoes comprehensive quality control testing before shipment. Understanding these standards helps verify product reliability and compliance.
1. Shrink Ratio Verification
Test method: Samples heated to specified shrink temperature; recovered inner diameter measured.
Acceptance criteria: Recovered ID must meet minimum shrink ratio (typically 2:1). A 10mm pre-shrink ID must achieve recovered ID of 5mm or less.
2. Wall Thickness Measurement
Test method: After full shrinkage, wall thickness measured at multiple points using micrometer.
Acceptance criteria: Wall thickness within specified tolerance range (e.g., 0.08–0.15mm for PET). Consistency across tube length is critical.
3. Flame Retardancy Test (UL94)
Test method: Vertical burn testing per UL94 standards. Flame applied for 10 seconds, removed, then reapplied.
V-0 acceptance criteria:
- Burning stops within 10 seconds after flame removal
- Total flaming combustion under 50 seconds for 5 samples
- No flaming drips igniting cotton below
- No afterglow lasting over 30 seconds
4. Dielectric Strength Test
Test method: Progressive voltage increase across tube wall until breakdown, per IEC 60243-1.
Acceptance criteria: PET >15 kV/mm; PVC >10 kV/mm.
5. Thermal Aging Test
Test method: Samples in aging oven at 135°C for 4 hours per IECQ standards, then tested.
Acceptance criteria: After aging, retain minimum 70% tensile strength and elongation; no cracking or degradation; dielectric strength within limits.
6. Reflow Soldering Compatibility
Test method: Tubing subjected to 260°C peak temperature reflow conditions.
Acceptance criteria: No melting, cracking, or separation. Tube must maintain full capacitor body coverage.
Our QC Commitment
Haosheng maintains ISO 9001 certified quality management across all three factories. Every order includes quality inspection reports. Third-party testing (SGS, Intertek) available upon request.