Sealing solutions specialist Greene Tweed has supplied perfluoro elastomers (FFKM) to a leading petrochemical company.
The company’s goal was to increase the mean time between failure (MTBF) of its screw spindle pump from several weeks to several years.
The firm also wanted to increase safety at all of the pump installations in its ethylene oxide (EO) and propylene oxide (PO) plants. The rotary pump was used as a reactor pump carrying EO/PO media.
The faces of the pump’s mechanical seal has been statically sealed against the housing and the shaft by a variety of FFKM O-ring seals.
Previously installed perfluoro elastomers swelled and lacked sealing force. Since MTBF was only a few weeks, which was not acceptable for the customer, Green Tweed was contacted to provide a solution.
Based on Greene Tweed’s recommendation, the customer employed Chemraz 505 seals. This material is one of the few recommended for service in corrosive EO media.
Following the change to Chemraz 505, which reduced the risk of seal swell in EO/PO services, the O-rings have increased pump lifetime from several weeks to about four years.
The pump continues to run without problems with scheduled maintenance now set for every five years and it appears this goal will be met without a challenge.
POPULAR NEWS STORIES
LATEST VIDEOOseco Safety Cartridge - now CE marked and available in the EEA