How to control compression set to maintain sealing performance of silicone sealing gaskets under high temperature and long-term compression conditions?
Publish Time: 2026-04-27
In sealing engineering, silicone sealing gaskets are widely used in home appliances, automobiles, and industrial equipment due to their excellent temperature resistance and elasticity. However, under high temperature and long-term compression conditions, the material is prone to compression set, leading to a decrease in resilience, thus weakening the sealing effect and even causing leakage problems.1. Optimize material formulation to improve resilience performanceThe nature of compression set is closely related to the molecular structure of the material. By optimizing the silicone formulation, such as increasing the crosslinking density, selecting a base rubber with better high-temperature resistance, and adding appropriate reinforcing fillers, the elastic recovery ability of the material can be significantly enhanced. At the same time, introducing heat-resistant additives or modified components helps maintain the stability of the molecular chains in high-temperature environments and reduces performance degradation caused by thermal aging.2. Reasonably control the working compression ratioIn practical applications, the compression ratio of the gasket directly affects its deformation degree. While an excessively high compression ratio can improve the sealing effect in the short term, it will accelerate material fatigue and permanent deformation. Therefore, the compression range should be rationally designed according to the material properties, generally controlled between 20% and 30%, to achieve a balance between sealing performance and durability.3. Optimize Structural Design to Reduce Stress ConcentrationThe cross-sectional shape and stress distribution of the gasket have a significant impact on compression deformation. By adopting a reasonable cross-sectional structure, the stress can be more evenly distributed, avoiding localized stress concentration. Simultaneously, adding appropriate transition radii and reducing sharp edges in the design helps reduce localized material fatigue, thereby delaying the occurrence of permanent deformation.4. Control Operating Temperature and Environmental ConditionsAlthough silicone has a high temperature resistance range, it will still undergo aging reactions under long-term high-temperature conditions. Therefore, the operating environment should be avoided as much as possible, avoiding environments that exceed the material's long-term temperature resistance limit. Furthermore, aging will be further accelerated under the combined effects of high temperature, oxygen, and ozone; therefore, silicone materials with higher heat resistance or oxidation resistance can be selected when necessary.5. Improve Assembly and Pre-tightening DesignA reasonable assembly method can effectively reduce the long-term stress level of the gasket. For example, optimizing the preload design avoids excessive compression; employing an elastic compensation structure automatically compensates for minor material deformation during use, maintaining stable sealing pressure and mitigating the effects of compression set.6. Strengthen Process Control and Quality InspectionDuring production, the vulcanization process has a decisive impact on the performance of silicone. Insufficient or uneven vulcanization leads to instability in the internal structure of the material, thus exacerbating deformation. Therefore, vulcanization temperature and time should be strictly controlled, and product quality should be assessed through methods such as compression set testing to ensure it meets usage requirements.In conclusion, ensuring the stable performance of silicone sealing gaskets under high temperature and long-term compression conditions requires comprehensive optimization from multiple aspects, including material formulation, structural design, usage conditions, and manufacturing processes. Only through coordinated control of all aspects can compression set be effectively reduced, ensuring the long-term reliable operation of the sealing system.
