How and from what glass and glass products are made. What is glass made of

The components that make up glass can be divided into the following types:

The foundation
Mandatory Alkali Metal Oxides
Components that give special properties
Excipients

Also in some cases, cullet is added.

The basis of any glass is quartz sand or silicon dioxide. Moreover, only selected sand, purified from iron impurities and from the slightest contaminants, gets into the mixture for future glass, about 2% of impurities are allowed. The transparency of the glass itself depends on this.

The required alkali metal oxides are different depending on the type of glass. For example:

for window glass, oxides of sodium, calcium or aluminum are used
for crystal - oxides of potassium and lead
for laboratory - oxides of sodium, potassium, boron
for optical - oxides of barium, aluminum, boron

Components to impart special properties are selected based on the desired effect, for example, titanium or barium oxides are added to impart heat resistance, and so on.

Auxiliary substances are mostly illuminators, bleaches and dyes.

Industrial glass production

It all starts with the fact that all the necessary substances are brought to the production plant. The main components of what glass is made of are quartz sand, dolomite, soda, lime. All substances undergo preparatory processing. Sand is cleaned of iron impurities, dolomite and lime are crushed in a crusher. After that, all substances are mixed and at this stage the components necessary to impart certain properties are also mixed in. This whole mixture is called a mixture. A mixture is a mixture that is already completely ready for further processing, that is, it is already exactly what glass is made of.

The technological process for the manufacture of glass begins. The finished charge goes through the conveyor into the bunkers, from which it is poured into the loader, and the loader already pushes it into the furnace. Since the temperature here ranges from 1200 to 1600 degrees, depending on the type of future glass, such a furnace operates continuously for several years. Because you can’t just take and turn off such a furnace, otherwise it will simply collapse. In order to turn off such an oven, it will take about a week of uniform cooling. At this temperature, the charge turns into glass mass.

From the furnace, this glass mass first enters a tank with a stirrer, and after it is well mixed, it flows into the stubbing chamber. Here it cools down to about 1000 degrees. From the student part, the glass melt enters the fleet bath. At this stage, an interesting process occurs. A navy bath is a bath of molten tin, the temperature of which is about 600-700 degrees Celsius. On this tin, the glass melt literally floats and cools down a little, it is thanks to this technology that it acquires an almost perfect plane.

After a bath with tin, the glass ribbon enters the firing lehr, which is more than 100 meters long, rolling over which it gradually cools.

The next step is cutting the tape into sheets of glass. This is where some very clever technology comes into play. Cutting takes place directly in the direction of the tape, which significantly speeds up the entire process of glass production. How can you cut the tape on the go, you ask. The fact is that the cutter moves at exactly the same speed as the tape and at this time cuts it across, after which it returns to its original position. So we get finished sheets of glass.

Now, such equipment as a stacker machine comes into operation. As the name suggests, she makes stacks of glass. The movement of glass sheets occurs with the help of suction cups, since the glass is very fragile, but it weighs quite a lot, it cannot be moved in any other way. After the stacks are formed, they are transported by a special loader, and then the glass is distributed to warehouses, shops, to places where double-glazed windows are made from them, and so on.

By the way, why is glass transparent? The fact is that quartz sand is completely transparent. But we cannot see anything through the grains of sand due to the multiple refraction of light. For example, if you break the glass into many pieces, then you will not see anything through them either. And when the sand turns into a smooth mass, then here we already see a transparent sheet of glass.

Manufacturing of glass products

Glass products can be divided into two large types. The first are those products that are produced on an industrial scale, the so-called glass containers, such as glass bottles, jars. The second big type is art products. This is the name of all products that are made by hand by glassblowers, such as vases, glass figurines, figurines and the like. In the manufacture of glass products, industrial glass and in general any glass, the initial stage of production is always absolutely similar, until the glass mass is obtained. Only the components that make up the charge, the melting temperature and the subsequent processing of the resulting glass mass are different.

Manufacture of industrial glass products

The finished glass mass from the furnace falls into a line of glass, from which it flows out in the form of a sausage and is cut into cylindrical drops by a cutter, one such drop is a future bottle or jar. The drop is sent to a so-called scoop, which directs them to the molding machine. It works by the following method: the holders take the drop by the edge and hold it in a hanging position, the entire lower part of the drop is closed on both sides with the desired shape, whether it be a jar or a bottle, certain patterns can also be on the shape. After the mold is closed, the holder is removed and a blowing device is inserted into the drop. It, like a balloon, inflates the drop from the inside with compressed air and the mass acquires the desired shape. Excess molten glass goes back to its original shape.

By the way, to give the glass some color or shade, certain substances are added to the mixture, for example, iron or chromium oxide is added to give green color, copper oxide for blue, and so on.

Now almost finished products move along a heated conveyor so that there is no sharp temperature drop and the product does not crack. From this conveyor, the loading machine moves the products into a lehr, along which they move slowly and gradually cool down. Here they are treated with a special solution that allows them to glide and move smoothly. And they move on to the testing and packaging line. After going through all the stages, we get the finished product.

How art glass products are made

Artistic glass products are all made from the same glass mass. In the production of such products, the same furnace is still used, but only the temperature for manufacturing is slightly lower than industrial, about 1200 degrees. The product itself is made by glassblowers. Glassblowers are like jewelers for glass, they can work alone or in pairs or even more.

With the help of a long tube, glassmakers take the required amount of hot glass directly from the furnace and immediately begin to shape it using various methods, while periodically blowing it through the tube. In the process, it will be possible to add more material, for example, for any additional details. Very small details are made separately, also by different methods.

After forming the details and the general shape of the product, it is placed in another kiln for a day. As a rule, the temperature in the heated state is about 400 degrees, at night such a furnace is turned off and the products in it gradually cool down to 70 degrees, where they harden and harden.

Faced with glass products every day, few of us think - what is glass made of? How is the production process going? Appearing in ancient Egypt 5 thousand years ago, the glass was very cloudy, and had an unattractive appearance. The material we are dealing with now was obtained much later.

glass composition.

Pure glass is used for glass quartz sand(about 75%), lime and soda. To obtain a product with specific properties, oxides and metals can be included in the composition.

Boric acid oxide. Reduces the coefficient of thermal expansion of the resulting products, and increases the gloss and transparency of the finished products.
Lead. This component is added during the production of crystal. Crystal products are colder to the touch and have a characteristic luster and ringing for this material.
Manganese. The addition of this heavy metal contributes to the production of products with a green tint. In addition to manganese, with the help of nickel, chromium or colt, you can get products of other colors.

physical properties.

The most important characteristics of glass:

Density. This characteristic depends on the chemical composition and ranges from 2200 to 6500 kg/m³. As the temperature rises, the density of the glass decreases and it becomes particularly brittle.
Strength. Depending on the type of glass, its strength varies from 50 to 210 kgf/mm². A slight damage to the surface of the material reduces this figure by 3-4 times.
fragility b. The fragility of glass and its inability to withstand impact limits its use in some areas of life. When certain chemical elements are added to the composition of the material, this characteristic increases.
Heat resistance. Heat resistance - the ability of a material to withstand huge temperature changes. Ordinary window glass can withstand temperatures up to 90°C. In industry, these figures are increasing at times.

Types of glass.

Many products made of glass we see on the street and use in everyday life. These are glassware, light bulbs, glasses, windows. Depending on the physical and chemical properties, glass is also used in the production of shop windows, mirrors, lamps. What types of this homogeneous amorphous body exist and what is made of it?

Crystal glass. Contains lead oxide. High transparency and gloss give this glass an attractive and aesthetic appearance. They are mainly used for the manufacture of dishes and souvenirs.
quartz glass. The composition contains the purest quartz sand. Due to the fact that quartz glass products can withstand large temperature fluctuations, laboratory glassware, insulators, optical instruments, and windows are made from it.
foam glass. It is a glass mass, which has numerous voids in its composition. Excellent thermal and sound insulation properties have led to its widespread use in construction.
glass wool. It has the appearance of thin glass threads with high tear resistance. They are used both in construction and in the chemical industry. Glass wool is fire resistant. Therefore, it is used as part of the material for sewing clothes for welders and firefighters.

To this list, you can add glasses that have specific properties :

Fire resistant. Resists open flame and withstands high temperatures.
Heat resistant. Has a low coefficient of thermal expansion and withstands sudden temperature changes
bulletproof. Impact-resistant glass that can withstand powerful impacts.

How is glass made?

Glass production includes the following steps in its process:

Preparation of the necessary materials. The prepared raw material needs special processing. Quartz sand is enriched, and iron impurities are removed from its composition. Limestone and dolomite are carefully crushed.
Mixing material in certain ratios. The amount of this or that material and its percentage in the prepared admixture depends on the required physical and chemical properties of the glass products.
Cooking in glass furnaces. The cooking step takes place at a high temperature, the range of which ranges from 800°C to 1400°C. There is an active process of melting quartz sand, and the glass becomes viscous and transparent.

After obtaining a homogeneous glass mixture, the future products are formed, the product is abruptly cooled, followed by thermal and physical processing.

Application in industry

The use of a transparent, wear-resistant and durable material with a smooth surface is amazing. Despite the fact that glass is a very fragile material, it is widely used in various fields of industry and everyday life.

mechanical engineering- is part of the non-stick paints that are used to process vehicles.
paper industry- impregnation of the finished paper pulp.
Construction- added to acid-resistant materials and refractory concrete structures.
Chemical industry- production of detergents.

This functional material can be bent, cut, melted and unique and beautiful products can be obtained from it. That is why colored glass is actively used for decorative work in the construction of public buildings and all kinds of souvenirs are made.

Glass categories

According to its purpose, glass is divided into the following categories:

Household glass. This group consists of five sub-groups - kitchen utensils, household utensils, lamp products, art products and household utensils.
building glass- sheet glass, shop windows, double-glazed windows, heat-insulating double-glazed windows, reinforced glass.
Industrial glass- laboratory instruments, protective products for industry, glass wool, optics.

In addition to protecting our homes from wind, rain and cold, glass gives a person a vast area for creativity. The process of creating it is as beautiful and mysterious as the material itself. Transparent, hard, acid-resistant glass has become an indispensable material in architecture and everyday life.

In this article, we examined in detail what glass is made of. This material has taken a special, important place in a person's life; without it, many household items would have been much more difficult.

Video: the process of making a substance

31.10.2017 19:01 1279

Glass is an indispensable item in our lives. It is found everywhere: in residential buildings, shop windows and in all modes of transport.

Have you ever wondered what glass is made of?

People learned how to make glass in ancient Egypt about 5 thousand years ago, but unlike modern glass, it was not as transparent as it is now.

The main material for making glass is quartz sand. Lime and soda are added to it and heated in a special oven. Due to the interaction with soda, sand melts better. Lime also serves to strengthen the resulting material, and it does not collapse when interacting with water. If lime were not added, then the glass could simply dissolve on contact with water. When the temperature reaches 1700 degrees, all three materials mix and become one substance, which is lowered into molten tin at a temperature of more than 1000 degrees. Next, the resulting material is placed on a conveyor, where it is cooled to 250 degrees. In the same place, the glass is cut into standard parts and adjustable in thickness.

To obtain colored glass, in addition to soda and lime, compounds of chemical elements are added to sand. For example, green glass can be obtained by adding chromium, yellow by adding uranium oxide, and red by iron oxide. An oxide is a compound of a chemical element (for example, a metal) with oxygen.

Various forms of glass are obtained by blowing its red-hot mass. There is such a profession - a glass blower. This is a craftsman who makes glass of various shapes. The glassblower uses a special long tube in his work.

On its tip, he catches molten glass and blows out the resulting bubble. In this case, the glassblower rotates the tube, and the bubble enters a special wooden or metal mold. Sometimes masters make their masterpieces without forms. They process the bubble blown out of the tube with the help of tools (forceps, scissors, trowels, etc.), giving it various shapes.

Glass is a material that has no analogues in some properties. Until now, natural ingredients are used for its production, the repeated processing of a damaged product can occur repeatedly without loss of quality and almost without waste.

Definition

Glass can be in several states of aggregation at different stages of production. And yet, glass - what is it and what is it made of?

According to the scientific definition, glass is any amorphous body obtained by the melt method, which, with increasing viscosity, acquires the properties of a solid body. The process of transition from one state to another is reversible.

Material history

In everyday life, we use glass every day. What it is and what it is made of - these are rarely asked questions in modern times, the material is so familiar to us. Scientists believe that glass was first obtained by accident, it is impossible to trace the origin of technology. The first products date back to around 2540 BC. Three components were present in the ancient recipe - soda, sand and alumina. In the future, they learned how to improve the properties of the material by adding chalk, dolomite and other components to the main ingredients. The entire composition from which glass is brewed is called charge.

Colored glass began to be obtained using natural pigments - chromium oxide, nickel oxide, cobalt additives. The first molded product was obtained in the 1st century AD by Roman craftsmen. They also invented sheet glass. The technology for the production of glass in sheets consisted in blowing a huge, human-sized cylindrical bubble from a hot mass. Until it cooled, it was cut along the long part and laid out on pallets for alignment. This technique was widespread until the beginning of the 20th century. In Russia, glass production was opened in the 17th century and was located in the village of Dukhanino, at that time only foreigners were masters.

Compound

Glass is used for many purposes. What is glass, we figured out, and what are its main ingredients? The composition of the initial ingredients for the entire period of the practice of manufacturing the material has not changed. Three main components make up the base (charge) - silica or quartz sand, soda (sodium oxide) and calcium oxide, known as lime. The components are combined in certain proportions and melted in a furnace at a temperature of 300 to 2500 ° C. Depending on the desired properties, potash, boric anhydride, broken glass from previous melts or recycled raw materials are added to the composition of the charge, depending on the desired properties.

Technology

To enhance or weaken the properties of the compounds, enhancers, opacifiers, dyes, decolorizers, etc. are added to the melting process. After cooking, the mass is quickly cooled, which makes it possible to avoid the formation of crystals. Of all the components, the largest percentage in the recipe is sand - from 60 to 80%. The sand acts as a core around which the vitreous material is formed. Glass production technology has remained unchanged for centuries.

Lime is another component without which glass cannot be produced. What is calcium oxide in the ingredients? This component gives the material chemical resistance and enhances gloss. Glass can only be smelted from sand and soda, but without lime it will dissolve in water. The third player in the mixture is metal oxide - sodium or potassium (up to 17%). It is introduced into the mixture in the form of soda ash or potash. These components reduce the melting point, allowing individual grains of sand to completely melt and combine into a monolith.

Kinds

Depending on the components used in the mixture, the types of glass are divided:

Quartz. It is made from one component - silica. It has high qualities: resistant to high temperature (up to 1000 °C) and thermal shock, transmits the visible and ultraviolet radiation spectrum. Production is associated with high energy costs, since silica (silicate glass) is a refractory raw material and is difficult to mold. The main areas of application are chemical and laboratory glassware, parts of optical systems, mercury lamps, etc.
Sodium silicate. It is made of two components, glass composition - silicate sand and soda (1:3). Due to its properties, it is widely used in industry as a component of any process, but is not used in other areas, products are not made from it. The main disadvantage is that it dissolves in water.
Lime. The most common type of material from which most products are made is sheet glass, glass containers, mirror sheets, dishes and much more.
Lead. Lead oxide is proportionally added to the classical composition of glass (charge). Lead glass is characterized by increased dielectric properties, which allows it to be used as the best insulating composition in television tubes, oscilloscopes, capacitors, etc. The presence of lead in the glass mass gives the material additional shine, sparkle, which is often used in the manufacture of art products, dishes, etc. e. Crystal - one of the types of lead glass.
Borosilicate. The addition of boron oxide to the composition of the material increases its resistance to thermal shock up to 5 times, and the chemical properties are significantly improved. Borosilicate glass is used for the manufacture of pipes and laboratory-chemical glassware, household products. A large-scale use case is a borosilicate glass mirror for the world's largest telescope.
Other types of glass - aluminosilicate, borate, colored, etc.

Types of window glass

Window glass is the most demanded type of material. It transmits sunlight, provides thermal insulation in winter and summer, prevents the penetration of noise, aesthetically decorates the window opening and performs many other functions. Today there is a wide choice of types of glass, each of which meets certain requirements:

Energy saving. A type of glass tinted in bulk or covered with a special film, which ensures the penetration of short-wave solar radiation into the room, and the long-wave radiation of heating devices is not released from the room. The second name is selective glass. To date, several types of coatings have been developed. The most promising are - K-glass (deposition of metal oxides on the surface) and i-glass (vacuum multilayer deposition of silver - dielectric).
Sunscreen. Reduces the transmission of sunlight into the room. They are divided into two types - reflective and absorbing. The effect is achieved either by tinting glass in bulk during cooking, or by applying a special film to the surface.
Decorative. Window glass with additional aesthetic characteristics - patterned, colored, etc.

Safety glasses

One of the negative qualities of glass is its fragility, there are technologies for strengthening the material. The most common types:

Reinforced. Sheet glass, during the formation of which a metal mesh is introduced into the mass. Scope of application - industrial premises, street lighting, lining of elevator shafts, etc.
Laminated or triplex. Two or more glasses are held together with a special film or liquid. This type of material significantly reduces the noise level in the premises. Also, when using additional color filters during lamination, it can perform sun protection functions. Triplex has increased mechanical stability, when the sheet is broken, the fragments remain attached to the film, which makes it as safe as possible for use in facade, balcony, window, and door glazing.
fire resistant. Most often, it is produced using the lamination technology with special films, which at temperatures above 120 ° C change their physical properties and, expanding, become dull, giving the glass rigidity.
Protective. It is a multilayer material consisting of several types of glass bonded with a polymer film. For example, silicate glass is bonded to polycarbonate and organic glass. Such a translucent block is resistant to mechanical, chemical, shock damage. Security glass types include bulletproof, impact-resistant, puncture-resistant and other types. Technical requirements for the material and classification of protective glasses are regulated by GOST R 51136.
Tempered. Possesses high strength characteristics. The effect is ensured by the technology of glass production - in a special tunnel furnace, the sheets are exposed to high temperatures for a short time and are quickly cooled. When broken, tempered glass shatters into small pieces that do not pose a threat to life and health. The disadvantage is the impossibility of mechanical processing of the hardened web; at the slightest impact, it collapses. Most tempered glass products are first shaped, cut, or otherwise processed before being tempered.

Auto Glass

Glasses for cars have increased strength characteristics that meet safety requirements. To date, two technologies are used in production - lamination (triplex) and hardening (stalinite):

Tempered is obtained by heat treatment of ordinary silicate glass, heating it in a furnace to a temperature of +600 ° C, followed by rapid cooling. It acquires mechanical and thermal strength, but with strong impacts it collapses, disintegrating into small safe fragments that lack cutting and piercing edges. Russian marking - the letter "Z", European - "T" or Tempered.
Laminated - these are two thin sheet glasses bonded with a polymer film under the influence of temperature and vacuum. The properties of glass are such that it remains intact under strong impacts, does not break into fragments if it bursts. Parts remain bonded with film. The triplex has additional features - tinting with color filters during lamination, additional interior noise insulation, low thermal conductivity, etc.

Modern developments

The twentieth century can be called a time of widespread use of glass. After the development of the technology of mechanical methods for obtaining the material, it began to be used in various fields - as the thinnest fiber in the fields of telecommunications, with no less success it is used in large multi-ton blocks in building technologies.

The properties of glass are diverse, they are still being studied in scientific institutions, and craftsmen find new ways to use and invent new types. In 1940, glassmakers introduced foam glass to the world. Its qualities are:

Lightness - does not sink in water, has a cellular structure, the specific gravity slightly exceeds the weight of the cork.
Moisture resistance, durability.
Environmental friendliness (coke is added to the classic batch recipe).
Fireproof (does not burn) and dampens fire.
The material can be sawn into pieces without compromising quality.

The scope of application was insulating materials for hazardous industries, cold stores, etc.

For solar cells, glass is used with a conductive coating of a thin layer of metal oxide. Coated panels operate at temperatures around 350°C. In addition, such glass is mounted in aircraft cabins to avoid ice and keep heat inside the cabin.

An important achievement of modern times was the possibility of producing glass ceramics. The material is made using the technology of ordinary glass, but at the last stage of cooling, the process slows down, and crystallization occurs in the mass of the material. Catalysts are special additives that do not affect the external state of the glass, but form small crystals. The material withstands high temperatures without deformation and is more resistant to all kinds of damage. Used in rocket science, household appliances, laboratories, engine parts and many other fields.

Glass is the most ancient object that has been found by man and is still used today. Found because a person did not invent it himself and made it for the first time. Most likely, the first glass appeared many thousands of years ago from volcanic lava. Now this substance is commonly called obsidian. How is glass made? Let's go back to the days when it didn't exist. Gradually, people got to know the surrounding nature and noticed that when natural soda is mixed with sand and then heated, a transparent substance appears. That is how they became aware of this new type of material. This process was described by Pliny, the ancient Greek encyclopedist. It was from that moment that the history of the use of glass began, which has become absolutely indispensable in our life today. After all, now it is used everywhere.

However, there is another theory about how glass is made, more precisely, how it was produced before. Some scientists have decided that the vitreous material was identified as a by-product of copper smelting or roasting. In human life, this product has played a truly outstanding role. It is difficult to overestimate its importance. The production of sheet glass is comparable to such discoveries as the extraction of fire and the invention of the wheel. In the days of Ancient Egypt, it was customary to make all kinds of jewelry from it. Later, they learned to produce containers for liquids from it. From the thirteenth century there was a dramatic increase in the amount of glass produced. Venice became the center of its production. The craftsmen became aware of the technology for creating oriental glass, after which they began to develop and improve it. The transparency of glass was made possible by the addition of various impurities to it. Masters began to make various dishes from it, which were very thin and elegant. In those days, glass products served more as luxury items and decorations.

If the question of how glass is made is still interesting to you, then you can talk about how it found more and more new areas of application. The technology of its production has been improved. A mirror was invented, this was done by applying an amalgam to one side. Glass was also used in construction. Usually it was used in the construction of palaces and temples. And after the craftsmen learned how to make it colored, they began to decorate windows with it, making beautiful stained-glass windows. And now glass is widely used for fusing. And in science, over time, they began to use glass. Thanks to the discovery of its ability to concentrate and scatter light, a variety of lenses were created, telescopes and microscopes were made. These discoveries have become a giant step in the development of the natural sciences - medicine, biology, astronomy, physics and others. No activity is possible in any scientific direction without glasses.

How is glass made? Like once before, from the sand. At its core, sand contains quartz crystals presented here. When heated, it melts. If you cool it quickly, then the minerals will not have time to crystallize, becoming transparent. To give the product any color, oxides of various metals are added to it. To give the glass maximum transparency, the sand is cleaned so that it contains almost one quartz.

At the moment, there are many ways to obtain a product with different properties: reinforced, hardened, mirrored, armored. Even now, simple sand, which is being processed, serves as the basis. It is important to say that there is still enough sand on the planet, so glass will not soon go out of our everyday life.