Yarway covers requirements for Desuperheaters, pneumatic actuators, strainers with a wide range of models, sizes and materials to satisfy all the specifications of the power-pulp and paper industry and process gas applications FEATURES Fabricated construction Spring loaded nozzle type Wide range of C v (K v ) capacities available Special nozzle combinations available Pressure class and connections: - ASME B16.34 class 150 to 1500 - EN 1092-1 class PN 25 to 250 - Buttweld connections to ASME B16.25 or DIN 2559 Materials: - ASTM SA 105 / SA 106 Gr.B or P250GH/P235GH Tc2 - ASTM SA 182 F11 / SA 335 P11 or EN 1.7335 - Other materials upon request GENERAL APPLICATION Cooling of process steam or gas, Boiler superheater, Boiler reheater, Turbine bleed steam and Pressure reducing valve TECHNICAL DATA Size: Steam NPS 4 (DN 100) or NPS 6 (DN 150) Water NPS 1-1½ - 2-3 (DN 25-40 - 50-80) www.pentair.com/valves 2014 Pentair Ltd. All Rights Reserved. VCTDS-03071-EN 14/09
YARWAY NARVIK MODEL 60/70 FIG. 1 - MODEL 60 Water inlet flange is available to various standards. Size: NPS 1-1½ - 2-3 (DN 25-40 - 50-80) Steam flange is available to various standards. Size: NPS 4 (DN 100) or NPS 6 (DN 150) Fabricated body available in various materials. Construction in accordance with ASME B16.34 / EN 12516. CE-marking, if required. Body extension pipe in various lengths, depending upon the installation requirements. Spring loaded spray nozzles give fine atomization of injection water. FIG. 2 - NAMEPLATE EXAMPLE 2
YARWAY NARVIK MODEL 60/70 FIG. 3 - MODEL 70 Water inlet flange is available to various standards. Size: NPS 1-1½ - 2-3 (DN 25-40 - 50-80) Steam flange is available to various standards. Size: NPS 4 (DN 100) or NPS 6 (DN 150) Fabricated body available in various materials. Construction in accordance with ASME B16.34 / EN 12516. CE-marking, if required. Body contraction for large diameter piping: Through pipe design. Spring loaded spray nozzles give fine atomization of injection water. Arrangement of nozzles in various directions is possible to enlarge the injected areas. Part of standard delivery: - Weld-o-let - Guiding piece - Welding neck flange - Blind flange - Gasket, studs/nuts 3
The Yarway SLN-Temp Desuperheater is specifically developed for use on low-/medium pressure steam applications. The fluid to be injected is fed to the individual nozzles through tangentially positioned drillings. This results in fluid rotation within the nozzle chamber. At the momentum the valve disc opens the fluid will form a fine hollow cone. Hollow cone atomizers have been proven to be the best for desuperheating applications. The fabricated construction makes it easy adaptable to meet various boiler codes and material specifications. The unit can also be used as a liquid into gas injector for which high grade alloy such as stainless Steel or high nickel alloys are often used. The nozzle components are selected from high grade alloy steels. They are attached by seal welds and no threading is applied to the nozzle housing. The spring loaded nozzles are selected such that the opening is sequentially. This is assures that in all load situations the number of nozzles in service is optimal. Spring ranges and the number of nozzles will be selected in function of this sequential opening/closing, depending upon data supplied by the customer. This allows for tailor made solutions. The SLN-Temp requires a separate water control valve to regulate the quantity of injection water. Yarway will specify the data to size this valve. Upon customer request this component can also be included in the Yarway supply. APPLICATIONS Yarway SLN-Temp Desuperheaters are used for temperature control of: turbine bleed steam - pressure reducing valve outlet steam - process steam and process gasses. SUPERIOR SPRAY NOZZLE Yarway has incorporated the latest technology in the spray nozzle design. Each individual nozzle consists of the following components (Fig. 4). Nozzle body Disc Spring Guide bushing Nut The fluid to be injected enters the nozzle body through tangentially drilled feed holes (A). This positioning results in a rotational movement of the fluid in the nozzle chamber (B). The spring (C) is selected for a certain set pressure. The spring material is an Incoloy grade, a material well suitable within the application range of the SLN-Temp. When the Δp between the injection fluid and the pressure in the main line exceeds this set pressure the disc (D) will lift from its seat. The small, circumferential, opening acts as a flow divider and the fluid will enter the main pipe in the form of a hollow cone. This is desirable as hollow cones are the best for quick conversion from fluid to vapor. The stroke of the disc is pre-set by the guide bushing (E), thus limiting the C v (K v ) value (flow coefficient). Individual nozzles can be combined to form a nozzle head. The nozzle head is designed with a sequential opening of the individual nozzles such that a gradual increase in injection liquid is the result. Smooth control of the injection water quantity results in smooth temperature control of the desuperheated gas. Nozzle heads are calculated, selected and assembled on order specifications. Individual nozzles are replaceable. As all SLN-Temp valves will have an individual identification number, this number guarantees traceability. The minimum set pressure (disc opening) of the spring is 0.7 bar Δp The highest set pressure (disc opening) of the spring is 6.5 bar Δp. FIG. 4 4
CODES AND STANDARDS The SLN-Temp Desuperheater is designed and manufactured in acc. with ASME B16.34 / EN 12516. Upon request it can be manufactured to meet a wide variety of other 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. Definition Q= m 3 / hr. S.G.= kg/dm 3 Δp= bar MULTIPLE NOZZLE HEADS The SLN-Temp Desuperheater may be equipped with a variety of spray nozzles. The uniform body threading accepts spray nozzles with a wide range of C v (K v ) values. Standard configurations are with either 1-2-3 or 4 spray nozzles but special combinations are available, all depending on steam pipe diameter. This feature enables the SLN-Temp Desuperheater to be customized to specific system requirements. Consult Yarway or your local representative for details. For large diameter piping (>DN 450 / 18 ) Yarway may provide a lance design with nozzles staggered to cover the entire corss section of the piping. The injector needs to be supported at the opposite of the entry flange. Yarway will specify the dimensions and tolerances of this counter pocket. See figure 10 for details. SLN - TEMP STANDARD CAPACITY RANGE The Yarway SLN-Temp has a basic selection from 4 sizes of nozzles. Sizing is performed using the data under ordering/sizing data (next page). TABLE 1 Nozzle designation K v value Nozzle designation K v value 12 AA 0.035 21 BB 1.010 12 BB 0.065 27 AA 1.300 12 CC 0.135 27 BB 1.680 16 AA 0.222 27 CC 2.600 16 BB 0.315 27 DD 3.250 16 CC 0.540 27 EE 4.220 21 AA 0.760 H W G W FIG. 5 Each individual nozzle can be equipped with a spring with settings ranging from 0.7 bar ΔP to 6.5 bar ΔP The minimum K v value possible is 0.035. The maximum is limited only by the number of nozzles installed. This is selected by the Yarway sales staff upon clients specification. Flow capacity limitations are: model 60 and 70 with a maximum water flow capacity of 50 m 3 /hr. in continuous service 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 = Injection water mass G ST = Inlet steam mass H 1 = Enthalpy of the inlet steam H 2 = Enthalpy of the outlet steam H W = 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. 5
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: Inlet steam velocity At high steam velocities, water droplets are easily disintegrated. This factor contributes to the overall atomization quality (secondary atomization). The minimum acceptable steam velocity varies as a function of the nozzle size and pipe diameter. In case of doubt, consult Yarway. Water to steam ratio This ratio is determined by dividing G W by G ST. For system steam pressures below 15 bar, this ratio should not exceed 15% for the normal operating conditions. Systems operating between 15 and 25 bar can have a ratio of up to 20%. For higher pressure duties, consult Yarway. Distance to sensor The distance from the injection point to the temperature sensor should be 12 to 15 meters. Systems operating at pressures above 25 bar can have significantly less run to the sensor, consult Yarway. Required straight pipe run The distance from injection point to the first pipe bend is also a function of steam pressure, temperature and nozzle size. Experience has shown that in systems up to 25 bar, 4 to 6 meters, is an acceptable distance. NOTE For gas/fluid mixtures other than steam, different application limits apply. Consult factory. 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 setpoint Steam flow max. t / hr Steam flow normal t / hr Steam flow min. t / hr General Pipe size mm Pipe schedule It is essential not to over specify the required turndown ratio i.e.: Steam flow max. Steam flow min. This may have a negative effect on the controllability over the flow range. Water data Water pressure bar Water temperature C Water flange position FIG. 6 Steam Steam flow line Spraywater must be injected with the direction of the steam flow. Flange bolt holes will straddle with main pipe centerline. Yarway always recommends a strainer with a mesh size of approx. 100 µ (400 µ on request) in the water supply line to protect the SLN-Temp Desuperheater from clogging. 6
Model 60 FIG. 7 TABLE 2 - STANDARD MATERIALS Item Name Material Equivalent 1 + 2 Spray nozzle assembly SS V.A. 9 Body pipe A106 Gr.B P235GH Tc2 A335 P11 1.7335 10 Water flange A105 P250GH 19 Name plate AISI 304 1.4301 24 Steam flange A105 P250GH 33 Reducer A234 WPB P250GH 10 33 19 NOTE Other materials are available upon request. Certification: SLN-Temp Desuperheater is approved by authorized authorities to comply with the requirements of ASME B16.34 / EN 12516. 24 All data subject to changes. Materials and data of units supplied, may deviate from this brochure. Please consult order documents in case of doubt. 9 1 2 Recommended spare parts 7
Model 60 TABLE 3 - DIMENSIONS (mm) Standard length for steam line sizes up to 12 (DN 300) Qmax = 50 m 3 / hr. A 380 B 476 FIG. 8 Water flange Table 4 Option: standard length for steam line sizes 14 (DN 350) and higher A 580 B 676 C 250 M min. 95 N 73.3 x 14 P 78 C Steam flange Table 4 NOTE Dimensions may be subject to change without prior notification. Yarway will provide a certified dimensional drawing upon request. M TABLE 4 - FLANGE CONNECTIONS Qmax = 50 m 3 / hr. Steam flange NPS 4 class 150 class 300 class 600 class 900 class 1500 DN 100 PN 25/40 PN 64 PN 100 PN 160 PN 250 Water flange NPS 1-1½ - 2-3 DN 25-40 - 50-80 Pressure classes as per water data requirements B A N MINIMUM STEAM PIPE SIZE 6 (DN 150) Consult factory for smaller sizes. P Nozzles Tack weld 8
Model 70 FIG. 9 TABLE 5 - STANDARD MATERIALS Item Name Material Equivalent 1 + 2 Spray nozzle assembly SS V.A. 8 Pipe adaptor A105 P250GH 9 Body A106 Gr.B P235GH Tc2 A335 P11 1.7335 10 Water flange A105 P250GH 19 Name plate AISI 304 1.4301 24 Steam flange A105 P250GH 25 Welding neck flange A105 P250GH 26 Guiding piece A106 Gr.B P235GH Tc2 A335 P11 1.7335 27 Weld-o-let A105 P250GH 33 Reducer A234 WPB P250GH 34 Blind flange A105 P250GH 35 Gasket SS/Graphite SS/Graphite 36 Studs/nuts A193 B7/A194 2H Steel 24 10 33 19 1 2 9 27 26 25 8 34 35 36 Recommended spare parts 9
Model 70 TABLE 6 - DIMENSIONS (mm) Standard length for steam line sizes from 20 (DN 500) and up Qmax = 50 m 3 / hr. X 20 22 24 26 28 30 32 34 36 42 56 66 508 559 609 660 711 762 813 864 914 1067 1422 1676 A 454 480 505 530 556 581 607 632 657 734 911 1038 B 838 889 939 990 1041 1092 1143 1194 1244 1397 1752 2006 C 250 M min. 87.32 N 2½ XXS (73.3 x 14) FIG. 10 C NOTE Dimensions may be subject to change without prior notification. Yarway will provide a certified dimensional drawing upon request. M TABLE 7 - FLANGE CONNECTIONS Qmax = 50 m 3 / hr. N Steam flange NPS 4 class 150 class 300 class 600 class 900 class 1500 DN 100 PN 25/40 PN 64 PN 100 PN 160 PN 250 Water flange NPS 1-1½ - 2-3 DN 25-40 - 50-80 Pressure classes as per water data requirements X A Pipe B MINIMUM STEAM PIPE SIZE 20 (DN 500) Consult factory for smaller sizes. Tack weld Detail A Detail A PENTAIR VALVES & CONTROLS www.pentair.com/valves All Pentair trademarks and logos are owned by Pentair Ltd. All other brand or product names are trademarks or registered marks of their respective owners. Because we are continuously improving our products and services, Pentair reserves the right to change product designs and specifications without notice. Pentair is an equal opportunity employer. 2012 Pentair Ltd. All rights reserved. 10