FLUID COMPATIBILITY - TEST METHODS IN PREDICTING PERFORMANCE OF ELASTOMERIC MATERIALS USED FOR SEALING APPLICATIONS

摘要

When choosing the elastomer best suited for a specific application it is essential that the most important service conditions be considered first. Specific compounding of each elastomer is needed to design the most satisfactory material. Factors that should be considered in the selection of the optimum compound include chemical environment, service temperatures, operating pressures, and essential physical properties. In laboratory tests many elasto-meric materials show excellent chemical resistance to pure / blend reagents. However they may fail in actual service because of chemical attack by additives and / or impurities in the plant process stream. In some cases the chemical structure of the fluid is altered (e.g. because of high temperature) and the rubber compound, while resistant to the original chemical, might be attacked by the by-product. It is always a good practice to simulate laboratory test parameters as close as possible to actual working conditions, so that the chemical resistance can be verified. The purpose of this paper is to review the laboratory test methods utilized in verification of fluid - elastomer compatibility, such as stress - strain properties, volume and hardness change, etc. in predicting seal life performance.