Designed and constructed to accept pressure drops of the ... docs/Pentair Valves and...

General Description• Incorporates three separate

functions of (1) positive fluid shut-off, (2) regulation and, (3) pressureletdown.

• Designed and constructed to accept pressure drops of the highest magnitude.

• Assured disc-seat alignment throughabove and below seat guidingelement.

• Suitable for modulating or on-offservices.

• Can be provided with pneumatic,hydraulic, or electric actuators.

• Choice of forged body materials.

• Rigorously tested and provensuccessful.

• Successful performance record inscores of utility steam plants.

• Need for reducers can be eliminated.Normally, inlet and outlet endconnections can match existing linesizes.

• Quiet operation resulting from velocity control.

Yarway Turbo-Cascade®High Pressure Control Valve

Copyright © 2009 Tyco Flow Control. All rights reserved. YAWMC-0401-US-0910

Flow ControlYarway is either a trademark or registered trademark of Tyco International Services AG or its affiliates in the United States and/or other countries. All other brand names, product names, or trademarks belong to theirrespective holders.

Designed and constructed to accept pressure drops of the highest magnitude.


Copyright © 2009 Tyco Flow Control. All rights reserved. YAWMC-04012

Potentially destructive erosive forcesexist in high velocity flow through avalve. Their effects can show up asgrooves cut into the valve’s internalsurfaces by an erosive process calledwiredrawing.

Or the pressure drop can causecavitation damage which occurs as aconsequence of the collapse of vaporbubbles in the fluid flow stream. Thebubbles are formed when the fluidpressure is reduced below its vaporpressure at a given temperature. Whenthe system pressure again rises abovethe vapor pressure, the bubblescollapse or implode. Accompanied by a cracking noise, the implosionsrelease vast amounts of energy whichcan tear holes in the walls of the valvebody and destroy internal parts.

The Need for High Pressure ValvesControl of erosive and cavitationalforces is a primary objective of thedesign of high pressure valves. Various stacked disc designs, forinstance, operate on the principle offixed orifices, or flow paths, in parallel.As such a valve opens, the fixed flowareas are progressively uncovered bythe valve plug. Individual flow area does not increase.

These small flow areas act as fluidstrainers and the valve can becomeclogged with debris causing a loss of both flow and control.

Other designs take an approach basedon multiple orifices only one of which isvariable. But this means that the singlevariable orifice must handle the entirepressure differential across the valve.

Yarway’s Design ApproachYarway’s Turbo-Cascade control valve,on the other hand, is based on theprinciple of multiple variable orifices inseries. In this design, which has thebenefit of more than a decade ofrefinement by Yarway engineers, thetotal flow area increases as the valvemodulates toward the open position.Angular passages or flutes, in abushing, direct the fluid through the flowareas or stages which increase in areatoward the valve outlet, thus providinghigher pressure drop on the inlet stagesof the valve and a decreasing pressuredrop in each stage toward the valveoutlet.

In this design, all pressure drops andpressure recovery occur above thevapor pressure, so no cavitation willoccur within the valve.

Turbo-Cascade valves aremanufactured from forged steel bar to assure homogeneity. Connections are available to match inlet and outletline sizes. In many applications,pipeline reducers or expanders can be eliminated.



Inlet Nozzle

Inlet Nozzle

Stem for pneumatic,hydraulic, or electricactuator

Bushing Seal

Body

Cascade Bushing

Cascade Shaft

Piston Lobe

Seat



Liquid Service1. Centrifugal pump

recirculation systems.

2. Pressurizer relief valves.

3. Pressure reducing systems.

How it WorksThe valve divides the fluid flow intomultiple streams and breaks down thehigh pressure in separate stages byinducing 90 degree changes in flowdirection to dissipate energy.

As shown in Figure 2, the total pressuredrop of 2800 psi is broken down into foursuccessive breakdowns of 1297 psi (firststage), 793 psi (second stage), 465 psi(third stage), and 245 psi (fourth stage).

Because the reducing pressure spike atno time goes below the vapor pressureof 35 psia, cavitation will not occur.

Each stage of pressure letdown is at right angles to the following stage.This causes the fluid passing throughthe valve to change flow direction as it cascades down through the valve,dissipating additional energy. Inaddition, each Turbo-Cascade valvehas a fixed orifice in its outlet to provideyet another stage of pressure drop thateliminates the possibility of cavitation in the last stage.

As shown in the cutaway illustration(Figure 3), the cage or bushing throughwhich the cascade piston travels hascast grooves which provides anincrease in flow area as the fluid passesthrough the valve. The cascade shafthas precisely machined lobes thatmove up and down inside the flutedbushing. Varying the position of thelobes within the fluted bushing variesthe area exposed to flow and thuscontrols valve capacity.

To increase flow area further, thediameter of the cascade shaft betweenthe lobes decreases toward the valveoutlet.The increasingly larger flow areaforces higher pressure drop on theupper inlet stages. This is to assure thatthe pressure at all points within thevalve remains above the vapor pressureof the liquid, thus preventing cavitation.

ΔP1 = 1297 psig

1803 psig

ΔP2 = 793 psig

1010 psig

#1Stage

ΔP3 = 465 psig

545 psig ΔP4 = 245 psigPd = 300 psig#4

Stage

#3Stage

#2Stage

= 35 psia

P(psig)

Pv

Pi =3100psig

ValvInlet

e

Typical Applications

To H.P.Heater Controller

positioner

Steam flow fromsuperheater outlet

Desuperheatersprayhead

Thermalshield

Temperaturesensor

Manual bypassvalve

Temperaturetransmitter

B.F. Pump

Gatevalve

Gatevalve

Check valve

Manualisolationvalve

Manualisolation

valve

Turbo-cascadevalve

Turbo-cascade

valve

To H.P. Heater

Flow sensor orifice

Deaerator

Flow-meter

To steam turbine

3-way airsolenoid

valve

Desuperheating Spray Water Control System

Boiler Feed Pump Recirculation Control System

Application ConditionsQb = 600 gpm

Pi = 3100 psig

Pd = 300 psig

DP = 2800 psi

T = 260°F

Pv = 35 psia

G = 0.94

Cv = 11 (4 stages)

Figure 2 - Controlled pressure reduction in Yarway valves helps prevent cavitation, whichcan occur if pressure drops below the vapor pressure of the liquid. Consult Yarway if thepressure at the outlet of the Turbo-Cascade valve is near liquid vapor pressure.



Pressure Reduction CapacityThe Turbo-Cascade valve’s pressure-reduction capability depends on thenumber of pressure-reduction stagesincorporated into the valve for a givenset of conditions. Normally, 600 psi is the upper limit for one stage, twostages are used for 1500 psi, fourstages for 3000 psi and six stages for pressures over 3000 psi.

The cutaway section of the bushing(Figure 3) shows the fluid flow passagesthat provide staged pressurebreakdown. Three stages are illustrated,but up to six can be provided for veryhigh pressure differentials. With thecascade shaft in the closed position inthe bushing (Fig. 3a), drop-tight shut-offcan be achieved. Throttling position anda full open position are shown in Figs.3b and 3c.

With the cascade shaft in the full openposition, the lobes are at mid-point ofthe flutes in the bushing and maximumflow occurs.

Valve ActuationThe valve is designed for compatibilitywith a variety of actuators andpositioners – pneumatic, hydraulic orelectric. A simple form of actuator is a cylinder for on-off operation. Theposition of the actuator is controlled by a solenoid valve that opens or closesthe Turbo-Cascade on signal. Valvesrequiring flow modulation are equippedwith cylinder or diaphragm actuatorsand appropriate positioners.

A hydraulic balancing technique is usedin larger Turbo-Cascade valves for veryhigh pressures to provide automaticoperation. Smaller valves, with up to 2"intervals, are unbalanced and caneasily be operated by pneumatic pistonor diaphragm actuators. In larger sizes,most have balanced pistons so thatpneumatic actuators can be used.

Turbo-Cascade valves are quiet bydesign. The fluted flow configuration of the internals effectively limits fluidvelocity at all points within the valve,

thus preventing a high operating sound-pressure level in even the most severepressure letdown situations.

The design of the valve places theseating surfaces on the upstream orhigh pressure side with flow over theseat. A slight deadband protects theseating surfaces, allowing them toseparate before appreciable flowbegins. These features combine toprovide tight shut-off in high pressureservice over extended periods of time.

Figure 3 – Yarway technique for pressure letdown.

Fig. 3a Fig. 3b Fig. 3c

Seatless Valves for Pressures to 935 psi – Class 250 to 600



Basic Calculations for Sizing Turbo-Cascade Valves

Maximum DP per stage is 750 psi.

1. Flow coefficient or Cv is calculatedusing the basic equation:

Q

Cv = √ DP

SG

where:

Cv = Flow Coefficient

DP = Pressure Drop,Inlet to Outlet

SG = Fluid Specific Gravity

2. Choked flow due to flashing and/orcavitation must also be consideredusing the equation:

DPallowable = FL2[P1 - (rc x Pv)]

where:

FL = Valve Recovery Coefficient(2 stage = 0.93,4 stage = 0.96,6 stage = 0.98)

rc = Critical Pressure Ratio(Use Specific Gravity)

P1 = Inlet Pressure (psia)

Pv = Vapor Pressure (psia)

P2 = Outlet Pressure (psia)

DPtrue = P1 - P2

In sizing, use the smaller of the DPwhich will result in a larger Cv required.

A sample calculation follows:

Flow Q = 248 gpm

Inlet Pressure P1 = 1500 psia

Outlet Pressure P2 = 250 psia

Shut-off Pressure Pso = 1500 psia

Temperature T = 364°F

Vapor Pressure Pv = 164 psia

Specific Gravity SG = 0.88

Critical PressureRatio rc = 0.88

Recovery Factor FL = 0.93(since a 2 stage is chosen for 1250DP)

True DP = P1 - P2

= 1500 - 250

= 1250 psi

DPallowed = FL2[P1 - (rc x Pv)]

= [1500 - (0.88 x 164)]

= 1168 psi

Use the smaller of DPtrue or DPallowed inthe above equation.

Q

Cv = √ DP

SG

248Cv = √ 1168

0.88

Cv = 6.8

Select Class 900 ANSI Valve with 2 stages, Trim Number 0903 (Cv = 7.6).Select desired end connections.

Control valve for ____________________service, Tag No. ____________________ , in accordance with data sheet attached,shall be a Yarway Turbo-Cascade valve,Series 5400, forged steel body,incorporating separate elements fortight shut-off and throttling.

Pressure reduction shall beaccomplished in stages to dissipatepressure and control velocity bydirecting the fluid through a series ofvariable orifices whose individual flowarea increases as the valve is opened.

The fluid pressure breakdown shall takeplace through a series of characterizedpassages between the stem and thebushing whose flow area will be ofsufficient cross-sectional area topreclude the possibility of obstructionby foreign particles. Valve shall operatewith a sound pressure level of 90 dBAor less measured three feet from thevalve, three feet downstream.

How to Specify Turbo-Cascade Valves



Flow Coefficients

Flow Coefficients (Unbalanced Valve)

Class, Trim Cv Kv Stages End Connections1

ANSI No. Standard Inlet/Outlet

900 0941 3.8 3.3 1 1, 11/2

900 0942 7.3 6.3 1 1, 11/2, 2

900 0943 15.9 13.6 1 11/2, 2

900 0944 31.0 26.6 1 2, 3

900 0945 43.0 36.9 1 2, 3

900 0951 94.5 81.1 1 3, 4

900 0901 2.3 2.0 2 1, 11/2

900 0902 4.4 3.8 2 1, 11/2, 2

900 0903 7.6 6.6 2 11/2, 2

900 0904 18.0 15.5 2 2, 3

900 0905 26.5 22.7 2 2, 3

900 0930 56.0 48.1 2 3, 4

1500 1501 2.3 2.0 2 1, 11/2

1500 1502 4.4 3.8 2 1, 11/2, 2

1500 1503 7.6 6.6 2 11/2, 2

1500 1504 18.0 15.5 2 2, 3

1500 1505 26.5 22.7 2 2, 3

1500 1506 1.1 0.9 4 1, 11/2

1500 1507 2.2 1.9 4 1, 11/2, 2

1500 1508 4.8 4.1 4 11/2, 2

1500 1509 9.0 7.7 4 2, 3

1500 1510 16.5 14.2 4 2, 3

2500 2501 2.3 2.0 2 1, 11/2

2500 2502 4.4 3.8 2 1, 11/2, 2

2500 2503 7.6 6.6 2 11/2, 2

2500 2504 18.0 15.5 2 2, 3

2500 2505 26.5 22.7 2 2, 3

2500 2506 1.1 0.9 4 1, 11/2

2500 2507 2.2 1.9 4 1, 11/2, 2

2500 2508 4.8 4.1 4 11/2, 2

2500 2509 9.0 7.7 4 2, 3

2500 2510 16.5 14.2 4 2, 3

2500 2511 0.87 0.75 6 1, 11/2

2500 2512 1.6 1.4 6 1, 11/2, 2

2500 2513 3.5 3.0 6 11/2, 2

2500 2514 7.0 6.0 6 2, 3

2500 2515 13.0 11.2 6 2, 3

Note: 1. Standard inlet and outlet 1" through 2 " flanged or socketweld, 3" and larger buttweld end. Nominal Line Size – Inches.

Flow Coefficients (Balanced Valve)

Class, Trim Cv Kv Stages End ConnectionsANSI No. Inlet Outlet

900 946 94 80.69 1 3,4,6 3,4,6,8

900 947 140 120.17 1 3,4,6,8 3,4,6,8,10

900 948 190 163.10 1 4,6,8 4,6,8,10

900 949 255 218.88 1 6,8,10 6,8,10,12

900 950 360 309.01 1 6,8,10 6,8,10,12

900 916 53 45.49 2 3,4,6 3,4,6,8

900 917 78 66.95 2 3,4,6,8 3,4,6,8,10

900 918 112 96.14 2 4,6,8 4,6,8,10

900 919 148 127.04 2 6,8,10 6,8,10,12

900 920 190 163.10 2 6,8,10 6,8,10,12

1500 1516 53 45.49 2 3,4,6 3,4,6,8

1500 1517 78 66.95 2 3,4,6,8 3,4,6,8,10

1500 1518 112 96.14 2 4,6,8 4,6,8,10

1500 1519 148 127.04 2 6,8,10 6,8,10,12

1500 1520 190 163.10 2 6,8,10 6,8,10,12

1500 1521 27.5 23.61 4 3,4,6 3,4,6,8

1500 1522 42 36.05 4 3,4,6,8 3,4,6,8,10

1500 1523 58 49.79 4 4,6,8 4,6,8,10

1500 1524 81 69.53 4 6,8,10 6,8,10,12

2500 2516 53 45.49 2 3,4,6 3,4,6,8

2500 2517 78 66.95 2 3,4,6,8 3,4,6,8,10

2500 2518 112 96.14 2 4,6,8 4,6,8,10

2500 2519 148 127.04 2 6,8,10 6,8,10,12

2500 2520 190 163.10 2 6,8,10 6,8,10,12

2500 2521 27.5 23.61 4 3,4,6 3,4,6,8

2500 2522 42 36.05 4 3,4,6,8 3,4,6,8,10

2500 2523 58 49.79 4 4,6,8 4,6,8,10

2500 2524 81 69.53 4 6,8,10 6,8,10,12

2500 2526 21 18.03 6 3,4,6 3,4,6,8

2500 2527 31 26.61 6 3,4,6,8 3,4,6,8,10

2500 2528 42 36.05 6 4,6,8 4,6,8,10



Unbalanced Turbo-Cascade Valve

12”MinimumRemovalClearance

PipingClearance

Flow

D

C

A

NominalPipe O.D.

10

23

5

6

26

20

8

7

22

21

2

13, 14

19

24

3

16, 17

9

27

1

11, 12

15

18

4

F

B

EMinimumremovalclearance Piping

clearance

E12"

D

C

A

B

F

NominalPipe O.D.

18

15

11, 12

4

1

27

27

23

5

6

26

20

8

7

22

21

2

13, 14

19

24

3

16, 17

9



Unbalanced Turbo-Cascade Valve

Parts and MaterialsItem Part Material

1 Body/Inlet Connection ASME SA105

2 Actuator Adapter ASME SA105

3 Packing Gland ASME SA105

41 Gland Bushing ASTM A479 Type S21800

51 Cascade Shaft ASME SA479 Gr. 410

6 Cascade Seat ASTM A747 CB7 CU-1 (17-4PH)

7 Spacer Sleeve AISI Type 416 SST

81 Pin Type 18-8 SST

91 Stem ASME SA564 Gr. 630 (17-4)

10 Orifice AISI Type 316 SST

11 Stud ASME SA193 Gr. B7

12 Hex Nut ASME SA194 Gr. 2H

13 Name and Date Plate Type 18-8 SSTl

14 Drive Screws Type 18-8 SST

15 Pipe Plug ASME SA182 Gr. F316

16 Gland Stud ASME SA193 Gr. B7


18 Lantern Ring AISI Type 416 SST

191 Packing Carbon Yarn and Graphite

201 Seal TFE/Egiloy

211 Upper Gasket Spiral Wound Inconel® w/GRAFOIL®

221 Piston Ring AISI Type 410 SST

231 O-ring Fluoraz® (TFE-Propylene)

24 Locknut Carbon Steel

261 Vent Ring 17-4PH SST

271 Belleville Washer 15-7Mo SST AMS5657

Notes:1. Recommended spare parts for service inspection (on hand).

2. Valve constructed in accordance with ANSI B.16.34 and B.16.5 with tolerances per B.16.11

3. Temperature limitation: 500°F.

4. Install any valve with minimum straight piping 6" upstream, 18" downstream. Install any reducers atend of straight runs.

Dimensions, in. [mm]NominalValve Sizes A B C D E

1 [25] 141/16 [357] 61/2 [165] 913/16 [250] 287/16 [722] 91/2 [241]

11/2 [40] 141/16 [357] 73/4 [197] 101/2 [267] 425/16 [1074] 121/2 [318]

2 [50] 17 [432] 81/4 [210] 111/6 [281] 425/16 [1074] 121/2 [318]

Note: Actuator height depends on application and accessories required. Contact your sales representative.



Balanced Turbo-Cascade Valve

H

12”MinimumRemovalClearance

Piston Operator

PipingClearance

D

C

A

B

32

9

4

15

18

11, 12

2

1

33

43

25

42

31

6

5

22

20

7

21

37

8, 13

19

3

16, 17

14

Flow

44

23

45

46

23

34

40

39

38

29

30

Minimumremovalclearance

Pipingclearance

Piston operator

H

12"

D

C

A

B

25

9

32

15

18

2

11, 12

4

1

33

43

42

31

5

6

22

20

7

21

37

8, 13

35, 36

19

14

3

16, 17

30

38

39

29

23

46

45

23

44

40

34



Balanced Turbo-Cascade Valve

Item Part Material

1 Body/Inlet Connection ASME SA105

2 Actuator Adapter ASME SA105

3 Packing Gland AISI 4140

4 Gland Bushing ASTM A479 Type S21801

51 Cascade Shaft ASME SA479 Gr. 410

61 Cascade Seat ASTM A747 CB7 CU-1 (17-4PH)

7 Spacer Sleeve AISI Type 416 SST

8 Nameplate Type 18-8 SST

8A Nameplate Type 18-8 SST

91 Valve Stem ASME SA564 Gr. 630

11 Stud ASME SA193 Gr. B7


13 Drive Screws Type 18-8 SST

14 Jam Nut Carbon Steel

15 Pipe Plug ASME SA105

16 Gland Stud ASME SA193 Gr. B7


18 Lantern Ring AISI Type 416 SST

191 Packing Carbon Yarn and Graphite

201 Seal TFE/Egiloy


Item Part Material

221 Venting Ring 17-4PH SST

231 Piston Ring Type 420 SST


291 Gasket Graph-Lock

301 Pilot Seat AISI Type 410 SST

31 Orifice AISI Type 316 SST

32 Actuator —

331 Bellville Washer 15-7Mo SST AMS5657

341 Pin Type 304 SST

351 Cap Screw Type 18-8 SST

361 Lockwasher Type 410 SST


381 Collar ASTM A583 Type 416 SST

391 Pilot Valve AMS 5385 Stellite

401 Spacer ASME SA479 Gr. 410

41 Warning Label —

42 Pipe Plug Type 18-8 SST

43 Nozzle Stellite

441 Piston Type 17-4PH SST

451 Locknut Type 18-8 SST

461 Stem Retainer ASME SA564 Gr. 630 (17-4)

Dimensions, in. [mm]

Dimensions, in [mm]Nominal A A BValve 1&2 4 Stages 4 Stages 6 1&2 4 6 C D HSize Stages 1500 2500 Stages Stages Stages Stages

3" 213/4 213/4 213/4 28 133/8 133/8 133/8 17 339/16 101/4[552] [552] [552] [711] [340] [340] [340] [432] [852] [260]

255/8 255/8 251/8 321/2 13 13 147/8 171/2 339/16 101/44"[651] [651] [638] [826] [330] [330] [378] [445] [852] [260]

6"203/8 Contact

— —123/8 Contact

—163/4 339/16 101/4

[518] Sales [314] Sales [426] [852] [260]

Actuator height depends on application and accessories required. Contact your sales representative for more information.

Notes:1. Recommended spare parts for service inspection (on hand).

2. Valve constructed in accordance with ANSI B.16.34 & B.16.5 with tolerances per B.16.11

3. Temperature limitation: 500°F.

4. Install any valve with minimum straight piping 6" upstream, 18" downstream. Install any reducers at end of straight runs.

Parts and Materials



Tyco Flow Control (TFC) provides the information herein in good faith but makes no representation as to its comprehensiveness or accuracy. This data sheet is intended only as a guide to TFC products and services. Individuals using this data sheet must exercise their independent judgment in evaluating product selection and determining product appropriateness for their particular purpose and system requirements. TFC MAKES NO REPRESENTATIONS OR WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION ANY WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE WITH RESPECT TO THE INFORMATION SET FORTH HEREIN OR THE PRODUCT(S) TO WHICH THE INFORMATION REFERS. ACCORDINGLY, TFC WILL NOT BE RESPONSIBLE FOR DAMAGES (OF ANY KIND OR NATURE, INCLUDING INCIDENTAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES) RESULTING FROM THE USE OF OR RELIANCE UPON THIS INFORMATION. Patents and Patents Pending in the U.S.and foreign countries. Tyco reserves the right to change product designs and specifications without notice. All registered trademarks are the property of their respective owners. Printed in the USA.

www.tycoflowcontrol.com

Designed and constructed to accept pressure drops of the ... docs/Pentair Valves and...

Documents

Transcript of Designed and constructed to accept pressure drops of the ... docs/Pentair Valves and...