The following raw materials are subjected to tests before they are accepted for production:
- Aluminium Coil
- Plastic Granules (Used for LDPE and mineral core)
- Adhesive Film
- Protective Film
Aluminium Coil Tests:
- Physical Properties Test: This test is the most initial coil test and focues on the basics using visual inspections for damages, using a micorometer to measure thickness of coil and paint, checking the weight and ensuring the color is matched as per the client’s needs
- Dry Adhesion Test (ASTM D3359-02): Using cross hatch tool and 50mm width scotch tape, this test checks the quality of the paint.
- Wet Adhesion Test (ASTM D3359-08): Using the same cross hatch tools, the aluminium is then placed in distilled or de-ionized water at 380C for 24 hours. This test further ensures the quality of the paint
- Pencil Hardness Test (ASTM D3363-05): This test requires flat lead and the hardness tester to test the quality of the paint.
- Boiling Water Resistence (ASTM D3359-08): The coil sample is them submerged in boiling water for 2 hours.
- T-Bend Test (ASTM D4145-83): A sample coil is bend at 1800 several times.
- Solvent Resistence Test (ASTM D5402-06): Methyl Ethyl Ketone (MEK) is applied to the coil with a cloth so check is there is any color disfiguration.
- Impact test (ASTM D2794-93): Weight is dropped at a height using the impact tester tool and checks the strength of the pain and coil.
For the Above tests, the coil must be free of any bubbles, spots, peeling off, cracking, adhesive damage or color deviation. If the sample passes all the tests, the coil is accepted in the factory, if there are any quality problems, the coil is rejected and sent back to the supplier.
- Physical properties test: A sample is taken and is visually inspected to determine is the surface is smooth and soft to the touch under a shining light.
- Float test: Checks the density of the Granules.
- MFI Test (ASTM D-1238): Using a melting Index Apparatus, the LDPE sample is extruded.
- Fire Rated Tests: Using a Bunsen burner or blow torch, the granules for the Fire Retardant panels and burned to check their fire resistance and burn resistance. Depending on the grade, the sample can be burned for 90 minutes to ensure it matches the required quality.
- Physical Properties Test: Using a micrometer measuring tape, the thickness of the adhesive film is measured and a visual inspection determines that there is no moisture in the adhesive film.
- Adhesive Strength Test (ASTM 903-98): Using a strength check scale, the adhesive film is pulledto breaking point. The end result should be higher than 7 N/mm.
- Physical Properties Test: Using MEK solution and meter tape the protective film is checked for moisture, design and color strength.
- Oven Test: The sample is placed in a oven for 2hours at 80 degrees C. The final result should show the protective film without defects in terms of melting or detaching from the adhesive.
During Production Process (On Line Inspection)
- Pre Quality Checking for Production: Using the micro meter, measuring tape and color reader, the size, color and thickness are confirmed with the order.
- Line Quality Inspection Test: The product is consistenty check to make sure it meets all requirements. Any minor defect is immediately cut of and extracted from the production line.
- Peel Strength Test (ASTM D 1781-76): Using the push pull scale, every 30 minutes, a sample is removed from the production line and the skin is peeled off to measure the strength. Depending on the thickness of the coil, the strength should be appropriate.
After Production Inspection
The final test is done on the finished good to inspect the following:
- Dimensions are accurate with the production order
- No bubbles, ripples, waves or abrasions.
- Any improper surface is removed
- Ensure the horizontal level of the Panels is correct