Glass Glass is... Glass is one of the most ancient and, due to the diversity of its properties, a universal material in human practice. Physicochemically inorganic. Presentation on the topic “Glass

The substance and material is one of the most ancient and, due to the diversity of its properties, universal in human practice. The glass melting temperature, from 300 to 2500 °C, is determined by the components of these glass-forming melts. Transparency is not a common property for all types of glass existing both in nature and in practice. Glass

Glass production is based on the float process: molten glass melt is continuously fed from a bath furnace to the molten tin. While on it, the glass is shaped in thickness and width. The glass then enters the annealing furnace where it undergoes a cooling process. After annealing, the glass strip is cut to size for further shipment. The glass manufacturing process itself is continuous. Thanks to the use of various chemical compounds in their compositions, glasses have different properties, which makes it possible to create optical effects (the play of light in barely noticeable edges, creating the effect of glass that has melted over time). Glass can be either clear or colored, as well as frosted. The thickness of the glass is usually in the range from 4 to 6 mm. Manufacturing

The raw materials for production are pure quartz sand, soda and limestone. These substances are thoroughly mixed and subjected to strong heating (1500 C) Raw materials

There are five functions of glass, according to which types of glass are classified. These are: thermal insulation in winter, protection of the room from overheating in summer, sound insulation, safety, aesthetic function, functions of glass.

Quartz glass is produced by melting high-purity silica raw materials (usually quartzite, rock crystal), its chemical formula is Si. O 2. Quartz glass can also be of natural origin, formed when lightning strikes deposits of quartz sand. Optical glass - used for the manufacture of lenses, prisms, cuvettes, etc. Quartz glass

Glassy boric anhydrite is easily obtained by simply melting boric acid at 1200 -1300 o. C. Due to their excellent electrical insulating properties and comparative fusibility, borate glasses are widely used in electrical engineering. Some borate glasses are of interest for optics. Borate glass

The most important in practice belongs to the class of silicate glasses. No other classes of glass can compare with them in terms of their prevalence in everyday life and in technology. The decisive advantages of silicate glasses are due to their low cost, economic availability, high chemical stability in the most common chemical reagents and gaseous media, high hardness, and comparative simplicity of industrial production. Silicate glass

It is used as sheet glass in aircraft and mechanical engineering, for the manufacture of household products, protective equipment in laboratories, construction and architecture, instrument making, glazing of greenhouses, domes, windows, in medicine - prostheses, lenses in optics, pipes in the food industry, etc. Organic glass

Glasses consisting of atoms of one element are called elemental. Sulfur, selenium, arsenic, and phosphorus can be obtained in a glass-like state. There is information about the possibility of vitrification of tellurium and oxygen. When cooling 11 o. C gives a rubbery, transparent product, insoluble in carbon disulfide. Elementary stele

When determining the class, the nature of the glass-forming oxide included in the glass is boron oxide, silicon oxide, and phosphorus oxide. Many oxides transform into the glass state only under conditions of rapid cooling: arsenic oxide, antimony oxide, vanadium oxide, or aluminum oxide, tungsten oxide do not vitrify on their own, but in combinations the glass-forming properties are sharply enhanced. Oxide glass

They are used for the production of acid-resistant cements and concretes, for impregnating fabrics, for the production of fire-retardant paints, silica gel, for strengthening weak soils, etc. Fiberglass - artificial fiber is widely used in the chemical industry for filtering hot acidic and alkaline solutions, purifying hot air and gases; Fiberglass materials are used in construction and for corrosion-resistant pipelines, in the manufacture of electrical insulation, etc. Soluble glass

a promising building material for the new, 21st century. Reserves of quartz sand, from which glass is made, will almost never run out! And there are a lot of possibilities. Now glass nails have been invented.

Durable, do not rust or

Glass Definition:

This is the state of an amorphous substance that is obtained when a supercooled liquid solidifies.

1. History and relevance of the topic.

2. Obtaining glass melt

3. Glass products

4. Applications and types of glass:

Energy-saving (heat-protective)

Tinted, Colored and Mirrored

glassPatterned glass

Safe and durable glassSafety glass

1. History

A hundred and fifty years ago, glass was boiled only in fireproof vessels. They were manually filled with a mixture consisting of quartz sand, soda, chalk, dolomite and other materials. The mixture at high temperature turned into a transparent mass. From liquid glass melt, glassblowers blew various vessels, bottles, dishes or cylinders, from which they then produced sheets of glass. It was hard work. In the 30s. In the last century, the first bath furnaces for industrial glass production appeared in Russia. The need for it grew very quickly. Factories began to make glass. And each had one or more bath furnaces that produced tons of glass per day.

Modern bathroom stoves are large structures. The length of the furnace for the production of window glass is several tens of meters. The charge is continuously loaded into the furnace at a rate of 10-15 tons per hour using mechanical devices. The furnace holds more than 2500 tons of glass melt and produces 350 tons of glass or more per day.

Even at high temperatures, glass melt has a high viscosity, tens of thousands of times greater than water.

Therefore, gas bubbles linger in it for a long time,

secreted by soda, chalk and other components of the charge.

The larger the furnace and the higher the glass melting temperature, the more productive the furnace is. You can increase the glass melting temperature if you not only heat the furnace with gas or liquid fuel, but also use the electrothermal effect in the glass melt itself. After all, glass melts at high temperatures

conducts electric current. Now the temperature of bathtub stoves is increased to 16000C and electric heating is widely used.

Every year we produce hundreds of millions of square meters of window glass. Moreover, they have learned to make strong pipes, fiberglass, fiberglass, armored glass, hollow building blocks, and complex, heat-resistant laboratory glassware from glass. Glass successfully competes with metal. This is a very promising material in a wide variety of sectors of the national economy.

Glass is also of great importance in our everyday life - it is various dishes, vases, mirrors...

The larger the furnace and the higher the glass melting temperature, the more productive the furnace is. It is possible to increase the glass melting temperature, if not only

heat the stove with gas or liquid fuel, but also

Technologist

Receiving glass:

Receipt

glass melt

Receive

glass

Preparation

materials

Mixing them in certain proportions, in accordance with the given chemical composition of the glass, into a homogeneous

Cooking the charge in

glass melting furnaces to obtain a homogeneous liquid

glass melts.

Bringing to temperature and

viscosity

Product molding

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Glass is... Glass is one of the most ancient and, due to the diversity of its properties, a universal material in human practice. Physico-chemical inorganic substance, solid; structurally amorphous, isotropic; Collectively, all types of glass are extremely viscous supercooled liquids that reach a glassy state during cooling at a rate sufficient to prevent crystallization of melts obtained within specified temperature limits (from 300 to 2500 ºC), which are determined by the oxide, fluoride or phosphate origin of their compositions. Glass is one of the most ancient and, due to the diversity of its properties, a universal material in human practice. Physico-chemical inorganic substance, solid; structurally amorphous, isotropic; Collectively, all types of glass are extremely viscous supercooled liquids that reach a glassy state during cooling at a rate sufficient to prevent crystallization of melts obtained within specified temperature limits (from 300 to 2500 ºC), which are determined by the oxide, fluoride or phosphate origin of their compositions.

History of glass It has not yet been established reliably how and where glass was first obtained. For a long time, the primacy in the discovery of glassmaking was recognized in Egypt, which was undoubtedly evidenced by the glass-glazed faience tiles of the internal cladding of the Jesser pyramid (mid-3rd millennium BC); Finds of faience jewelry (see above) date back to an even earlier period (the first dynasty of the pharaohs), that is, glass existed in Egypt already 5 thousand years ago. It has not yet been established reliably how and where glass was first obtained. For a long time, the primacy in the discovery of glassmaking was recognized in Egypt, which was undoubtedly evidenced by the glass-glazed faience tiles of the internal cladding of the Jesser pyramid (mid-3rd millennium BC); Finds of faience jewelry (see above) date back to an even earlier period (the first dynasty of the pharaohs), that is, glass existed in Egypt already 5 thousand years ago. Egyptian glassmakers melted glass on open fires in clay bowls. The sintered pieces were thrown hot into the water, where they cracked, and these fragments, the so-called frits, were ground into dust by millstones and melted again. Egyptian glassmakers melted glass on open fires in clay bowls. The sintered pieces were thrown hot into the water, where they cracked, and these fragments, the so-called frits, were ground into dust by millstones and melted again. Ancient vase

Art glass Art glass is a very old craft. Not only dishes, window glass, lenses and other utilitarian objects were made from glass, but also a variety of artistic products. Art glass is a very old craft. Not only dishes, window glass, lenses and other utilitarian objects were made from glass, but also a variety of artistic products. Glass blowing is an operation that makes it possible to obtain various shapes of balls, vases, and glasses from a viscous melt. Glass blowing is an operation that makes it possible to obtain various shapes of balls, vases, and glasses from a viscous melt. The most important working tool of a glassblower, his blowing tube, is a hollow metal tube 1-1.5 m long, one-third lined with wood and equipped at the end with a brass mouthpiece. Using a pipe, a glass blower takes molten glass from a furnace, blows it into a ball shape and shapes it. The finished product is kicked off the tube onto a fork and carried into the annealing furnace. The mark left from knocking off (nozzles, caps) must be removed by grinding. The most important working tool of a glassblower, his blowing tube, is a hollow metal tube 1-1.5 m long, one-third covered with wood and equipped at the end with a brass mouthpiece. Using a pipe, a glass blower takes molten glass from a furnace, blows it into a ball shape and shapes it. The finished product is kicked off the tube onto a fork and carried into the annealing furnace. The mark left from breaking off (nozzles, cap) must be removed by grinding

History of the modern bottle The very first bottles in the modern sense were ugly - thick-walled, lopsided, made of cloudy, dirty glass with bubbles. However, they could already boast of their small size and certain convenience, and therefore quickly gained popularity. But still, a lot of time passed before the bottles acquired their modern slenderness and noble bearing. Of the first glass bottles, the most highly valued and most expensive were the products of Venetian craftsmen - intricately shaped, with rich gilding and applied details, also made of glass mass. The very first bottles in the modern sense were ugly - thick-walled, lopsided, made of cloudy, dirty glass with bubbles. However, they could already boast of their small size and certain convenience, and therefore quickly gained popularity. But still, a lot of time passed before the bottles acquired their modern slenderness and noble bearing. Of the first glass bottles, the most highly valued and most expensive were the products of Venetian craftsmen - intricately shaped, with rich gilding and applied details, also made of glass mass. The heart of this glass industry was the island of Murano - it was there that, due to the threat of fires, all glass production of the Venetian Republic was transferred in 1292. The craft reached its peak in the 15th century and was caused by the advent of new glassblowing technology and new methods of glass processing. At the same time, the craftsmen of the island of Murano learned to make not only colored, but also white (aka “milk”) glass, which immediately became fashionable in Europe... The heart of this glass industry was the island of Murano - it was there because of the threat of fires in 1292 The entire glass production of the Venetian Republic was transferred. The craft reached its peak in the 15th century and was caused by the advent of new glassblowing technology and new methods of glass processing. At the same time, the craftsmen of the island of Murano learned to make not only colored, but also white (aka “milk”) glass, which immediately became fashionable in Europe... In those days, when glassmaking developed in Venice and Venetian products became known outside the Apennines peninsula, the local craftsmen, as well as the glassblowers of the cities of Faenza and Urbino, put a lot of effort and skill into the production of bottles. The bottles made by these masters (cast in special metal molds) became real works of art - bizarre in appearance, tall and graceful, flat or almost spherical. They were decorated with convex relief designs depicting flowers, fruits and even various scenes from mythology. At a time when glassmaking developed in Venice and Venetian products became known outside the Apennine Peninsula, the local craftsmen, as well as the glassblowers of the cities of Faenza and Urbino, put a lot of effort and skill into the production of bottles. The bottles made by these masters (cast in special metal molds) became real works of art - bizarre in appearance, tall and graceful, flat or almost spherical. They were decorated with convex relief designs depicting flowers, fruits and even various scenes from mythology. It was in such bottles that wines, other drinks and seasonings were served on the table in rich houses. Simpler bottles were used to store liquid products, but they were also considered quite expensive in those days. It was in such bottles that wines, other drinks and seasonings were served on the table in rich houses. Simpler bottles were used for storing liquid products, but they were also considered quite expensive in those days. Starting from the 17th-18th centuries, medicines and perfumes began to be stored in modern glass bottles. Exactly the same 18th century. was marked by an incredible rise in the wine trade, which, in particular, was famous for the Age of Enlightenment. Manufacturers were forced to solve the problem of exclusive designation of their product brands on bottles. The main problem was that the appearance of the products invariably had to attract the whimsical gaze of a fastidious buyer with its elegance. Starting from the 17th-18th centuries, modern glass bottles began to store medicines and perfumes. Exactly the same 18th century. was marked by an incredible rise in the wine trade, which, in particular, was famous for the Age of Enlightenment. Manufacturers were forced to solve the problem of exclusive designation of their product brands on bottles. The main problem was that the appearance of the products invariably had to attract the whimsical gaze of a fastidious buyer with its elegance. The sealing wax, which was used to cover the bottle cap until that time, is a short-lived material: seals were easy to forge. Around the end of the 18th century. The custom of marking the wine bottle itself with seals, not sealing wax, became fashionable immediately before putting it on sale. Plus, the quality of the product was additionally confirmed by excise lead stamps, with which customs officials supplied wine boxes sent on a long journey. The sealing wax, which was used to cover the bottle cap until that time, is a short-lived material: seals were easy to forge. Around the end of the 18th century. The custom of marking the wine bottle itself with seals, not sealing wax, became fashionable immediately before putting it on sale. Plus, the quality of the product was additionally confirmed by excise lead stamps, with which customs officials supplied wine boxes sent on a long journey. Somewhat later, after the Napoleonic wars, which almost undermined the export of Portuguese port wine to England, information about the contents began to be applied to the mold before casting the glass bottle. At the same time, chemists synthesized glue, with the help of which it became possible to attach a label to bottle glass. The further - the more: wine merchants invented the most incredible forms of bottles for bottling intoxicating drinks, and all these forms were patented. Somewhat later, after the Napoleonic wars, which almost undermined the export of Portuguese port wine to England, information about the contents began to be applied to the mold before casting the glass bottle. At the same time, chemists synthesized glue, with the help of which it became possible to attach a label to bottle glass. The further - the more: wine merchants invented the most incredible forms of bottles for bottling intoxicating drinks, and all these forms were patented. Today, bottles are one of the most popular types of glass products. They are very diverse in purpose, shape, color and capacity. Wine bottles differ quite greatly from each other: champagne, Bordeaux, Burgundy, Rhine, as well as those intended for strong and dessert wines and special wines such as Tokay, port, vermouth, Malaga and many others. etc. Today, bottles are one of the most popular types of glass products. They are very diverse in purpose, shape, color and capacity. Wine bottles differ quite greatly from each other: champagne, Bordeaux, Burgundy, Rhine, as well as those intended for strong and dessert wines and special wines such as Tokay, port, vermouth, Malaga and many others. etc.

Glass bottles Glass is a very ancient packaging material: glass vessels were used in Egypt and Syria as early as three thousand years BC. e. At the same time, glass production technology is very static. Previously, bottles were blown using a special glass-blowing tube made of metal (usually iron) and covered approximately one-third with wood. On one side of the tube there was a mouthpiece, on the other there was a special pear-shaped thickening for collecting glass. After the tube was heated up, it was lowered (thickening down) into the molten glass mass and turned so that the glass mass stuck to the “pear”. The glassblower quickly pulled out the tube and, turning it so that the molten glass was held, inserted it into a special hollow mold made of clay or metal and began to blow vigorously into the mouthpiece. The resulting glass bubble filled the inside of the mold, forming a hollow bottle. Glass is a very ancient packaging material: glass vessels were used in Egypt and Syria as early as three thousand years BC. e. At the same time, glass production technology is very static. Previously, bottles were blown using a special glass-blowing tube made of metal (usually iron) and covered approximately one-third with wood. On one side of the tube there was a mouthpiece, on the other there was a special pear-shaped thickening for collecting glass. After the tube was heated up, it was lowered (thickening down) into the molten glass mass and turned so that the glass mass stuck to the “pear”. The glassblower quickly pulled out the tube and, turning it so that the molten glass was held, inserted it into a special hollow mold made of clay or metal and began to blow vigorously into the mouthpiece. The resulting glass bubble filled the inside of the mold, forming a hollow bottle. By and large, the only serious innovation before the beginning of the twentieth century was the invention a hundred years BC. e. glass blowing tube. In addition, the master was not always able to maintain the beauty of the form. The lower part of the vessel, as a rule, turned out to be more massive than the upper, since the bottle was blown from a hot glass bubble, pulling it up to the neck. The final shape - damask, cone or round - was also given to the bottle by hand, “rolling” it on special figured surfaces made of bog oak. The bottles were heavy because the glass mass contained metal salts. By and large, the only serious innovation before the beginning of the twentieth century was the invention a hundred years BC. e. glass blowing tube. In addition, the master was not always able to maintain the beauty of the form. The lower part of the vessel, as a rule, turned out to be more massive than the upper, since the bottle was blown from a hot glass bubble, pulling it up to the neck. The final shape - damask, cone or round - was also given to the bottle by hand, “rolling” it on special figured surfaces made of bog oak. The bottles were heavy because the glass mass contained metal salts.

Only in 1901, when the first automatic bottle machine was patented, did the real development of the mass glass industry begin. Glass is a very characteristic material. The main specificity is that it must be processed in an extremely hot and semi-liquid state. The molding or blowing operation is very short-lived, it must be completed in just a few seconds (in some individual cases, in a few minutes). After this, the glass loses its plasticity. By and large, bottle blowing technology has undergone only minor changes since then. Another thing is that this process today is completely automated. The molten glass melt from the glass melting furnace flows into the feeder, from where it is squeezed out in a fixed portion through a special hole and cut off with mechanical scissors. The resulting drop of a certain weight falls into the rough form of a glass-forming machine, where the neck rim is formed and the body of the bottle is pre-inflated. Then the rough mold is opened and the resulting blank is moved to the finishing mold, where the final formation of the product occurs. Frozen bottles are subjected to annealing and slow cooling. The quality of annealing is determined by the term “the thermal history of the glass.” Good annealing allows you to get rid of internal stresses inside the glass, due to which the finished product can crumble into small pieces at the slightest impact, increase in pressure (pouring) or temperature (pasteurization). Only in 1901, when the first automatic bottle machine was patented, did the real development of the mass glass industry begin. Glass is a very characteristic material. The main specificity is that it must be processed in an extremely hot and semi-liquid state. The molding or blowing operation is very short-lived, it must be completed in just a few seconds (in some individual cases, in a few minutes). After this, the glass loses its plasticity. By and large, bottle blowing technology has undergone only minor changes since then. Another thing is that this process today is completely automated. The molten glass melt from the glass melting furnace flows into the feeder, from where it is squeezed out in a fixed portion through a special hole and cut off with mechanical scissors. The resulting drop of a certain weight falls into the rough form of a glass-forming machine, where the neck rim is formed and the body of the bottle is pre-inflated. Then the rough mold is opened and the resulting blank is moved to the finishing mold, where the final formation of the product occurs. Frozen bottles are subjected to annealing and slow cooling. The quality of annealing is determined by the term “the thermal history of the glass.” Good annealing allows you to get rid of internal stresses inside the glass, due to which the finished product can crumble into small pieces at the slightest impact, increase in pressure (pouring) or temperature (pasteurization).

Prepared by: biology teacher
and chemistry Korotaeva G.V.

History of glass (technology) For a long time, the primacy in the discovery of glassmaking was recognized in Egypt, which was undoubtedly evidenced by the glass-glazed faience tiles of the internal cladding of the Jesser pyramid (mid-3rd millennium BC); Finds of faience jewelry date back to an even earlier period (the first dynasty of the pharaohs), that is, glass existed in Egypt already 5 thousand years ago.

Development of the glassblowing industryFrom the beginning of the 13th century. The glassblowing industry in Venice developed extremely quickly. Traders brought samples of oriental glass from Constantinople, taking possession of the secrets of the craft, and soon the Venetian glassmakers had no rivals either in Italy itself or in Europe.
The city authorities carefully monitored that the secrets of craftsmanship did not penetrate the borders of Venice. Decrees were issued according to which the export of “raw” glassmaking materials (materials for preparing glass mass) from the country was prohibited.
The masters and their families were threatened with prison, and even death, for attempting to leave Venice. There was a carrot and stick policy towards glassmakers. They were generously given awards and assigned to the privileged strata of society. The master glassmaker had the right to marry his daughter to the richest and most noble Venetian nobleman, and such a marriage was considered equal. But such favors did not please everyone. The masters ran away and founded their own workshops...
Many glass workshops appeared in the cities of Northern Italy - Padua, Ferrara, Ravenna, then in Germany (Nuremberg, Kassel, Cologne), in France (Nevers). This forced the government of the Venetian Republic to further tighten its policy towards glassblowers. The persecution intensified after another technological discovery, providing Venetian glass with superiority over the products of competitors.

Glass production technology The most important working tool of a glass blower, its blowing tube is a hollow metal tube 1-1.5 m long, one-third covered with wood and equipped with a brass mouthpiece at the end. Using a pipe, a glass blower takes molten glass from a furnace, blows it into a ball shape and shapes it. To do this, he needs metal scissors for cutting the glass mass and attaching it to the tube, long tweezer-shaped metal pliers for pulling and shaping the glass mass, for forming embossed decorations, etc., a saw for cutting the entire product from the tube, and a wooden spoon (rolling pin). , dolok - in the shape of a bobbin) to level the collected glass melt. The glass blower puts the glass (“jar”), pre-formed using these tools, into a mold made of wood or iron. The mark left by knocking off (nozzles, cap) must be removed by grinding.
The finished product is kicked off the tube onto a fork and carried into the annealing furnace. The product is annealed for several hours at a temperature of about 500°C in order to relieve the stress that has arisen in it. Because of them, an unannealed product can crumble at the slightest touch, and sometimes even spontaneously. For demonstration purposes, this phenomenon has long been effectively shown in Nabatavian tears - frozen drops of glass.
Glass grinding and polishing
Glass cut
Metallization and glass painting

Glass-forming substances Glass-forming substances include:
Oxides:SiO2;B2O3;P2O5;TeO2;GeO2
Fluorides: AlF3, etc.

Types of glassQuartz glass is produced by melting high-purity silica raw materials (usually quartzite, rock crystal), its chemical formula is SiO2. Quartz glass can also be of natural origin (see above - clastofulgurites), formed when lightning strikes deposits of quartz sand (this fact underlies one of the historical versions of the origin of the technology).

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Main industrial types of glass There are three main types of glass:
Soda-lime glass (1Na2O: 1CaO: 6SiO2)
Potash-lime glass (1K2O: 1CaO: 6SiO2)
Potassium-lead glass (1K2O: 1PbO: 6SiO2)
Soda Lime Glass
“Soda glass” can be easily melted, it is soft and therefore easy to process, and in addition, it is clean and bright.
Potassium-lime glass
“Potash glass,” in contrast to potassium glass, is more refractory, harder and not as plastic and moldable, but has a strong shine. Because previously it was obtained directly from ash, which contains a lot of iron, the glass was greenish in color, and in the 16th century manganese peroxide began to be used to decolorize it. And since it was the forest that provided the raw materials for the production of this glass, it was also called forest glass. A kilogram of potash required a ton of wood.

Slide No. 11

Optical glass - used for the manufacture of lenses, prisms, cuvettes, etc.
Chemical laboratory glass - glass with high chemical and thermal resistance.

Slide No. 12

Lead glass Lead glass (or “crystal”) is obtained by replacing calcium oxide with lead oxide. It is quite soft and fusible, but very heavy, has a strong shine and a high refractive index, decomposing light rays into all the colors of the rainbow and causing a play of light.

Slide No. 13

Brosilicate glass The inclusion of boron oxide instead of the alkaline components of the charge gives this glass the properties of refractoriness, resistance to sudden temperature changes and aggressive environments. Changes in composition and a number of technological features, in turn, affect the cost - it is more expensive than conventional silicate.

Slide No. 14

Porous glassesProducing porous glasses of significant size and thickness is possible only from glass of certain specific compositions. Porous glasses with a volume corresponding to the original one are relatively small and are formed from alkali-borosilicate glasses included in glasses of a more complex composition, and from two-component borosilicate glasses containing 60% SiO2.