Duplex, Super Duplex, and Liquor Service Flanges

Bleach plant piping is the most aggressive service in the mill. Chlorine dioxide, hypochlorite, and the chloride content of process water combine to eat stainless grades that would last decades elsewhere. Duplex 2205 and super duplex 2507 are the practical answer, with the higher PREN of 2507 reserved for the worst stages.

The recovery cycle moves white liquor, green liquor, and black liquor through evaporators, recovery boilers, and the causticizing plant. Each stream has its own chemistry. Carbon steel works in some service, while duplex shows up where chlorides and temperatures climb together.

Brown stock washing, screening, and stock prep round out the mill. We supply duplex and super duplex weld necks and blinds in the sizes and classes that bleach plant and liquor service actually use, rather than the catalog standard.