Technology and processing method of the hottest dr

Technology and processing method of dry laminated glass

definition of laminated glass: laminated glass is a glass product made of a layer of glass and one or more layers of glass and plastic materials sandwiched between layers

classification of laminated glass: a) plane laminated glass; B) Curved laminated glass

thickness deviation of dry laminated glass

the thickness deviation of dry laminated glass cannot exceed the sum of the allowable deviation of the thick sheet constituting the laminated glass and the allowable deviation of the intermediate layer. When the total thickness of the intermediate layer is less than 2mm, the allowable deviation will not be considered. When the total thickness of the intermediate layer is greater than 2mm, the allowable deviation is ± 0.2mm

with the progress of society and the increasing improvement of people's living standards, people are no longer satisfied with the use of ordinary glass, and the deep processing industry of glass is becoming more and more developed

secondary glass products, namely deep processed glass, are glass products with specific functions made of once formed flat glass (float glass, ordinary lead flat glass, flat glass, calendered glass) as basic raw materials and different processing processes according to the use requirements. The commonly used laminated glass products are made of float glass

laminated safety glass is made of plastic materials such as polyvinyl butyral (PVB) intermediate film, polycarbonate board, polyurethane board and acrylate board sandwiched between two or more layers of glass and processed under high temperature and high pressure. The commonly used intermediate material of laminated glass products is polyvinyl butyral (PVB) film

pvb film has good adhesion, toughness and elasticity. In order to provide customers with this kind of experience when laminated glass is violently impacted by external forces, the film will absorb a lot of energy, and the glass fragments will firmly adhere to the PVB intermediate film, so that the glass fragments will not fly away, so as to minimize the possible damage. Laminated glass has good security, noise reduction, sunlight control and UV protection characteristics. According to the needs, ordinary float glass, tempered glass, Low-E glass, etc. can be selected as the original sheet of laminated glass, so that the laminated glass has different properties

compared with glass products, laminated safety glass mainly has the following functions:

(1) improve the strength of glass and enhance the safety of glass

(2) change the shape of flat glass

(3) treatment of glass surface

glass surface treatment includes two aspects:

a) enrich the glass surface, that is, use physical or chemical methods to make different patterns and patterns on the glass surface

b) refers to the coating treatment of the glass surface

there are two forms of laminated glass production: dry (Class A) and wet (class B). At present, the dry production of laminated glass with (Class A) P and life VB diaphragm is the mainstream

today's glass deep processing business is characterized by fixed single frequency, many types, short cycle and fast delivery. Such production mode has higher requirements for glass processing equipment. Glass deep processing equipment must be able to meet the needs of mixed production and have high flexibility

this article mainly exchanges the international common way in glass deep processing:

(Class A) production method and process of dry laminated glass:

raw materials and equipment of laminated glass:

high quality float glass: 3 ~ 22mm,

polyvinyl butyral (PVB) film:

0.38mm0.76mm1.14mm

glass washing and drying machine flat pressing primary press glass autoclave arc glass pre press

the combination of multilayer tempered glass and multiple pieces of PVB film is to enhance the bulletproof and anti-theft performance of laminated glass. The thickness of glass and PVB increased. Because the glass and PVB film are bonded very firmly, they almost become a whole; And because the glass has high hardness and the PVB film has good toughness, when the bullet contacts the laminated glass, it absorbs its impact kinetic energy through the elastic deformation of the diaphragm until the impact energy is weakened to a low degree or even zero, so it cannot penetrate. Similarly, the impact of metal can only break the glass and cannot penetrate, so it has the effect of bulletproof and anti-theft

1. Cutting, cleaning and processing of glass:

when cutting, the cutting mark of the original sheet should be appropriate to obtain a good edge stripping effect. The size should be accurate, and no difference greater than 2mm is allowed, so as to avoid bubbles due to uneven edges. After cutting, the edge of the glass should be ground and then cleaned with a film washer. After cleaning, the glass surface must not be left with oil and other debris. The cleaned glass can be used only after it is dried and placed at room temperature

2. Lamination:

lamination should be carried out in the lamination room that meets the process requirements:

(1) the cleanliness must be high, and the cleanliness should be purified to 100000

(2) staff should have clothes and tools suitable for purification conditions

(3) the room temperature of the composite is 25 ℃ and the relative humidity is about 25%

(4) the upper and lower glass interlayer should be aligned, and the stacking difference should not exceed about 1.5mm

(5) keep clean between PVB film and glass interlayer

in the laminating room that meets the process requirements, after the glass is placed horizontally, lay the PVB intermediate film on the glass and lay another piece of glass. Trim and cut the PVB intermediate film with a knife. When trimming, do not pull the PVB intermediate film forcibly to avoid the deformation of the PVB intermediate film, and ensure that the margin of the PVB intermediate film outside the glass is within the range of 2-5mm. When trimming, the blade must not be in contact with the glass, so as to prevent the glass particles produced from causing bubbles at the edge after processing

carry out high-speed mixing. 3. Pre press and exhaust:

the combined glass must be pre pressed and exhaust to exhaust the residual air between the glass and the PVB intermediate film interface, and obtain a good edge banding effect before high-pressure molding

there are two methods for prepressing and exhaust:

A. rolling and exhaust method:

processing equipment: flat primary press

after cleaning and drying, the glass is automatically transmitted into the input end of the equipment after the composite film is driven by it, and smoothly enters the prepressing roll for uniform rolling, removes the initial part of the air, and enters the prepressing and heating oven for prepressing and heating, so that the film reaches the required fusion temperature. After the glass and the film have been in good contact, The transfer roller in the heating box will input it into the final pressing roller for uniform rolling, so that the glass and film are fused into one, and then output from the output section. The glass and film are firmly bonded together, and almost transparent. In this way, the work of flat laminated glass is completed at one time, and then it is ready for final processing in the autoclave

the closed glass enters the roller press, is extruded by the leading roller, enters the incubator, and then is extruded by the second roller, and the process is completed by exhaust and edge banding. After the second roll is out, a whole circle of transparent tape should be presented around the laminated glass to seal the edge, so as to avoid the gas backflow in the autoclave to produce bubbles. Other parts can have evenly distributed opaque parts. This process requires that the temperature of the glass surface must be strictly controlled, not to be too high, so that the edge sealing is premature, and the internal gas cannot be discharged; The temperature should not be too low, and the edge banding is not complete, resulting in reflux bubbles

suggestion: the composite materials on the preheated surface of the combined glass are mainly the agricultural and forestry wastes in our province. The temperature is about 20-25 ℃. The gap between the leading rubber rollers should be about 1mm smaller than the total thickness of the laminated glass, and the pressure is about 0.2 – 0.5MPa. The gap of the second rubber roller should be about 2mm smaller than the total thickness of laminated glass, and the pressure should be about 0.4 – 0.6MPa. When entering the second roll, the glass surface temperature must be strictly controlled at about 60-80 ℃. The glass products to be processed shall be prepared first during production, and the production shall be carried out continuously as far as possible, so as to avoid that the glass surface temperature cannot be accurately controlled due to the long interval and excessive temperature change of the incubator

advantages of rolling exhaust method: continuous production, high output and energy saving

b, vacuum preloading and exhaust method:

processing equipment: arc glass pre press

put the laminated glass into the vacuum bag or put a vacuum rubber ring around it. After cold pumping and hot pumping, use the pressure difference to exhaust the air in the glass/PVB intermediate membrane interface and seal the edge

suggestions: the vacuum degree of decompression is more than 650mmhg, the cold pumping temperature is about 25 ℃, and the cold pumping time is more than 20 minutes; The surface temperature of the glass needs to reach 70-120 ℃ for more than 40 minutes during hot pumping. Zhonghua glass () Department