Sealing technology manual for the process industry - Simriz®

75 Simriz® 494 (black) and 75 Simriz® 506 (white) Application profile For the prevalent requirements in the food and pharma- ceutical industries, Simriz® appears at first glance to be “over-engineered”. However, its cost effectiveness comes to the fore in the holistic view of maintenance and downtime costs which may occur, especially in safety-related appli- cations. Here, Simriz® provides reliability which pays off. Suitable areas of application • Water and water vapor • Concentrated acids (e.g. nitric acid 60%) • Amines (e.g. ethylenediamine) • Organic acids (e.g. acetic acid) • Ketones (e.g. methyl-ethyl-ketone) • Alkaline solutions (e.g. sodium-hydroxide, potassium- hydroxide) • Organic solvents (e.g. methanol) • Aroma concentrates Simriz® replaces elastomers such as EPDM or FKM when their temperature and media resistance can no longer cope with the demands of the application area, but rubber- elastic behavior is imperative. For example, hygienic design requirements in terms of absence of dead space and good cleanability only leave a minimal margin to the sealing element. Thermal expansion and media swelling must be as small as possible here. Under these stricter requirements with regard to purity and extreme media resistance, even in CIP/SIP processes and at temperatures above +150 °C (+302 °F), Simriz® delivers a high performance that is widely acknowledged in the market. Simriz® in the beverage industry Simriz® provides highly-reliable performance, especially for aroma-containing media, and thus safeguards the produc- tion process flawlessly. Simriz®in the chemical and pharmaceutical industries Simriz® can be used in almost all chemicals. Exceptions are the compounds of the alkali metals. Simriz® perfluoroelastomers (FFKM) are produced using special perfluorinated, completely hydrogen-free mon- omers, with appropriate compounding and processing techniques. They represent the high-end solution in ma- terials technology. Simriz® is characterized by a broad chemical resistance similar to that of PTFE, combined with the rubber-elastic properties of an elastomer. With Simriz®, Freudenberg of- fers a complete range of high-quality FFKM materials. In addition to the Simriz® compounds for standard and high temperature applications, there is a FDA- and USP Class VI-compliant variant, which is ideally suited for use in the food and pharmaceutical industries. General properties Thanks to FFKM, utmost temperature and media resistance is not reserved only to PTFE materials with a degree of fluor- ination of 76%. The operating conditions are limited when using PTFE due to its tendency to cold flow and lack of elas- ticity. At high pressures and many changes in temperature, pure PTFE seals prove to be unsuitable. Simriz®, on the other hand, combines almost the identical universal resistance of PTFE with the elastic advantages of elastomers. Therefore, with Simriz® many sealing problems can be solved better and easier. Simriz® also shows very reliable properties in static and dynamic applications, as well as in frequent temperature changes and aggressive media. In addition, Simriz® as FFKM offers the highest degree of fluorination among elastomers. The high bond ener- gy between carbon and fluorine atoms enables excellent resistance to a variety of chemicals with different reac- tive functional groups and the use in polar and non-polar media, even at high concentrations and temperatures. In addition, the temperature stability with approximately –10 °C to +325 °C (+14 °F to +617 °F) is extraordinarily compre- hensive for an elastomer. SIMRIZ® Elastomeric materials 42

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