Series A Class 600 Flanges

Series A Class 600 flanges are heavy-duty components for high-pressure, large-bore piping in the most demanding industrial environments. These flanges handle pressures up to the Class 600 envelope for pipe sizes from NPS 26 through NPS 60, making them essential for high-pressure gas gathering systems, FCCU regenerator lines, and main steam piping.

The weight of a Series A Class 600 flange at larger sizes is considerable. An NPS 48 Class 600 Series A flange can weigh several thousand pounds, requiring specialized rigging and handling procedures during installation. The bolt pattern uses large-diameter studs with heavy hex nuts, and hydraulic tensioning is the only practical method for achieving uniform bolt load.

Ring-type joint face configurations become increasingly common at Class 600 for large-diameter flanges, as the concentrated gasket loading of an RTJ groove provides superior sealing compared to a raised face at these pressures. BX-series ring gaskets are the standard choice for RTJ faces at Class 600 and above.