How Are Windshields Manufactured?
We don’t really think much about car windshields – which is remarkable, considering how important a job they do for us! Let’s look into the fascinating world of windshield manufacturing and look at the problems the manufacturers have to tackle.
The materials required to make a windshield
The key ingredients to make windshield glass are soda ash, silica sand, limestone, dolomite and cullet. There are little quantities and traces of aluminum oxide and potassium oxide also included most of the time.
Silica is the major ingredient and around 65-70% of the windshield glass is just silica. This is what makes glass. After silica, soda ash is added to the mixture when silica is being heated. It decreases the melting point of the mix. Dolomite makes the mixture easier to work with, whereas limestone increases the efficiency of the glass and gives it a good finish. Limestone is also a key ingredient for making the glass more durable.
Then some water is poured into the mixture and heated at a specific temperature. All these chemicals and materials being blended and heated together give birth to glass.
How the windshield comes to form
We know that the glass is a major component but there are other things as well such as the wipers and its frame. The frame is really important for the windshield as it will support it while being fitted into a car or any other automobile. Laminated glass is what makes the windshield a sturdy and resistant material. The windshield is also tested to see how it performs in collisions and direct hits.
Despite it looking like any other glass to the eye, laminated glass is much stronger because it has 3 layers. The core or the middle layer is made of poly-vinyl butyral while tempered glass on both the sides sandwiches it. This reinforcement process has been proven effective and safe. Small objects like stones or debris etc can’t do any major damage to the windshield which they normally could do to regular glass. Although it is made to be quite durable, there are some times that a windshield needs to be replaced due to an accident or something really heavy breaking the glass. But for normal use, the windshield is quite strong and can withstand wear and tear.
The majority of the windshield glasses are made using the ‘Float method’. The method is called the float method because the glass is actually made by making it float in a tank.
The ingredients for the glass are mixed with water and are heated in a tank. Then the mixture is kept in a chamber where the glass mixture floats. The chamber has a strip of thin tin and the mixture floats upon it.
After the glass is cooled, it is then shaped according to the design of the car; the frames are added to it so that it fits. It is fairly easy to shape because every model has its own template.
The windshield is now ready to be installed in the car.