Sand, the main component is quartz (SiO2 glass is a strange material, the main component is quartz sand, the manufacturing process is quartz sand and other chemical raw materials after cooling at high temperature (1300 ℃), hard quality, wear resistance, high transmittance and corrosion resistance, its extensive application has a long history. With the increasing use of glass technology, the use of watches, tableware, doors and windows, lighting and high technology such as electronic components and space technology are indispensable to glass. We are most in contact with the "flat glass", thick doors and windows, thin watches and medical laboratory use, the method is to melt in the glass paste with horizontal or traction (also known as float) and vertical traction method into slurry, after the system pull out the system at the same time as the cooling system, after cooling into "flat glass", the faster the thickness of the main board glass, traction The faster the speed, the faster the traction speed and the thinner the fabric thickness. Although the ordinary flat glass looks bright and transparent from the front, it is slightly blue from the side near the edge, because the color of the glass depends on the depth. In the manufacture of glass, the main raw materials- The purity of quartz sand is better than that of thin glass selected by watch industry, but its value is more expensive. The main difference is that quartz sand is better raw material, and low (usually less than three thousandth of a thousand) glass raw material is mainly natural ore, so when making glass, the ore is first crushed, processed into powder, and then according to the composition of the glass, it is made into components and melted into glass to form glass Glass solution. The qualified glass flows through the feed chute and flows out of the feed port to form a material layer. The temperature of the material is 1150-1170 ℃ for alkali glass and 1200-1220 ℃ for non alkali glass. Cut the material into bulbs 200 times per minute. The blank slides through the chute and is divided into two different funnels, and then falls into a ball groove formed by the same rollers in three directions of rotation. The bulb rotates on the roller and has its own surface tension, and gradually forms a smooth round glass ball. The diameter is determined by the thickness of the glass flow, the velocity of the flow and the speed of the scissors. Glass balls from the cylinder, the temperature is still very high. In order to prevent ball sticking, cold ball or serpentine runway is required for cooling. In order to reduce the internal and external temperature difference between the glass ball and the residual stress, it is necessary to slow down the annealing. It is then stored in the ball for quality inspection. We know that solid materials can be divided into two categories: organic materials and inorganic materials. Organic materials include wood, plastic, plexiglass, cotton, wool, nylon, etc.

Inorganic materials can be divided into single crystal, polycrystalline and glass according to their structures. Single crystal has regular shape and strict structure rules, for example, ruby is alumina single crystal, crystal is silica single crystal, diamond is carbon single crystal. Polycrystalline is a large number of small single crystal aggregates, all kinds of ceramics, metals are polycrystalline materials. Glass is an amorphous solid obtained by melting, cooling and curing. Its structure has a certain rule (short-range order) in the atomic and molecular range, but in the macro range, there is no rule (remote disorder). It can rely on molds of various shapes. The irregular structure of glass determines the following properties of glass: isotropy, the arrangement of glass particles is usually irregular, but it is uniform and statistical, so its physical and chemical properties are the same in any direction. The crystal is anisotropic. For example: resistivity, thermal conductivity, transmittance, refractive index, etc. 2. There is no fixed melting point, and the glass changes gradually from solid to liquid in a certain temperature range. Although the crystal has a definite melting point, for example, ice (crystal) melts at 0 ℃. This characteristic of glass enables it to be blown, drawn, pressed and other forming methods. 3. The composition and properties of the glass are adjustable, and the glass and its composition change continuously and gradually in a certain range. Although the crystal has a fixed composition and certain properties. In this way, we can adjust the composition of the glass to make its performance meet the requirements. How to produce glass? Glass production process includes: composition, melting, forming, annealing and other processes. According to the design of good material surface, all kinds of raw materials are weighed in the mixer and then evenly mixed. The main raw materials of glass are: quartz sand, limestone, feldspar, soda ash, boric acid, etc. 2. Melting. The prepared raw materials are heated at high temperature to form uniform bubble free glass. This is a very complex physical and chemical reaction process. The melting of glass takes place in a furnace. There are two main types of melting furnaces: one is a crucible kiln, in which the frit of the crucible is heated outside the crucible. Only crucibles are put in the small crucible kiln, which can be larger than 20 crucibles. Crucible kilns are produced by gaps, and now only optical glass and tinted glass are produced in crucible kilns. The other is a tank kiln in which the frit is melted and the glass fired on the upper surface is heated. The melting temperature of glass is about 1300-1600 ℃. Most of the heat is heated by a small amount of current with the flame, which is called a furnace. Now, the tank kiln is continuous production, a small tank kiln can be several meters, large can be as large as 400 meters 2.3. Molding, is to melt a good glass into a solid shape of solid products. Molding must be carried out within a certain temperature range. This is a cooling process. The first glass changes from a viscous liquid to a plastic, and then to a brittle solid.

Molding methods can be divided into two types: artificial molding and mechanical molding.

A. Artificial forming. And (1) blowing, using nichrome blowing pipe, selecting a cup of glass on the side of the mold at the blowing edge. It is mainly used to form glass bulb, bottle, ball (with glasses), etc.

(2) After drawing and blowing in small bubbles, another worker uses the roof bar, and the side blowing is mainly used to make glass tube or rod.

(3) Suppress, pick a piece of glass, cut it with scissors, make it fall into the mold, and then press a pressure. It is mainly used for forming cups, plates, etc.

(4) Free form, using pliers, scissors, tweezers and other tools directly into the arts and crafts. B. Mechanical molding. Due to the high labor intensity, high temperature and poor conditions of artificial molding, most of them have been replaced by mechanical molding except for free forming. In addition to pressing, blowing and drawing, there are (1) calendering method, which is used to produce thick flat glass, carving glass and folding line glass.

(2) Casting method, production of optical glass.

(3) Large diameter glass tube, tableware and large capacity reactor are manufactured by centrifugal casting. This is the high-speed rotation of the glass melt into the mold. The centrifugal force makes the glass against the mold wall, and the rotation continues until the glass is so hard.

(4) foam glass produced by sintering process. It is added foaming agent into glass powder and heated in the covered metal mold. A large number of closed bubbles are formed in the heating process of glass, which is a very good insulation and sound insulation material. In addition, flat glass is formed by vertical stretching method, flat drawing method and float method. Float is a method that allows glass flow to float on the surface of molten metal (TIN) to form flat glass. The main advantages are high glass quality (smooth), fast drawing speed and high output. During annealing, the glass undergoes strong temperature changes and shape changes during the formation process, and this change leaves thermal stress in the glass. This thermal stress will reduce the strength and thermal stability of glass products. If it is cooled directly, it can be broken by itself in the process of cooling or storage, transportation and use (commonly known as cold glass). In order to eliminate the phenomenon of cold explosion, glass products must be annealed after forming. Annealing insulation in a certain temperature range or slowing down for a period of time to eliminate or reduce the thermal stress in the glass to allow this value.