Metallized Carbon Corporation, a manufacturer 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.
Metcar grade M-58 is an electro graphite base material that contains a special additive to reduce friction and improve the dry running wear rate. Available fully machined to the customer’s drawing specifications, Metcar Grade M-58 primary seal rings can be used in temperatures between -30 and 800 F.
It is anticipated that Metcar Grade M-58 will also be useful in many other machine part applications where an FDA approved, self-lubricating material, with low friction and long wear life is required. For FDA approved bearings, seal rings, vanes, rotors, end plates, piston rings, valve seats and other machine parts that must run submerged in beverages or liquefied foods, Metcar carbon-graphite grades that are impregnated with thermal setting resin, copper, tin bronze or nickel chrome are used.