The inspection certificate for glass bottles is based on several key standards, typically evaluated through five main criteria:
- Deformation of the Bottle Body: Bottles may deform if they haven’t fully set in the forming mold. High material and action temperatures can cause sagging, particularly if the upper part is too heavy. Additionally, if the bottle’s bottom hasn’t cooled adequately, it may show marks from the conveyor belt.
- Material Marks: Material marks are one of the most common defects, often visible only under reflective light. These can occur on the bottle’s neck, shoulders, and base, primarily due to fluctuations in furnace temperature during production.
- Thickness Irregularities: If the temperature of the glass material isn’t consistent during processing, thinner areas can form where the material is too hot, while cooler areas may be thicker. Uneven mold temperatures can also lead to this issue, with slower cooling resulting in thin sections.
- Cracks: Cracks may appear in various forms, including wrinkles or fine lines. They often result from excessively cold material drops, prolonged drop lengths, or misalignment during molding.
- Bubbles: Bubbles can form during shaping, appearing as large or clustered small bubbles. These differ from small air pockets uniformly distributed in the glass, indicating a potential issue with material mixing or heating.
By adhering to these standards, manufacturers can ensure the quality and safety of their glass bottles, contributing to their compliance in the market.