dupont
- 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.
Each time the mechanical maintenance team performed a clean-in-place procedure at 80 °C, or made a product change on the filler, the PTFE seals became mechanically damaged. This meant they had to change the PTFE O-rings on a daily basis, since seal lifetime never extended beyond 24 hours before replacement.
In a different application at the same plant, seals of FEP/FKM, fitted to the piston rod of a Type SRC Alfa Laval valve, failed regularly after only
- 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 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 field in the United Arab Emirates for example has up to 30% H2S).
The Challenge of Amine Units in Harsh Chemical Environments
Amine units operate under harsh chemical environments. H
- 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:
- January 15, 2020
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 the
- October 11, 2018
The Challenge
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.
The Solution
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. - September 05, 2017
Purity is critical to high wafer yield, and Kalrez® seals are designed with properties that help reduce contamination from particulates, outgassing and extractables.
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.
Operational Improvements
Kalrez® seals can help improve semiconductor manufacturing in a range of wafer-fabricating operations, including:
- Deposition
- Etch
- Ash/strip
- Thermal
- Wet
- September 22, 2016
Gallagher Fluid Seals is a proud of its longtime partnership with DuPont®, having specified thousands of perfluoroelastomer parts over the past few decades.
DuPont is at the forefront of perfluoroelastomer development, creating elastomers with properties that can help meet highly specific application requirements.
But how do you know which elastomer is right for your application? DuPont provides this helpful guide.