What are the quality control methods for aluminum veneer

The quality of aluminium plate directly affects the quality of the entire curtain wall, so the quality control of the procurement of the panels is the key.

The aluminum veneer generally uses pure aluminum. The thickness of the aluminum veneer commonly used in exterior walls is generally 2.5-3mm. In order to strengthen the surface strength of the aluminum veneer, reinforcing ribs must be installed on the back of the aluminum plate. The reinforcing ribs are made of thick aluminum tape (the reinforcing ribs of the plate Are located at different heights to calculate their size), first use a flash welder to weld the screw caps on the back of the aluminum plate, then drill the aluminum strip as the reinforcing rib into the screw and fix it with the screw. Reinforcing ribs should be installed on the back of the aluminum panel of the aluminum panel curtain wall. The reason is that under the condition of positive and negative external pressure, the aluminum panel will not sag and will not bulge out. This avoids the vibration sound of the aluminum panel curtain wall repeatedly vibrating inside and out.

If sound insulation is required, rock wool, slag wool or foaming treatment can be placed inside the aluminum plate. Domestic aluminum plate manufacturers can produce various widths and lengths and various arc-shaped special-shaped curtain wall aluminum plates according to user requirements, and weld the reinforcing ribs. The installation of stiffeners is also very important. The stiffeners of some manufacturers are not effectively connected to the folding edge of the aluminum plate, which destroys the force transmission function of the strengthening rod, and causes deformation of the plate after use, which affects the facade effect.

In order to reduce the weight of the aluminum plate and increase the strength of the aluminum plate, the aluminum alloy plate we use often chooses the aluminum plate made of No. 21 anti-rust aluminum (code LF21) as the curtain wall aluminum plate. The thickness of the aluminum plate is reduced from the original 3mm to 2.5mm, and the strength of the alloy is about twice as high as that of the pure aluminum plate. Due to the relatively small aluminum content of the aluminum alloy plates used by individual manufacturers, the plates produced are rusty or cracked, which seriously affects the quality. The synthetic composition of the board must meet the standard.

The surface treatment of curtain wall aluminum panels can be divided into two methods, one is anodizing and the other is electrostatic spraying. The anodized oxide film is generally above 12μ, and the color is only two kinds of bronze and white. The color is monotonous. The disadvantage is that the color of each aluminum plate is different. The overall effect of the curtain wall formed by the combination of many curtain wall panels is very ugly. This shortcoming can be said to be impossible to eliminate. It is not caused by the production technology, but because the aluminum plate is not of the same batch number, the chemical composition is small, and the current density of the electrolytic bath during oxidation cannot be completely the same, so the oxidized The colors are somewhat different. It may not be obvious from a single sheet, but it is very obvious if they are all lined up together. Therefore, the surface treatment of the aluminum plate of the aluminum plate curtain wall must not be anodized.

Another method of surface treatment for curtain wall aluminum panels is electrostatic spraying. Spraying is divided into powder spraying and liquid spraying. Powder spraying materials are mainly: polyurethane, swelling resin, epoxy resin and other raw materials are matched with high color retention pigments, and dozens of different colors of spraying powder can be obtained. The sprayed powder is resistant to collision and abrasion. Under the impact of 50 kg, the aluminum plate is deformed, the sprayed layer has no cracks, no layer drop, intact, and is resistant to dilute acid and mortar. The only disadvantage is that it is afraid of long-term exposure to ultraviolet rays, and the color of the yin and yang may be different after a few years. The spray powder produced by many domestic manufacturers has great weight differences. Some powders contain gold chips. After this powder is hung on the wall, it changes with the angle of sunlight during the day and dusk, and the color of the wall is different. Attention should be paid to the selection of powder spray paint.