Screw installation method
(1) the screw pitch can be properly configured according to the thickness of the plate. The spacing is too small and too large. If the spacing is too small, sometimes it will cause stress due to too tight and cause damage. If the spacing is too large, it will make the PC board unstable. To this end, the following spacing is recommended.
A: the thickness of the plate is less than 3.0mm, and the distance is 10~20cm
B: the thickness of the plate is more than 3.0mm, and the distance is 20~30cm
C: if the bar is fixed, the distance is 20~30cm
Note: if the PC plate is fixed directly with self tapping screws, the larger the screw pitch, the less likely the plate will be damaged due to stress.
(2) the size of the screw hole should be taken into account in the PC summer and winter seasons. Generally speaking, the diameter of the screw should be 2~4mm larger than the diameter of the screw, so as to reserve the expansion space.
(3) when the position of the screw hole is too close to the edge of the PC plate, it is very easy to cause a broken plate. Generally, the position of the screw hole is more than 2.5 times the diameter of the screw hole on the edge of the PC plate. For example, the diameter of 4mm screws, the location of screw holes should be at least more than 1cm from the edge of PC plate.
(4) do not lock the screws too tightly, otherwise they will cause deformation and stress.
(5) the screws that are locked on the PC board should not choose self tapping screws. Otherwise, the stress will be generated and the stress will increase with the thickness of the sheet.
(6) in order to reduce the direct pressure of the screw, the washer can be used to fill it, but the PVC washer and some rubber rings will damage the PC plate and not be used. The material of the washer is recommended to be three yuan ethylene propylene rubber, silicone rubber and neoprene.
Dry assembly method
The so-called dry type, that is, do not use sealant. Because sometimes the expansion of the plate exceeds the extension of the sealant.
The advantage of the dry assembly system is that the sealant strip is pressed tightly inside the bar (aluminum alloy section) to allow the plate to move freely when it is expanded and moved by the load position.
No PVC sealant strip shall be used, because the plasticizer added to soft PVC will migrate to the surface of the sheet, which will cause cracking on the surface of the sheet and even damage to the entire panel. The suitable sealing materials are chloroprene rubber or EPDM, and their hardness is about Shao's A65.
Wet assembly method
This assembly system is mainly used for small facilities, such as steam garage, station canopy, eaves, greenhouse and many other occasions that replace glass. When the wet assembly method is used, as shown in Figure 2, the basic requirement is that the seal system will be able to withstand a certain amount of movement of the plate, allowing thermal expansion without reducing the bond force between the frame and the plate. It is generally recommended to use the wet assembly of neutral silicone rubber and hollow sun plate, but special attention should be paid to the chemical properties of the sealant used before use. The acid and alkaline silicone rubber must not be selected, because these curing agents will lead to the crack of the plate, especially when the sealant is selected, except when the sealant is selected. Besides adaptability, we should also focus on testing, extension and weatherability.
A sturdy condition
Whether dry assembly or wet assembly, no matter horizontal, vertical and inclined installation. In the installation of hollow sunlight panels, the most important thing is the fastening of the edges.
(1) there must be room for expansion and load displacement in the connection section or in the slot of the frame. The linear thermal expansion coefficient of the hollow sun plate is 7 x 10m/m.k, that is, the temperature increases at 1 degrees centigrade, and the 1m x 1m plate expands in the direction of the length of 0.075mm. The user must calculate the installation gap according to the temperature difference of the four seasons according to the site of the project. For example, the maximum temperature of the north area is 40, the lowest temperature is -30, 1m x 1m. The gap is 0.07 x 70=4.9mm
(2) at least one arbor should be included in the gripped part of the sheet, or the minimum part 20mm should be engaged at the edge of the plate.
Generally speaking, the total depth of slots made of profiles should include the meshing of 20mm and the clearance due to thermal expansion and deformation due to load.