Material Requirements For The Selection Of Seal Products:
Apr 20, 2022
Due to the differences in the properties of the materials used to produce the seal products, the sealing performance of the produced seal products will also be very different. Therefore, understanding the material properties of the production seals is a necessary prerequisite for the correct design and selection of seal products. In the production of seals, the selection of materials should consider the following points:
1. The medium resistance of the material
The degree of swelling of the material of the seal product in the medium is directly related to the sealing performance of the sealing system. Therefore, when selecting materials for the production of hydraulic and pneumatic seals, the first thing to consider is whether the material properties of the seal product can be compatible with the sealing medium.
2. The tensile strength of the material
The tensile strength of the seal material usually decreases with the increase of the working temperature, so the mechanical strength of the seal product under high operating temperature and high temperature working environment must be considered. The low tensile strength will easily lead to sealing. The pressure of the product is loose and deformed, which is suitable for the failure of the sealing performance.
3. Material wear resistance
The wear resistance of the seal material is a required property of the dynamic seal product. The better the wear resistance, the longer the service life of the seal in the working environment. The wear resistance of the seal material is closely related to the hardness of the material. The higher the hardness of the material, the better the wear resistance will be.
4. Deformation of materials
The hydropneumatic seal obtains the sealing ability by generating recoverable compression deformation in the sealing groove. Therefore, the deformation of the seal material should be small, the elasticity should be high, and the resilience should be strong. In addition, material deformation is related to the temperature of the working environment, and low or high temperature will increase the possibility of deformation.
5. The elasticity of the material
Extrusion seals rely on the resilience performance of the seal product itself to obtain the sealing effect, while the lip seal product may have eccentricity, and the elasticity of the material should be used to compensate for the insufficient contact pressure of the seal. Therefore,elasticity is essential to the sealing effect of the seal.
6. The hardness of the material
Hardness is a very important indicator of seal material, which needs to be determined according to the smoothness of the sealing surface. If the sealing surface is rough, the hardness of the sealing product should be lower, so that the sealing effect will be better. In a working environment with high sealing pressure, the hardness of the seal is required to be relatively increased to prevent the seal from being excessively deformed or even extruded under high pressure. In addition, the hardness of the material decreases as the temperature of the working environment increases, and the higher the hardness of the seal, the better the wear resistance of the material.
7. Temperature resistance
The working environment temperature of the seal product depends on the temperature of the sealing medium and the temperature rise of the seal itself during the movement. Temperature will directly affect the sealing performance of the entire hydraulic system. If the temperature is too high, the aging of the sealing material will be accelerated, resulting in a significant reduction in the elasticity and hardness of the material. Too low temperature will also cause the material to harden, lose its due elasticity, and reduce the sealing effect. Therefore, the selected seal material should have a relatively large temperature range.
