Glass production
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How glass is produced


Glass is one of the oldest materials ever and it has a 9000 year old history. It is unknown, when it has been produced for the very first time. The oldest findings date back in Stone Age. Today, you possibly couldn´t imagine your daily life without glass.

Did you ever suppose, that in Bonn, an one-time german federal capital, a glass factory was standing, in which the worldwide known WECK jars were produced? After the loss of 3 glass factories - on account of the war - in Cottbus and Görlitz, the WECK depot in the Rheinland was moved to the Bonner suburban Duisdorf. There, it was remodelled to a glass factory. At this place, since 1950, container glasses for the industry and preserving glasses for householdings were produced.  About 1 million jars were produced every day. Marmalade & honey-jars, pickles & fruit jars. 365 days per year in a 4-shift-operation. Because glass melter couldn´t turned off easily. There was no way that they would be turned off just for the weekend or holidays. The production was working around the clock.

From nature

Glass is produced from a natural, inorganic virgin material, which is mostly unlimited presented in nature. So the materials were very close by for the WECK glass factory. Quartz sand, which is 70% of the virgin material, is made in Frechen, western part of Cologne. The chalk, which is 10% of the virgin material, is made in the close Eifel and the Soda (13%) stems from the Ruhr district. Regionality and short ways are also important for producing glass. With all these materials, glass can be made.

Glass can be recycled for 100%. Out of the recycled glass, new ones are produced. Each barrel of old recycled glass, saves energy, CO2 and virgin materials.

How to produce tulip jars
WECK® Tulip Jar

The exact ingredients, together with the fine shredded pieces of broken glass, go to a glass melting tank. This one is heated up at 1200 degrees. Within the temperature, the ingredients melt together to molten glass. Now, the temperature is rising again to 1400-1600 degrees.

From the glass melting tank, the liquid glasses get to a so called Feeder. In the Feeder, single glass drops are exactly detached and fall into the moulding machine. The little tulip jar is right now red-hot and 500-550 degrees hot. The jars are on an automatic band conveyor in the direction of a lehr, which cools down the jars every 30-100 minutes to 110 degrees. But it depends on size and wall-thickness, how fast they will cool down.

This time-consuming process is very important for the stability of the jar, so that no residual voltage lays on the glass, which could lead to glass brakes. The little tulip jar is now on it´s way to it´s quality check: high modern appliances, which are checking the quality of each jar.

Are there any streaks on the glass, little bubbles or inclusions? Can the glass resist a special pressure?

If there are even smallest mistakes, the jars are automatically sort out to a pile of shredded glass pieces and it will be melted down. So they are getting a second chance. The permanent controls throughout the whole process guarantees you a perfect quality of your jars.