Metallized Carbon Corporation, a global leader in the manufacture of oil-free, self-lubricating, carbon-graphite materials for severe service lubrication applications, announces that its Metcar Grade M-58 has received approval from the FDA so that it can be used in food contact applications. This will permit the use of Metcar Grade M-58 in dry running, food mixer seals to provide lower seal friction and longer seal wear life. For pharmaceutical applications, there are several Metcar Grades that have passed the tests required for U.S. Pharmacopeia Class VI approved materials.
Dry running mechanical seals are used on large, vertical mixers to seal the clearance between the agitator shaft and the mixer housing at the location where the shaft enters the top of the mixer. Primary seal ring wear life has been a problem with these mechanical seals because they must run dry with high shaft run-out.