Before glass bottle manufacturing starts, all raw materials including silica sand, soda ash, limestone and recycled glass (cullet) must first be combined, heated and melted at temperatures in excess of 1500°C before injecting this molten glass liquid into molds for shaping into bottles. There are three primary methods used in glass bottle forming:

1. Blowing: For this process, molten glass is dropped into a mold before air is blown through it to expand it and fill out its shape.

2. Press and Blow: Pressing glass molten into mold cavities before blowing air through to shape its edges is usually the preferred process, making press-and-blow the most popular choice among glass manufacturers.

3. Injection Blow Molding (IBM): For this technique, an empty hollow tube made out of molten glass called a parison is injected into a mold before being expanded and expanded back out again into bottle shape by blowing.

Once glass bottles have been formed, they must undergo annealing in an annealing lehr to mitigate internal stresses caused by transitioning from high temperatures to room temperatures – such as transition from high pressure heating systems. Slowly cooling these glass bottles helps alleviate internal stresses while strengthening them further. Before being packaged up for delivery to customers, all bottles undergo initial machine inspection for defects followed by secondary manual inspection to ensure only qualified bottles reach customers. Finally, our packaging team will pack these perfect bottles into boxes according to customer specifications, then load them onto pallets for transporting directly to their designated destination.

You can watch the following detailed and intuitive video about glass bottle manufacturing. This video provides a comprehensive overview of the various molding techniques used to shape molten glass in glass bottle molds, as well as the entire process from production to quality inspection to packaging.