In this article:
- Advantages of Tempered Glass
- Application of Tempered Glass
- Glass Tempering Technology
- Equipment required for the production of tempered glass
The technology of strengthening the strength properties of glass by tempering was developed back in 1929. Tempered glass is widely used all over the world, but in our country the demand for them can only be said to be growing steadily over the last 10-12 years. If in Europe every third glass used for glazing facades is thermally strengthened, then in Russia there is only one tempered glass for every 50 ordinary ones.
Material characteristics
Tempering glass is a treatment of the material that makes it 5-7 times stronger; it can withstand temperature changes from 60°C to 300°C. After tempering, glass becomes a heterogeneous object that cannot be cut, drilled into, or even broken. It resembles a balloon inflated with air - no matter how you try to cut it into pieces, it will eventually simply burst. According to quality standards, tempered glass measuring 50x50 mm, when exposed to a sharp metal object weighing up to 75 g, should crumble into 40-50 fragments.
Advantages of tempered glass:
- The impact strength of tempered glass is 5-10 times higher than usual, and the bending strength is 2-3 times higher.
- Operation is allowed at temperatures from -150 to +300 °C.
- The most important advantage is safety. When broken, tempered glass forms many small rounded fragments that cannot be cut.
- Durable material that will serve you for many years without special destruction.
- It has a very beautiful design, thanks to which it is often used when decorating modern furniture, doors and partitions in the apartment.
- It is possible to produce both transparent and frosted glass of any color, with or without a pattern.
You can see what tempered glass looks like in the photo.
Types of windshield cracks and how to repair them
Depending on the nature and cause of formation, several types of damage are distinguished - local, branching, radial, round and others. Not all types of defects can be repaired with superglue.
Not a through chip or a small local crack
Such defects occur when a light mechanical shock is caused by a pebble, a thick branch, or a small object with a pointed edge. A non-through chip usually does not create problems for the driver. However, it must be repaired, since it will grow and develop a through crack.
Optimal repair options:
- Super glue. Using superglue, you need to fill the resulting cavity and wait until it dries completely. The optimal choice is Super Moment glue (200-300 rubles) or Done Deal DD 6608 glue (300-400 rubles).
- Epoxy resin. A more durable material that can also be used to seal a cavity. Epoxy is sold in larger containers and is more expensive. Good options are Artline Crystal Epoxy (900 rubles), ED-20 (1000 rubles).
Radial crack
Formed by a strong mechanical shock using a small blunt object. Ray defects can grow over time, so repairs need to be done as quickly as possible. The best option would be to apply the polymer using a fixing suction cup, drill and special tape.
The work is carried out as follows:
- Using a scraper and a dry cloth, remove dirt, debris and dust from the surface.
- Small holes are carefully drilled in the edges, and the syringe is filled with polymer.
- A suction cup is mounted on the edge of the drilled hole, and glue is gradually injected into it.
- Tape is applied to the surface, and the car is rolled out into the sun for 15-20 minutes .
Note! If the defect has spread to the edge of the “lobovukha”, then instead of repairing it is necessary to perform a complete replacement (the polymer will not be able to reliably glue the edges, and the damage will spread further).
Branching
It is a scattering of branching rays, and such a defect is formed due to a strong mechanical shock or due to a sharp temperature change. Repair in this case is only possible if the defect has not extended to the edge. Repairs are made using polymer according to the algorithm indicated above, but with minor changes. Holes should be drilled at the ends of all branches to prevent further cracking. Drying is carried out not in the light, but indoors using ultraviolet lamps for 20-30 minutes.
Round
Formed by a sharp blow with a large blunt object, it looks like multiple circles and ellipses. There is no point in repairing such a defect, since the polymer will not be able to provide high-quality fixation of the edges. Therefore, if there is a round defect, a complete replacement is recommended . Although, before visiting a repair shop, you can drill small holes at the ends of the defect to slow down the spread of damage.
Tempered glass production technology
Glass tempering technology involves rapidly cooling the material from a temperature that is higher than the melting point of glass. At the same time, a high voltage is created inside the material, which makes the glass resistant to all mechanical influences. For greater efficiency, it is recommended to use a quenching medium, which has a higher cooling capability plus a change in heat transfer characteristics. The most popular such medium is air blown from an air jet grille, which can change the type of cooling - from natural cooling to forced cooling and vice versa.
In addition to air, liquids that can accelerate heat transfer can be used as an effective quenching medium, which makes the thickness of the tempered glass small and the thermal expansion coefficient lower. The degree of hardening will be higher than 4 pores/cm.
It can be:
- mineral oils;
- organosilicon liquids;
- molten salts and metals.
The disadvantage of using mineral oils and organosilicon liquids may be a poorly controlled cooling process - when hot glass gets on them, it causes boiling, which leads to a sharp change in the thermal output of the material.
The production of tempered glass using metal alloys is characterized by the following indicators:
- higher thermal efficiency coefficient than in the case of using organic liquids, which is especially sensitive at very high temperatures (from 600 °C);
- tempering of glass with low TRL is allowed;
- hardening with a high glass transition temperature is possible;
- possibility of tempering frosted glass.
The disadvantages include the high density of the medium, which makes it difficult to immerse the glass in it.
Glass tempering equipment
Today, technology has advanced so far that it makes it possible to produce and temper glass of the most complex shapes and sizes. One such modern equipment is a horizontal glass tempering system. With its help you can obtain tempered glass, the dimensions of which will be a maximum of 2100x3000 mm and from 4 to 12 mm thick.
The advantages of such a system include:
- Closed-type elements are used, which are heated to a temperature not higher than 750-780°C. This makes it possible for the glass not to suffer thermal shock, improves its characteristics and quality, and the equipment itself increases its service life without overheating. With open type elements, it becomes necessary to heat up to 1000-1050°C, which is more dangerous.
- High reliability in such equipment is ensured by a drive that can withstand the destruction of glass during the tempering process.
- Repair of the system is allowed, since all the main elements of the furnace are within reach.
Is it possible to drive a windshield with a crack?
By law, a crack in the windshield is not considered an obstacle to driving a car. Therefore, you can drive with any damage - with a ray-shaped crack, round, branching, and so on. The inspector does not have the right to fine the driver for having such a defect. However, repair or replacement is still recommended, since this is fraught with the following consequences:
- In some cases, it is impossible to pass a technical inspection (we will discuss this issue in more detail below).
- Poor visibility when driving, which can cause an accident.
- Some insurance companies refuse to pay CASCO insurance if the driver drove with damage and had an accident.
Tempered glass manufacturing operations
Before tempering glass, it must be properly prepared. The entire process from glass preparation to shipment of tempered glass consists of the following operations:
- selection of high-quality glass for tempering and rejection of unsuitable glass;
- cutting glass according to pre-made drawings;
- polishing the edge of the glass;
- drilling holes for fittings and fasteners;
- washing and drying of workpieces;
- quality control of workpieces;
- marking;
- glass tempering process;
- quality control of the resulting hardened products;
- packaging, loading and sending finished products to the customer.
How it is made
In production, knee glass can be made in two main ways:
- Thermal hardening.
- Chemical hardening.
For a number of reasons, Eraglass prefers to use thermally tempered glass. However, if the customer prefers, he will be provided with tempered glass made by chemical means. In any case, it will receive unbreakable glass that can withstand high loads and temperature changes without harm to users.
Glass Tempering Process
The glass tempering process itself consists of three stages:
- Heating the glass. The surface of the glass is heated to a temperature close to the melting point of glass. The glass begins to deform, but does not soften completely.
- Fast cooling of glass. At this stage, the surface of the glass is already cooled, but the substance inside continues to be heated and slightly viscous.
- Complete glass cooling. Tempered glass continues to cool until it is completely cool at room temperature.
Tempered glass cannot be cut, since under such mechanical influence it will inevitably crumble.
Application of Tempered Glass
The scope of application of tempered glass is very wide:
- window and door double-glazed windows;
- partitions and showcases;
- flights of stairs and steps;
- railings and canopies;
- automobile production.
Glazing of shopping centers and residential premises
In most cases, it is customary to glass the facades of modern shopping centers and residential buildings. For this purpose, double-glazed windows in aluminum profiles are used. Such structures let in more sunlight, but prevent ultraviolet rays from penetrating into the room. In addition, they are able to retain heat. Also, most partitions and display cases are made of glass; this greatly expands the internal space. In this case, the glass can be not only transparent, but also matte, colored or with any decorative pattern.
Glass showcases
Glass showcases attract buyers more than ordinary walls, even with the most beautiful sign. For the manufacture of such display cases, solid tempered glass or several glass parts are used, it depends on the size of the display case itself.
Glass doors and partitions
Glass doors and partitions are a new style in modern design. It is not only beautiful and cozy, but also safe and reliable. From tempered glass you can create unusual designs - sliding and pendulum. Glass doors allow you to visually enlarge and expand the interior space. This is especially true in small apartments.
Tempered glass has also found its application in furniture production. It is used to make table surfaces, cabinet doors and other elements. Tempered glass is especially often used in the kitchen as an apron.
How much does it cost to repair chips and cracks in glass in 2022 - 2022
You can repair or replace glass at auto repair shops. The cost of work will depend on many parameters.
- Repair. Repair is carried out according to the model “drilling + injecting polymer with a syringe + drying using a UV lamp.” The work will cost the driver 2-5 thousand rubles, and the cost will depend on the nature of the defect, the size of the damage, and the quality of the polymer.
- Replacement. When replacing, the technician removes the old glass and puts a new one in its place. The cost of the service is 5-15 thousand rubles (price of glass + work). The price is influenced by the type of glass (triplex or duplex), the make of the car, and the prestige of the auto repair shop.
Note! If you have CASCO insurance, then read the policy carefully - some insurers include free glass replacement in the list of available services.
Damage to the windshield comes in different types - local, radial, round and others. Small defects can be repaired using glue or epoxy resin. Medium-sized ones are sealed using drilling and injection of polymer compounds. According to the traffic rules, the driver has the right not to replace the glass - this is not considered an offense. However, his visibility may be impaired, and in some cases he will not be able to pass inspection.
Is it possible to temper glass at home?
Many people often have a question: how to temper glass at home? Unfortunately, this is not possible due to the fact that the process requires high temperatures, which cannot be achieved at home. The only thing you can afford is to harden the glasses so that they don’t break so much. To do this, you need to immerse the glasses in a container of water and let it boil. Then reduce the heat and boil the glasses for 5-6 hours, then remove the container from the heat and wrap it with a thick cloth. After complete cooling, the glasses can be removed and used for their intended purpose. They will be more durable and will withstand any boiling water.
