Process Valves Model Selection For product specifications such as maximum operating pressure differentials and operating temperature ranges, refer to the relevent pages of each product. Air One-touch fittings VDW VX VXK Only low wattage, DC type Zero pressure differential operation For dry air VQ0/30 VNA VNB Air VDW VX / /4 ø3., ø4, ø ø, ø, ø0, ø ø0, ø3/", ø ø0, ø3/", ø ø, ø, ø0, ø VXK Vacuum Low vacuum Vacuum Medium vacuum High vacuum VDW A VDW VX VXK /VXV3 VNB VDW VX XL XM/XY XVD Option: V, M Flow rate adjustment VXV3 / /4
Model Selection VX Flange fitting (Nominal dia. A/Upper, Nominal dia. B/Lower) Thread type fitting (Nominal dia. A/Upper, Nominal dia. B/Lower) 0 5 0 5 3 3 3/ / / / VXK P.453 P.7 P. P.57 P.377 P.3 P.7 P.3 P.53 P.559 P.57 VXF VXA VQ0/30 VNA VNB Flange fitting (Nominal dia. A/Upper, Nominal dia. B/Lower) Thread type fitting (Nominal dia. A/Upper, Nominal dia. B/Lower) 0 5 0 5 3 3 3/ / / / P.453 P.7 P. P.377 P.57 P.453 P.7 P.377 Vacuum KF:, 5,,, 3, 0, 00, 0; K3, 0, 00, 0 Best Pneumatics No. 0 Vacuum KF:, 5,,, 3, 0; K3, 0 For VCR /4; For swage lock: /4 XL XM/XY XVD 3 A
Process Valves Model Selection For product specifications such as maximum operating pressure differentials and operating temperature ranges, refer to the relevent pages of each product. Water VDW VX VXK VNB Water One-touch fittings / /4 ø3., ø4, ø Only low wattage, DC type Zero pressure differential operation Water hammer relief Only AC type, MPa or less Heated water Heated water VDW VX VXK VNB VX 4 / /4 Option: E, P Zero pressure differential operation, Option Option: E, P Water hammer relief, Option: D VXK
Model Selection VX Thread type fitting (Nominal dia. A/Upper, Nominal dia. B/Lower) Flange fitting (Nominal dia. A/Upper, Nominal dia. B/Lower) 0 5 0 5 3 3 3/ / / / VXK P.453 P.7 P. P.57 P.377 P.3 P.7 P.3 P.33 P.333 P.57 VXF VXA Flange fitting (Nominal dia. A/Upper, Nominal dia. B/Lower) Thread type fitting (Nominal dia. A/Upper, Nominal dia. B/Lower) 0 5 0 5 3 3 3/ / / / P.7 P. P.377 P.3 P.7 P.3 P.33 P.57 VNB 5
Process Valves Model Selection 3 For product specifications such as maximum operating pressure differentials and operating temperature ranges, refer to the relevent pages of each product. Oil Oil VX VXK VNA VNB / /4 Only low wattage, DC type, Option: A, H Option: A, D, H, N Only AC type,.5 MPa or less Zero pressure differential operation Option: A, D, H, N Water hammer relief, Option: A, D Steam Steam VX VXK VND VX VXK / /4 Option: S, Q Option: S VNA
Model Selection VX Thread type fitting (Nominal dia. A/Upper, Nominal dia. B/Lower) Flange fitting (Nominal dia. A/Upper, Nominal dia. B/Lower) 0 5 0 5 3 3 3/ / / / VXK P.7 P. P.57 P.377 P.333 P.3 P.7 P.3 P.33 P.559 P.57 VXF Flange fitting (Nominal dia. A/Upper, Nominal dia. B/Lower) Thread type fitting (Nominal dia. A/Upper, Nominal dia. B/Lower) 0 5 0 5 3 3 3/ / / / VXA P.7 P. P.377 P.5 P.39 P.3 P.33 VNB VND 7
Process Valves Model Selection 4 For product specifications such as maximum operating pressure differentials and operating temperature ranges, refer to the relevent pages of each product. High pressure compressed air High pressure compressed air 0 / /4 3/ Only low wattage, DC type, 3 MPa or less Only AC type, MPa or less VCH Only G thread type, 5 MPa or less VCH0 Only G thread type Coolant Coolant 0 / /4 3/ SGC SGH VNC VNH VCH VCH0 Chemical liquids, Pure water Chemical liquids, Pure water LV LVM Female thread type, with fittings type available With fittings type, female thread type available 0 / /4 3/ Body ported: ; Base mounted: M Dust collector Dust collector VXF Dedicated for dust collector 0 5 /
Model Selection VX Thread type fitting (Nominal dia. A/Upper, Nominal dia. B/Lower) Flange fitting (Nominal dia. A/Upper, Nominal dia. B/Lower) 5 0 5 3 3 / / / VXK P.57 P.333 P.43 P.43 Thread type fitting (Nominal dia. A/Upper, Nominal dia. B/Lower) Flange fitting (Nominal dia. A/Upper, Nominal dia. B/Lower) 5 0 5 3 3 5 0 / / / / 3 P.575 P.597 VXF P.7 P.7 VXA SGC SGH VNC VNH Thread type fitting (Nominal dia. A/Upper, Nominal dia. B/Lower) Flange fitting (Nominal dia. A/Upper, Nominal dia. B/Lower) 5 0 5 3 3 / / / P.3 P.57 Thread type fitting (Nominal dia. A/Upper, Nominal dia. B/Lower) 5 0 90 00 / 3 3 / 4 P.335 LV LVM VXF 9
Solenoid Valve Flow Rate Characteristics (How to indicate flow rate characteristics). Indication of flow rate characteristics The flow rate characteristics in equipment such as a solenoid valve, etc. are indicated in their specifications as shown in Table (). Table () Indication of Flow Rate Characteristics Corresponding equipment Pneumatic equipment Process fluid control equipment Indication by international standard C, b Kv Other indications S Cv Cv Conformed standard ISO 35: 99 JIS B 390: 000 JIS B 390: 000 Equipment: JIS B 379, 3-, 3- ANSI/(NFPA)T3..3 R-00 IEC0534-: 005 IEC0534--3: 997 JIS B 005-: 0 JIS B 005--3: 004 Equipment: JIS B 47, 47, 473. Pneumatic equipment. Indication according to the international standards () Conformed standard ISO 35: 99 : Pneumatic fluid powercomponents using compressible fluids Determination of flow rate characteristics JIS B 390: 000 : Pneumatic fluid powercomponents using compressible fluids How to test flow rate characteristics () Definition of flow rate characteristics The flow rate characteristics are indicated as a result of a comparison between sonic conductance C and critical pressure ratio b. Sonic conductance C : Value which divides the passing mass flow rate of an equipment in a choked flow condition by the product of the upstream absolute pressure and the density in a standard condition. Critical pressure ratio b : Pressure ratio (downstream pressure/upstream pressure) which will turn to a choked flow when the value is smaller than this ratio. Choked flow : The flow in which the upstream pressure is higher than the downstream pressure and where sonic speed in a certain part of an equipment is reached. Gaseous mass flow rate is in proportion to the upstream pressure and not dependent on the downstream pressure. 0 Subsonic flow Standard condition (3) Formula for flow rate It is described by the practical units as following. When P + 0. b, choked flow P + 0. : Flow greater than the critical pressure ratio : Air in a temperature state of 0 C, absolute pressure 0. MPa (= 00 kpa = bar), relative humidity 5%. It is stipulated by adding the (ANR) after the unit depicting air volume. (standard reference atmosphere) Conformed standard: ISO 77: 990 Pneumatic fluid powerstandard reference atmosphere, JIS B 393: 000: Pneumatic fluid powerstandard reference atmosphere Q = 00 x C 93 (P + 0.) () 73 + T When P + 0. > b, subsonic flow P + 0. P + 0. b P + 0. Q = 00 x C (P + 0.) 93 () b 73 + T
Solenoid Valve Flow Rate Characteristics Q : Air flow rate [L/min (ANR)] C : Sonic conductance [dm 3 /(s bar)], dm 3 (Cubic decimeter) of SI = L (liter). b : Critical pressure ratio [] P : Upstream pressure [MPa] P : Downstream pressure [MPa] T : Temperature [ C] Note) Formula of subsonic flow is the elliptic analogous curve. Flow rate characteristics are shown in Graph () For details, please use the calculation software available from SMC website. Example) Obtain the air flow rate for P = 0.4 [MPa], P = 0.3 [MPa], T = 0 [ C] when a solenoid valve is performed in C = [dm 3 /(s bar)] and b = 0.3. 93 According to formula, the maximum flow rate = 00 x x (0.4 + 0.) x = 00 [L/min (ANR)] 73 + 0 0.3 + 0. Pressure ratio = = 0. 0.4 + 0. Based on Graph (), it is going to be 0.7 if it is read by the pressure ratio as 0. and the flow ratio to be b = 0.3. Hence, flow rate = Max. flow x flow ratio = 00 x 0.7 = [L/min (ANR)] Flow rate ratio 0.9 0. 0.7 0. 0.5 0.4 0.3 0. 0. b = 0. 0. P 0.3 Equipment C, b 0.4 P 0 0 0. 0. 0.3 0.4 0.5 0. 0.7 0. 0.9 Q 0.5 Example 0. VX VXK VXF VXA Pressure ratio (P + 0.) / (P + 0.) Graph () Flow rate characteristics (4) Test method Attach a test equipment with the test circuit shown in Fig. () while maintaining the upstream pressure to a certain level which does not go below 0.3 MPa. Next, measure the maximum flow to be saturated in the first place, then measure this flow rate at 0%, 0%, %, 0% and the upstream and downstream pressure. And then, obtain the sonic conductance C from this maximum flow rate. In addition, calculate b using each data of others and the subsonic flow formula, and then obtain the critical pressure ratio b from that average. Pressure control equipment Pressure gauge or pressure convertor Thermometer Differential pressure gauge or differential pressure converter ød3 3d ød 3d3 ød Flow control valve Air supply Filter Shut off valve 0d3 0d Pipe for measuring temperature Pipe for measuring 3d pressure in the upstream side 0d Equipment for test 3d Pipe for measuring pressure in the downstream side Flow meter Fig. () Test circuit based on ISO 35: 99, JIS B 390: 000
Solenoid Valve Flow Rate Characteristics. Effective area S () Conformed standard JIS B 390: 000: Pneumatic fluid powercomponents using compressible fluids Determination of flow rate characteristics Equipment standards: JIS B 373: Solenoid valve for pneumatics JIS B 379: Silencer for pneumatics JIS B 3-: Fittings for pneumaticspart : Push-in fittings for thermoplastic resin tubing JIS B 3-: Fittings for pneumaticspart : Compression fittings for thermoplastic resin tubing () Definition of flow rate characteristics Effective area S : The cross-sectional area having an ideal throttle without friction deduced from the calculation of the pressure changes inside an air tank or without reduced flow when discharging the compressed air in a choked flow, from an equipment attached to the air tank. This is the same concept representing the easy to run through as sonic conductance C. (3) Formula for flow rate When P + 0. 0.5, choked flow P + 0. Q = 0 x S 93 (P + 0.) (3) 73 + T When P + 0. > 0.5, subsonic flow P + 0. 93 Q = x S (P + 0.) (P P) (4) 73 + T Conversion with sonic conductance C: S = 5.0 x C (5) Q : Air flow rate[l/min(anr)] S : Effective area [mm ] P : Upstream pressure [MPa] P : Downstream pressure [MPa] T : Temperature [ C] Note) Formula for subsonic flow (4) is only applicable when the critical pressure ratio b is the unknown equipment. In the formula () by the sonic conductance C, it is the same formula as when b = 0.5. (4) Test method Attach a test equipment with the test circuit shown in Fig. () in order to discharge air into the atmosphere until the pressure inside the air tank goes down to 0.5 MPa (0. MPa) from an air tank filled with the compressed air at a certain pressure level (0.5 MPa) which does not go below 0. MPa. At this time, measure the discharging time and the residual pressure inside the air tank which had been left until it turned to be the normal values to determine the effective area S, using the following formula. The volume of an air tank should be selected within the specified range by corresponding to the effective area of an equipment for test. In the case of JIS B 379, the pressure values are in parentheses and the coefficient of the formula is.9. V Ps + 0. 93 S =. log0 () () t P + 0. T S : Effective area [mm ] V : Air tank capacity [L] t : Discharging time [s] Ps : Pressure inside air tank before discharging [MPa] P : Residual pressure inside air tank after discharging [MPa] T : Temperature inside air tank before discharging [K] Air supply Thermometer Pressure control equipment Filter Shut off valve Timer (Clock) Pressure recorder Pressure switch Control circuit Air tank Pressure gauge or pressure convertor Rectifier tube in the upstream side Power supply Solenoid valve Equipment for test Rectifier tube in the downstream side Fig. () Test circuit based on JIS B 390: 000
Solenoid Valve Flow Rate Characteristics.3 Flow coefficient Cv factor The United States Standard ANSI/(NFPA)T3..3: R-00R: Pneumatic fluid powerflow rating test procedure and reporting method for fixed orifice components This standard defines the Cv factor of the flow coefficient by the following formula that is based on the test conducted by the test circuit analogous to ISO 35. Q Cv = (7) P (P + Pa) 4.5 T P : Pressure drop between the static pressure tapping ports [bar] P : Pressure of the upstream tapping port [bar gauge] P : Pressure of the downstream tapping port [bar gauge]:p = P P Q : Flow rate [L/s standard condition] Pa : Atmospheric pressure [bar absolute] T : Upstream absolute temperature [K] Test conditions are < P + Pa =.5 ± 0. bar absolute, T = 97 ± 5K, 0.07 bar P 0.4 bar. This is the same concept as effective area A which ISO 35 stipulates as being applicable only when the pressure drop is smaller than the upstream pressure and the compression of air does not become a problem. 3. Process fluid control equipment () Conformed standard IEC0534-: 005: Industrial-process control valves. Part : control valve terminology and general considerations IEC0534--3: 997: Industrial-process control valves. Part : Flow capacity, Section Three- Test procedures JIS B 005-: 0: Industrial-process control valves Part : Control valve terminology and general considerations JIS B 005--3: 004: Industrial-process control valves Part : Flow capacity Section 3: Test procedures Equipment standards: JIS B 47: Solenoid valve for water JIS B 47: Solenoid valve for steam JIS B 473: Solenoid valve for fuel oil () Definition of flow rate characteristics Kv factor: Value of the clean water flow rate represented by m 3 /h that runs through the valve (equipment for test) at 5 to C, when the pressure difference is x 05 Pa ( bar). It is calculated using the following formula: x 0 Kv = Q 5 ρ () P 000 Kv : Flow coefficient [m 3 /h] Q : Flow rate [m 3 /h] P : Pressure difference [Pa] ρ : Density of fluid [kg/m 3 ] (3) Formula of flow rate It is described by the practical units. Also, the flow rate characteristics are shown in Graph (). In the case of liquid: Q = 53Kv P (9) G Q : Flow rate [L/min] Kv : Flow coefficient [m 3 /h] P : Pressure difference [MPa] G : Relative density [water = ] In the case of saturated aqueous vapor: Q = 3Kv P(P + 0.) (0) Q : Flow rate [kg/h] Kv : Flow coefficient [m 3 /h] P : Pressure difference [MPa] P : Upstream pressure [MPa]: P = P P P : Downstream pressure [MPa] 3 VX VXK VXF VXA
Solenoid Valve Flow Rate Characteristics Conversion of flow coefficient: Kv = 0.5 Cv () Here, Cv factor: Value of the clean water flow rate represented by US gal/min that runs through the valve at to 00 F, when the pressure difference is lbf/in (psi) Value is different from Kv and Cv factors for pneumatic purpose due to different test method. (4) Test method Connect the equipment for the test to the test circuit shown in Fig. (3), and run water at 5 to C. Then, measure the flow rate with a pressure difference where vaporization does not occur in a turbulent flow (pressure difference of 0.035 MPa to 0.075 MPa when the inlet pressure is within 0.5 MPa to 0. MPa). However, as the turbulent flow is definitely caused, the pressure difference needs to be set with a large enough difference so that the Reynolds number does not fall below x 05, and the inlet pressure needs to be set slightly higher to prevent vaporization of the liquid. Substitute the measurement results in formula () to calculate Kv. Thermometer Test range Pressure tap Equipment for test Pressure tap Throttle valve in the upstream side Flow meter d 0d d 7d Throttle valve in the downstream side Saturated steam flow rate Q0 [kg/h] (when Kv = ) Fig. (3) Test circuit based on IEC0534--3, JIS B 005--3 00 Upstream pressure P = MPa P = 0. MPa 30 P = 0. MPa Example 0 P = 0.5 MPa 0 5 4 3 P = 0. MPa P = 0. MPa P = 0.3 MPa Pressure differential P [MPa] P = 0.4 MPa Example 0 0.00 0.00 0.003 0.004 0.0 0.0 0.03 0.04 0. Graph () Flow rate characteristics Example ) Obtain the pressure difference when water [5 L/min] runs through the solenoid valve with a Kv =.5 m 3 /h. As the flow rate when Kv = is calculated as the formula: Q0 = 5 x /.5 = 0 [L/min], read off P when Q0 is 0 [L/min] in Graph (). The reading is 0.03 [MPa]. Example ) Obtain the saturated steam flow rate when P = 0. [MPa] and P = 0.00 [MPa] with a solenoid valve with a Kv = 0.05 [m 3 /h]. Read off Q0 when P is 0. and P is 0.00 in Graph (), the reading is 0 kg/h. Therefore, the flow rate is calculated as the formula: Q = 0.05/ x 0 = [kg/h]. 00 30 0 5 4 3 Water flow rate Q0 [L/min] (When Kv = ) 4
Flow Rate Characteristics Note) Use this graph as a guide. In the case of obtaining an accurate flow rate, refer to pages 0 through to 4. For Air Downstream pressure of valve (P) MPa.0 0. 0. 0.4 0. 0 0. 0. 0.3 0.4 Upstream pressure of valve P Approx..0 MPa 0.5 00 00 300 3 0 00 00 300 0 0 0 00 00 00,000,0 3 700 0 700,000,300 0 700 700,000 How to read the graph The sonic range pressure to generate a flow rate of 0 L/min (ANR) is P Approx. 0. MPa for a ø4 orifice and P Approx. 0.5 MPa for a ø3 orifice. 0. 0.7 0. Flow rate Q L/min(ANR) 0.9 00,000,00 Subsonic Critical pressure Sonic ø ø3 ø4 ø5 ø7 ø ø0 ø0 VX VXK VXF VXA For Saturated Steam Downstream pressure of valve (P) MPa.0 0. 0. 0.4 0. 0 (4) (3) (3) (79) () (74) () (70) (0) (4) (5) (5) (5) (5) (54) (43) () (33) (4) (0) 0. 0. 0.3 0.4 Upstream pressure of valve P Approx..0 MPa 0.5 0. 5 0 5 0 5 0 5 0 5 30 35 45 0 0 30 0 30 30 45 35 0 0 How to read the graph The sonic range pressure to generate a flow rate of 5 kg/h is 30 0.7 Flow rate Q kg/h 0. 0.9 0 0 70 0 P Approx. 0.55 MPa for ø orifice and P Approx. 0. MPa for ø3 orifice. The holding heat slightly differs depending on the pressure P, but at 5 kg/h it is approximately 9700 kcal/h. Subsonic Critical pressure Sonic ø ø3 ø4 ø5 ø7 ø ø0 (Port size: /4) ø0 (Port size: 3/, /) 5
Flow Rate Characteristics For Water 30 0 ø0 ø ø7 ø4, ø5 ø3 0 ø Flow rate Q L/min 5 4 3 0. 0.00 (0.00) (0.0054) 0.0 (0.03) 0.05 (0.07) Pressure differential P = (P P) MPa How to read the graph When a water flow of L/min is generated, P Approx. 0.03 MPa for a valve with ø3 orifice.