Carbon Seal Rings used in railways in Diesel locomotives (engines)

It is also called expressor oil seal which forms a vital component of railway brake system.

Manufactured from specially formulated resin-impreganted carbon-graphite compound with superior physical properties, the carbon ring is machined to close dimensional tolerance and lapped to two light bands.

The expressor oil seal itself is manufactured from dimensionally controlled and mechanically tested components, to ensure better than 99.5 % performance.