[China Glass Network] 1. Classification and difference of energy-saving glass: (The following contents refer to JGJ134-2001 "Summer and Hot Winter Energy Saving Standard") Energy-saving glass is divided into two parts: heat reflection and Low-E. The heat reflection and Low-E glass processing are the same. They are produced by vacuum magnetic sputtering. The difference is that the two are The surface of the glass is plated with different metals. The heat reflection is mainly coated with metal oxides, nitrides, etc., while the surface of the Low-E glass is coated with a layer of metallic silver in addition to metal oxides and nitrides. Silver is the emissivity. A very low metal, so Low-E glass has a very low U value in addition to its better reflection of solar radiation than heat reflective glass. As can be seen from the above figure, in the case where the visible light (0.38-0.78 μm) transmittance is substantially the same, the infrared (0.78-2.5 μm) transmittance of several coated glasses is significantly different. The infrared transmittance of the heat-reflecting glass is still high, the single-silver Low-E glass is significantly reduced, and the double-silver Low-E is lower, and the three-silver Low-E is lower, so the Low-E glass is more energy-efficient! The energy-saving effect of heat-reflecting glass can only be manifested during the summer day when there is strong solar radiation. In the case of the solar radiation intensity in winter is small, or there is no solar radiation at night, the heat-reflecting glass has the same effect as ordinary glass. Low-E glass can play an energy-saving role in summer or winter, day or night, because far-infrared radiation is commonly found in the environment. Therefore, compared to the heat-reflecting glass, the energy-saving area range, time span and effect of the Low-E glass are better than the heat reflection. 2. Performance comparison of energy-saving glass: The above table is a comparison of the performance parameters of energy-saving glass and ordinary glass. It can be seen from the table that the U value of the heat-reflecting glass is very different from that of ordinary glass, but the shading coefficient is low, and the Low-E glass has a lower shading coefficient. In addition, the U value also drops to a very low level. The selection coefficient in the latter column refers to the ratio of the visible light transmittance to the shading coefficient, that is, r=T/Sc. For glass, people always want visible light to enter the room as much as possible, thus improving the lighting effect, and hope that the sunshade coefficient is as low as possible, and the sunshade can reduce the solar radiation entering the room, thereby improving the living environment in the summer room. Therefore, from the perspective of comprehensive performance, when designing domestic and foreign buildings, glass with a high selection coefficient should be adopted as much as possible. At present, domestic and foreign manufacturers are developing 3 silver Low-E glass, mainly because the three silver Low-E glass can increase the visible light transmittance while reducing the shading coefficient, thereby filtering the hot solar radiation source into cold. light source. The price of 6LOW-E+12A+6 glass is as follows: double tempered structural adhesive is around 230 yuan/m2, double silver is around 260 yuan/m2, and three silver is around 290 yuan/m2. 3. Application of energy-saving glass: In the application of glass, from the perspective of energy saving, three main aspects are considered: visible light transmittance T, shading coefficient Sc, heat transfer coefficient U. Wuxi is located in hot summer and cold winter areas. It is hot in summer and requires a low shading coefficient Sc and a heat transfer coefficient U value. In winter, the shading coefficient is not high, but the heat transfer coefficient should be as low as possible. Today's buildings have strong requirements for lighting effects. Therefore, many windows are designed with large bay windows, combination windows or floor-to-ceiling windows. The window wall area ratio is 0.3 or even 0.5. This design can improve the lighting effect. However, the disadvantage is that the heat transfer coefficient is large, especially for aluminum alloy windows. If ordinary hollow glass is used, it will not reach the standard in most areas of hot summer and cold winter. If it is replaced by a broken aluminum window, Considering the optimization of window type and reducing the area ratio of window and wall, it can meet the requirements of some areas! That is to use plastic steel window, for the combined window with window area ratio greater than 0.35, ordinary insulating glass can not meet the requirement of U value ≤ 2.5, and because of plastic The surface area of ​​the profile is relatively large, which will significantly reduce the lighting effect! Therefore, Low-E glass can be selected to reduce the performance of lighting and heat preservation by reducing the separation of the combined window, and the large-area glass can greatly improve the visual effect. The thermal conductivity of the insulating glass is about one and a half lower than that of a single piece of glass, which is mainly the function of the gas spacer. In addition to the air, the gas filled in the hollow glass has an inert gas such as argon gas or helium gas. Since the thermal conductivity of the gas is very low (air 0.024 W/mK; argon 0.016 W/mK), the thermal resistance of the insulating glass is greatly improved. The 6+12+6 white glass hollow combination has a K value of about 2.7 W/m2K when filled with air, a K value of about 2.55 W/m2K when filled with 90% argon, and about 2.53 when filled with 100% argon. W/m2K, K value is about 2.47W/m2K when filled with 100% helium. Compared with the two inert gases, argon is rich in air, easy to extract, and low in cost, so it is widely used. Regardless of the gas to be filled, the SHGC value and the visible light transmittance of the insulating glass remain substantially the same at the same thickness. The commonly used hollow glass spacer layer has a thickness of 6 mm, 9 mm, 12 mm, and the like. The thickness of the gas spacer is directly related to the size of the heat transfer resistance. In the case where the glass material and the sealing structure are the same, the larger the gas spacer layer, the larger the heat transfer resistance. However, after the thickness of the gas layer reaches a certain level, the growth rate of the heat transfer resistance is small. Because when the thickness of the gas layer increases to a certain extent, a certain convection process will occur under the action of the temperature difference between the gases, thereby reducing the effect of thickening of the gas layer. As shown in Fig. 4, when the gas layer is increased from 1 mm to 9 mm, the K value decreases by 37% when the white glass is filled with air, the K value decreases by 53% when the Low-E hollow glass is filled with air, and 59% when the argon gas is filled. When increasing from 9mm to 13mm, the descent speed begins to slow down. After 13mm, the K value has a slight rebound. Therefore, for a 6 mm thick glass hollow combination, the increase in the thickness of the gas spacer layer exceeding 13 mm does not produce a significant energy saving effect. 4. Reasons for choosing energy-saving glass: “Saving energy is saving money, and it saves a lot.†According to the empirical data of the German Door and Window Curtain Wall Manufacturers Association, the U value is reduced by 0.1, and every square meter of window can save 1.2 liters of heating oil per year, which is equivalent to about 12 degrees of electricity; therefore, by reducing the U value, it can be used during the life of the window. Save a lot of air conditioning and heating costs. For example, the ordinary hollow glass U value is calculated according to 2.8, the single silver Low-E hollow glass U value is calculated as 1.8, after folding into the whole window, the U value can be reduced by about 0.6-0.8, (calculated here, 0.7), the insulating glass is 20 years. The service life, then 20 yuan per square meter of window can save about electricity: (0.7 / 0.1) × 12 × 20 = 1680KWh. This money can be saved, you can buy several square meters of high-performance Low-E glass, and can greatly save energy and reduce carbon dioxide emissions. Knitting Fabric,Soft Knit Fabric,Fabrics For Clothing,Polyester Knit Fabric Shaoxing Linkloom Import and Export Co.,ltd. , https://www.linkloomtextile.com