A wide range of desuperheaters, pneumatic actuators, strainers to satisfy all specifications of the power, pulp and paper industry and process gas applications FEATURES Fabricated construction Special design for small steam lines with minimal steam pressure losses Steam control within 6 C of saturation temperature and ± 1% of controller range Venturi type vena contracta Wide range of C v (K v ) capacities Pressure class and connections: - ASME B16.34 class 150 to 600 - EN 1092-1 class PN 16 to PN 100 - butt weld connections to ASME B16.25 or EN-ISO 9692 Materials - ASTM SA 182 F11 / SA 335 P11 - or EN 1.7335 - other materials upon request GENERAL APPLICATION Turbine gland sealing Air ejectors Nox steam for gas turbines House steam Drum dryers Tire molds Vulcanizing equipment and cooking kettles TECHNICAL DATA Sizes: Steam NPS 1½ - 4 (DN 40-100) Water NPS ½ - 1 (DN 15-25) www.valves.emerson.com 2017 Emerson. All Rights Reserved. VCTDS-03066-US 16/12
Water inlet Water pipe nipple is available to various standards. Construction in accordance to ANSI, DIN, JIS and BS Water inlet flange is available to various standards ANSI NPS ½ - 1 DIN DN 15-25 Body is available in various materials. Construction in accordance to ANSI, DIN, JIS and BS Steam connection, in a wafer design, raised face or butt weld: ANSI NPS 1½ - 4 DIN DN 40-100 Water channel in body bore Diverging venturi contour Converging venturi contour Water spray port elliptical shape Steam flow Water swirl chamber Steam venturi insert Water tangential slot FIGURE 1 2
The Small Pipe Inline Desuperheater (SPID) has been specifically designed to provide precise steam temperature control in small steam lines. In process applications where control of the product temperature is critical to the final quality, it is essential that fine steam temperature control is maintained. The pressure reduction of saturated steam in throttling valves often results in a lower pressure superheated steam. This superheated steam has a lower heat transfer capability than the saturated state resulting in decreased production. High superheat temperatures can also damage the product or heat exchanger components. The SPID Desuperheater offers a reliable economical solution for steam temperature control in process and utility applications. This is achieved by creating atomized water droplets sprays and injecting them into small steam lines with minimal steam pressure losses. These atomized water droplets have high surface to volume ratios encouraging rapid heat transfer. Rapid vaporization occurs for efficient cooling of the superheated steam without the need for pipe liners. CODES AND STANDARDS The SPID Desuperheater is designed and manufactured to meet a wide variety of international codes and standards. Certified acceptance documents are available upon request. If special codes or standards are required by your local authority, then we would be pleased to discuss them. SYSTEM COMPARISON Conventional Conventional injection water systems consist of: Fixed size spray nozzle Control valve Steam pipe section The steam passes through a vena contracta. The upstream side is a high recovery (low loss) converging contour where velocity and resulting turbulence increase. The downstream side is a rapidly diverging contour causing separation of the steam flow from the boundary surface. This separation provides space for the emerging water spray pattern to fully develop and mix with the steam thereby avoiding thermal shock to downstream piping. Cooling water is monitored into the SPID by a temperature control valve (TCV). The TCV responds to the output signal of a temperature indicating controller (TIC) connected to the downstream temperature sensor/transmitter (TT). Modulation of the TCV varies the amount of water entering the SPID (see figure 2). Cooling water entering through the SPID s water flange connection travels to the water channel which runs circumferentially around the body bore. Multiple water slots in the outer surface of the nozzle insert will tangentially deliver the water into the swirl chamber. The swirl chamber s conical shape forms a converging section that accelerates the rotating water. It then passes through a constant bore for stabilization. The rotating high velocity water exits through what is an elliptical shape in the surface of the diverging side of the steam nozzle. This shape effectively causes the spray to discharge in an axial direction with the steam flow. The resulting finally atomized hollow cone water spray emerges and fully develops before mixing with the steam. FIGURE 2 Water TCV Desuperheated steam Desuperheated steam 3
APPLICATIONS The SPID Desuperheater is used upstream of process steam shell and tube heat exchangers. Often process steam equipment experiences chronic tube fouling due to product break out from high superheat temperatures resulting in decreased heat exchanger efficiencies and costly lost production during down time clean outs. Here the final product can benefit from controlling process steam temperatures to within 6 C of saturation and within ± 1% of controller range. Powerhouse applications would include steam turbine gland sealing, air ejectors, Nox steam for gas turbines and house steam needs. Other applications include steam for drum dryers, tire molds, vulcanizing equipment and cooking kettles. In general, any steam desuperheating in small pipe lines. WATER SPRAY PORTS The SPID Desuperheater may be equipped with a variety of water spray ports. The uniform steam nozzle insert accepts spray ports with a wide range of C v (K v ) values. Standard configurations are with either 1 to 8 equally sized spray ports are available with a rangeability of 1 : 40 depending on application. This feature enables the SPID Desuperheater to be customized to specific system requirements. Consult Yarway or your local representatives for details. TABLE 1 - SPID STANDARD CAPACITY RANGE Body Size Ports 1 2 3 4 5 6 7 8 B NPS 1½ C v = 0.015 0.030 0.045 0.060 0.075 0.090 - - DN 40 K v = 0.013 0.026 0.039 0.052 0.065 0.078 - - C NPS 2 C v = 0.030 0.060 0.090 0.120 0.150 0.180 - - DN 50 K v = 0.026 0.052 0.078 0.104 0.130 0.156 - - D NPS 3 C v = 0.050 0.100 0.150 0.200 0.250 0.300 0.350 0.400 DN 80 K v = 0.043 0.086 0.129 0.172 0.215 0.258 0.302 0.345 E NPS 4 C v = 0.100 0.200 0.300 0.400 0.500 0.600 0.700 0.800 DN 100 K v = 0.086 0.172 0.258 0.344 0.430 0.516 0.602 0.688 H W G W FIGURE 3 H 1 G ST H 2 G ST + G W SIZING FORMULA Every desuperheating station is a mixing point where there is a heat and mass balance. The universal formula is: G W = G ST ( H 1 -H 2 ) : ( H 2 -H W ) In which: G W = G ST = H 1 = H 2 = H W = Injection water mass Inlet steam mass Enthalpy of the inlet steam Enthalpy of the outlet steam Enthalpy of the injection water This formula enables calculation of the quantity of water required to lower the inlet steam temperature to the set - point temperature of the outlet steam. 4
IMPORTANT SYSTEM PARAMETERS Apart from the spray quality of the atomizer (primary atomization) there are other system parameters which influence the desuperheater stations performance. These are: Water to steam ratio This ratio is determined by dividing G W by G ST = 6 : 1. Above this ratio, proper evaporation of the injection water cannot always be guaranteed. In case of doubt, consult Yarway. Distance to sensor The distance from the SPID Desuperheater to the temperature sensor should be 12 to 15 meters, although the distance specific to the application is advised by Yarway at the enquiry stage. Longer distances will ensure that full evaporation of the water will take place at lower velocities. Required straight pipe run The minimum pipe run, required downstream, varies with each individual application and is specified by Yarway at the enquiry stage. This straight run is needed to prevent erosion due to impingement of water droplets against pipe walls, valves and fittings. Upstream straight run is normally 2 x D and the downstream straight run 20 x D, as a minimum. ORDERING/SIZING DATA Steam desuperheaters are selected specifically against application data. For optimal sizing, the following comprehensive data should always be supplied. Steam data Inlet pressure bar Inlet temperature C Outlet temperature C set point Steam flow max. t / hr Steam flow normal t / hr Steam flow min. t / hr Water data Water pressure bar Water temperature C General Pipe size Pipe schedule mm Application Yarway does recommend a strainer with a mesh size of approx. 100 µ in the water supply line to protect the SPID Desuperheater from clogging. For applications outside these limitations, consult Yarway or your local representative. TABLE 2 - MODEL NUMBER SPECIFICATION Sample model number 8 A 600 W080 C 4 600 F 8 Designation for the SPID which is the Series 80000 A ANSI - American National Standards Institute D DIN - German Industrial Standards J JIS - Japanese Industrial Standards B BS - British Standard Body rating selections F raised face flanged wafer ends. If flanged, then = F 000 W butt weld ends If butt weld, then: ANSI: incl. schedule 80 = W080 DIN - JIS - BS: incl. schedule thickness 6.02 = W602 Body size letter selections Available C v (K v ) selections Water flange rating selections should be equal to or greater than the body rating F Raised face flange water connection 5
TABLE 3 - STANDARD MATERIALS Item Name Material 4 4 1 Body ASTM SA 182 F11 2 Insert AISI 431 3 Nipple ASTM SA 335 P11 4 Flange ASTM SA 182 F11 CERTIFICATION 3 3 B SPID Desuperheaters are approved by authorized authorities to comply with the requirements of ASME B16.34. All data subject to changes. NOTE Dimensions may be subject to change without prior notification. Yarway will provide a certified dimensional drawing upon request. 2 2 1 1 A RF A BW FIGURE 4 TABLE 4 - DIMENSIONS - WEIGHT Weight A B Water connections Size kg lbs Body Steam connections mm inch mm inch Size Rating 1½ 2.7 6.0 ASME class RF (wafer) 40 1 9 /16 200 7⅞ ½ ASME class 150/300/600 150/300/600 BW sched. 40 60 2⅜ 206 8 3 /32 flanged BW sched. 80 60 2⅜ 211 8 5 /16 RF 2 3.7 8.2 ASME class RF (wafer) 40 1 9 /16 225 8⅞ ½ ASME class 150/300/600 150/300/600 BW sched. 40 65 2 9 /16 231 9 3 /32 flanged BW sched. 80 65 2 9 /16 236 9 5 /16 RF 3 6.9 15.2 ASME class RF (wafer) 50 1 31 /32 240 9 7 /16 ½ ASME class 150/300/600 150/300/600 BW sched. 40 75 2 31 /32 246 9 11 /16 flanged BW sched. 80 75 2 31 /32 251 9⅞ RF 4 11.8 26.0 ASME class RF (wafer) 60 2⅜ 255 10 1 /32 1 ASME class 150/300/600 150/300/600 BW sched. 40 85 2 11 /32 262 10 5 /16 flanged BW sched. 80 85 2 11 /32 268 10 9 /16 RF 6
TABLE 5 - STANDARD MATERIALS Item Name Material 4 4 1 Body 1.7335 2 Insert 1.4057 3 Nipple 1.7335 4 Flange 1.7335 CERTIFICATION 3 3 B SPID Desuperheaters are approved by authorized authorities to comply with the requirements of e.g. EN 12516. All data subject to changes. NOTE Dimensions may be subject to change without prior notification. Yarway will provide a certified dimensional drawing upon request. 2 2 1 1 FIGURE 5 A RF A BW TABLE 6 - DIMENSIONS - WEIGHT Water connections Size Weight kg Body Steam connections A mm B mm Size Rating 40 2.7 PN 16/40/64/100 RF (wafer) 40 200 DN 15 PN 16/40/64/100 BW sched. 40 60 flanged BW sched. 80 60 RF 50 3.7 PN 16/40/64/100 RF (wafer) 40 205 DN 15 PN 16/40/64/100 BW sched. 40 65 flanged BW sched. 80 65 RF 80 6.9 PN 16/40/64/100 RF (wafer) 50 227 DN 15 PN 16/40/64/100 BW sched. 40 75 flanged BW sched. 80 75 RF 100 11.8 PN 16/40/64/100 RF (wafer) 60 260 DN 25 PN 16/40/64/100 BW sched. 40 85 flanged BW sched. 80 85 RF 7
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