Views: 2453 Author: Site Editor Publish Time: 2020-06-04 Origin: Site
rubber seals are widely used in various industries, so how do we judge the quality of similar rubber seals on the market? This article Hange will teach you how to judge the quality of similar rubber seals, and help you choose the most suitable seal for you.
Tensile properties are the first properties to be considered for rubber seals. They include: tensile strength, constant tensile stress, elongation at break and permanent deformation at break. Tensile strength is the maximum stress at which a material sample is stretched to break; The constant tensile stress is the stress reached when the elongation is specified;
The elongation is the deformation caused by the specified tensile force of the material sample (the ratio of the elongation increment to the original length), and the elongation at break is the elongation when the sample is broken; The permanent deformation after breaking is the residual deformation between the marking lines after the material is stretched and broken.
Hardness refers to the ability of rubber seals to resist external force and is one of the basic properties of seals. The hardness of rubber seals is also closely related to other properties. For example, the higher the hardness of the rubber seal, the greater the strength, the smaller the elongation, and the better the wear resistance. The low temperature resistance is often inversely proportional to the hardness.
Rubber seals are usually under compression. The rubber material has viscoelasticity, and the pressure will decrease with time under compression, which shows that the compression stress is relaxed; after removing the pressure, it cannot return to its original shape, which shows compression permanent deformation. This phenomenon is more obvious in high temperature and oil media, and this performance is directly related to the durability of the rubber sealing ability.
After rubber seals are subjected to oxygen, cold, heat, moisture, mechanical stress, etc., they will cause performance deterioration, which we call aging. The aging resistance can be expressed by the change of the strength, elongation and hardness of the rubber seal after aging. The smaller the change rate, the better the aging resistance.
5. Oil or medium resistance
In the application of vacuum systems, there are many media in contact with rubber seals, such as petroleum-based, diesters, silicate oil, and acid, alkali and other corrosive media in the chemical industry. Generally, at a certain temperature, the quality, volume, strength, elongation, hardness and other properties of the rubber seal are measured after being immersed in the medium for a certain period of time to assess the quality of the rubber seal's resistance to oil or medium.
By comparing the above five major aspects, we can basically get the performance advantages and disadvantages of similar rubber seals between different manufacturers. After a comprehensive comparison, we choose the best. Hange is worthy of your trust.