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Type of Defect: |
Black Speck (1/3) |
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Description: |
Contamination of Organic substances |
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Observation Method: |
Visible by the human eye |
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Recommendation Upon Observation: |
Better visibility using a Magnifier (under polarized light / observed with small optical stress) |
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Other Evaluation Method: |
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Cause |
Countermeasure |
| Contamination of airborne dirt |
Keep cleanness of the material hopper |
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Contamination of airborne dirt |
Purge the cylinder |
| Contamination of airborne dirt |
Use proper material handling procedure |
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Degraded material from spaces and/or cracks on the sealing surfaces of the plasticizing unit |
Check the shut-off nozzle |
