Basic knowledge of the hottest architectural glass

Basic knowledge of architectural glass

glass is an amorphous inorganic material made of quartz sand, soda ash, feldspar and limestone through melting, molding, cooling and solidification. It has the transparency that ordinary materials are difficult to have, and has excellent mechanical and thermal properties. Moreover, with the development of modern architecture, it continues to develop in the direction of multi-function. Deep processed glass products can control light, adjust temperature, prevent dryness and improve architectural art decoration. Glass is no longer just a lighting material, but also a structural and decorative material of modern architecture

I. flat glass

flat glass refers to the adjustment of convenient detection position; The servo motor drives the precision lead screw to drive the loading actuator to move along the Z axis to realize the application of experimental force. Flat glass products without other processing, also known as white glass or clean glass. According to different production methods, it can be divided into ordinary flat glass and float glass. Flat glass is the most produced and used kind of architectural glass. It is mainly used for doors and windows, which plays the role of daylighting (visible light transmittance 85%90%), enclosure, thermal insulation, sound insulation, etc. it is also the original piece of glass further processed into other technologies

flat glass can be divided into window glass and decorative glass according to its purpose. According to the national standards "ordinary flat glass" (gb4871-1995) and "float glass" (gb11614-89), glass can be divided into the following specifications according to its thickness:

ordinary flat glass produced by drawing method: 2mm, 3mm, 4mm, 5mm

float glass: 3mm, 4mm, 5mm, 6mm, 8mm, 10mm and 12mm

the length width ratio of glass produced by drawing method shall not be greater than 2. 5. The size of 2 and 3mm thick glass shall not be less than 400mm × 300 mm, 4, 5 and 6mm thick glass shall not be less than 600mm × 400mm。 The size of float glass is generally not less than 1000mm × 1200mm, 5, 6mm up to 3000mm × 4000mm。

according to the national standard, flat glass is graded according to its appearance quality. Ordinary flat glass is divided into three grades: excellent products, first-class products and second-class products. Float glass is divided into three grades: excellent products, first-class products and qualified products. At the same time, it is stipulated that the bending degree of glass shall not exceed 0. 3%。

ordinary flat glass is measured by standard box, actual box and weight box. The thickness of 2mm flat glass is 1 standard box every 10m; For flat glass of other thickness specifications, standard box conversion is required. The actual box is the unit used to transport piece Lou. The thickness of glass is different, and the actual packaging volume of each box is also different. The number of standard cases can be obtained by multiplying the cumulative square of the same thickness by the thickness coefficient. Weight box refers to the weight of each standard box of 2mm thick flat glass, and other thick aromatic glass can be exchanged by a certain coefficient

the use of flat glass has two aspects: 3 ~ 5mm flat glass is generally directly used for the lighting of doors and windows, and 8 ~ 12mm flat glass can be used for partition. Another important use is as the original sheet of tempered, laminated, coated and hollow glass

II. Safety glass

safety glass refers to the glass with high mechanical strength and strong impact resistance compared with ordinary glass. Its main varieties are tempered glass, wired glass, laminated glass and titanium glass. When the safety glass is broken, its fragments will not hurt people, and it also has the functions of anti-theft and fire prevention. According to the original glass used in production, the safety glass has a certain decorative effect

(I) tempered glass

tempered glass is also called strengthened glass. It uses physical or chemical methods to form a compressive stress layer on the surface of the glass. The glass itself has high compressive strength and will not cause damage. When the glass is subjected to external force, this pressure layer can offset part of the tensile stress and avoid the fragmentation of the glass. Although the tempered glass is in a large tensile stress state, there are no defects inside the glass and will not cause damage, so as to improve the strength of the glass

tempered glass is the secondary processing product of flat glass. The processing of tempered glass can be divided into physical tempering method and chemical tempering method

physical tempered glass is also called quenched tempered glass. When the ordinary flat glass is heated to the softening temperature (600 ℃) of the glass in the heating furnace, the internal stress is eliminated through its own deformation, and then the glass is removed from the heating furnace, and then the high-pressure cold air is blown to both sides of the glass with a multi head nozzle, so that it can be quickly and evenly cooled to room temperature, and then the tempered glass can be made. This kind of glass is in a stress state of internal tension and external compression. Once local damage occurs, stress release will occur, and the glass will be broken into countless small pieces. These small pieces have no sharp edges and corners, and are not easy to hurt people

chemical toughened glass is to improve the strength of glass by changing the chemical composition of the surface of glass. Generally, ion exchange method is used for toughening. The method is to immerse silicate glass containing alkali metal ions into lithium (Li +) salt in the molten state, so that Na + or K + ions on the surface of the glass exchange with Li + ions, and a Li + ion exchange layer is formed on the surface. Because the expansion coefficient of Li + is less than Na + and K + ions, the outer shrinkage is small and the inner shrinkage is large during the cooling process. When it is cooled to room temperature, the glass is also in the inner tension, When the outer layer is under pressure, its effect is similar to that of physically toughened glass

tempered glass has high strength, and its compressive strength can reach more than 125mpa, which is 4 ~ 5 times larger than ordinary glass; The impact strength is also very high. When measured by the steel ball method, 0. 8kg steel ball from 1. The glass can be kept intact when falling at a height of 2m

the elasticity of tempered glass is much greater than that of ordinary glass, 1200mm × 350mm × 6mm tempered glass can have a bending deflection of 100mm after being stressed. When the external force is removed, it can still be restored to its original state, while the bending deformation of ordinary glass can only be a few millimeters

good thermal stability, and it is not easy to crack when subjected to rapid cooling and heating, which is another feature of tempered glass. This is because the compressive stress of tempered glass can offset part of the tensile stress caused by rapid cooling and heating. Tempered glass is resistant to thermal shock, and the maximum safe working temperature is 288 ℃, which can withstand the temperature difference of 204 ℃

tempered glass has been widely used in construction engineering, transportation and other fields because of its good mechanical properties and thermal stability. Flat tempered glass is often used for doors and windows, partitions, curtain walls, window displays, furniture, etc. of buildings, and curved glass is often used in automobiles, trains, aircraft, etc

when using, it should be noted that the tempered glass cannot be cut, ground, and the edges and corners cannot be impacted and extruded. It needs to be selected according to the ready-made size specifications or put forward specific design drawings for processing and customization. The toughening of glass used for glass curtain walls with very low specific gravity and large area shall be controlled. Semi toughened glass shall be selected, that is, its stress shall not be too large, so as to avoid self explosion caused by vibration caused by wind load. According to the original glass used, it can be made into ordinary tempered glass, endothermic tempered glass, cairan tempered glass, tempered hollow glass, etc

(II). Wired glass

also known as shatterproof glass or steel wire glass. It is produced by calendering, that is, when the glass is molten, the preheated steel wire or steel wire is pressed into the middle of the glass, annealed and cut. The surface of wired glass can be embossed or polished, and the color can be made colorless, transparent or colored

wired glass is characterized by good safety and fire resistance. Due to the skeleton effect of steel wire, the strength of the glass is not only improved, but also when it is damaged by impact or sudden temperature change, the fragments will not fly away, avoiding the damage of fragments to people. In case of fire, when the flame extends, the wired glass will be heated and burst. Due to the role of metal wires, the glass can still remain fixed and isolate the flame, so it is also called fire-proof glass

according to the national industry standard JC, the thickness of wired glass is divided into 6, 7 and 10mm, and the size is generally not less than 600mm × 400mm, not more than 2000mm × 1200mm。

at present, the wired glass produced in China is divided into wired embossed glass and wired polished glass. The wired glass can be used in the anti windows, skylights, daylighting roofs, balconies and other parts of buildings

(III) laminated glass

laminated glass is a flat or curved composite glass product made of PVB (polyvinyl butyral) resin film between two or more original glass sheets by heating and pressure bonding. The original sheet used for laminated glass can be ordinary flat glass, float glass, tempered glass, colored glass, heat absorbing glass or heat reflecting glass, etc

there are 2, 3, 5 and 7 layers of laminated glass, up to 9 layers at most. For two layers of laminated glass, the thickness of the original sheet is usually (mm): 2 + 3, 3 + 3, 3 + 5, etc. The structure of laminated glass is shown in the figure

laminated glass has good transparency and impact resistance several times higher than ordinary flat glass. It can be made into bulletproof glass by compounding multiple layers of ordinary glass or tempered glass. Due to the adhesion of PVB film, even if the glass is broken, the fragments will not fly and hurt people. By using different original glass, laminated glass can also have durability, heat resistance, moisture resistance and other properties

laminated glass has high safety, and is generally used in buildings as windows and doors, skylights, shop windows and partitions of high-rise buildings, banks, jewelry, etc

(IV) titanium glass

titanium glass is also known as never broken armor foil glass. It is a new type of glass that adheres titanium foil film to any kind of glass substrate and combines it into one. Titanium glass has high crushing resistance, high heat and UV protection and other functions. Different base glasses and different titanium foil films can be combined into titanium glass with different colors, different properties and different specifications. The common colors of titanium glass are: colorless transparent, tawny, tawny reflective, copper reflective, etc

III. energy saving glass

traditional glass is mainly used for lighting in buildings. With the increase of the size of building doors and windows, people's requirements for thermal insulation of doors and windows have been correspondingly improved. Energy saving decorative glass is a kind of glass that can meet this requirement and integrates energy conservation and decoration. Energy saving decorative glass usually has a pleasing appearance color, but also has special light and heat absorption, transmission and reflection capabilities. With the external wall window glass curtain wall of the building, it can play a significant energy-saving effect, and has been widely used in various high-grade buildings. Energy saving decorative glass commonly used in buildings includes heat absorbing glass, heat reflecting glass and insulating glass

(I) heat absorbing glass

heat absorbing glass is a flat glass that can absorb a large amount of infrared radiation and maintain a high visible light transmittance. There are two ways to produce endothermic glass: one is to add a certain amount of colouring agent with endothermic property to the raw materials of ordinary soda lime silicate glass; The other is made by spraying one or more layers of metal or metal oxide films on the surface of flat glass

the heat absorbing glass includes gray, Tan, blue, green, bronze, bronze, pink and golden yellow. At present, China mainly produces the first three colors of heat absorbing glass. There are four thicknesses: 2, 3, 5 and 6mm. Endothermic glass can also be further processed into polished, tempered, laminated or hollow glass

endothermic glass