1. Kalrez 4079 - General Purpose FFKM

    Recognized as the leading supplier of perfluoroelastomer parts for over 40 years, DuPont offers a variety of high performing products that are formulated to give the best possible seal performance in numerous aggressive environments. Excellent balance of finished properties is achieved through careful use of proprietary polymers, cure systems, fillers and additives, resulting in superior seals for a broad range of applications.


    Kalrez® 4079

    Kalrez® 4079 is among the most popular of all Kalrez compounds. Released in the 1980's, this compound has been a mainstay and go-to for many Gallagher customers. 

    Kalrez® 4079 parts are a low compression set product for general purpose use in O-rings, diaphragms, seals and other parts used in the chemical process and aircraft industries.

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  2. Kalrez® Composite Seals for Standard and Complex Geometries

    For over 40 years, DuPont™ has been relentless in pursuing improvement in the manufacture of perfluoroelastomer (FFKM) parts. Elastomeric parts typically consist of three components: a polymer chain (the backbone of the elastomer), a crosslinking system (which links the polymer chains together and is the key to elasticity and sealing performance), and a filler system (used to enhance mechanical properties). Based on extensive experience, DuPont™ adjusts these components to optimize seal performance.

    Composite Seals for Standard and Complex Geometries

    For demanding standard and complex composite seal applications, Kalrez perfluoroelastomer parts are the elastomer of choice designed and molded to your specific requirements.  Kalrez composite seals offer unique one of a kind parts, in a wide variety of custom family shapes, standard geometry, and miscellaneous bonded parts, including small and large parts.  Whether you have a niche application or high volume runs, your sealing requirements can be met.  Kalrez composite seals are available in a variety of compounds depending on the thermal, chemical and plasma resistance required.


    Kalrez® composite seal applications include; micro valves, micro-pumps, downhole oil and gas, semiconductor chip process equipment, ink jet, beverage dispensers, car wash pumps, printers, paint spray, refineries, CPI and more.

    Types of Kalrez Shapes/Geometries

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  3. Kalrez® O-rings for Hydrogen Sulfide Removal

    Kalrez Perfluoroelastomer Seals: Authorized DistributorAmine treatment is a process typically used for Hydrogen Sulfide removal from natural gas (sour gas). This operation is commonly referred to as gas “sweetening," acid gas removal, or amine scrubbing

    Amine units are used all over the world in oil refineries and gas plants to remove hydrogen sulfide (H2S) from a product stream. New environmental standards are more strict and require ever-decreasing contents of H2S in clean natural gas. Most of the new sources of oil and gas discovered today have high contents of H2S which demand more efficient removal technologies (the Shah Gas

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  4. Kalrez® Spectrum™ 7275 Doubles Seal Life

    Kalrez Spectrum 7275 is a perfluoroelastomer that provides long life sealing in an array of aggressive chemical environments that typically make sealing difficult: ethylene oxide, acrylic monomers, silanes and chlorosilanes, and strong oxidizers such as nitric acid, chlorine and chlorine dioxide.

    It has demonstrated improved chemical and compression set resistance and mechanical property retention when compared to competitor’s elastomers.

    Kalrez Spectrum 7275 is based on a proprietary cross-linking system, and is uniquely identified by its light brown shade.

    Targeted applications include industries that depend on mechanical seals, pumps, valves, compressors, filtration columns and analytical equipment for their critical processes.

    Success Story: Kalrez® Spectrum™ 7275 Double Seal Life in Chlorine Dioxide Service


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  5. Kalrez PV8070 Parts in Reactors

    High Performance Seals for Polycrystalline Silicon Process Equipment

    The Challenge

    To meet growing demand in solar cells, the Siemens* process is used to produce highly purified polycrystalline silicon by thermally decomposing tri-chloro-silane (TCS). The reactors employed require three kinds of high-performance seals in the following locations: A) bell jar seals; B) electrode seals between the electrode and ceramic inlet; and C) a gasket for the view port seal (see schematic).

    pv8070 seals in Polycrystalline Silicon Process Equipment

    Application Details

    The process involves a very hot, dry environment with temperatures up to 1200°C (2100°F). Sealing components see up to 300°C (572°F). Process media include TCS and aggressive by-products of its decomposition, such as HCl gas. Superior compression set performance is needed for effective sealing and extended seal life. Very low outgassing is a key requirement for preventing contamination of the process environment.

    The presence of harsh chemicals in high temperature conditions often require an upgrade from standard sealing materials to PTFE or fluoroelastomers (FKM) to improve thermal stability and chemical resistance. However, PTFE can deform and creep “hot flow” in the bell jar seal increasing the risk of product loss. FKM, with its high temperature rating of 200°C (392°F), also has deficiencies in this 300°C (572°F) environment.

    The Solution and Key Advantages of Kalrez PV8070

    Kalrez PV8070 perfluoroelastomer parts installed as washers and gaskets in reactors for the Siemens CVD process have demonstrated outstanding performance in this demanding application. Kalrez® PV8070 parts are effective seals that provide:

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  6. Kalrez® 1050LF General Purpose FFKM

    kalrez 1050LFDuPont™ Kalrez® 1050LF perfluoroelastomer parts are a carbon black-filled general-purpose product for o-rings, seals, and other parts used in chemical process industries. It is a classic-grade and longtime favorite for premium performance and provides a more economical option than similar compounds such as 7375.

    Kalrez 1050LF o-rings can maintain their recovery with elasticity following high-pressure applications, maintaining a tighter seal for longer periods of time compared to other compounds. With a pressure rating of 1,500 PSI, it can help extend seal life and integrity, ultimately lowering costs.

    With above-average hot water

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  7. What Makes Kalrez® Different?

    Oil and gas production and chemical manufacturing industries present sealing technologies with some of the harshest and most demanding operating environments.

    Harsh and Demanding Operating Environments Require Chemically Resistant and Thermally Stable Seals

    "We screen Kalrez against some of the most aggressive corrosive fluids," says Dr Christopher Bish, Technical Fellow. "And in addition to the fluid testing, we did some compression set testing and stress relaxation testing at high temperatures. We now have one of the most chemically resistant and thermally stable compounds possible."

    We screen Kalrez against some of the most aggressive corrosive fluids

    What really makes Kalrez sealing technology superior and more durable than competitors?

    One of the things that sets Dupont Kalrez apart is their quality control system, which gives them the ability to track materials as they flow through the plant. Scanning the barcode on

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  8. Kalrez® 7375 Offers Outstanding Properties & Performance

    Kalrez 7375 offers broad chemical and water/steam resistance

    The newer compound from DuPont™, Kalrez 7375, is an innovative FFKM oil-seal product exhibiting broad chemical and water/steam resistance properties required at high temperatures in chemical process industry applications. Kalrez 7375 parts present excellent compression set resistance, exceptional physical property retention, and improved mechanical strength properties. Other Kalrez compounds have done the job over the years when faced with many of these sealing challenges, but how does it compare to this new compound?

    Three ways that Kalrez 7375 would be a suitable upgrade or compatible compound for your application:

    1. Kalrez® 1050LF is a classic grade and longtime favorite for premium performance. 1050LF end-users will likely see a performance boost if they switched to 7375, especially

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  9. Semiconductor Fabs Lower Cost of Ownership with HiFluor Materials

    Article re-posted with permission from Parker Hannifin Sealing & Shielding Team.

    Original content can be found on Parker’s Website and was written by Nathaniel Reis, Applications Engineer for Parker O-Ring & Engineered Seals Division.

    parker hifluor processIn our semiconductor entry from last month, we noted that lowering the cost of ownership is a multi-faceted goal. We discussed how one of the areas for potential

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  10. How to Choose the Best Sealing Materials Based on Chemistry & Strong Oxidizers

    Strong oxidizers can damage metal, causing pitting or rust and treating possible safety concerns.

    In chemistry, strong oxidizers are substances (like chromic acid) that can cause other substances (like seals and gaskets) to lose electrons. So, an oxidizer is a chemical species that undergoes a reaction that removes one or more electrons from another atom.

    This causes a change in mass. Metals will turn into their respective heavier oxides, and the carbon in graphite will oxidize into carbon dioxide—which, although molecularly heavier, is a gas at room temperature.

    This happens in pumps, valves, pipelines or any other equipment that have seals and gaskets carrying a strong oxidizer. It will cause pitting or rust and, depending on your choice of seal material, may require shorter service intervals. Ultimately, you may have to look for a more suitable material that can handle strong oxidizers.

    More importantly, an oxidizing agent can cause or contribute

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