Emerson Process Management has introduced the 1″, 1-1/2″ & 4″ trim sizes of their Fisher NotchFlo DST control valve trim that prevents the cavitation and clearance-flow problems typical to high-pressure liquid applications within the power generation industry, in oilfield production use, and in refinery recirculation and letdown services. These sizes have been added to the existing 2″ & 3″ sizes, and completing the trim offering. The NotchFlo DST control valve trim features a longitudinal flow path that incorporates a series of pressure staging notches. The notches achieve the required pressure drop while avoiding conditions that would cause cavitation and result in trim damage. The pressure staging design and separation of shutoff and throttling locations prevent high pressure drops from occurring at the trim seat when at low flow conditions. This avoids clearance flow erosion of the seat line, thereby extending the already long-term shutoff capability of the valve trim. As an added benefit, the relatively large flow passageway through the design allows control of liquids with entrained solids. Flow rangeability is 50:1. The NotchFlo DST control valve trim is pressure-balanced, which yields smoother operation and reduces actuator size requirements. The valve plug features a large-diameter stem for added rigidity against high-pressure conditions. NACE materials are available for corrosive applications. NotchFlo trim and Fisher valves work with FIELDVUE(R) controllers to comprise the intelligent, digital field devices that power the PlantWeb(R) digital plant architecture to deliver asset management, process automation, and management execution. Further cost savings, increased plant availability, and enhanced safety and environmental compliance are achieved when the Fisher digital valves are integrated into the PlantWeb architecture.
