How Are Windshields Made?

How Are Windshields Made?

Getting your windshield repaired is one thing; getting one replaced requires it to be ordered from the manufacturer. The goal; to ensure a perfect fit and driver safety. So, a question arises; how are windshields made?

Windshields were initially made of glass which got shattered easily. The next stage in the development of windshields saw the use of tempered glass which was much stronger and shatter-proof. However, it would also break into small pieces. The latest version of the windshield is considered to be the safest. It is made of multi-layered laminated glass that doesn’t injure the driver or passengers.

How Windshields Are Made

Modern windshields are made up of three layers. Two layers of glass and one cellulose layer between them. This glass is just as strong as tempered glass with additional capacity to bend upon impact.

  • It begins with silica, soda ash, limestone, dolomite and cullet being mixed together (with water). Once mixed, it is heated to 1450°C for chemical fusion.
  • The molten mixture is passed through the float chamber where it “floats” on a thin layer of molten tin.
  • The molten glass is then transported to another chamber called “the Lehr” where it cools down in a special furnace.
  • This raw glass is then cut into appropriate sizes with the help of scribes.
  • The glass is then shaped and tempered by placing the glass on a mold with a specific curvature. It is heated to help it take the mold’s shape and is then cooled rapidly. This makes the glass strong.
  • Finally, two layers of this tempered glass are taken and a thin layer of PVB or Poly-Vinyl Butyral is placed between them. The three layers fuse when heated in an autoclave.
  • The windshield is now ready to be fit onto the frame of the car and bonded with urethane.

Every windshield is made according to specific requirements of particular models.

Thanks for reading!