Small gap filling EMI beryllium copper strips refer to elastic substances that conduct electricity on the surface. Installing Small gap filling EMI beryllium copper strips at the junction of two pieces of metal can fill the gap, thereby eliminating the conductive discontinuity points. After using Small gap filling EMI beryllium copper strips, there are no larger holes in the gaps, thereby reducing the leakage of high-frequency electromagnetic waves. However, the usage method of Small gap filling EMI beryllium copper strips has a significant impact on the shielding effectiveness of the shielding body. The following points should be noted when using them:
In all kinds of Small gap filling EMI beryllium copper strips, finger-shaped spring pieces are allowed to slide in contact. Sliding contact is strictly prohibited for other kinds of spacers, otherwise it will cause damage to the spacers.
2. All types of gaskets will suffer irreversible damage when subjected to excessive compression. Therefore, a pressure-limiting structure should be set up during use to ensure a certain amount of compression.
3. Except for the conductive rubber gasket, when the electrical contact between the gasket and the shielding body is good, there is no positive relationship between the shielding effectiveness of the gasket and the compression amount. Increasing the compression amount does not improve the shielding effectiveness. The shielding effectiveness of conductive rubber increases with the increase of compression, which is related to the increase in the density of conductive particles in the conductive rubber.
4. The metal plates in contact with the gasket must have sufficient rigidity; otherwise, they will deform under the elastic force of the gasket, forming new discontinuous points and causing radio frequency leakage. For the front compression structure, an appropriate spacing of the fastening screws can prevent the panel from deforming.
5. When dimensions permit, thicker gaskets should be used as much as possible. This allows for greater processing errors in metal structural components, thereby reducing costs. In addition, thicker gaskets are generally softer and have lower rigidity requirements for the metal plate (thus avoiding radio frequency leakage caused by deformation due to insufficient rigidity of structural components).
6. The gasket material should be installed in a position that is not easily damaged. For instance, for large platform screen doors, the gaskets should be installed inside the door frame and provide certain protection. For detachable panels, it is best to install the gasket on the movable panel, so that when the panel is removed, it is convenient for storage.
7. The metal surface on which the gasket is installed must be clean and conductive to ensure reliable conductivity.
8. Try to use the groove installation method. The function of the groove is to fix the gasket and limit excessive compression. When using the slot installation method, the contact between the two parts of the shielding lift is not only achieved through the gasket but also through direct contact between metals. Therefore, it has the highest shielding efficiency.
9. There are two shapes of installation grooves: straight grooves and dovetail grooves. Straight grooves are easy to process, but the gaskets are prone to fall out. There is no such problem with the dovetail slot. The height of the groove is generally about 75% of the height of the gasket (for specific dimensions, refer to the compression amount required by the gasket manufacturer), and the width should ensure there is sufficient space to allow the gasket to stretch when compressed. When the gasket is installed in the straight groove, it needs to be fixed. Generally, the design data suggests using conductive adhesive for bonding, but this has two disadvantages: one is that it will increase the cost, and the other is that the conductive adhesive will age, resulting in a decline in shielding performance. Here, it is recommended to use non-conductive adhesive and apply a small drop to the area where the fastening screw passes through. In this way, although the adhesive area does not conduct electricity, the metal screw serves as a conductive contact ground, and the shielding effect is relatively stable.
10. The direction of sliding contact: Only finger-shaped reeds are allowed to slide in contact. When installing the reed, pay attention to its direction so that the compressive force applied by sliding can allow the reed to freely extend. Under normal circumstances, reed pieces can be bonded with back adhesive, but attention should be paid to the curing time (refer to the reed piece manufacturer's instructions). In harsher environments (such as excessively high or low temperatures, excessive mechanical force, etc.), a snap-on structure can be used.
11. Select appropriate gasket materials based on the base material of the shielding body to ensure that the contact surface reaches an electrochemical compatible state. For relevant designs, please refer to the materials provided later. If space permits, an environmental sealing gasket should be used simultaneously at the gap where the lining and gasket are installed, and the environmental sealing gasket should face the external environment to prevent the electrolyte from entering the contact surface between the conductive gasket and the shielding body.
12. The position of the screws: Generally, it is not very important for the screws to be installed on the inner or outer side of the sediment. However, in situations with high shielding requirements, the screws should be installed on the outer side of the liner to prevent the screws from penetrating the shielding box and causing additional leakage.
Small gap filling EMI beryllium copper strips https://www.emi-gasketech.com/Small-gap-filling-EMI-beryllium-copper-strips.html
Share this page with your family and friends.