Raw material selection and production control of t

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Raw material selection and production control of low radiation coated insulating glass preface []

according to statistics, the energy lost by buildings through windows accounts for more than 30% of the energy consumed by buildings. With the development of the national economy, the country has higher and higher requirements for the environment, energy conservation and other issues. Since the implementation of the "design standard for energy efficiency of residential buildings", it is far from enough to adopt the traditional single-chip glass to achieve the goal of 65% energy saving in new houses. The U value of ordinary single-layer glass window is 6. About 0w/m2 · K, the U value of single frame double glass steel plastic composite window is 3. About 5 w/m2 · K, the U value of the window should reach 2. Low radiation insulating glass must be used below 5 w/m2 · K. A large number of practices at home and abroad have also proved that improving the thermal insulation performance of building envelope, especially the thermal insulation performance of windows, is the most economical and effective way to prevent heat loss of buildings. The energy-saving low radiation coated insulating glass with heating in winter and air conditioning and refrigeration in summer is the inevitable trend of development. With the extensive application of energy-saving insulating glass, its quality has been put on the agenda. There are two main factors affecting the quality of insulating glass: (1) the selection of raw materials; (2) Quality control of production process

1。 Selection of insulating glass raw materials

insulating glass [3] at present, there are three main types of insulating glass in China [4]: (I) groove aluminum single channel seal; (2) Slot aluminum double seal "do you need a bag? Small bag with 2 corner seals; (III) Compound sealant strip insulating glass. Trough aluminum single channel seal, due to its poor sealing performance, easy to enter moisture, resulting in glass condensation, frosting, and short service life, so this kind of insulating glass is gradually eliminated. The raw materials of the latter two kinds of insulating glass are mainly glass, aluminum strip, corner socket, butyl rubber, two-component polysulfide glue or silicone cave glue, desiccant and composite sealant strip. The quality of raw materials will directly affect the quality and service life of insulating glass. The precautions for the selection of raw materials are briefly described as follows: it is a product in which two or more pieces of glass are evenly separated by effective support, the value indicated by the passive pointer on the indicating dial (the displayed value of the digital display device) is read and sealed, so that a dry gas space is formed between the glass layers

1。 1 Selection of glass

the original glass can be float glass, laminated glass, tempered glass or semi tempered glass, coated glass, colored glass, embossed glass, etc. Float glass shall comply with gb11614, laminated glass shall comply with gb9962, tempered glass shall comply with gb/t9963, and coated glass shall comply with GBT 18915[1]. Provisions for coated glass

1。 2 selection of sealant

1. 2。 1 butyl adhesive: butyl adhesive is the first seal of aluminum strip insulating glass. It is a kind of hot melt adhesive with low water vapor transmission and high viscosity. It is the most effective barrier to block water vapor between the side of aluminum strip and glass, but it needs to be heated, pressurized, extruded and coated on both sides of aluminum strip by special machine. At present, there are many domestic butyl rubber brands, but the properties of each rubber such as heating temperature and pressure are different, which requires users to choose the best

1。 2。 2 polysulfide adhesive: polysulfide adhesive is the largest amount of insulating glass sealant at present. It has good oil resistance, solubility resistance and sealing performance. Polysulfide adhesive should have metal oxide as curing agent to polymerize. It is generally two-component. First, it must be reasonable to confirm the dimensional tolerance of plastic parts formed by different plastics. The ratio of the two components is about 1:10, which can be applied by machine or by hand. Selection requirements: clear color difference between two components; Good fluidity and curing elasticity; Strong UV resistance; Valid for more than half a year

1。 2。 3 silicone sealant: it has structural, aging resistance and UV resistance, but its fatal weakness is high water vapor transmission. It is suitable for places with strong light and poor environment. At the same time, butyl rubber must be used as the leading seal. It shall comply with the provisions of the industry standard (JC) of insulating glass sealant. Ordinary silicone glue is widely used to make insulating glass, which may lead to oil leakage, which is caused by the migration of silicone glue plasticizer after a period of time. Silicone oil will melt the lead sealing butyl glue, causing butyl glue to flow, affecting the appearance, and even causing the failure of insulating glass. Attention should be paid to the selection

1。 3. The selection of aluminum strip spacer and corner

the thickness of aluminum strip should be 0.. Between 35mm, the thickness should be uniform, and the vent holes should be evenly distributed. Aluminum strips need to be anodized or decontaminated and bent. Products with good quality and high grade must be selected to improve the utilization rate of aluminum strips

the corner size should be selected and the surface should be cleaned

1。 4 desiccant

there are three kinds of desiccants commonly used for insulating glass: 1. Those with good absorption capacity of volatiles; 2. The adsorption capacity of inert gas is the lowest; 3. Ordinary molecular sieve. Users should choose the appropriate molecular sieve according to their actual situation, and the molecular sieve should also have the appropriate particle size (. 5mm) and hardness. In addition, the environment where molecular sieves are used should be dry, and the filled molecules should be used within one hour to ensure the quality of insulating glass

1。 5 composite sealant strip

the adhesive strip is a raw material of insulating glass that integrates the support framework (wavy aluminum strip/stainless steel strip), sealing (butyl rubber) and drying (desiccant). Its biggest advantages are simple operation process, less waste of raw materials, less personnel, low management cost and good operating environment. The disadvantage is that the adhesive strip absorbs moisture slowly, so special equipment is required. At present, the price of adhesive strips is relatively high due to output constraints. The selection of composite sealant strips should consider the smooth surface, the quality of aluminum strip, the content of adhesive, and the moderate viscosity

2。 Production process control of low radiation insulating glass []

last year, the China Standardization Commission standardized the production process control of insulating glass and will form a formal industry production standard. For manufacturers, it is imperative to standardize the production process control of insulating glass and strengthen the training of operation details. How to ensure and improve the quality of insulating glass products will become an effective competitiveness for manufacturers to improve their product brands and occupy the market. This part analyzes the main factors affecting the quality of insulating glass in the production process, and hopes that the relevant production control personnel can learn from it and take effective measures to prevent it in time, so as to ensure the appearance and performance quality of insulating glass products

the process flow of insulating glass, including loading, membrane removal, cleaning, upper frame, lamination, glue sealing, and unloading, as well as the production processes such as adding elbows, filling molecular sieves, and coating butyl glue. The technological process is complex, and qualified products depend on the strict control of each production link

2。 1 glass cutting and blanking

the original piece of glass must comply with the provisions of relevant standards and can be used only after passing the inspection. Glass cutting can be carried out by hand or machine, but it should meet the size requirements. During the operation of this process, workers should always pay attention to the fact that the glass surface should not be scratched, the internal quality should be uniform, and there should be no obvious defects such as bubbles and slag inclusions

2。 2. Glass cleaning and drying

machine cleaning must be used for glass cleaning. Before cleaning, check whether the glass is scratched. In order to ensure the adhesion between sealant and glass, it is best to use deionized water. The cleaned glass shall pass the light inspection to check whether there are water drops, water stains and other stains on the surface of the glass. If there are water drops, water stains and other stains, the running speed, heating temperature, air volume and brush clearance of the machine shall be adjusted until the effect is perfect. The washed glass shall be assembled into insulating glass within 1 hour. In addition, it is necessary to ensure that there is no friction and scratch between the glass and the glass. It is best to have a semi-finished glass storage car to separate the glass pieces

after the sealed insulating glass is placed on the A-frame, its overall appearance quality should be inspected again: the uniformity of the mixing of the insulating plastic, whether there is empty glue, bubble glue, old glue; Whether the joint between hollow rubber and butyl rubber is good, whether there is a dotted line, etc. Check whether the surface dryness of the hollow adhesive is uniform after curing for three hours, and comprehensively check whether the curing degree is qualified after eight hours

whether the low radiation insulating glass is placed correctly or not will also have an impact on the final quality of the insulating glass. Whether it is in production, transportation or storage at the construction site, the design requirements of the stacking frame should first take into account the characteristics of the insulating glass, and the stacking frame should have a certain inclination. However, the bottom plane and the side should always be kept at 90 degrees, so as to ensure that the bottom edges of the two pieces of insulating glass can be placed vertically on the stacking frame. In addition, it should be noted that the bottom of the glass should not be stained with oil stains, lime and other compatibilizers, because they will erode the second sealant of the insulating glass to varying degrees, thus affecting the sealing performance of the insulating glass

3 summary

the quality assurance of insulating glass is that the quality of raw materials should be guaranteed, and the second is the strict and standardized production process quality control. Details determine success or failure, that is, in every processing link, we should pay close attention to the factors that may affect the appearance of materials and the performance of hollow structures, so as to take effective measures to avoid operational errors and improper operations. Only in this way can the quality of hollow glass products be guaranteed. Advanced production equipment, strict product quality standards and standardized management system should produce first-class products

the quality of low radiation insulating glass is the key to building energy conservation. If it fails, it will not play the role of energy conservation. Customers can according to their own needs. Generally speaking, we should constantly improve the processing technology of low radiation insulating glass, strive to improve the technical level and product quality, and promote the development of low radiation insulating glass to a higher, newer and stronger direction

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