kalrez
- April 07, 2026
Kalrez® Spectrum™ 7275 Double 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
- December 23, 2025
Kalrez® Bonded Door Seals
Bonded door seals for gate valves and slit valve door seal applications provide improved sealing performance versus conventional O-rings by reducing particle generation, extending seal life, and minimizing replacement time during preventive maintenance.
DuPont™ Kalrez® bonded door seals are designed for easy installation and low particle generation. They combine a custom seal design and proprietary
- February 14, 2025
Kalrez® Parts Extend Service Life for Process Instrument
Aggressive environment was challenging for PTFE
Through permanent in-line fluids immersion, K-Patents’ “PR-01-S” refractometer is exposed to temperatures from –20 ° to +220 °C, pressures from –0,7 to +25 bar, and some 500 process fluids and chemicals, many of which are extremely aggressive. Delicate digital detector circuits and fiber optics in the sensor head are sealed by two gaskets from
- March 09, 2023
The PTFE Seal Challenge
The filling line at Dow AgroSciences plant in Drusenheim, France - a global leader in pest management and biotechnology products - processes aggressive solvents, surfactants and concentrated herbicides at temperatures ranging from 10 to 45 °C, and pressures from 1.5 to 3.5 bars Eff. Filling machine valves on the line were fitted with dynamic PTFE O-rings, while the machine hoses were equipped with static O-rings, also of PTFE
- February 23, 2023
Kalrez® 0040 and Kalrez® 0090
What are the similarities and differences between these two special purpose low temperature FFKM compounds?
It's known that DuPont™ Kalrez 0040 and Kalrez 0090 are two of the most popular low temperature
- August 03, 2022
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,
- April 19, 2022
DuPont™ Kalrez® 8575 perfluoroelastomer parts are a white product for “select” etching, ashing/stripping and deposition process applications. It offers low weight loss in Oxygen and Fluorine-Based Plasmas, low outgassing and excellent elastic recovery properties. Kalrez® 8575 has excellent vacuum and long-term sealing performance, good mechanical properties and is well-suited for both static and dynamic sealing applications (e.g., gas inlets, chamber lid seals, slit valve door seals, etc.). A maximum
- March 09, 2021
Kalrez® FFKM Seals Help Minimize Wafer Process Contamination
- September 17, 2020
Amine 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
- May 08, 2020
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).
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:

