Desuperheaters for Refinery Steam Systems

The SPAD is a small-pipe attemperator with a fixed-nozzle spray-ring design that clamps between two steam pipe flanges. The LPD is a large-pipe, probe-type desuperheater with a variable-nozzle, fully actuated control valve and 90-degree flanged insertion. B-Tech Valve identifies the LPD for steam pipes six inches and larger and the SPAD for smaller steam piping.

A spray-ring desuperheater introduces feedwater through fixed nozzles distributed around the steam passage. The water is supplied from a separate temperature control valve, allowing the system to regulate injection for the operating condition. Proper application requires review of steam conditions, water supply, pipe configuration, pressure class, and downstream requirements to support effective evaporation and temperature control.

The SPAD, Steam Attemperator, and LPD product information lists ASME B16.34 pressure classes 150, 300, 600, 900, 1500, 2500, and 2700. The correct selection should match the refinery steam system design conditions and piping requirements. B-Tech Valve can review the application and identify a suitable pressure-class configuration.

The listed SPAD, Steam Attemperator, and LPD products are temperature rated up to 1,200°F (650°C). Actual suitability depends on the complete application, including steam conditions, injection-water characteristics, materials, pressure class, installation arrangement, and required outlet temperature. Application details should be reviewed before selecting a configuration.

Installation varies by product. SPAD and Steam Attemperator designs clamp between steam pipe flanges, while the LPD uses a 90-degree flanged insertion into the steam pipe. Product selection should consider line size, available straight run, flange arrangement, control requirements, and access for inspection or maintenance.

Sizing typically requires the steam line size, steam pressure and temperature, required outlet temperature, steam flow range, injection-water conditions, pressure class, piping arrangement, and control requirements. B-Tech Valve offers application-sized products, so providing these operating details helps determine whether a fixed-nozzle spray ring or variable-nozzle probe-type design is appropriate.