Aluminum sheets used in buildings include single-layer aluminium sheets, composite aluminium sheets and other materials, usually referring to single-layer aluminium sheets (also known as single-layer aluminium sheets or pure aluminium sheets), which are mostly used in architectural decoration projects. In recent years, single-layer aluminium sheets are commonly used in aluminium sheet curtain walls. Aluminum plate curtain wall is also a form of curtain wall. Simply speaking, it is made of aluminum plate instead of glass. Aluminum plate curtain wall is mostly used as wall shelter and wall without lighting.
The aluminum sheet curtain walls abroad have been selected for single layer aluminum plates. Single layer aluminum plates are usually made of pure aluminum plates. The thickness of aluminium sheet is 3 mm. In order to strengthen the strength of aluminium sheet, reinforcement bars must be installed on the back of the aluminium sheet (the existing manufacturers are uneasy). The reinforcement bars are made of thick aluminium strips. First, a screw cap is welded on the back of the aluminium sheet by flash welding machine, and then the aluminium bars drilled as reinforcement bars are inserted into the screw and fixed by the screw.
In order to reduce the weight of aluminium sheet and increase the strength of aluminium sheet, aluminium sheet is used in our country. Aluminum sheet pressed by No. 21 anti-rust aluminium code LF21 is often used as curtain wall aluminium sheet. The thickness of aluminum plate is reduced from 3mm to 2.5mm, which is twice as high as that of pure aluminum sheet. LF21 aluminium strip is used for reinforcing bars. The width and thickness of the strip depend on the surface of the aluminium plate. Generally, the thickness is 2-2.5mm and the width is 10-25mm. The reason why reinforcement should be installed on the back of aluminium plate curtain wall is that under positive and negative external pressure, the aluminium plate will not sink or bulge out, thus avoiding the vibration sound caused by repeated internal and external vibration of aluminium plate curtain wall. If sound insulation is needed, the rock can be placed on the inside of the aluminum sheet, with rock wool, slag wool or foam treatment.
Surface treatment of aluminium curtain wall can be divided into two methods, one is anodic oxidation, the other is electrostatic spraying. Anodized oxide film is generally more than 12 mu. The color is only bronze and white. The color is monotonous. The more serious disadvantage is that the color of each aluminium panel is different. Many curtain panels are combined to form a curtain wall with a very ugly overall effect. This disadvantage can not be eliminated, not caused by production technology, but because the aluminium plate is not a batch number, chemical composition, there are small differences, coupled with the oxidation of electrolyte current density and other factors can not be exactly the same, so the number of color after oxidation is different, single sheet may not be obvious, if all. That is very obvious. Therefore, the surface treatment of aluminum plate curtain wall must not be anodized.
Another way of surface treatment of aluminum curtain wall is electrostatic spraying. Spraying is divided into powder spray and liquid spray. Powder spraying materials are mainly polyurethane, swelling resin, epoxy resin and other raw materials with high color retention pigments, dozens of different color spraying powder can be obtained. The spraying powder, impact resistance and abrasion resistance, under the impact of 50 kg, the aluminum plate deformation, spraying coating without cracks, no layer dropping intact and non-destructive, anti-dilute acid and mortar. The only shortcoming is that the long term exposure to ultraviolet radiation will lead to differences in color between yin and Yang after a few years. The spraying powder produced by many domestic manufacturers has a great difference in weight. Some of them contain gold dust. After hanging on the wall, the powder changes with the angle of sunshine during the day and at dusk, and the color of the wall is different. The choice of powder spraying paint is expected to attract attention.