In the production of glass bottles, several critical factors and inspections determine the quality and qualification of the final product. Once the bottles come off the production line, an initial visual inspection is conducted by the workers to assess their general condition. After undergoing a period of annealing, the workshop supervisor conducts a more thorough examination. The common issues encountered during this process include:

Bottle Deformation: Deformation typically occurs when the glass droplet temperature and the working temperature are too high before the bottle is fully formed in the mold. This can cause the bottle to collapse or become misshapen. If the upper part of the bottle is too heavy, it can lead to similar problems. Additionally, if the bottle’s bottom has not sufficiently cooled, it may pick up pattern marks from the conveyor belt, resulting in an uneven base.

Material Channel Marks: As identified by glass bottle manufacturers, material channel marks are a prevalent defect. These marks, which are often very fine and visible only under reflected light, commonly appear around the mouth, neck, and shoulder of the bottle, as well as on its body and bottom. This defect is usually caused by fluctuations in furnace temperature.

Uneven Thickness: Uneven thickness in glass bottles is a result of temperature inconsistencies in the glass material droplet. Higher temperatures reduce viscosity, causing the glass to be blown thinner, while lower temperatures increase resistance, leading to thicker areas. Additionally, if the mold temperature is uneven, the side with a higher temperature cools slowly and becomes thinner, whereas the side with a lower temperature cools faster and becomes thicker.

Cracks: Cracks can manifest in various forms, including creases and numerous fine wrinkles. These occur primarily when the glass droplet is too cold, too elongated, or does not land centrally in the initial mold, causing it to stick to the mold cavity wall.

Bubbles: Bubbles that form during the manufacturing process can appear as either several large bubbles or a cluster of small bubbles. These are different from the uniformly distributed small bubbles that naturally occur within the glass itself.