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Fisher® DMA, DMA/AF, DMA/AF-HTC, DSA, and DVI Desuperheaters

Fisher® DMA, DMA/AF, DMA/AF-HTC, DSA, and DVI Desuperheaters
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Fisher® DMA, DMA/AF, DMA/AF-HTC, DSA, and DVI Desuperheaters - 1

Product Bulletin Fisherr DMA, DMA-AF, DMA-AF-HTC, DSA, and DVI Desuperheaters Fisher DMA, DMA-AF, DMA-AF-HTC, DSA, and DVI desuperheaters can be used in many applications to efficiently reduce the temperature of superheated steam to the desired set point. Available variations are mechanically atomized (both fixed geometry and variable geometry) and steam assisted. Desuperheaters are available for installation in steam lines from DN25 through DN1500 (NPS 1 through 60) in diameter and are capable of maintaining steam temperatures to within 6_C (10_F) of saturation temperatures. W6298 Available Insertion Style Desuperheaters DMA–A simple mechanically atomized desuperheater with single or multiple, fixed-geometry spray nozzles is intended for applications with nearly constant load. The DMA is installed through a flanged connection on the side of a DN150 (NPS 6) or larger pipeline. Maximum unit Cv is 3.8. DMA-AF–A variable-geometry, mechanically atomized, back-pressure-activated desuperheater with one, two, or three spray nozzles is designed for applications requiring control over moderate load fluctuations. The DMA-AF desuperheater (figure 1) is installed through a flanged connection on the side of a DN200 (NPS 8) or larger pipeline. Maximum unit Cv is 15.0.

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Fisher® DMA, DMA/AF, DMA/AF-HTC, DSA, and DVI Desuperheaters - 2

Product Bulletin DMA-AF-HTC– The DMA-AF-HTC is functionally equivalent to the DMA-AF, however it is structurally suited for severe applications. The most common applications include boiler interstage attemperation, where the desuperheater is exposed to high thermal cycling and stress, high steam velocities and flow induced vibration. In addition to this specific application, the DMA-AF-HTC is suitable for other severe desuperheating application environments. The DMA-AF-HTC uses a construction optimized to move weld joints away from high stress regions. The desuperheater design incorporates...

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Fisher® DMA, DMA/AF, DMA/AF-HTC, DSA, and DVI Desuperheaters - 3

Product Bulletin Specifications Available Types J DMA, J DMA-AF, J DMA-AF-HTC, J DSA, and J DVI (see the Available Desuperheater Types section for descriptions) Connections See table 1 Maximum Pressure Rating(1) Consistent with applicable pressure-temperature ratings (as shown in table 1) per ASME B16.34 Inherent Rangeability Up to 50:1. The ratio of maximum to minimum controllable Cv is dependent upon the available water pressure differential Spray Water Pressure Required(2) 3.5 to 35 bar (50 to 500 psi) greater than steam line pressure Atomizing Steam (Design DSA) Atomizing steam should...

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Fisher® DMA, DMA/AF, DMA/AF-HTC, DSA, and DVI Desuperheaters - 4

Product Bulletin 85.2:DMA July 2014 temperature is controlled by varying the amount of spraywater flow. For the most efficient use of heat energy from steam, it is necessary to reduce the temperature of steam to near the saturation temperature. With steam that is at or near the saturation temperature, it is possible to recover the large amount of energy that was put into the steam when it was heated from water to steam. Desuperheating, or attemperation as it is sometimes called, is most often used to •improve thermal efficiency of heat transfer processes by using steam near saturation, •...

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Fisher® DMA, DMA/AF, DMA/AF-HTC, DSA, and DVI Desuperheaters - 5

Product Bulletin Figure 1. Fisher DMA-AF Desuperheater Figure 3. Fisher DMA-AF-HTC Desuperheater Figure 2. Fisher DSA Desuperheater Figure 4. Fisher DVI Desuperheater

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Fisher® DMA, DMA/AF, DMA/AF-HTC, DSA, and DVI Desuperheaters - 6

Product Bulletin Figure 5. Typical Installation FISHER 667-EZ SPRAYWATER CONTROL VALVE FISHER 667-EZ ATOMIZING STEAM ISOLATION VALVE SPRAYWATER ATOMIZING STEAM FISHER DSA DESUPERHEATER STEAMFLOW FISHER SPRAYWATER CONTROL VALVE FISHER DMA DESUPERHEATER STEAMFLOW DMA, DMA-AF, OR DMA-AF-HTC DESUPERHEATER

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Fisher® DMA, DMA/AF, DMA/AF-HTC, DSA, and DVI Desuperheaters - 7

Product Bulletin Figure 6. Selection Flow Chart YES REQUIRED TURNDOWN GREATER THAN 25:1 REQUIRED TURNDOWN GREATER THAN 20:1 PIPELINE SIZE GREATER THAN NPS 6 YES STEAM PRESSURE REDUCTION REQUIRED PIPELINE SIZE GREATER THAN NPS 6 PIPELINE SIZE GREATER THAN NPS 6 ATOMIZING STEAM AVAILABLE REQUIRED TURNDOWN GREATER THAN 5:1 Ordering Information 4. Atomizing steam pressure and temperature (DSA desuperheater only). Use the flow chart in figure 6 to select the appropriate desuperheater for your requirements. Dimensions are shown in figures 7, 8, 9, and 10. 5. Design conditions, if different from...

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Fisher® DMA, DMA/AF, DMA/AF-HTC, DSA, and DVI Desuperheaters - 8

Product Bulletin Table 2. Fisher DMA and DMA-AF Face-to-Face Dimensions Figure 7. Fisher DMA and DMA-AF Dimensions (also see table 2) ASME RF FLANGE (WATER) D (Nominal Pipe Size), NPS 1. DMA only. Note: For NPS 6 and 8 (DMA-AF only) mounting flange, add 69.6 mm (2.75 inches) to the A and T dimensions. For CL2500 mounting, consult your Emerson Process Management sales office. Refer to the certified drawing to verify the inside-diameter requirements of mounting for DMA-AF. Table 3. Fisher DMA-AF Minimum Mounting I.D. VALVE BODY PIPE MINIMUM BODY FLANGE WATER FLANGE NOZZLE MODEL DMA-AF-H...

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Fisher® DMA, DMA/AF, DMA/AF-HTC, DSA, and DVI Desuperheaters - 9

Product Bulletin Figure 8. Fisher DSA Dimensions (also see table 4) 254 (10.00) ASME RF FLANGE (STEAM) ASME RF FLANGE (WATER) 508 (20.00) Table 4. Fisher DSA Dimensions DIMENSION A mm D (Nominal Pipe Size), NPS Note: For NPS 6 mounting flange, add 69.6 mm (2.75 inches) to the A and T dimensions. For CL2500 mounting, consult your Emerson Process Management sales office.

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Fisher® DMA, DMA/AF, DMA/AF-HTC, DSA, and DVI Desuperheaters - 10

Product Bulletin Figure 9. Fisher DVI Dimensions (also see table 5) ASME RAISED-FACE FLANGE (WATER) ASME RAISED-FACE FLANGE 250 RMS SERRATED SURFACE FLOW DIRECTION INSTALLATION CONFIGURATION (2 GASKETS REQUIRED) Table 5. Fisher DVI Dimensions NOMINAL PIPE SIZE, NPS C–WATER CONNECTION TO MATING FLANGE A PRESSURE RATING

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Fisher® DMA, DMA/AF, DMA/AF-HTC, DSA, and DVI Desuperheaters - 11

Product Bulletin Figure 10. Fisher DMA-AF-HTC Dimensions (also see tables 6 and 7) MOUNTING FLANGE (SAME SIZE & PRESSURE RATING AS BODY FLANGE) E AVAILABLE NOZZLE CONFIGURATIONS GA32864-C Table 6. Fisher DMA-AF-HTC Dimensions DESUPERHEATER BODY FLANGE(1) Pressure Rating Pressure Rating WATER FLANGE Size, NPS 1. The NPS 4 DMA-AF-HTC requires a 4.00 inch minimum mounting I.D. Contact your Emerson Process Management sales office for NPS 3 DMA-AF-HTC minimum mounting I.D. Table 7. Fisher DMA-AF-HTC Installation Dimensions DIMENSION D (Nominal Pipe Size) Desuperheater Body Flange Size, NPS

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