At Nam Vang Ha Nam JSC, quality isn’t just a buzzword—it’s our promise. From raw material sourcing to final inspection, our comprehensive quality control process ensures that each batch of recycled polyester staple fiber (rPSF) adheres to strict international standards for safety, durability, performance, and sustainability.

Our Testing Process: Quality at Every Step

Using both standardized testing procedures and our in-house quality checks, we guarantee that our recycled fibers meet global industry standards. The following outlines our step-by-step quality control process, integrated with sample testing:

1. Material Testing and Sampling Process

The first stage of quality control begins with material inspection upon receipt of PET flakes from import containers:

• Sourcing Verification: We source plastic waste from certified suppliers who comply with sustainable and ethical recycling practices. Each batch of raw material must have traceability documentation to ensure compliance with the Global Recycled Standard (GRS).
• Initial Screening: PET flake samples are taken directly from each container for testing. These samples are prepared for testing, where they undergo a series of assessments, including drying, contamination checks, and resilience tests.
• Drying Process: The samples are placed in a dryer to remove moisture. Ensuring the right moisture content is critical for accurate testing.

2. Contamination Check

Once the drying process is complete, the samples are thoroughly checked for contamination:

• PVC and Other Contaminants Testing: A sheet is used to weigh any PVC or other contaminants present in the sample. Contamination in PET flakes can lead to defects in the final fiber product, so this step ensures the purity of raw materials.
• Data Summarization: After contamination checks, the data is summarized, and if any issues are detected, they are communicated back to the supplier for corrective actions.

3. Fiber Production and In-Line Testing

As the PET flakes pass quality checks, they are melted and extruded into fibers. In-line testing is conducted at various points during the production process:

• Denier and Cut Length Control: Automated systems regulate the fiber thickness (denier) and cut length, ensuring consistency in the final product.
• Moisture Testing: The fibers are tested before and after the drying process using an oven to ensure that moisture levels meet the specified standards (typically, 45 minutes in the oven for accurate readings).

4. Post-Production Sample Testing

After production, fibers undergo further testing to confirm their quality:

• Resiliency Test: Fibers are tested for resilience using the V1/V2/V3 method, which requires specific amounts of fiber and precise equipment, including a test tube, oven, and scales. This ensures that the fibers can withstand stretching and maintain their shape.
• Crimp Testing: The crimp count (4-8 crimps per inch for 7D fibers and 4-6 crimps per inch for 15D fibers) is assessed. Crimping gives fibers elasticity and softness, essential for their end-use applications.

5. Oil Pick-Up Rate (OPU) Testing

One of the key performance indicators of polyester staple fibers is their oil pick-up rate (OPU), which affects the fiber’s processing in downstream applications like spinning and knitting:

• Oil Separation Test: This involves placing 2 grams of fiber in a tube and adding a specific amount of chemical ETH over a series of timed intervals. The mixture is then processed in an oil-separating machine at 115°C. The oil is collected in a dish, and the OPU is calculated using the formula: OPU​=(Mg×100)/2
• Fibers are tested to meet the standard minimum OPU of 0.27% for 7D and 15D HCS fibers and 0.26% for 7D and 15D HCD fibers.

6. Compliance with Certifications

Nam Vang Ha Nam ensures that all products comply with global certifications:

• GRS and OEKO-TEX® Compliance: Every batch is tested for compliance with the Global Recycled Standard (GRS) and OEKO-TEX® standards to guarantee that our recycled fibers meet environmental, safety, and sustainability benchmarks.

7. Final Inspection and Packaging

Before shipment, fibers undergo a final inspection:

• Visual Inspection: Each bale of fibers is checked for visible defects such as uneven cuts, contaminants, or any other inconsistencies.
• Weight Check: The final bales are weighed and inspected for proper sealing to ensure the integrity of the fibers during transit and storage.

8. Documentation and Reporting

All test results and findings are meticulously documented:

• Reporting to Suppliers: If any discrepancies or contamination are found, a detailed report is sent to the suppliers for rectifications.
• Record Keeping: All test data and documents are archived for future reference and traceability, ensuring continuous improvement in our quality control process.