The unevenness of the aluminum sheet is caused by 40% of the material and 60% of the construction. In fact, every aspect is indispensable.
main reason:
1. Deepening the design
- Folding size: The conventional folding size of the aluminum sheet factory is 20mm, but in the project design, due to the façade effects such as deep grooves, the designer usually directly widens the folding size, or even folds it several times. This will increase the accumulation of sheet deformation and increase the hidden danger of deformation during transportation and stacking.
- The specification and thickness of the aluminum sheet: according to the architect’s requirements for the effect of the facade, make a reasonable division. The short side of conventional sheets is 1220mm, and with the improvement in technology, it is now possible to prodsuce and process extra-wide sheets. The larger the sheet, the higher the sheet thickness, and the greater the flatness challenge.
- Surface treatment process and color system of aluminum sheet: For comprehensive projects, light colors (silver gray, white, champagne) have better flatness performance, while dark colors (dark coffee, black) are prone to unevenness. The unique stone imitation process reduces the gloss to about 30%, and proper rough surface treatment can form diffuse reflection and reduce direct sunlight.
2. Aluminum
Base material: 3003H24 series aluminum alloy.
Thickness: 2.5mm (no negative tolerance), thickened to 3mm and 4mm to help improve flatness.
3. Processing and transportation of aluminum sheets
1. It is required that aluminum sheet manufacturers have certain equipment investment and prodsuction and processing capabilities.
2. For the processing of the aluminum sheet, it is recommended that the aluminum sheet reinforcement be disconnected (disconnected) from the aluminum sheet fold and leave a gap:
1) The aluminum sheet is disordered thermal expansion and contraction on all sides, which belongs to surface deformation;
2) The thermal expansion and contraction of the stiffener in one direction along the long side belong to linear deformation;
3) Although the material is basically the same, the direction and nature of the deformation are different, resulting in different expansion and contraction. The difference in size between the two can easily affect the flatness of the board and the shedding of the implants;
4) Based on the above reasons, it is recommended to cancel the connection angle aluminum and rivets between the stiffener and the folded edge, and the length of the stiffener be 3-5mm less than the sheet gap.
3. The transportation process is also a link worthy of attention. The disorderly stacking of the sheets will aggravate the deformation of the aluminum sheet itself during transportation.
4. the keel system
At present, the common phenomenon in the market is the contradiction between effect and cost. The strict control of cost is the most important element that is indispensable for each project. Fifteen years ago, the keel system of aluminum curtain wall was aluminum alloy keel, and then the steel keel became the main support system. The deformation of steel columns and beams is large. Even with bolted and welded connections, the flatness of the skeleton system cannot be improved.
It is recommended to give priority to the aluminum alloy keel system when conditions permit.
Overview:
At present, whether it is uneven or the façade is easily polluted, the performance of the aluminum curtain wall has attracted great attention in the industry. A good building façade is the coat of a city. A good building cannot be separated from the enthusiastic investment of the builders in every link and marches in contradictions!