In the realm of medical injection molding, the pursuit of impeccable quality is paramount. However, transparent, white, or light-colored plastic parts often encounter the vexing issue of surface contamination during production, which not only detracts from the product's aesthetic appeal but also leads to increased scrap rates, resource wastage, and escalated costs. To tackle this challenge, this article delves into the root causes of contamination and proposes targeted improvement strategies, aiming to assist medical injection molding enterprises in enhancing production efficiency and product quality.
Comprehensive Contamination Control: An Art of Management Across the Entire Chain
The appearance of black spots on the surface of medical injection molded parts is, in essence, a rigorous test of the entire production process management. From raw material handling to mold opening and closing, every step requires meticulous control to effectively reduce the occurrence of contamination. Below is a detailed exploration of the causes of contamination and corresponding improvement measures:
1. Residue from Raw Material Overheating
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Strategy: Regularly perform full ejection of residual material, thoroughly clean the barrel; lower the melt temperature to reduce decomposition; optimize the process to minimize residual material accumulation.
2. Raw Material Contamination and Cleanliness of Drying Hoppers
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Measures: Rigorously inspect raw material purity to ensure no black spots are mixed in; thoroughly clean drying hoppers to eliminate contamination sources.
3. Improper Handling of Heat-Sensitive Plastics
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Adjustments: For heat-sensitive materials, increase gate size to reduce injection pressure; simultaneously, slow down the injection speed to minimize overheating caused by rapid injection.
4. Defects in Barrel Design
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Inspection: Regularly check for wear on nozzles, non-return valves, and barrels, promptly replace worn parts or consider changing the machine to avoid dead spots that cause raw material overheating and decomposition.
5. Inadequate Environmental Control
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Improvements: Adjust the workshop fan configuration, shut off fans when necessary, and cover injection molding machines with film to effectively isolate airborne dust.
6. Uneven Pigment Dispersion
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Optimization: Increase the use of dispersants or choose higher-quality pigments to ensure even distribution of pigments in the plastic.
7. Contamination of Drying Hopper Air Intake
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Protection: Install dust covers on the air intake of drying hoppers to prevent external dust from entering.
8. Nozzle Issues
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Maintenance: Regularly clean nozzle holes to ensure unobstructed flow; for nozzles with excessively small diameters, appropriately enlarge them to improve melt flow.
9. Management of Sprue Waste
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Control: Strengthen the management of sprue waste, handle it in a dust-free environment to avoid secondary contamination.
10. Equipment Cleanliness
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Implementation: Regularly perform comprehensive cleaning of granulators and mixers to ensure the cleanliness of the production environment.
Conclusion
Resolving surface contamination in medical injection molding products requires not only technological advancements but also meticulous management of the entire production process. Through the comprehensive implementation of the aforementioned measures, the incidence of contamination can be effectively reduced, product qualification rates can be improved, and greater economic and social value can be created for enterprises. In the medical field, every minor improvement is a testament to respecting and enhancing the quality of life. Let us work together to contribute to the quality enhancement of the medical injection molding industry.