By switching from gasket seals of PTFE to custom gaskets of DuPont™ Kalrez® perfluoroelastomer parts in the sensor head of a process instrument refractometer used by the food, pulp and paper and chemical industries, process instrument manufacturer K-Patents Oy, Vantaa, Finland, was able to dramatically extend instrument service life, increase reliability and safety, and reduce costs for the company and its customers.
Aggressive environment 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 attack by aggressive fluids. Because of inherent inelasticity, the original PTFE gaskets could not withstand the dynamic temperature fluctuations of many food, pulp and paper and chemical manufacturing processes, creating a leak path allowing process media to enter and damage the device. As a result, costly replacement of the PTFE seal became necessary approximately every 6–12 months.
Clean in Place Service Benefits from Kalrez® O-rings
Hilge-Pumpen AG, Swiss subsidiary of Philipp-Hilge GmbH, Bodenheim, Germany, selected Kalrez® 6221 perfluoroelastomer parts to seal its Euro-Hygia®, Hygiana-HT and Contra pump series, to meet the stringent safety, cleanliness and sterilization requirements demanded by the pharmaceutical, biotechnology and cosmetics industries.
Pumps used in pharmaceutical, biotechnological and sterile processes are subject to some of the highest standards and safety requirements worldwide. In addition to ease of operation they must also provide maximum biological safety without any unfavorable hydraulic characteristics that could adversely influence sensitive products.
Purity is critical to high wafer yield, and Kalrez® seals are designed with properties that help reduce contamination from particulates, outgassing and extractables.
Semiconductor Processing Seals
Kalrez® seals for semiconductor processing are field-proven in the manufacture of semiconductor chips.
They can help extend planned maintenance intervals, and thereby lower long-term cost of ownership, in a wide range of semiconductor processes. In a number of fabrication customer evaluations, Kalrez®seals exhibited improved mechanical strength, lower particle generation and longer seal life versus competitive perfluoroelastomers, in both static and dynamic sealing applications.
Kalrez® seals can help improve semiconductor manufacturing in a range of wafer-fabricating operations, including:
In valve jet printing, a series of inline jets are controlled by valves. These open and shut independently to produce streams of intermittent ink droplets. As the product passes the printhead, these droplets create characters and/or graphics based on grid information.
After each printing run, the printheads are washed by strong solvents or special chemicals to remove all inkjet materials from the printhead. With such aggressive media in the process, Kalrez® is an obvious material choice.
Keep reading to learn more about Kalrez sealing valves.
DuPont Performance Materials (DPM) is a leading innovator of thermoplastics, elastomers, renewable-sources polymers, high-performance parts and shapes, as well as resins that act as adhesives, sealants, and modifiers.
Gallagher Fluid Seals is a long-time partner of DuPont™, predominantly focusing on the Kalrez® line of products which is part of DPM. The latest perfluoroelastomer offering from DPM, Kalrez® Spectrum™ 7275, offers a higher level of sealing performance in the most aggressive chemical processing and manufacturing environments.
DuPont™ Kalrez® 1045 parts were phased out of the Kalrez product line at the end of March 2016. Kalrez 1045 parts have a long history of use in dinitrogen tetroxide (nitrogen tetroxide) service.
This chemical is often used as the oxidizer in rocket propellant, when combined with a hydrazine based rocket fuel. Nitrogen tetroxide is a very strong oxidizer, and Kalrez 1045 is resistant to oxidizing liquids; it has been the product of choice for hypergolic propellant applications.
Dramatic increases in instrument performance and reliability have been achieved where original PTFE gasket seals have been replaced with Kalrez® custom gaskets from the DuPont™ Performance Polymers range of products.
A Finnish manufacturer of process refractometers was utilizing process media at temperatures ranging from -20° to +220°C and pressures from 0.7 bar to 25 bar. These aggressive operating conditions resulted with the PTFE seals needing to be regularly replaced on a 6-12 months operating cycle.
However, after the seals were replaced by Kalrez® custom gaskets, there was no experience of fluid leakage over a 10 year period, even though the sealing products were subject to permanent in-line fluids immersion during this period.