In the automotive industry, the glass surfaces on vehicles have increased in recent years. Thus, the glass has gone on to become a structural part of the vehicle, while continuing to fulfill its initial function of allowing visibility and isolate the cabin from outside.
Before focusing on the windshield repair it is extremely important to know the type of glass used in the automobile which is classified according to their functionality. The following are the main features of the most representative type of crystals.
Tempered Glass
It is composed of a single glass sheet of a thickness of 5mm, which is introduced into a furnace at a temperature between 500 and 750 ° C then is subjected to rapid cooling. This treatment is more durable and forms a rigid glass. Due to internal stresses in the glass caused by a rupture it occurs it is fragmented into many small pieces. For security reasons this glass is no longer used in windshields, settling on the side windows and rooftops (sunroof).
Laminated glass
Its configuration, sandwich type is comprised of two sheets of standard glass, joined together by a central sheet of clear plastic polyvinyl butyrin (PVB) or simply butyrin. For security reasons, this type of glass is required on windshields. In case of breakage, the polymer sheet glass remains in position, avoiding the risk of projection of glass particles or expulsion of the occupants, while enabling emergency vision to the driver.
Broken Windshield
Generally, breaking the windshield can be due to two causes, the impact of an object at high speed (pebbles, gravel, etc.) or the transmission of a stress or strain on the body itself.
The existence of damage caused by the impact depends on several factors: size of the object projected on the windshield, object material, speed and angle of impact. Here are the most common types of notches are indicated: Windshield repair is a process that combines technology and expertise to fill a damaged windshield with a transparent adhesive and resin (polymer) area. This resin (acrylic) is polymerized or cured by ultraviolet light of 365nm wavelength. With this technique, the damaged area of the windshield completely recovers its surface tension (structural strength) and almost 100% of its clarity.
Repair techniques
Crack formation. With the help of a punch crater were removed loose glass particles to facilitate penetration of the resin and prevent imperfections. Repair technique involves injecting the resin pressure inside the fracture. For this, specific nozzles are used by the injector holder proper, are fixed to glass, so that they are centered on the point of impact.
After removing the injector a special cellophane foil is placed on breakage. This causes the resin sheet dries quickly with a UV lamp, in a time of 5 to 10 minutes, dependent of the equipment and type of resin. Finally the resin need to be polished for transparency, for which you use the polishing liquid supplied with the equipment, which carries a fine abrasive aggregate, usually cerium oxide powder.
Fissures
To repair a crack is advisable to have a hole with the help of a drill to a distance of 3 mm in front of it or end to avoid spreading during the repair.
Put the nozzle on the hole made at the end of the crack and begin to inject the resin progressively, as if it were an infiltration. As the resin penetrates in breaking, placed plastic sheets impregnated with the same resin to prevent it from flying out. When the crack is completely filled with resin and is covered throughout its length with blades plastic can be cured with ultraviolet by allowing radiation for 10 minutes. Scrape the excess resin with the blade in a single direction. The repair will be complete with a polish and a final cleaning of the area.
It is critical that the owners not spend much time since the damage occurs. It will always be advisable to repair rather than change a damaged windshield while is safe and feasible, this because the original factory sealed windshield to the body is preserved. It is cheaper and faster so that the unit is functional in a few hours if not in minutes.
Today the incorporation of rain sensors, temperature, radio antennas, photo chromatic glass, security systems tech … have considerably add more expensive costs to windshield and here again the repair is a more affordable solution.
Repair quality
To repair windshields with satisfactory results is necessary to have professional equipment, experience in using them and a good knowledge of the best practices in the industry.
In the US, professional windshield repair benefits from a voluntary standard that establishes practices and procedures. This rule known as Automotive Repair of Laminated Glass Standard (ROLAGS) was approved in 2007 by the National Glass Association (NGA) and the National Windshield Repair, two professional associations of the glass industry.
Considerations
- Any repair to the area swept by the wiper should not reduce the effectiveness of the wipers, If after repair remain some residual point, it must not exceed 5 mm in diameter, If it were located outside the critical area of vision; 2mm, if it is totally or partially within the critical area of vision.
- The repaired area should be free of air bubbles.
- The repair should not change color over time.
- Repair should restore the structural strength of the glass.