END USER INTERVIEW
DuPont ’ s solution for advanced sealing
DuPont ’ s Kalrez ® perfluoroelastomer components are central to addressing these challenges . Braule explains , “ Kalrez ® perfluoroelastomer parts are uniquely positioned to meet the demands of new clean energy applications and CO2 capture across various industries .” The distinguishing factor of Kalrez ® parts is DuPont ’ s control over the production process , from creating the base polymer to manufacturing the finished seal . This comprehensive approach allows for exceptional quality control , traceability and performance optimisation . Braule highlights the chemical structure that gives Kalrez ® parts its advantage : “ The carbon-fluorine bond provides excellent chemical and thermal resistance .” This robust chemical composition makes Kalrez ® parts particularly suitable for the demanding conditions found in H2 and CO2 applications , which can also include impurities
Comprehensive testing for assured performance
So that Kalrez ® seals perform reliably in these challenging applications , DuPont conducts thorough testing . Braule outlines their methodology : “ Our testing processes for H2 and CO2 environments are comparable to other gas or fluid tests for Oil and Gas services , with additional safety measures for hydrogen testing .” The testing parameters are extensive , covering , for example , pressure , temperature , gas concentration , exposure time and rapid gas decompression
Globe valve using Kalrez ® KVSP ( Kalrez ® valve stem packing )
Manual actuate pipeline valve where large Kalrez ® O-rings can be used on the flange groove .
resistance . Recent Rapid Gas Decompression ( RGD ) testing for hydrogen applications involved several steps :
• Using a specialised test fixture with multiple O-rings
• Compressing O-rings evenly while exposing them to gas
• Placing the test fixture in a pressure vessel
• Heating and pressurising the vessel
• Performing decompression cycles
The specific conditions for the study included pure H2 gas , 13 % seal compression , 200 bar pressure , 150 ° C temperature , a 72-hour hold time , and a 120 bar / min decompression rate .
Customised solutions for various applications
Recognising the diverse requirements across industries , DuPont offers several grades of Kalrez ® parts for different applications . Braule details some of these offerings :
• Kalrez ® Spectrum™ 6375 and 6380 for specific chemical environments
• Kalrez ® Spectrum™ 7075 and 7090 for extreme heat resistance above 300 ° C / 320 ° C in air .
• Kalrez ® OG193 and 0090 for superior Rapid Gas Decompression ( RGD ) resistance and gap extrusion resistance
• Kalrez ® Spectrum™ 7375 and 7390 for steam resistance and high heat resistance up to 300 ° C .
Additionally , Kalrez ® Valve Stem Packing ( KVSP™ ) is designed specifically to reduce unwanted emissions in control valve glands .
“ Kalrez ® Valve Stem Packing addresses the issue of fugitive emissions in petrochemical plants ,” Braule notes .
Practical applications and case studies
The effectiveness of Kalrez ® seals is best demonstrated through real-world applications . Braule shares two notable examples : 1 . Kalrez ® Valve Stem Packing ( KVSP™ ) in a petrochemical plant : Applied in control valve glands handling a mixture of pentane , butane , hexane , acetone and acidic water at -30 ° C and ~ 4.5 MPa , KVSP™ performed better than competitive PTFE packings . The outcome was an absence of detectable gland leaks and yearly savings of £ 54,000 per reactor unit . 2 . Kalrez ® 0090 O-Rings in sour gas application : Used in ball valves in the Oil & Gas industry , these O-rings managed sour feed gas with 5-15 % H2S and 2-5 % CO2 at temperatures from -7 to 121 ° C and pressures of 71 to 85 bar . Braule states , “ Due to their exceptional chemical resistance and outstanding RGD performance , Kalrez ® 0090 O-rings perform better than competitive FFKM seals and show minimal or no degradation .” The seals surpassed performance requirements of 24 months , compared to 6-12 months for competitive solutions , resulting in substantial cost savings and improved reliability .
The importance of collaboration in sealing technology
As the need for H2 and CO2-resistant seals grows , Braule emphasises the significance of collaboration . “ At DuPont , we maintain
16 Valve World December 2024 www . valve-world . net