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2023-02-01
Details of glass bottle production process
1- Melting the raw materials of glass bottles in the furnace
The raw material and broken glass are continuously melted at high temperature, around 1650°C. The furnace runs 24 hours a day and the raw material mixture forms molten glass in about 24 hours. The molten glass passes through the forehearth and then at the end of the forehearth, the glass stream is cut into pieces according to the weight and the temperature is set precisely.
2- Glass bottle/jar forming
Two forming methods are applicable: press-blowing or blowing, performed in the IS machine.
Press-blown glass bottles
The cut drops fall and are pressed into a blank mold with a metal plunger, where it expects the shape of the mold, which is then called the profile blank. Next, the blanks are moved into the final mold and blown into the mold for final measurements. This process is typically used for wide-mouth glass bottles, but can also be used to produce fine necked glass bottles.
Blowing Glass Bottles
Cut drops of material fall and are compressed into the blank mold in blow blow molding. The drops are pushed into place using compressed air, called a profile blank, and moved to the final mold to be blown again to form the inside of the framed glass bottle. Glass bottles with different neck thicknesses (narrow containers) can be manufactured using a blow-blow arrangement.
3-Annealing in the glass bottle manufacturing process
Regardless of the process, blown glass containers are usually surface coated after they are formed.
While they are still hot, in order to make the bottles and jars more scratch resistant, this is called hot end surface treatment, and then the glass bottles are taken to an annealing furnace where their temperature returns to about 815 °C and then decreases gradually to below 480 °C. This will take about 2 hours. This reheating and slow cooling removes the pressure from the container. This enhances the robustness of the naturally occurring glass containers. Otherwise, the glass can easily break.
4 - Quality Inspection of Glass Bottles
Prior to inspection, they are usually surface coated on the cold end to reduce the temperature of the glass container to about 100°C. Otherwise, the glass is easily scratched.
After leaving the cold end of the annealing furnace, to ensure product quality, we use Led beam technology (Led inspection), Camara inspection machines, and integrated inspection machines to detect faults that are not visible to the naked eye. These include, but are not limited to: seal face inspection, dimensional analysis, wall thickness inspection, breakage detection, bottom side scan, and wall scan. Any non-compliant bottles will be automatically rejected and these rejected bottles will be re-melted and re-used as raw material. Automated inspection will ensure consistent quality for our customers.