2-Port Seat Valves with Flange, PN 25

Transcription

1 OEM 2-Port Seat Valves with Flange, PN 25 VVF52...E Spheroidal cast iron EN-GJS LT valve body DN k vs m 3 /h Can be equipped with SQX E- motoric or SKD E- or SKB - electrohydraulic actuators Use For use in district heating, heating, ventilating, and air conditioning systems as a control or safety shutoff valve to DIN For open and closed circuits (mind cavitation). CEQ4373en Building Technologies HVAC Products

2 Type summary Type reference DN k vs [m 3 / h] S v VVF E 0.63 VVF E 0.80 VVF52.5-E.00 VVF E.25 VVF E 5.60 VVF52.5-2E 2.00 VVF E 2.50 VVF E 3.20 VVF52.5-4E 4.00 VVF E 5.00 VVF E VVF E 8.00 VVF E 0.00 VVF E 2.50 VVF E VVF E VVF E DN = Nominal size k vs = Nominal flow rate of cold water (5 30 C) through the fully open valve (H 00 ) by a differential pressure of 00 kpa ( bar) S v = Rangeability k vs / k vr k vr = Smallest k v value, at which the flow characteristic tolerances can still be maintained, by a differential pressure of 00 kpa ( bar) Accessories Type Description ASZ6.5 Electric stem heating element, AC 24 V / 30 W, required for media below 0 C Order Delivery Example: When ordering please give quantity, product name and type reference. 2 2-port valves VVF E Valves, actuators and accessories are packed and supplied separately. The valves are supplied without counter-flanges and without flange gaskets. Spare parts EPDM sealing gland DN 5 40 for VVF52 E (stem-ø 0 mm) Z03 2/8

3 Equipment combinations Valves Actuators SQX E ) SKD E ) 2) SKB 2) H 00 p max p s p max p s p max p s [mm] [kpa] VVF52.5 E VVF52.25 E VVF52.40 E ) 2) Usable up to maximum medium temperature of 50 C Together with actuators SKD...E or SKB... 2-port valves VVF52...E are TÜV approved to DIN and can be used as safety shutoff valves H 00 = Nominal stroke p max = Maximum permissible differential pressure across the valve, valid for the entire actuating range of the motorized valve p s = Maximum permissible differential pressure at which the motorised valve will close securely against the pressure (close off pressure). Actuator overview Type Actuator type Operating voltage Positioning signal Spring return Positioning time Positioning force Data sheet opening closing SQX32.00E AC 230 V 3-position 50 s Motoric SQX62E AC 24 V DC 0 0 V ) 35 s 700 N Q4554 SKD32.50E SKD32.2E SKD62E Electrohydraulic AC 230 V 3-position AC 24 V DC 0 0 V ) 30 s 20 s 0 s 5 s 000 N Q4567 SKB32.50 SKB32.5 SKB82.50 SKB82.5 SKB60 SKB62 Electrohydraulic AC 230 V AC 24 V 3-position DC 0 0 V ) 20 s 2800 N N4564 N4566 ) or DC 4 20 ma Pneumatic actuators Contact your local office or branch for more information. Technical design / mechanical design Valve cross section 4373Z07 Depending on the nominal size, a guided parabolic, perforated or slot plug is used that is directly connected to the valve stem. The seat is screwed to the valve body with the aid of special gland material. The 2-port seat valve does not become a 3-port valve by removing the blank flange! 3/8

4 Sizing Flow diagram 0,0 0,02 0,03 0,04 0,05 0,06 0,08 0, 0,2 p v00 [bar] 0,3 0,4 0,5 0,6 0,8 2 3 SQX...E SKD...E SKB , ,8 4,2 30 8,4 20 5,8 0 8 DN - k vs ,8 2, , , ,7,4, V 00 [m³/h] 3 2 0,8 0,6 0,5 0,4 5-3,2 5-2, ,6 5 -, ,8 5-0,63 p max 0,85 0,6 0,28 0,22 0,7 0,4 0, V 00 [l/s] 0,3 0,08 0,2 0,06 0, 0,08 0,038 0,022 0,06 0,05 0,04 0,07 0,04 0,0 0,03 0,008 0,02 0,006 0,0 0, p v00 [kpa] D07 p max = Maximum permissible differential pressure across the valve, valid for the entire actuating range of the motorised valve p v00 = Differential pressure across the fully open valve and the valve s control path by a volume flow V 00 V & 00 = Volumetric flow through the fully open valve (H 00 ) 00 kpa = bar 0 mwc m 3 /h = l/s water at 20 C Valve flow characteristic 4373D02 Flow k v / k vs 0,8 0,6 0,4 0, % linear % equal percentage n gl = 3 as per VDI / VDE ,2 0,4 0,6 0,8 Stroke H / H 00 4/8

5 Cavitation Cavitation accelerates wear on the valve plug and seat, and also results in undesirable noise. Cavitation can be avoided by not exceeding the differential pressure shown in the flow diagram on page 4, and by adhering to the static pressures shown below P [kpa] 500 ϑ 80 C 60 C 20 C 00 C 80 C 40 C 5 P [bar] p max [kpa] 4382D05 p max = Differential pressure with valve almost closed, at which cavitation can largely be avoided P P 2 P P2 M ϑ = Total pressure (static and dynamic) at inlet = Total pressure (static and dynamic) at outlet = Pump = Water temperature M pmax 4382Z06 Example: Pressure P at valve inlet: 500 kpa (5 bar) Water temperature: 20 C From the diagram above, it can be seen that the maximum permissible differential pressure p max should not exceed 200 kpa (2 bar). Working pressure and medium temperature Working pressure [bar] D Medium temperature [ C] Working pressure staged as per ISO 7268 and EN 333 at medium temperatures of C. As per DIN 4747-: medium temperatures of 0 50 C 5/8

6 Notes Engineering We recommend installation in the return pipe, as the temperatures in this pipe are lower for applications in heating systems, which in turn, extends the stem sealing gland's life. In open circuits the valve plug may seize as the result of scale deposits. In these applications, only the most powerful SKD E or SKB actuators should be used. Further the valve plug should be moved at regular intervals (two to three times per week). A strainer MUST be fitted at the valve inlet Ensure cavitation free flow. To ensure the reliability of the valve, we recommend the fitting of a strainer at the valve inlet also in closed circuits. For media below 0 C, use the electric ASZ6.5 stem heating element to prevent the valve stem from freezing in the sealing gland. For safety reasons, the stem heating element has been designed for AC 24 V / 30 W operating voltage. Mounting Both valve and actuator can easily be assembled at the mounting location. Neither special tools nor adjustments are required. The valve is supplied with Mounting Instructions Orientation Z6 Direction of flow Commissioning When mounting, pay attention to the valve's flow direction symbol. Direction of action: the valve plug closes against pressure Commission the valve only if the actuator has been mounted correctly. Valve stem retracts: valve opens = increasing flow Valve stem extends: valve closes = decreasing flow Maintenance VVF52...E valves require no maintenance. Warning Stem sealing gland When doing service work on the valve / actuator: Deactivate the pump Turn off the power supply to the actuator Close the shuttoff valves Fully relieve the pressure in the pipe system If necessary, disconnect the electrical wires. Before putting the valve into operation again, make certain the actuator is correctly fitted. The glands can be exchanged without removing the valve, provided the pipes are depressurized and cooled off and the stem surface is unharmed. If the stem is damaged in the gland range, replace the entire stem-plug-unit. Contact your local office or branch. 6/8

7 Disposal Before disposal the valve must be dismantled and separated into its various constituent materials. Legislation may demand special handling of certain components, or it may be sensible from an ecological point of view. Current local legislation must be observed. Warranty The technical data given for these applications is valid only in conjunction with the Siemens actuators as detailed under «Equipment combinations». All terms of the warranty will be invalidated by the use of actuators from other manufacturers. Technical data Functional data PN class PN 25 to EN 333 Working pressure to DIN within the permissible medium temperature range according to the diagram on page 5 Flow characteristic 0 30 % % linear equal percentage; n gl = 3 to VDI / VDE 273 Leakage rate % of k vs value to DIN EN 349 Permissible media: water chilled water, cooling water, low temperature hot water, high temperature hot water, water with antifreeze; recommendation: water treatment to VDI 2035 brine Medium temperature ) C Rangeability S v DN 5: DN 25 40: Nominal stroke 20 mm Industry standards Pressure Equipment Directive PED 97/23/EC Pressure Accessories as per article, section 2..4 Fluid group 2 without CE-marking as per article 3, section 3 (sound engineering practice) Materials Valve body spheroidal cast iron EN-GJS LT Stem stainless steel Plug, seat stainless steel Sealing gland brass Gland materials EPDM O-ring Dimensions / Weight Refer to «Dimensions» Flange connections to ISO 7005 ) Electric stem heating element ASZ6.5 required for media below 0 C. 7/8

8 Dimensions Dimensions in mm L3 H D4 H2 D H B K D2 L2 L 4373M0 DN B D D2 D4 K L L2 L3 H H2 H Weight Ø Ø Ø SQX E SKD E SKB [kg] (4x) > 489 > > (4x) > 482 > DN = Nominal size H = Total actuator height plus minimum distance to the wall or the ceiling for mounting, connection, operation, maintenance etc. H = Dimension from the pipe centre to install the actuator (upper edge) H2 = Valve in the «Closed» position means that the valve stem is fully extended 8/ Siemens Switzerland Ltd Subject to alteration