The application of metal plate curtain wall has a history of several decades, and it is still in use, including aluminum veneer, aluminum plastic composite panel and aluminum honeycomb panel. Among these three materials, aluminum veneer and aluminum-plastic board are commonly used. Aluminum veneer appeared early, and then in the late 1960 s and early 1970 s, aluminum-plastic composite panels were invented in Germany and quickly became popular all over the world. In this Eastern European aluminum veneer manufacturers will make a simple comparison of these two materials:
1. materials and cost
Aluminum veneer generally adopts AA1100 pure aluminum plate with a thickness of 2-4mm or AA3003 and other high-quality aluminum alloy plates, while AA3003 aluminum alloy plate with a thickness of 2.5mm is generally used in China. Aluminum-plastic composite plates generally adopt a 3-4mm three-layer structure, including upper and lower 0.5mm sandwiching PVC or PE. We can see from the material, the cost of aluminum-plastic composite panels must be much lower than the aluminum veneer. The market is about 4mm thick composite board than 2.5mm thick aluminum veneer price is lower than 120 yuan/square, a 10,000 square project, the use of aluminum-plastic board than the use of aluminum veneer cost 1.2 million yuan.
2. machining process
There are two kinds of aluminum veneer in the world: fluorocarbon sprayed aluminum veneer and roller coating. There is no roller coating production line in China for the time being, so the processing process of veneer here is mainly about fluorocarbon spraying production. Spray production of aluminum veneer is divided into two steps: the first step is sheet metal processing. This process is mainly through the flat through cutting, folding, bending arc, welding, grinding and other processes, the aluminum veneer is processed into the shape and size required for construction. The second step is spraying. Spraying is spraying paint on the processed sheet metal. There are two kinds of spraying, one is manual spraying and the other is machine spraying. Machine spraying is generally only suitable for regular flat plates, but this kind of aluminum veneer is less used in actual use, and most domestic manufacturers use manual spraying. Artificial spraying is a dangerous job, because the volatile and toxic paint are relatively strong, it is easy to cause chronic benzene series poisoning, seriously affecting human health. One of the great advantages of artificial spraying is that regardless of the size of the amount, the color can be optional, and the roller coating of the aluminum-plastic plate must reach a certain amount before it can be processed. The processing process of aluminum-plastic plate is more complicated than aluminum veneer, mainly including four major processes: formation, coating, compounding and trimming. These four processes are all automated production except trimming. It can be seen from its processing process that aluminum-plastic panels have certain advantages in environmental protection and safety. Coupled with the simple sheet metal process of aluminum veneer, some private workshops have also begun to get involved, seriously affecting the stability of the market quality of aluminum veneer.
3. products
Item 2.5mm aluminum veneer 4mm thick aluminum plastic composite panel
Appearance quality flat flatness is not high, looks like a local bump, flat flatness is relatively high, but the processing shape is limited;
However, it can be processed into various irregular shapes. The quality of spraying roller coating is of good eye quality, color difference and film thickness deviation.
Due to the instability of manual technology, local color difference is not obvious, but the damage can not be repaired locally.
And film thickness deviation; local damage can be repaired.
Machine tensile strength 130/mm 38-61N/mm2X
Mechanical elongation 5%-10% 12%-17%
Bending strength 84.2N/mm 34N/mm2
Energy modulus of elasticity 70.00N/mm2 26.136-49.050N/mm2
It can be seen from the above table that the appearance of aluminum veneer is worse than that of aluminum-plastic plate, but its mechanical properties are obviously better than that of aluminum-plastic plate, and its wind pressure resistance is also better than that of aluminum-plastic plate. However, in most areas of our country, the wind pressure value of aluminum-plastic panels is completely bearable, so the use of aluminum veneer in engineering is a bit overkill.
4. construction process
The construction process of aluminum-plastic panels and aluminum veneer is roughly the same. The large aluminum-plastic plate is not processed into the required shape and specifications at the site, which has a greater degree of freedom in construction. The aluminum veneer is processed and formed by Chinese manufacturers. Due to the accuracy of domestic equipment, it often encounters some small troubles in the construction process. In addition, in terms of the guarantee of delivery time during the construction process, the mass production of aluminum-plastic composite panels is much faster than that of aluminum veneer, and the schedule guarantee system is also higher.
5. processing requirements
As a senior manufacturer, we must integrate scientific research, design and production. Senior manufacturers must first have an independent system, can quickly complete the basic design of products, have the corresponding scientific research capabilities, can improve product shortcomings and develop new products, solve problems encountered in reality, and then meet the requirements of production capacity. Sheet metal processing requirements: complete cutting, punching, bending and processing arc-shaped plate rolling machine, can realize the basic size of 4 meters of various complex shapes of sheet metal processing (many manufacturers can achieve more than 6 meters processing, but the longer the length, the worse the flatness). Argon arc welding and high-frequency nail welding equipment for aluminum can ensure the high-quality completion of the welding, angle sealing and stiffening nail processes of formed aluminum plates. Mechanized grinding and polishing equipment, 6.6 × 1.7 × 1 m automatic pretreatment tank and a set of 8 × 3 m and 8 × 2 m spray booth and oven designed and manufactured can complete the processing of oversized plates and long materials, it can ensure that the surface of the product meets the film requirements of the substrate required for coating.
Spray processing requirements: chemical pretreatment with chemical solution to remove organic and inorganic stains on the metal surface. Then remove the natural oxide layer, and then use chemicals to produce oxide film, so that the metal surface to produce rust and permanent paint adhesion. Electrostatic coating using domestic advanced automatic electrostatic spraying line, the fluorocarbon coating according to process requirements layer by layer spraying on the metal surface, and according to the specific temperature and time baking curing.
Quality assurance system requirements: quality inspection and packaging using high-precision special testing equipment for product quality strict inspection, to ensure that the product size accuracy to meet enterprise standards, film quality in line with the United States AAMA-605 standards.
6. other aspects
The issue of lightning protection characteristics has been debated for a long time. People have always thought that aluminum veneer is pure aluminum and has better conductivity. In response to this problem, the German ALUSUISSESINGEN GMBH has done lightning resistance experiments on two materials in a German military laboratory. The results show that in the instant impact of lightning strike, the curtain wall connection method adopted, whether it is aluminum-plastic plate or aluminum veneer, can completely prevent lightning strike; when the lightning strike continues, it is easy to melt at the lightning strike of metal plate or metal surface layer. The aluminum-plastic composite board due to the good insulation of the middle polyethylene core layer, lightning damage is limited to the skin, from this point of view, aluminum-plastic composite board than aluminum veneer has better lightning resistance.
2, fire characteristics of aluminum veneer is not burning, this is everyone knows. Early aluminum-plastic panels are not able to fire, but with the development of aluminum-plastic panel technology, the production of fireproof aluminum-plastic composite panels due to the addition of flame retardant materials in its PE, greatly improved fire performance, has been fully able to meet the needs of engineering fire.
3, the residual value of aluminum veneer has a certain residual value, but because of its high cost, compared to almost no residual value of aluminum-plastic composite panels, the waste is still much larger. In summary of the above analysis, aluminum veneer and aluminum-plastic composite panels have their own advantages, but from a large point of view, the application of aluminum-plastic panels should be more affordable and environmentally friendly.