Quality Control Report for Primed-Coated MDF Wood Moldings

Quality Control Report for Primed-Coated MDF Wood Moldings

Product Name: Primed-Coated Medium-Density Fiberboard (MDF) Wood Moldings
Production Batch: XXXXXX
Production Date: XX/XX/XXXX
Origin: China (XX Province, XX City)
Export Destinations: United States, Canada
Sampling Quantity: XXX pieces (5% of total batch quantity)
Overall Pass Rate: 99.2% (based on comprehensive evaluation of all test items)


1. Inspection Criteria

  • Chinese Standards: GB/T 11718-2021 (MDF), GB 18580-2017 (Formaldehyde Emission Limits).
  • U.S. Standards: ASTM D1037-2020 (Wood-Based Fiberboard Testing), CARB Phase II (Formaldehyde ≤0.05 ppm).
  • Canadian Standards: CSA O437-2020 (Wood-Based Composite Panels), CAN/ULC-S102.2 (Surface Burning Characteristics).
  • Environmental Regulations: U.S. EPA TSCA Title VI, Canada SOR/2016-176 (Formaldehyde Emission Limits for Composite Wood Products).

2. Appearance Quality Defects and Pass Rates

Surface Flatness

  • Surface Cracks: Detected via visual inspection and 20X magnification. Cracks exceeding 5 mm in length or 0.2 mm in width were deemed defective. Two samples exhibited minor cracks (≤3 mm), resulting in a pass rate of 99.6%.
  • Unevenness: Measured using a straightedge and feeler gauge. Local depressions or protrusions ≥0.5 mm in height were considered non-compliant. Three samples showed minor fluctuations (0.3–0.4 mm), yielding a pass rate of 99.1%.
  • Blisters/Delamination: Identified through visual checks and manual peeling tests. One sample displayed edge delamination (<1 cm²), repaired to achieve a 100% pass rate.

Coating Uniformity

  • Coating Peeling: Evaluated via cross-cut adhesion test (1 mm × 1 mm grid). Peeling ≥5% was rejected. All samples achieved Grade 0 (no peeling), with a 100% pass rate.
  • Sagging/Over-Application: Coating thickness was measured using a digital thickness gauge. Nominal thickness: 2.0 mm (±0.3 mm). Two samples exceeded tolerance (2.4 mm), resulting in a 99.3% pass rate.
  • Color Deviation: Compared to standard color swatches using a spectrophotometer (ΔE ≥1.5 = defective). ΔE values ranged from 0.8 to 1.2, achieving a 100% pass rate.

Edge and End Integrity

  • Burrs/Chip-Outs: Edge roughness (Ra) was measured with a profilometer. Ra ≥6.3 μm was rejected. Five samples showed Ra values of 5.8–6.1 μm, yielding a 99.5% pass rate.
  • End Cracks: Inspected under a magnifying glass. Cracks ≥3 mm were rejected. No defects found (100% pass rate).

Contamination and Foreign Matter

  • Stains: Tested with alcohol wipes. One sample retained an irremovable glue residue (99.8% pass rate).
  • Embedded Debris: X-ray scanning detected one sample with trace sand particles (<0.2 mm diameter), achieving a 99.8% pass rate.

Biological Defects

  • Mold Spots: No mold growth observed after 7-day incubation (28°C, 85% RH). Pass rate: 100%.
  • Insect Holes: No insect damage detected via full-surface magnification. Pass rate: 100%.

3. Internal Quality Defects and Pass Rates

Physical Properties

  • Moisture Content: Oven-dry method (105°C) showed an average of 10.2% (limit ≤12%). Pass rate: 100%.
  • Modulus of Rupture (MOR): Three-point bending test (200 mm span, 5 mm/min loading) yielded a minimum MOR of 18.5 MPa (standard ≥15 MPa). Pass rate: 100%.
  • Bond Strength: Universal testing machine measured an average of 1.2 MPa (standard ≥0.8 MPa). Pass rate: 100%.

Environmental Performance

  • Formaldehyde Emission: 1m³ climate chamber method (23°C, 50% RH) showed 0.03 ppm (CARB Phase II limit: 0.05 ppm). Pass rate: 100%.
  • VOC Emissions: GC-MS analysis confirmed total VOCs at 0.3 mg/m³ (limit ≤0.5 mg/m³). Pass rate: 100%.
  • Heavy Metals: XRF analysis detected no lead, cadmium, or other restricted metals (compliant with U.S. CPSIA and Canada CCPSA). Pass rate: 100%.

Coating Durability

  • Abrasion Resistance: Taber abrasion test (500 cycles, 1 kg load) resulted in 0.05 g average wear (limit ≤0.1 g). Pass rate: 100%.
  • Heat-Humidity Resistance: No wrinkling or cracking after 48 hours at 70°C/95% RH. Pass rate: 100%.

Dimensional Stability

  • Linear Expansion Rate: Length change was 0.25% (limit ≤0.3%) when humidity increased from 30% to 90%. Pass rate: 100%.

4. Functional Performance and Pass Rates

Installation Compatibility

  • Joint Gaps: Post-installation gaps measured ≤0.4 mm (limit ≤0.5 mm). Pass rate: 100%.
  • Screw Holding Capacity: Minimum pull-out force was 65 N (standard ≥50 N). Pass rate: 100%.

Fire Resistance

  • Flame Spread Index: ASTM E84 vertical burn test showed a flame spread index of 15 (limit ≤25). Pass rate: 100%.

5. Non-Conformance Handling

  • Critical Defects (Category A): No formaldehyde overlimits or structural cracks detected.
  • Major Defects (Category B): Three samples with surface unevenness and two with coating thickness deviations were reworked and re-inspected.
  • Minor Defects (Category C): One sample with minor stains was approved by the customer under concession.

6. Conclusion

This batch of putty-coated MDF wood moldings complies with Chinese GB/T 11718, U.S. ASTM D1037, and Canadian CSA O437 standards. Environmental performance meets CARB Phase II, EPA TSCA Title VI, and Canada SOR/2016-176 requirements. With an overall pass rate of 99.2%, the batch is approved for export to the U.S. and Canadian markets.

Quality Control Manager: XXX
Report Date: XX/XX/XXXX


Appendix

  1. Test Data: Detailed records of 12 physical performance parameters (e.g., MOR, moisture content).
  2. Certifications: CARB Phase II, EPA TSCA Title VI, FSC, and Canada ISPM15 (wood packaging compliance).
  3. Customer Approval: Signed concession agreement for minor defects.

Note: This report is based on statistical sampling. Continuous monitoring of critical parameters (e.g., formaldehyde, moisture content) and retained samples are recommended for batch traceability.

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