They’re right in front of our eyes most of the time and we see right through them: we’re talking about windscreens, of course. We rely on them for safe driving everyday, but do we ever stop to think, how is this windscreen made and why is it made this way?
We get it, it’s not the most pressing question on everyone’s mind, but you’d be surprised to hear the amount of thought and consideration that’s gone into making your windscreen safe, effective, and sleek. So, why is it so important to have a windscreen on our cars?
Why Do Windscreens Exist?
Have you ever gone for a run only to encounter getting an insect to the face (or worse, mouth)? It’s not a fun experience. And that’s only travelling at just over 10 km/h for most people. Imagine going faster – like a lot faster. Those that have had the pleasure of long road trips know the fun of cleaning small bugs off their car, particularly off the windscreen. And you guessed it, that’s what the windscreen serves to do: shield us from nasties. Windscreens protect us from any other external debris, pollution, weather conditions, and even UV rays. Not only this, but they are aerodynamically designed to not be met with wind resistance while travelling at high speeds.
So, windscreens serve a pretty important purpose for our safety. You’ll especially know this if you’ve ever encountered a cracked windscreen. It can be a shock receiving a sudden crack in your windscreen, but just know that without one, that scene would have been a lot more dire. So yes, while it can be annoying to have to replace a broken windscreen, it’s also very important.
Fun fact: over 1 million windscreens are replaced each year in Australia. That’s a lot of harmful debris that’s been shielded from us by our windscreen.
Credit: Robert Couse-Baker
Windscreen Safety Standards
Ok, so we know how important it is to have a windscreen, but did you know you can’t just slap on any piece of glass in front of your car and call it a day? The manufacturing and installation process of a windscreen has been fine-tuned over the years to meet exceptional safety standards across the world. In Australia, windscreens must meet the Australian Vehicle Standards. Further, all vehicles are evaluated using the ANCAP Safety Rating. The Vehicle Standards outline a few protocols Australian vehicles manufacturers must obey (outlined below), and ANCAP provide star ratings that indicate the level of safety a vehicle provides for its occupants.
Australian Standards for Windscreens
- Windscreens must be made from safety glass. This is because this safety glass is dual layered, with a chemical compound or laminated material separating both layers. When the glass breaks or shatters, the plastic centre holds the glass intact. Tempered glass is also often used for windows. This glass is stronger than normal glass due to chemical treatments. When tempered glass breaks its pieces don’t fall as readily.
- The glazing products in windscreens must also be sufficiently resistant to: incidents likely to occur in normal day-to-day traffic, atmospheric and temperature changes, chemical exposure, abrasion and combustion.
- Window tinting is permitted to have a Visual Light Transmission of no less than 35%. This, however, only applies to the windows – a windscreen must not be tinted completely (only it’s visor trip may be tinted).
- The windscreen should be able to pass a number of tests, such as the: ball impact test, fragmentation test, and tests of resistance to the environment, abrasion, high temperatures, radiation, humidity, weathering, and more.
Image sourced from: Pixabay
Windscreen safety is serious business, so it’s no wonder why the Australian Government takes precautions to ensure every windscreen is made to meet stringent standards. In addition to the windscreen itself being of high quality manufacturing standard, the process of installing, repairing, or replacing a windscreen must be conducted with the precise technique, resources, and tools.
At Novus, we take pride in using the most modern and safe methods of windscreen repair and replacement. As the inventors of windscreen repair in 1972, we’ve invested years of research and development, and testing to improve our process and make it the best in the business. We’re so confident in our services that we provide a lifetime guarantee on our glass replacement services. Trust Novus next time you’re in need of a windscreen repair or replacement, or read about what else we can do for you.
Now onto the nitty gritty – the actual manufacturing of the windscreen. This section gets a bit technical, but it’s important in the overall development of our trusted windscreens. Read on to learn more about how exactly we get from sand and raw materials to a fully installed windscreen.
How Autoglass is Manufactured
From raw materials to glass
The glass manufacturing process starts with combining the right combination and amounts of certain materials together with heat. These materials include silica (SiO2), sodium oxide (Na2O), and calcium oxide (CaO). These materials are derived from raw materials such as sand, soda ash (Na2CO3), and limestone (CaCO3). As these substances are weighed to a precise measurement, broken waste glass can also be added to the mixture. This is glass that has been processed through a recycling centre.
Once the materials are combined, the mixture is then heated into a molten state and processed using a float glass manufacturing process: molten glass floats to the top of the float chamber, rising above molten tin which keeps the glass flat and pushes it along like a conveyor belt (the high temperature of the chamber also cleans out impurities in the glass). As the glass cools while moving towards the exit of the chamber, it moves towards a specific furnace, called the lehr (any solar coatings are added before this process). Once in lehr, the glass is cooled gradually until it becomes hard and room temperature. Now the glass is ready for cutting.
Image sourced from: Pixabay
Cut to fit perfectly
Once the autoglass is cool and hard enough to measure, the cutting begins. Most manufacturers use a sharp metal point containing diamond dust to cut through the glass. All the cutting is performed by a number of specialty robots with the measurements programmed into their system. This system is usually automated and is monitored by cameras or optoelectronic measuring systems. After cutting it to size, the glass is then placed back in a furnace where it is heated (850 degrees celsius) to a point where it can be moulded into the desired shape.
After the shaping is complete, it is then blasted with large amounts of cold air. This is so it retains its hardness and shape. With the cold air reaching through it, this then creates a toughness in the glass to stop it from shattering. It also allows good vision through the windscreen.
Laminated for Safety
After the glass is cleaned, the next step is to laminate. It should be noted that sometimes the glass is laminated prior to being shaped. The lamination process is done using plastic moldings inside two layers of glass. The plastic moldings adhere to the glass through heat and pressure. Layers of approx. 0.3 inches are added gradually while the interlayer is approx. 0.98 inches. Altogether there are three separate layers: a glass layer, a plastic interlayer, followed by another glass layer. These layers are held together like a sandwich to support the vehicle and passengers should the car be in an accident. Once the layers are set, it’s time to test the windscreens using some of the aforementioned windscreen testing methods. Should the windscreens pass with flying colours (or weighted balls in this case), then the glass is exported for installation.
Installed and Ready to Go
Windscreens are typically added in the vehicle manufacturing process; however, sometimes they are installed as a result of a replacement. In the case of a replacement, the windscreen is ordered for your car from either the insurance company, a repair company, or by you. After the windscreen has arrived, the specialist will then either visit your house or get you to pop into a shop for the service.
Firstly, great care is taken in removing the old windscreen. This removal process includes all trim around glass, rear view mirror, wipers and the cowling that hold the windscreen in place. This is an important step to make sure no glass is exposed to sharp edges. Then, large suction caps are used to hold the old windscreen in place. An extractor and cold knife is used to cut out the urethane. Urethane is a glazing product that is used like glue to hold a windscreen into place, in compliance with Australian standards. After this the old windscreen is free from the car, it’s then placed onto the back of a glazier truck, held in by brackets.
To prepare for the new windscreen to take its place, a new molding spray along with glass cleaner is used to scrub the excess urethane off. This needs a little time to dry before the next step, which is priming the windscreen area for the new urethane. The pinchweld is primed along the glue line, as is the the metal of the car. This priming is to ensure that all scratches made from scrubbing out old urethane and windscreen don’t begin to rust.
After the primer is dry and the windscreen area has been prepped, the urethane is added and the new windscreen is then set into place. At this stage, rubber gloves are used to ensure fingerprints or marks don’t contaminate the windscreen. The windscreen is then pushed into the glue (urethane) line. After the windscreen is set, the wipers, cowling and mirror are re-installed.
Finally, a layer of window cleaner is sprayed over the windscreen and wiped down with proper glass cloth for a clean finish.
Image sourced from: Pxhere
What happens to the old windscreen?
While the world has developed an impressive process for making incredibly resilient and strong safety glass for vehicles, this glass isn’t the easiest to recycle. Normal glass without any laminate already takes millions of years to breakdown itself; however, there is a process for recycling normal glassware. Ultimately, adding that interlayer of laminate to glass threw a spanner in the works (pardon the pun) for many recycling companies. While this added layer provided protection should the unimaginable happen, it didn’t separate well from the surrounding glass. Yet, allowing all of our waste windscreen glass to enter landfills was also not a viable option, particularly as corporations began moving towards more sustainable processes. Thankfully, a new technique has been established that separates the laminate in windscreens from glass. The end product of this process is clean pulverised glass that is recyclable, and a layer of laminate which has also been repurposed. The use of this glass waste is so versatile that it is used in many everyday materials: from asphalt and concrete, to fibreglass.
To Wrap Things Up
Windscreens are a vital piece of a vehicle’s construction. They protect us from weather conditions, dust, dirt, and icky insects. In Australia, we have some of the toughest standards when it comes to windscreen manufacturing, ensuring our safety is the number one priority. Next time you’re driving in your car, take a second to truly appreciate the well-crafted glass that is your windscreen.
If your windscreen has seen better days, it may be time for an upgrade. You know you’re in the right hands with our windscreen specialists at Novus Autoglass. Contact Novus today for more information about their quality products and services.