Download - MIL-Power Plant Handbook
MAJOR SYSTEMS
VALVE SELECTION
MATERIAL SELECTION
INSTALLATION & MAINTENANCE
VALVES FOR POWER PLANTS
MIL Controls Limited
A KSB Company
ABOUT THIS HANDBOOK
For the past 20 years, MIL Controls Limited has been one of the premier suppliers of
high speciality Control valves for the Indian Power Plant sector. Over these years our
engineers have gained enormous experience in all aspects of valve design, selection
and maintenance.
The MIL Power Plant Application Handbook tries to translate this experience into a
readily accessible reference tool, the need for which has long been expressed by many
of our clients and associates. The handbook thus encapsulates MIL’s continuing focus on
the power sector.
At a second level, The MIL Power Plant Application Handbook, also serves as a mini
catalogue for MIL’s wide range of products. It offers specific data on Valve Selection and
Operational Characteristics.
© MIL CONTROLS LIMITED, 2007. All rights reserved
MIL Controls Limited. The factory premises at Meladoor near Cochin in Kerala
REFERENCE DOCUMENT: ISA HANDBOOK FOR CONTROL VALVES.
Registered Office & Works.Meladoor , Mala, PIN 680 741, Thrissur District, Kerala, India
Tel: 91 (0)480 2890272, 2890772, 2891773. Fax: 91 (0)480 2890952. Email: [email protected]
Marketing Head Office. N.H. 47, Thaikkattukara P.O., Aluva, PIN 683 106, Ernakulam Dist, Kerala, India
Tel: 91 (0)484-2624955, 2624876. Fax: 91 (0)484-2623331. Email: [email protected]
MIL Controls Limited
A KSB Company
A P P L I C A T I O N H A N D B O O K
C O N T R O L V A L V E S F O R P O W E R P L A N T S
A P P L I C A T I O N H A N D B O O K
C O N T R O L V A L V E S F O R P O W E R P L A N T S
1.1 Company overview .................................................. 8
2.0 Introduction ............................................................. 9
3.1 Major systems ........................................................ 13
3.2 Condensate system ................................................ 14
3.3 Feed Water system ................................................. 17
3.4 Main Steam system ................................................ 22
3.5 Heater Drain system ................................................ 31
4.1 Typical applications. 67.5 MW ................................. 35
4.2 Typical applications. 116 MW .................................. 36
4.3 Typical applications. 210 MW .................................. 38
4.4 Typical applications. 250 MW .................................. 40
4.5 Typical applications.500 MW ................................... 42
5.1 Body material specs ................................................. 47
5.2 Allowable working pressure ..................................... 48
5.3 Trim material selection ............................................ 51
6.1 Handling & Installation ............................................ 55
7.1 Preventive Maintenance ......................................... 61
7.2 Shop Overhaul ....................................................... 62
8.1 MIL 21000 Series .................................................... 67
8.2 MIL 41000 Series .................................................... 68
8.3 MIL 78000 Series .................................................... 69
8.4 MIL 91000 Series .................................................... 70
8.5 Actuators ............................................................... 71
8.6 Accessories ............................................................ 72
9.0 Index & List of Illustrations ........................................ 74
Contents Page
1.0 Contents
7
C O N T R O L V A L V E S F O R P O W E R P L A N T S
A P P L I C A T I O N H A N D B O O K
1.1
Com
pany
ove
rvie
w
MIL Controls Limited. The Assembling Shop, a part of the world class manufacturingfacility at Meladoor near Cochin in Kerala.
A P P L I C A T I O N H A N D B O O K
C O N T R O L V A L V E S F O R P O W E R P L A N T S
Ever since its inception in 1983, MIL has been unrivalled as a supplier ofhigh performance Control Valves to the Indian power sector.
The company, which stamped its class in it’s very first set of major project supplies tothe 210 MW Neyveli TPS (Unit III&IV), the 210 MW MSEB Chandrapur TPS (Stage II),the 210 MW GEB Wanakbori TPS (Stage II) and the 120 MW NALCO CPP (all 5units) way back in 1984-85, has gone on to excel in the design and manufactureof custom-built special application Control Valves to meet the challenging processcontrol requirements in thermal power stations.
In May 2000, MIL achieved another milestone when it unveiled the MATRIXSeries extreme pressure, multi stage, multi path axial flow Control Valves. A productof months of specialised R&D, the MATRIX Series valves have been designed tokill upto 420 Kg/cm2 pressure in 40 stages. This ingenious and unique designhas a progressively declining resistance flow path and is designed to eliminateCavitation and limit Velocity in any severe service condition.
In December 2001, MIL had it’s crown of glory when it became the first Indiancompany to be accredited with the coveted CE marking (refer page 73) for ControlValves, mandatory for exports to the European Union. During 2003-2006, the majorprojects executed by MIL in the Energy Sector includes NPCIL Tarapur 2x540 MW(Unit 3 & 4 ), NPCIL Kaiga/RAPP 2x 210 MW (Kaiga 3&4, RAPP 5&6), NTPC Rihand2x500 MW (Units 3 & 4), NTPC Kahalgaon 3 x500 MW(Units 5,6&7), MPPGCLBirsinghpur 1 x500MW(Unit 5), NTPC Unchahar 1x210MW (Stage-III) etc.
Today MIL is the preferred vendor in the country for the rugged, criticalapplication Control Valves for thermal power stations, be it a 33 MW captivepower plant or a 250/500 MW utility power plant.
With a comprehensive product range, world-class manufacturing and testingfacilities, and a highly skilled work force, we are today fully geared to meet anycritical process control requirements in the power plant sector.
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C O N T R O L V A L V E S F O R P O W E R P L A N T S
2.0 Introduction
Extraordinary demands are placed on Control Valves
used in the Energy Sector. Their operational parameters
vary widely in terms of pressure, pressure drops, flow
rates and temperature.
In addition, other crucial factors like Noise, Cavitation,
Wire drawing, Leakage Class and Flashing also play an
important part in the selection of Control Valves for
power station applications.
POWER PLANT APPLICATIONS
Factors determiningselection of Valves.
1. HIGH TEMPERATURE
2. HIGH PRESSURE
3. HIGH PRESSURE DROP
4. COMBINED HIGH TEMPERATURE, PRESSURE & PRESSURE DROP
5. CONTINUOUS THROTTLING
6. TIGHT SHUT OFF CAPABILITIES
7. AERODYNAMIC NOISE
8. HIGH RANGEABILITY
9. CAVITATION AND FLASHING
A P P L I C A T I O N H A N D B O O K
9
FIG
. 1
. G
EN
ER
AL
B
OIL
ER
(D
RU
M S
TY
LE
) F
LO
W D
IAG
RA
M
10
Thermal Power plant applications4 major systems, their characteristicsand valves used in such applications.
3.1 Major system
s
1. CONDENSATE SYSTEMCondensate Pump Minimum Recirculation Valve
Deaerator Level Control Valve
2. FEED WATER SYSTEMBoiler Feed Pump Minimum Recirculation Valve.
Boiler Feed Water Startup Valve.
Boiler Main Feed Water Control Valve.
3. MAIN STEAM SYSTEMSuperheater Attemperator Spray Valve
Reheater Attemperator Spray Valve.
Turbine Bypass Valves.
Deaerator Pegging Steam Valves.
Soot Blower Steam Pressure Reducing Valves.
PRDS System valves
4. HEATER DRAIN SYSTEMHigh pressure heater drain valves.
Low pressure heater drain valves.
The 4 major systems and critical valves .
13
A P P L I C A T I O N H A N D B O O K
Fig. 2. Condensate System.
Condensate systemThe Condensate system consists ofthe Feed Water Circuit startingfrom the Condenser Hotwell to theDeaerator. The Condenser is a formof heat exchanger that condensesthe exhaust steam of the Turbine.
The exhaust steam of the Turbinewhich is very low in pressure andtemperature passes on its heat tothe cooling water, is condensedand collects in the hotwell. Thelow pressure steam which is veryhigh in volume creates a vacuumwhen it is condensed into water.The vacuum in the Condenserincreases the Thermodynamicefficiency of the cycle. The mostcritical valves which have a bearingon the smooth operation of theplant are Condensate ExtractionPump Minimum Recirculation Valveand Deaerator Level Control Valve.
Condensate Recirculation Valve
The Condensate Pump extractsthe Feed Water from theCondensate Hotwell anddischarges to the Deaerator.
The Condensate Pump musthave a minimum Recirculation orFlow to avoid overheating of thepump and protect it fromCavitation. The CondensateRecirculation Valve recirculateswater from the pump back to theCondenser to ensure minimumRecirculation of the pump. TheCondensate Recirculation Valvehas to absorb the full pressuredrop ie., from pump dischargepressure to the Condenserpressure. Due to very nearsaturated conditions existing inthe downstream side of the valveand relatively higher pressuredrops, the valve is subject toCavitation and Flashing.
Control Valves for this applicationshould also have good shut offcapability to eliminate seatdamage during shut off conditions.Any leakage should be taken intoaccount as a form of lost energy.
3.2
Con
dens
ate
syst
em
14
C O N T R O L V A L V E S F O R P O W E R P L A N T S
3.2 Condensate system
Fig. 3. MIL 78000 Series. CondensateMinimum Recirculation Valve.
T Y P I C A L P A R A M E T E R S
Inlet Pressure: 40- 45 bar( a)
Outlet Pressure: 0.1 bar(a)
Temperature: 40- 50o C
The typical valves for suchapplications have anti Cavitationfeatures which eliminate anypossibility of Cavitation bydropping pressure over stages.
Also material selection shouldbe very discrete in suchapplications taking into accountof highly Erosive Cavitatingconditions. Use of 17-4PH,CA6NM, 440C Martensitic Steelhave yielded excellent results.
Based on the application, typicalAnti-Cavitation solutions are
41002 /41008 Series MultiPath/ Multi Stage design
or 78000 Series Multi Step /Multi Stage design.
Deaerator Level Control Valve.
The apparently mild serviceconditions mislead many Control
Valve manufacturers in thedesign of valves for this service.
The function of this ControlValve is to maintain correctlevels in the Deaerator.
The Deaerator is an open contacttype Feed Water Heater whichpurges any non condensable anddissolved gases. Also theDeaerator acts as a reservoir forFeed Water to smoothen the FeedWater supply at varying loads.
The Feed Water level in theDeaerator also helps inmaintaining the Net PositiveSuction Head (NPSH) of theBoiler Feed Water Pump. TheDALCV has to cater to the widelyvarying flow demand fromstartup conditions tofull load conditions.
Valve selection and design shouldbe based on the following factors:
During the startup the pumpdischarge pressure will be highowing to low flow requirements.Deaerator pressure during thestartup of the plant will be low.
These factors result in the valveworking at very low Cvs and theassociated low lift operations.
Also the relatively higher pressuredrops in these conditons canlead to occurance of Cavitation.
When the pump picks up load,the flow rate increases and thepump discharge pressure goesdown. At the same time, theback pressure in the Deaeratorincreases. This obviouslywarrants a higher flow capacity.
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A P P L I C A T I O N H A N D B O O K
Such extreme conditions call forvalves with exceptionally highRangeability, besides Cavitationprotection at lower flowconditions.
Typical designs for suchapplications are the MIL 41921or the MIL 41621 Series whichincorporate an equal percentagecharacterized Trim which takescare of the high Rangeability.
The basic design is a CageGuided Plug with the Cagehaving characterized ports.
Fig. 4. MIL 41000. Deaerator level Control Valve.
The Cage design combines smallsized, drilled, anti Cavitationholes in the lower portion, andlarger holes at higher lifts.
This design gives the necessaryCavitation protection at lowerlifts and higher flow capacity athigher lifts ensuring very wideRangeability.
3.2
Con
dens
ate
syst
em
T Y P I C A L P A R A M E T E R S
Inlet Pressure: 20- 42 bar (a)
Pressure drop: 7- 42 bar (a)
Temperature: 50 -100 o C
16
C O N T R O L V A L V E S F O R P O W E R P L A N T S
Feed Water systemThe Feed Water system includesthose parts of the system fromDeaerator to the Boiler inlet.
The system consists of Feed Waterpiping, Feed Water pumps, highpressure heaters and theassociated accessories.
The Feed Water pressure is raisedto the Boiler pressure and thetemperature is also raised to nearsaturation conditions by the highpressure heaters and Economisers.
The critical Control Valveapplications in this system areBoiler Feed Pump MinimumRecirculation Valve, Boiler FeedWater Startup Valve & Boiler MainFeed Water Control Valve.
Boiler Feed Pump MinimumRecirculation Valve.
The most critical application in aPower Station is the Boiler FeedPump Minimum RecirculationService. A pump should have aminimum Flow through it totake care of the coolingrequirements of the Pump.
Hence even if the Feed Waterrequirements are very low (due tolow load conditions) the pumpshould handle a minimum flow.To ensure this minimum flow, acertain amount of Flow has tobe recirculated back to theDeaerator as the Flowrequirements of the Boiler maynot be sufficient to satisfy theminimum Recirculationrequirements of the pump.The parameters are obviouslyvery detrimental for any valve tohandle. The valve has to drop apressure of 220-250 bar to 10bar (Deaerator pressure). Also itmay be noted that the outletconditions of the valve are nearsaturation, and hence the valveis very susceptible to highenergy Cavitation and Flashing.
Fig. 5. Boiler Feed Pump Minimum Recirculation System.
3.3 Feed Water system
T Y P I C A L P A R A M E T E R S
Inlet Pressure: 220-250 bar (a)
Outlet Pressure: 10-12 bar (a)
Temperature: 200o C
17
A P P L I C A T I O N H A N D B O O K
3 methods of providingFeed PumpRecirculation.
1. The Modulating Type Systememploys a Modulating Valvewhich throttles the Flow to theminimum required which is afunction of the Flow required bythe Boiler.
Suppose the required minimumRecirculation of the pump is 100tons/hr, and the Boilerrequirement is 90 tons/hr, theminimum Recirculation valve willopen so that it passes 10 tons/hrand the minimum Recirculationcondition is satisfied (90 tons/hrthrough the main line and 10tons/hr through the bypass line.Total flow through the pumpwill be 100 tons/hr ie., 90 + 10).
2. The On/Off System employsan On-Off valve which passes aconstant Recirculation Flow.Suppose the required minimumRecirculation of the pump is 100tons/hr, and the Boilerrequirement is 90 tons/hr, theMinimum Recirculation Valve willfully open so that it passes 100tons/hr so that the minimumRecirculation condition issatisfied. Once the Boilerrequirement goes above 100tons/hr the Recirculation Valvecloses fully since the Boilerrequirement is sufficient to satisfythe minimum Recirculationrequirements of the pump.
3. A third method employed byolder power plants, recirculatesa constant flow, regardless of theplant load. The pressure is killedby Series of multi hole plates.
Of the above methods the idealsystem would be the ModulatingSystem, since it is the most energyefficient . However it exertstaxing demands on Control Valvefunctioning.
Valve are subjected to highpressure drop throttling of verylow flows to full flow conditions.
The high pressure drop throttling atlow lift conditions adverselyaffect Trim durability due to wiredrawing effects and Trim Erosion.
Fig. 6. MIL 78000. Boiler feed pumpminimum Recirculation valve.
3.3
Feed
Wat
er sy
stem
18
C O N T R O L V A L V E S F O R P O W E R P L A N T S
Fig. 7. MIL 91000. Multi stage multi path, axial flow MATRIX Series valve for Boilerfeed pump minimum Recirculation service
In this context, the most costeffective solution is obviouslythe On-Off system.
The typical valve for suchapplication is the MIL 78000Series which incorporates aunique Multi Step, Multi Stagedesign which kills pressure overa number of stages.
The 78000 Series ensures ametal to metal Class V leakage.
Another salient feature is theunique Sliding Collar Seat Ringdesign for Class VIleakageshutoff.
3.3 Feed Water system
MIL’s continuous research andinnovations in Power Plantapplication valves has bornefruit in the successfuldevelopment of the Axial Flow,Multi Stage, Variable Resistancedesign, the MATRIX Series Valvewhich is suitable for aModulating System.
The prototype was developedfor a Pump Recirculationapplication with pressure dropsof 420 bar. The salient feature ofthis design is the wide scope forcustomizing the valve to suitspecific process applications.
19
A P P L I C A T I O N H A N D B O O K
The Trim can be customized tovarious high pressure dropapplications by varying thenumber of stages.
The characteristic can becustomized by reallocating thepressure drop ratio in differentstages. The expanding flowpassages also enhance theRangeability allowing smoothand precise Flow Control even atlow lift operating flow conditions.
Feed Water Regulator Valve
Another critical application in theFeed Water System is the BoilerFeed Water Regulating Valvewhich controls flow to the Boilerfor varying loads of the system.
The valve takes the signal fromthe Feed Water Control whichemploys a three-elementcontrol. The signal is generatedas a function of Drum level,Steam flow and Feed Water flow.
Two kinds of valves are used forFeed Water regulation.
One valve is employed duringthe low load conditions or thestartup conditions of the Boiler.
Another valve is used during fullload conditions. Apparently theapplications may seem similar.
However the selectionphilosophy and design areentirely different for the twovalves. This is because of thedifferent pressure dropconditions existing at the time ofStartup and Full Load.
The typical parameters of LowLoad Feed Water Control Valveand Full Load Feed WaterControl Valve are given below.
Fig. 8. Feed Water Regulating System.
3.3
Feed
Wat
er sy
stem
LOW LOAD FEED WATER VALVE
T Y P I C A L P A R A M E T E R S
Inlet Pressure: 170-200 bar (a)
Outlet Pressure: 30-110 bar (a)
Temperature: 230o C
FULL LOAD FEED WATER VALVE
T Y P I C A L P A R A M E T E R S
Inlet Pressure : 220-250 bar (a)
Outlet Pressure: 210- 230 bar (a)
Temperature: 247o C
20
C O N T R O L V A L V E S F O R P O W E R P L A N T S
Fig. 9. MIL 41008. Multi stage, Low Load, Feed Water regulating valve.
The typical design for low load and full load applications is theMIL 41000 Series Valves which employ Heavy Duty Cage Guidedfeatures.
The Cage Guided design ensures good Throttling Stability andgood Rangeability to cater to widely varying flow conditions.
Where the pressure drop during start-up condition is very high,which can be detrimental in conventional valves, 41008 Series MultiCage design finds its typical application for the low load valve.
This design which features a Multi Stage Pressure Drop Trim, willtake care of the very high pressure drops encountered during start-up conditions where the drum pressure is very low and the pumpdischarge pressure is very high.
3.3 Feed Water system
21
A P P L I C A T I O N H A N D B O O K
Fig. 10. Critical Control Valves in Main Steam Line
Boiler manufacturers employvarious methods like burner tiltmechanism, spray watersystems etc. to control thetemperature of the Main Steam .A poor temperature controlsystem may result in damages toTurbine blades, Superheatertubes, Reheater tubes etc.
Hence Attemperator valves areof critical relevance
The typical problems faced bysuper heater spray ControlValves are throttling instabilityand wide Rangeability.
The design parameters of thespray system include thoseconditions which account forthe excessive heating of theTurbine at full load, with theFeed Water at its maximumtemperature, clean Boiler tubesand most favourable conditions.
Main Steam SystemThe Main Steam System consistsof the steam circuit from the Boileroutlet, Superheater System, SootBlowing system, Turbines,Reheater System to Condenser.The steam fully extracted of theenergy is finally dumped into theCondenser, which is the heat sink.
The most critical application valvesin this system are: SuperheaterSpray Control Valves, SuperheaterSpray Block Valves, Reheater SprayControl Valves, Reheater SprayBlock Valves, Soot Blower PressureControl Valves, PRDS SystemControl Valves, Main SteamPressure Reducing Valves, PRDSSpray Control Valves and DeaeratorPegging Steam Valve.
Super Heater Attemperator Valve
The temperature of the mainsteam coming out of the Boiler isvery critical from the point ofThermodynamic Efficiency ofthe heat cycle and the Turbineblade protection.
3.4
Mai
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C O N T R O L V A L V E S F O R P O W E R P L A N T S
Fig. 12. MIL 41200. Superheater Attemperator valve.
Fig. 11. MIL 41100. Superheater Attemperator valve.
3.4 Main steam
system
23
A P P L I C A T I O N H A N D B O O K
Fig. 13. MIL 41400. SuperheaterAttemperator block valve.
However the above conditionsseldom come into play due todeterioration of Boiler tubes dueto Scale build up and theconsequent heat transfer loss.
Also the situation is furthercompounded by withdrawal ofheat through the Soot Blower.All these factors result in a drasticreduction of spray waterrequirements.
Hence in practice the SprayWater Valve will be seldom takeninto full capacity. The valve will beworking at lower lift conditionsdue to above said reasons.
Another critical factor influencingthe selection of Control Valve isthe Leakage Class.
Any excessive leakage will resultin thermal shocks in SecondarySuperheater Tubes and erosionof Turbine blades.
MIL offers special designs likethe 41100 Series and the 41200Series for such applications.
The 41100 Series features anunbalanced Cage Guided design.This combines the twin benefitsof the good throttling stability ofCage Guided valves with the shutoff capability of single seatedunbalanced designs.
For higher sizes (2” and above)the Actuator thrust requirementswill be very high due to theunbalanced design of the 41100Series design.
The 41200 features a balanceddesign with a novel Static Sealconcept. The 41200 design hasthe same advantages that the41100 Series besides the addedfeature of a balanced plug.
Another application of SpraySystem is the block valve.
The block valves assists the sprayControl Valves effect ing a tightshut off. Another requirement of ablock valve is faster response.Hence the Spray System employs apneumatically operated On OffControl Valve for this application.
The typical MIL designs for blockvalve applications are the 41400Series and the 41200 Series. The41400 design is a Cage Guideddesign where the main plug isassisted by an auxiliary pilotplug to effect tight shut off.
3.4
Mai
n st
eam
syst
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T Y P I C A L P A R A M E T E R S
Inlet Pressure:181-200 bar (a)
Outlet Pressure: 161-180 bar (a)
Temperature: 247o C
24
C O N T R O L V A L V E S F O R P O W E R P L A N T S
Reheater Attemperator Valves
This application is also similar tothe Superheater Spray ControlValve application.
However fluctuations intemperature is not varying as inSuperheater Spray Control.
The Leakage Class is very criticalsince excessive leakage can leadto Erosion of low pressureTurbine blades.
The valve selection depends onthe pressure drop across thevalve. It may be noted here thatreheater pressure is the outletpressure of the high pressureTurbine. The pressure dropacross the valve depends on thesource of the spray water.
Fig. 15. MIL 78000. ReheaterAttemperator Control Valve.
3.4 Main steam
system
The source of the Spray Watercan either be the Feed Waterpump outlet or the inter stagetapping of the pump.
In case of the former, thepressure drop can be as high as100-120 bar, and latter, it can beupto 60-70 bar.
The MIL solution to suchapplications are the 78000Series or the 41008 Series forhigh pressure drops (100-120bar). In the case of moderatepressure drops, it is the 41121Series or the 41221 Series.
The Reheater Spray Block Valveapplication is similar toSuperheater Spray Blockapplications, and the selectionphilosophy is similar to that forSuperheater Spray Block service.
Fig. 14. MIL 41008. ReheaterAttemperator Control Valve.
A P P L I C A T I O N H A N D B O O K
25
Deaerator Pegging Steam Valve
The Deaerator is a direct contacttype heater which removes noncondensable gases like Oxygenand Carbon dioxide from theFeed Water. These gases, if notexpelled, will attack and corrodepiping and Boiler tubes. The hotsteam is mixed with the FeedWater entering the Deaeratorbringing it to saturationtemperature and therebyliberating any undissolved ornon condensable gases.
Steam is supplied to theDeaerator for deaeration ofFeed Water and also to maintaina positive pressure in theDeaearator. Deaerator acts as aFeed Water storage tank to theBoiler Feed Pump. Maintaining ahigher pressure in the Deaeratorhelps in maintaining the NPSHof the pump.
Normally the steam is takenfrom the Auxiliary Steam Headerupto 15% MCR condition.Above this and upto 40% MCR,the steam is taken from the ColdReheat Header (Steam tappedafter the High Pressure Turbine).In full load conditions, steam istaken directly from the Turbineextraction line.Typical valves in this system are:
Fig. 16. Deaerator Pegging Steam System.
3.4
Mai
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eam
syst
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1. DEAERATOR PEGGING FROMAUXILLIARY STEAM HEADER
T Y P I C A L P A R A M E T E R S
Inlet Pressure: 16 bar (a)
Outlet Pressure: 3.5 bar (a)
Temperature: 220o C
2. DEAERATOR PEGGING FROMCOLD REHEAT STEAM HEADER
T Y P I C A L P A R A M E T E R S
Inlet Pressure: 21 bar (a)
Outlet Pressure: 3.6 bar (a)
Temperature: 330o C
26
C O N T R O L V A L V E S F O R P O W E R P L A N T S
Fig. 17. MIL 41003. Deaerator peggingsteam Control Valve
The problems encountered invalve selection for suchapplications are the high noiselevels associated with this valve.MIL offers special low noise Trims(Lo-dB Design) for suchapplications. The 41000 SeriesCage Guided valves with specialLow Noise Trim have been foundexcellent for such services.Additional noise attenuation canbe achieved with double stagepressure drop designs such asdouble Cage or diffuser optionsin the 41000 Series.
Another problem associated withthis service is high exit velocitiesdue to volumetric expansion ofthe steam when the pressuredrops. MIL offers special lownoise cartridges which dividethe pressure drop between thevalve and the cartridges.
The effective pressure drop ratioacross the valve is reduced whichresults in low exit velocities andnoise levels.
3.4 Main steam
system
Soot Blower Valve
The effectiveness of the heattransfer through Boiler tubes isadversely affected by the build upof soot. Also the rapid build up ofsoot in the tubes can lead to thedevelopment of hot spots in theBoiler tubes. The Boiler tubesshould be frequently cleaned toremove the soot. The normalpractice is to use high velocitysteam jets to blow the soot fromthe tubes. The soot removal iseffected through Soot Blowers.Some Soot Blowers use air alsofor the removal of soot.
One of the major challenges here isto select and design a ControlValve for the Steam Soot Blowers.
The problems unique to thisservice are High pressure drop,High noise levels and Thermalcycling of the valve body andvalve internals.
Soot blowing valves are normallyisolated by an upstreamisolation valve. Hence the valveis not subjected to high pressureand temperature when not inservice. However when the SootBlowing is being done, the valveis subjected to very highpressures and temperatures.
T Y P I C A L P A R A M E T E R S
Inlet Pressure - 170 bar (a)
Outlet Pressure - 20 bar (a)
Temperature - 540o C
A P P L I C A T I O N H A N D B O O K
27
Fig. 18. MIL 71114. Soot blower pressure reducing Control Valve
Hence the valve is subjected tothermal cycling which can causeWarpage and Creep in theconventional cast globe valvebodies.
The obvious solution would beto use forged angle bodies orforged inline bodies with specialmulti stage low noise Trims.
Here MIL offers it’s 41114 Series(Cage Guided inline body withdouble stage pressure drop), orit’s 71114 Series (Cage Guidedangle body with double stagepressure drop). The body shallbe forged design and chromemolybdenum steel (ASTM A 182Gr. F22)
3.4
Mai
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28
C O N T R O L V A L V E S F O R P O W E R P L A N T S
PRDS Station Valves.
Apart from steam being used forpower generation and sootblowing, steam is used for otherauxiliary services like glandsealing of Turbines, SteamEjectors in Condensers andDeaerator pegging.
The main steam has to beDesuperheated by reducing itspressure and temperature toutilise the steam for the abovementioned applications.
Fig. 19. Typical Auxiliary PRDS System
The steam Desuperheating iseffected through PRDS stations– Pressure ReducingDesuperheating System.
The PRDS system consists of aDesuperheater pressurereducing valve and atemperature Control Valve. Thepressure reducing valve reducesthe pressure of the steam beforeentry into the Desuperheater.
The temperature Control Valveregulates the spray waterquantity into the Desuperheater.
3.4 Main steam
system
MAIN STEAM PRESSUREREDUCING VALVE
T Y P I C A L P A R A M E T E R S
Inlet Pressure - 170 bar (a)
Outlet Pressure - 16 bar (a)
Temperature - 540o C
TEMPERATURE CONTROL VALVE(SPRAY WATER)
T Y P I C A L P A R A M E T E R S
Inlet Pressure - 185 bar (a)
Outlet Pressure - 16 bar (a)
Temperature - 170o C
A P P L I C A T I O N H A N D B O O K
29
The critical factors that governselection of Main Steam PRV are:High pressure drop, Hightemperature, High noise levelsand Material selection for hightemperature.
MIL offers the 41912 Series or the41914 Series for this application.This design features a CageGuided Trim with special LowNoise multiple holes controllingthe flow. Optional double stagedesign is also available which isvery effective in noise attenuationat higher pressure drop ratios.
For Class V leakage, the 41413Series is the appropriateselection. The 41413 Seriesdesign is a Cage Guided designwhere the main plug is assistedby an auxiliary pilot plug toeffect the tight shut off.
The Cage design includesmultiple holes to attenuate thenoise. The flow direction of thevalve is Over the Plug.
A seat ring - basket diffuser isprovided for effective noiseattenuation at higher pressuredrop ratios.
The temperature Control Valve isanother critical valve coming inthe system. As in the case ofReheater Spray Control Valve,the selection of this valve is alsogoverned by the source of theSpray Water. The source of theSpray Water can either be fromFeed Water Pump outlet or interstage tapping of the pump.
In the case of the former, thepressure drop can be as high as100-120 bar, and in the lattercase, it can be upto 60-70 bar.
The MIL solution to suchapplications are the 78000 Seriesor the 41128 Series for highpressure drops (100-120 bar).
In the case of moderate pressuredrops the design shall be the41121 Series or the 41221 Series.
Fig. 20. MIL 41914 Main Steam Pressure Reducing Valve.
3.4
Mai
n st
eam
syst
em
30
C O N T R O L V A L V E S F O R P O W E R P L A N T S
The Heater Drain SystemThe heater drain system consists ofthe Feed Water heaters coming inthe Condensate system and FeedWater system. The Feed Waterheaters coming in the Condensatesystem are called low pressureheaters which heats the Condensateto saturation point before entry intoDeaerator.
The heaters coming in the FeedWater system are the High pressureheaters which heat the Feed Waterto near saturation point before theentry into Boiler.
The HP heaters and LP heaters arebasically heat exchangers – shell andtubetype. The heating media for HPheaters is the steam extracted fromthe reheat cycle, whereas for LPheaters the steam is extracted fromthe low pressure Turbine.
The heating media, i.e., the steam isintroduced into the heaters, cooledand ultimately condensed back toliquid. The level in the heaters are tobe closely controlled to maintain theThermodynamic efficiency of thesystem. The Condensate in theheaters are at saturation condition,and when the Condensate isdrained to either Deaerator or theCondensate flash tank, the fluidlosses pressure and flashes.
The critical factors that influencethe selection of the valves are:Body and Trim material, Valvesize and Valve flow capacity
Flashing problems encounteredin these services cause materialerosion.
The liquid droplets acceleratedby relatively high velocityvapour phase, impinges on thematerial surface of body andTrim causing heavy wear.
Generally Chrome Molybdenumsteels have exhibited excellentresistance to Flashing Erosion.
Even though ASTM A 217 Gr C5is recommended by some users,it is being increasingly replacedby ASTM A 217 Gr WC9material as C5 has somesignificant manufacturingproblems, in addition to poorweldability, and is thus difficultto weld repair.
Another issue is the selection ofvalve body size. It is alwaysrecommended to select higherbody sizes with a reducedcapacity Trim.
The body size selection criteria isthe outlet Flashing velocity.
MIL offers it’s 21000 Series andthe 4100 Series Valves for theseapplications. The body materialis either WC6 or WC9.
Fig. 21. MIL 21000. Heater Drain Valve
3.5 Heater drain system
A P P L I C A T I O N H A N D B O O K
31
Fig. 23. HP Heaters System
Fig. 22. LP Heaters System
3.5
Hea
ter d
rain
syst
em
32
C O N T R O L V A L V E S F O R P O W E R P L A N T S
Typical InstallationsChoosing the right valve makes all the difference
FE
ED
WA
TE
R C
ON
TR
OL V
ALV
ES
Pro
ject
: TIS
CO
1X
67
.5M
WC
ust
om
er: B
HEL
Mad
ras
No.
Tag
Serv
ice
Mo
del
Size
Rat
ing
*B
od
yC
vPr
.Te
mp
.Q
ty.
1FW
-5LO
W L
OA
D F
EED
WA
TER
FLO
W C
ON
TR
OL
38-7
8101
3 in
.15
00F1
115
17
0 k
g/c
m2
2350
C1
2FW
-2FU
LL L
OA
D F
EED
WA
TER
FLO
W C
ON
TRO
L38
-419
216
x3 in
.15
00W
C6
140
17
0 k
g/c
m2
2350
C1
3FW
-8FU
LL L
OA
D F
EED
WA
TER
FLO
W C
ON
TR
OL
(BY-
PASS
)90
-419
216
x3 in
.15
00W
C6
140
17
0 k
g/c
m2
2350
C1 4.1 Typical applications. 67.5 M
W
1A
S-9
HIG
H C
APA
CIT
Y S
TEA
M P
RES
SUR
E R
EDU
CIN
G38
-419
126
x3 in
.15
00W
C9
120
100
kg/c
m2
5200
C1
2A
S-3
LOW
CA
PAC
ITY
STE
AM
PR
ESSU
RE
RED
UC
ING
38-4
1412
2 in
.15
00W
C9
121
00
kg
/cm
252
00C
1
3BV
-01
CO
MM
ON
BLO
CK
VA
LVE
FOR
PR
DS
SPR
AY
37-2
11X
42
in.
1500
WC
C15
18
5 k
g/c
m2
1750
C1
4SW
-10
HIG
H C
APA
CIT
Y S
PRA
Y W
ATE
R C
ON
TRO
L V
ALV
E38
-781
011
.5 in
.15
00A
105
1.2
18
5 k
g/c
m2
1500
C1
5SW
-4LO
W C
APA
CIT
Y S
PRA
Y W
ATE
R C
ON
TRO
L V
ALV
E38
-781
011
in.
1500
A10
50
.318
5 kg
/cm
215
00C
1
PR
DS V
ALV
ES
Pro
ject
: T
ISC
O 1
X6
7.5
MW
Cu
sto
mer
:BH
EL M
adra
s
* A
NSI
No.
Tag
Serv
ice
Mo
del
Size
Rat
ing
*B
od
yC
vPr
.Te
mp
.Q
ty.
SP
RA
Y &
SO
OT
BLO
WE
R V
ALV
ES
Pro
ject
: T
ISC
O 1
X6
7.5
MW
Cu
sto
mer
: BH
EL T
rich
y
1SD
-5.S
D-6
SH S
PRA
Y C
ON
TRO
L38
-410
242
in.
1500
WC
C8
18
5 k
g/c
m2
2500
C4
2SD
-23
SH S
PRA
Y B
LOC
K38
-414
X1
2 in
.15
00W
CC
401
85
kg
/cm
225
00C
2
3SD
-7IN
TER
MIT
TEN
T BL
OW
DO
WN
VA
LVE
38-7
8001
2 in
.15
00A
105
41
10
kg
/cm
235
00C
2
4S5
7. S
69
SH S
PRA
Y B
YPA
SS V
ALV
ES90
-410
242
.5 in
.15
00W
CC
2018
6 kg
/cm
224
20C
4
5SB
4SO
OT
BLO
WER
STE
AM
PR
.RED
UC
ING
VA
LVE
38-7
0571
2 in
.25
00F1
16
17
3 k
g/c
m2
4130
C2
6SD
-8SO
OT
BLO
WER
STE
AM
PR
.RED
UC
ING
VA
LVE
38-7
0571
2 in
.25
00F2
210
110
kg/c
m2
4200
C4
No.
Tag
Serv
ice
Mo
del
Size
Rat
ing
*B
od
yC
vPr
.Te
mp
.Q
ty.
Cap
acity
67.5
MW
A P P L I C A T I O N H A N D B O O K
35
36
C O N T R O L V A L V E S F O R P O W E R P L A N T S
FEED
CO
NTR
OL V
ALV
ES
Pro
ject
: Ah
emed
abad
Ele
ctri
city
Co
mp
any.
Cu
sto
mer
: BH
EL B
ang
alo
re
1C
V-5
.6FE
ED R
EGU
LATI
NG
VA
LVE
IN H
P BF
P D
ISC
H.L
INE
38-4
1621
2 in
.30
0W
CC
261
5 k
g/c
m2
121
0C
2
2C
V-7
.8FE
ED R
EGU
LATI
NG
VA
LVE
IN H
P BF
P D
ISC
H.L
INE
(FU
LL L
OA
D)
37-4
1612
3 in
.90
0W
C6
9511
5 kg
/cm
212
1oC
2
3C
V-9
.10
FEED
REG
ULA
TIN
G V
ALV
E IN
HP
BFP
DIS
CH
.LIN
E (L
OW
LO
AD
)38
-780
012
in.
900
A10
54
115
kg/c
m2
120
oC
2
* A
NSI
No.
Tag
Serv
ice
Mo
del
Size
Rat
ing
*B
od
yC
vPr
.Te
mp
.Q
ty.
SP
RA
Y V
ALV
ES
Pro
ject
: A
hem
edab
ad E
lect
rici
ty C
om
pan
y.C
ust
om
er:B
HEL
Ban
gal
ore
1C
V-1
1.12
HP
STEA
M B
YPA
SS V
ALV
ES38
-414
126
in.
1500
WC
614
57
0 k
g/c
m2
480o
C2
2C
V-1
3.14
HP
BYPA
SS S
PRA
Y V
ALV
ES37
-211
X5
2 in
.60
0W
CC
461
3 k
g/c
m2
50oC
2
3C
V-1
5.16
LP S
TEA
M B
YPA
SS V
ALV
ES38
-414
218
in.
150
WC
C64
07
kg
/cm
214
7oC
2
4C
V-1
7.1
LP B
YPA
SS S
PRA
Y V
ALV
ES38
-211
X5
1 in
.60
0W
CC
3.8
13
kg
/cm
250
oC
2
No.
Tag
Serv
ice
Mo
del
Size
Rat
ing
*B
od
yC
vPr
.Te
mp
.Q
ty.
1C
V-2
3PR
DS
PR. R
EDU
CIN
G V
ALV
E IN
HP
STEA
M L
INE
TO A
UX
.HD
R.
38-4
1412
2 in
.15
00W
C6
307
0 k
g/c
m2
480o
C1
2C
V-2
4PR
DS
SPR
AY
CO
NTR
OL
VA
LVE
38-7
8003
1 in
.90
0A
105
0.3
11
9 k
g/c
m2
121o
C1
PR
DS V
ALV
ES
Pro
ject
: A
hem
edab
ad E
lect
rici
ty C
om
pan
y.C
ust
om
er:B
HEL
Ban
gal
ore
No.
Tag
Serv
ice
Mo
del
Size
Rat
ing
*B
od
yC
vPr
.Te
mp
.Q
ty.
4.2
Typi
cal a
pplic
atio
ns. 1
16 M
WC
apac
ity 1
16 M
W
A P P L I C A T I O N H A N D B O O K
37
FE
ED
PU
MP
RE
CIR
CU
LA
TIO
N V
ALV
ES
Pro
ject
: Ah
emed
abad
Ele
ctri
city
Co
mp
any.
Cu
sto
mer
: BH
EL B
ang
alo
re
1C
V-2
5.26
.27
REC
IRC
ULA
TIO
N V
ALV
E FO
R H
P BF
P37
-780
031
.5 in
.90
0A
105
4.5
11
5 k
g/c
m2
122o
C3
2C
V-2
8.29
.30
REC
IRC
ULA
TIO
N V
ALV
E FO
R L
P BF
P37
-211
X5
1in
.60
0W
CC
3.8
18
kg
/cm
212
2oC
3
No.
Tag
Serv
ice
Mo
del
Size
Rat
ing
*B
od
yC
vPr
.Te
mp
.Q
ty.
* A
NSI
HE
ATE
R D
RA
IN V
ALV
ES &
CO
ND
EN
SA
TE
SYSTE
M V
ALV
ES
Pro
ject
: A
hem
edab
ad E
lect
rici
ty C
om
pan
y.C
ust
om
er:B
HEL
Ban
gal
ore
1C
V-1
MA
IN C
ON
DEN
SATE
CO
NTR
OL
VA
LVE
38-4
1621
6 in
.30
0W
CC
360
13
kg
/cm
248
oC
1
2C
V-2
MIN
. FLO
W R
ECIR
CU
LATI
ON
CO
NTR
OL
VA
LVE
37-4
1612
2 in
.30
0W
CC
25
13
kg
/cm
248
oC
1
3C
V-3
EXC
ESS
RET
UR
N C
ON
TRO
L V
ALV
E37
-416
212
in.
300
WC
C65
13
kg
/cm
248
oC
1
4C
V-4
DEA
ERA
TOR
OV
ERFL
OW
TO
DM
STO
RA
GE
TAN
K38
-414
X1
3 in
.15
0W
CC
155
7 k
g/c
m2
120
oC
1
5C
V-1
9PR
ESSU
RE
RED
UC
ING
VA
LVE
TO D
EAER
ATO
R38
-416
213
in.
150
WC
C95
7 k
g/c
m2
147
oC
1
6C
V-2
0PR
ESSU
RE
RED
UC
ING
VA
LVE
TO D
EAER
ATO
R38
-416
218
in.
150
WC
C50
07
kg
/cm
214
7oC
1
7C
V-2
1.22
PREH
EATE
R IN
LET
CO
NTR
OL
VA
LVE
37-4
1621
4 in
.30
0W
CC
225
13
kg
/cm
211
8oC
2
8C
V-3
1N
OR
MA
L M
AK
E-U
P V
ALV
E37
-211
251
in.
600
CF8
M6
10
kg
/cm
240
oC
1
9C
V-3
2D
UM
P M
AK
E-U
P V
ALV
E38
-211
252
in.
600
CF8
M46
10
kg
/cm
240
oC
1
No.
Tag
Serv
ice
Mo
del
Size
Rat
ing
*B
od
yC
vPr
.Te
mp
.Q
ty.
4.2 Typical applications. 116 MW
Cap
acity
116
MW
38
C O N T R O L V A L V E S F O R P O W E R P L A N T S
FEED
CO
NTR
OL V
ALV
ES
Pro
ject
: R
aich
ur
TP
S U
nit
IVC
ust
om
er: B
HEL
Mad
ras
1FW
-FC
V-1
FULL
LO
AD
FEE
D W
ATE
R F
LOW
CO
NTR
OL
(MA
IN&
BYPA
SS)
38-4
1921
12
x8 in
.25
00W
C6
575
28
6 k
g/c
m2
250
oC
2
2FW
-FC
V-2
LOW
LO
AD
FEE
D W
AT
ER F
LOW
CO
NT
RO
L38
-414
126
x4 in
.25
00W
C6
452
85
kg
/cm
225
0oC
1
* A
NSI
No.
Tag
Serv
ice
Mo
del
Size
Rat
ing
*B
od
yC
vPr
.Te
mp
.Q
ty.
PR
DS V
ALV
ES
Pro
ject
: R
aich
ur
TP
S. U
nit
IVC
ust
om
er:B
HEL
Mad
ras
1M
SPC
V-1
AU
X.P
RD
S 10
0%ST
EAM
PR
. CO
NTR
OL
VA
LVE
38-4
1412
6x3
in.
25
00
SPL
WC
950
16
5 k
g/c
m2
540o
C1
2M
SPC
V-2
AU
X.P
RD
S 10
%ST
EAM
PR
. CO
NTR
OL
VA
LVE
38-4
1012
2 in
.2
50
0SP
LW
C9
61
65
kg
/cm
254
0oC
1
3SP
TCV
-1A
UX
.PR
DS
100%
SPR
AY
FLO
W C
ON
TRO
L V
ALV
E38
-781
021
.5 in
.25
00A
105
2.4
28
6 k
g/c
m2
250o
C1
4SP
TCV
-2A
UX
.PR
DS
10%
SPR
AY
FLO
W C
ON
TRO
L V
ALV
E38
-781
011
in.
2500
A10
50
.32
86
kg
/cm
225
0oC
1
5V
2505
111
BLO
CK
VA
LVE
ON
SPR
AY
WA
TER
TO
AU
X. P
RD
S37
-211
X4
2 in
.25
00W
CC
152
86
kg
/cm
225
0oC
1
No.
Tag
Serv
ice
Mo
del
Size
Rat
ing
*B
od
yC
vPr
.Te
mp
.Q
ty.
SP
RA
Y &
SO
OT
BLO
WE
R V
ALV
ES
Pro
ject
: U
nch
ahar
TP
S 2
x21
0 M
WC
ust
om
er:B
HEL
Tri
chy
1SD
-4SH
STA
GE
I BLO
CK
38-4
10X
46
x4 in
.25
00W
CC
195
26
5 k
g/c
m2
260o
C2
2SD
-5.6
.7.8
SH S
TAG
E I C
ON
TRO
L38
-410
242
.5 in
.25
00W
CC
3026
5 kg
/cm
226
0oC
8
3SD
-9SH
STA
GE
I I B
LOC
K38
-410
X4
2.5
in.
2500
WC
C60
26
5 k
g/c
m2
260o
C2
4SD
-10.
11.1
2.13
SH S
TAG
E II
CO
NTR
OL
38-4
1024
1.5
in.
2500
WC
C3
.82
65
kg
/cm
226
0oC
8
5SD
-14
RH
BLO
CK
CO
MM
ON
38-4
10X
42
.5 in
.25
00W
CC
602
65
kg
/cm
226
0oC
2
6SD
-15.
16.1
7.18
RH
BLO
CK
BR
AN
CH
38-4
10X
41
.5 in
.25
00W
CC
402
65
kg
/cm
226
0oC
8
7SD
-19.
20.2
1.22
RH
CO
NTR
OL
38-7
8103
1.5
in.
2500
A10
53
.62
65
kg
/cm
226
0oC
8
8PC
V-8
502A
.BSO
OT
BLO
WER
STE
AM
PR
.RED
UC
ING
VA
LVE
38-4
1012
2 in
.25
00F1
125
185
kg/c
m2
440o
C4
No.
Tag
Serv
ice
Mo
del
Size
Rat
ing
*B
od
yC
vPr
.Te
mp
.Q
ty.
4.3
Typi
cal a
pplic
atio
ns. 2
10 M
WC
apac
ity 2
10M
W
A P P L I C A T I O N H A N D B O O K
39
FE
ED
PU
MP
RE
CIR
CU
LA
TIO
N V
ALV
ES
Pro
ject
: R
op
ar T
PS
Cu
sto
mer
: BH
EL H
yder
abad
1FE
ED P
UM
P M
INIM
UM
REC
IRC
ULA
TIO
N37
-781
034
x2 in
.25
00A
105
152
60
kg
/cm
225
0oC
2
No.
Tag
Serv
ice
Mo
del
Size
Rat
ing
*B
od
yC
vPr
.Te
mp
.Q
ty.
HE
ATE
R D
RA
IN V
ALV
ES &
CO
ND
EN
SA
TE
SYSTE
M V
ALV
ES
Pro
ject
: V
ijaya
wad
a T
PS
Stag
e II
Un
it V
&V
IC
ust
om
er:B
HEL
Del
hi
1P
AS-
1PE
GG
. STE
AM
FR
OM
AU
X. S
TEA
M H
EAD
ER T
O D
EAER
ATO
R38
-419
126
in.
300
WC
C30
02
0 k
g/c
m2
230
oC
2
2PC
R-1
PEG
G. S
TEA
M F
RO
M C
RH
TO
DEA
ERA
TOR
38-4
1912
10 in
.60
0W
CC
430
48
kg
/cm
235
0oC
2
3D
R-2
HPH
-6 N
OR
MA
L D
RA
IN T
O H
PH-5
38-4
1321
3 in
.60
0W
C6
564
8 k
g/c
m2
215
oC
2
4D
R-6
HPH
-6 N
OR
MA
L D
RA
IN T
O D
EAER
ATO
R38
-413
213
in.
600
WC
656
48
kg
/cm
221
5oC
2
5D
R-9
HPH
-6 N
OR
MA
L D
RA
IN T
O F
LASH
BO
X-2
38-4
1321
3 in
.60
0W
C6
564
8 k
g/c
m2
215
oC
2
6D
R-1
2H
PH-5
NO
RM
AL
DR
AIN
TO
DEA
ERA
TOR
38-4
1321
4 in
.30
0W
C6
902
0 k
g/c
m2
180
oC
2
7D
R-1
5H
PH-5
NO
RM
AL
DR
AIN
TO
FLA
SH B
OX
-238
-413
214
in.
300
WC
690
20
kg
/cm
218
0oC
2
8D
R-1
7LP
H-3
NO
RM
AL
DR
AIN
TO
LPH
-238
-416
213
in.
300
WC
C14
08
kg
/cm
213
0oC
2
9D
R-2
0LP
H-5
NO
RM
AL
DR
AIN
TO
FLA
SH B
OX
-137
-416
214
in.
300
WC
C22
58
kg
/cm
213
0oC
10D
R-2
2LP
H-2
DR
AIN
TO
LPH
-138
-416
218
in.
300
WC
C57
58
kg
/cm
210
0oC
2
11D
R-2
5LP
H-2
DR
AIN
TO
FLA
SH B
OX
-137
-416
218
in.
300
WC
C57
58
kg
/cm
210
0oC
2
12D
R-4
1D
EAER
ATO
R O
VER
FLO
W T
O D
RA
IN T
AN
K38
-416
X1
10 in
.30
0W
CC
1000
11
kg
/cm
217
0oC
2
13C
D-1
4M
AIN
CO
ND
ENSA
TE38
-416
2110
in.
300
WC
C9
00
25
kg
/cm
255
oC
2
14C
D-2
3C
ON
DEN
SATE
EX
CES
S R
ETU
RN
38-4
1612
6x4
in.
300
WC
C14
52
5 k
g/c
m2
55oC
2
15C
D-1
9C
ON
DEN
SATE
MIN
IMU
M R
ECIR
CU
LATI
ON
37-7
8003
6 in
.30
0A
105
702
5 k
g/c
m2
55oC
2
16C
D-7
8H
P D
RA
INS
MA
NIF
OLD
SPR
AY
37-2
11X
51
in.
300
WC
C12
25
kg
/cm
255
oC
2
17D
M-1
DM
MA
KE-
UP
TO H
OTW
ELL
(LC
)37
-416
112
in.
300
CF8
M30
10
kg
/cm
250
oC
2
18D
M-2
DM
MA
KE-
UP
TO H
OTW
ELL
(HC
)37
-416
113
in.
300
CF8
M60
10
kg
/cm
250
oC
2
19C
D-4
7C
ON
DEN
SATE
FO
R V
ALV
E G
LAN
D S
EALI
NG
38-4
1621
1.5
in.
300
WC
C14
25
kg
/cm
255
oC
2
No.
Tag
Serv
ice
Mo
del
Size
Rat
ing
*B
od
yC
vPr
.Te
mp
.Q
ty.
4.3 Typical applications. 210 MW
Cap
acity
210
MW
40
C O N T R O L V A L V E S F O R P O W E R P L A N T S
FEED
CO
NTR
OL V
ALV
ES
Pro
ject
: C
ESC
Bu
dg
e B
ud
ge
TP
S. 2
*2
50
MW
Cu
sto
mer
: BH
EL D
elh
i
107
28.1
&2
FULL
LO
AD
FEE
D W
ATE
R F
LOW
CO
NTR
OL
(MA
IN&
BYPA
SS)
38-4
1921
14x1
0in.
2500
WC
690
033
0 kg
/cm
224
8oC
4
27
28
.3LO
W L
OA
D F
EED
WA
TER
FLO
W C
ON
TR
OL
38-4
1921
6x4
in.
2500
WC
622
53
30
kg
/cm
224
8oC
2
No.
Tag
Serv
ice
Mo
del
Size
Rat
ing
*B
od
yC
vPr
.Te
mp
.Q
ty.
PR
DS V
ALV
ES
Pro
ject
: B
SES
DA
HA
NU
2x2
50
MW
Cu
sto
mer
:BH
EL B
ang
alo
re
1A
S-2
2M
S PR
DS
STEA
M C
ON
TRO
L38
-414
126
x4in
.2
50
0SP
LW
C9
110
16
9 k
g/c
m2
545o
C2
2FD
-22
MS
PRD
S SP
RA
Y C
ON
TRO
L38
-780
021
.5in
.2
50
0SP
LA
105
2.4
26
7 k
g/c
m2
170o
C2
3FD
-23
MS
PRD
S SP
RA
Y C
ON
TRO
L38
-410
241
.5in
.25
00W
CC
62
67
kg
/cm
217
0oC
2
4A
S-3
2C
RH
STE
AM
PR
DS
38-4
1012
2.5
in.
600
WC
C20
48
kg
/cm
236
0oC
2
5FD
-29
CR
H P
RD
S SP
RA
Y C
ON
TRO
L38
-780
011
in.
2500
A10
50
.32
67
kg
/cm
217
0oC
2
6FD
-30
CR
H P
RD
S SP
RA
Y C
ON
TRO
L38
-780
011
in.
2500
A10
50
.32
67
kg
/cm
217
0oC
2
No.
Tag
Serv
ice
Mo
del
Size
Rat
ing
*B
od
yC
vPr
.Te
mp
.Q
ty.
SP
RA
Y &
SO
OT
BLO
WE
R V
ALV
ES
Pro
ject
: B
SES
DA
HA
NU
2x2
50
MW
Cu
sto
mer
:BH
EL T
rich
y
1SD
-4SH
SPR
AY
STA
GE
I BLO
CK
38-4
14X
16
in.
2500
WC
624
02
62
kg
/cm
226
0oC
2
2SD
-5 T
O S
D-8
SH S
TAG
E I S
PRA
Y C
ON
TRO
L38
-410
242
.5in
.25
00W
C6
301
82
kg
/cm
226
0oC
8
3SD
-9SH
STA
GE
II S
PRA
Y B
LOC
K38
-414
X1
3in
.25
00W
C6
752
62
kg
/cm
235
0oC
2
4SD
-10
TO S
D-1
3SH
STA
GE
II S
PRA
Y C
ON
TRO
L38
-410
241
.5in
.25
00W
C6
81
82
kg
/cm
235
0oC
8
5SD
-14
RH
SPR
AY
MA
IN B
LOC
K38
-414
X1
3in
.25
00W
C6
302
82
kg
/cm
235
0oC
2
6SD
-15
TO S
D-1
8R
H B
RA
NC
H B
LOC
K38
-211
X4
2in
.25
00W
C6
152
82
kg
/cm
235
0oC
8
7SD
-19
TO S
D-2
2R
H S
PRA
Y C
ON
TRO
L38
-780
032
in.
2500
F11
3.5
18
2 k
g/c
m2
350o
C8
8SD
-23
SOO
T BL
OW
ER S
TEA
M P
R.R
EDU
CIN
G V
ALV
E38
-705
712
in.
2500
F22
131
82
kg
/cm
245
0oC
2
No.
Tag
Serv
ice
Mo
del
Size
Rat
ing
*B
od
yC
vPr
.Te
mp
.Q
ty.
4.4
Typi
cal a
pplic
atio
ns. 2
50 M
WC
apac
ity 2
50 M
W
A P P L I C A T I O N H A N D B O O K
41
4.4 Typical applications. 250 MW
FE
ED
PU
MP
RE
CIR
CU
LA
TIO
N V
ALV
ES
Pro
ject
: K
oth
ag
ud
em
TPS, 2
*250 M
W C
ust
om
er:
BH
EL
Hyd
era
bad
1FE
ED
PU
MP
MIN
IMU
M R
EC
IRC
ULA
TIO
N3
7-7
81
03
4x2
in
.2
50
0A
10
51
52
60
kg/
cm2
25
0oC
2
HE
ATE
R D
RA
IN &
CO
ND
EN
SA
TE
SYSTE
M V
ALV
ES
Pro
ject
: K
oth
ag
ud
em
TPS, 2
*250 M
WC
ust
om
er:
BH
EL D
elh
i
1A
S-2
PEG
G. S
TEA
M F
RO
M A
UX
. STE
AM
HEA
DER
TO
DEA
ERA
TOR
38-4
1912
8 in
.30
0W
CC
315
14
kg
/cm
222
0oC
2
2C
RH
-2PE
GG
. STE
AM
FR
OM
CR
H T
O D
EAER
ATO
R38
-419
1210
in
.60
0W
CC
500
48
kg
/cm
236
0oC
2
3D
R-2
HPH
-6 N
OR
MA
L D
RA
IN T
O H
PH-5
38-4
1521
3 in
.60
0W
C6
504
8 k
g/c
m2
215
oC
2
4D
R-6
HPH
-6 A
LT.
DR
AIN
TO
DEA
ERA
TOR
38-4
1921
3 in
.60
0W
C6
504
8 k
g/c
m2
215
oC
2
5D
R-9
HPH
-6 A
LT. D
RA
IN T
O H
P FL
ASH
TA
NK
37-4
1921
3 in
.60
0W
C6
564
8 k
g/c
m2
215
oC
2
6D
R-1
3H
PH-5
NO
RM
AL
DR
AIN
TO
DEA
ERA
TOR
38-4
1521
4 in
.30
0W
C6
120
20
kg
/cm
217
5oC
2
7D
R-1
6H
PH-5
ALT
. DR
AIN
TO
HP
FLA
SH T
AN
K37
-419
214
in.
300
WC
612
02
0 k
g/c
m2
175
oC
2
8D
R-1
9LP
H-3
NO
RM
AL
DR
AIN
TO
LPH
-238
-415
214
in.
150
WC
C17
08
kg
/cm
213
0oC
2
9D
R-2
2LP
H-3
ALT
. DR
AIN
TO
LP
FLA
SH T
AN
K37
-416
214
in.
150
WC
C17
08
kg
/cm
213
0oC
2
10D
R-2
5LP
H-2
NO
RM
AL
DR
AIN
TO
LPH
-138
-415
218
in.
150
WC
C57
58
kg
/cm
210
5oC
2
11D
R-2
8LP
H-2
ALT
. DR
AIN
TO
LP
FLA
SH T
AN
K37
-416
218
in.
150
WC
C57
58
kg
/cm
210
5oC
2
12D
R-3
8D
EAER
ATO
R O
VER
FLO
W T
O L
P FL
ASH
TA
NK
38-4
19X
13
in.
300
WC
C10
01
1 k
g/c
m2
170
oC
2
13C
D-1
4&C
D-1
7M
AIN
CO
ND
ENSA
TE C
ON
TRO
L38
-415
2112
in
.30
0W
CC
900
27
kg
/cm
255
oC
4
14C
D-2
5C
ON
DEN
SATE
EX
CES
S PU
MP
MIN
. REC
IRC
ULA
TIO
N37
-780
033
in.
600
A10
545
27
kg
/cm
255
oC
2
15C
D-2
1EX
CES
S C
ON
DEN
SATE
DU
MP
CO
NTR
OL
38-4
1612
6x3
in
.30
0W
CC
952
7 k
g/c
m2
55oC
2
16C
D-5
3H
P D
RA
INS
FLA
SH T
AN
K S
PRA
Y37
-211
X5
1 in
.30
0W
CC
1,7
30
kg
/cm
255
oC
2
17C
D-5
8EM
ERG
ENC
Y M
AK
E-U
P TO
CO
ND
ENSA
TE H
OTW
ELL
37-4
1612
3 in
.15
0W
CC
958
kg
/cm
255
oC
2
18D
M-2
(LO
W)
DM
MA
KE-
UP
TO H
OTW
ELL
(LC
)37
-415
123
in.
300
CF8
M45
8 k
g/c
m2
40oC
2
19D
M-5
(HIG
H)
DM
MA
KE-
UP
TO H
OTW
ELL
(HC
)37
-416
124
in.
150
CF8
M12
08
kg
/cm
240
oC
2
Cap
acity
250
MW
42
C O N T R O L V A L V E S F O R P O W E R P L A N T S
* A
NSI
4.5
Typi
cal a
pplic
atio
ns. 5
00 M
WC
apac
ity 5
00 M
W
FEED
CO
NTR
OL V
ALV
ES
Proj
ect :
NTP
C T
alch
er T
PS 2
x500
MW
STP
PC
usto
mer
: Kel
tron
Con
trol
s
No.
Tag
Serv
ice
Mo
del
Size
Rat
ing
*B
od
yC
vPr
.Te
mp
.Q
ty.
1FC
V-0
65
7LO
W L
OA
D F
EED
WA
TER
FLO
W C
ON
TR
OL
37-4
1512
12
x8 in
.25
00C
547
53
60
kg
/cm
220
0oC
2
SP
RA
Y &
SO
OT
BLO
WE
R V
ALV
ES
Proj
ect :
NTP
C R
ihan
d TP
S 2x
500
MW
STP
P(U
nit 3
&4)
Cus
tom
er:B
HEL
Tric
hy
No.
Tag
Serv
ice
Mo
del
Size
Rat
ing
*B
od
yC
vPr
.Te
mp
.Q
ty.
1SD
35
SH C
OM
MO
N L
INE
SPR
AY
BLO
CK
38-4
14X
16
2500
WC
C23
035
618
52
2SD
36
TO S
D 3
9SH
BR
AN
CH
LIN
E SP
RA
Y B
LOC
K38
-413
X1
425
00W
CC
9035
618
58
3SD
40
TO S
D 4
3SH
SPR
AY
CO
NTR
OL
38-4
1238
425
00W
CC
3035
618
58
4SD
44
RH C
OM
MO
N L
INE
SPRA
Y BL
OC
K38
-412
X1
315
00W
CC
7517
618
52
5SD
45
TO S
D 4
8R
H B
RA
NC
H L
INE
BLO
CK
38-4
12X
12
.515
00W
CC
4017
618
58
6SD
49
TO S
D 5
2R
H S
PRA
Y C
ON
TRO
L38
-412
312
.515
00W
CC
817
618
58
7SD
55
100%
PN
EUM
ATI
C S
OO
T BL
OW
ER S
TEA
M P
R. R
EDU
CIN
G V
ALV
E38
-411
343
2500
WC
930
198
483
2
8SD
56
100%
MO
TOR
ISED
SBP
RV
90-4
1134
325
00W
C9
3019
848
32
9SD
57
40%
PN
EUM
ATI
C S
OO
T BL
OW
ER S
TEA
M P
R. R
EDU
CIN
G V
ALV
E38
-411
142
2500
WC
912
198
483
2
HE
ATE
R D
RA
IN &
CO
ND
EN
SA
TE
SYSTE
M V
ALV
ES
Pro
ject
: N
TP
C R
ihan
d T
PS
2x5
00
MW
ST
PP
(Un
it 3
&4
)C
ust
om
er:B
HEL
Del
hi
No.
Tag
Serv
ice
Mo
del
Size
Rat
ing
*B
od
yC
vPr
.Te
mp
.Q
ty.
1A
SV 8
D/A
PEG
GIN
G F
RO
M A
UX
. ST
M.
HEA
DER
37-4
1914
1030
0W
CC
300
2024
02
2C
RH
V 6
D/A
PEG
GIN
G F
RO
M C
RH
LIN
E38
-419
1212
600
WC
972
554
360
2
3C
DV
22
& 2
5M
AIN
CO
ND
ENSA
TE C
ON
TRO
L38
-416
3114
"30
0W
CC
1600
3955
4
4C
DV
10,
12,
14
CEP
. A
,B,C
MIN
IMU
M F
LOW
REC
IRC
ULA
TIO
N37
-780
036
300
WC
611
039
556
5C
DV
43
EXC
ESS
DU
MP
CO
NTR
OL
37-7
8003
630
0W
C6
110
3955
2
6C
DV
39
GSC
MIN
IMU
M F
LOW
REC
IRC
ULA
TIO
N37
-781
036
300
WC
670
3955
2
7C
DV
67
CO
ND
ENSA
TE F
OR
SD
FLA
SH T
AN
K37
-411
X2
130
0W
C6
3.8
3955
2
8C
DV
72
CO
ND
ENSA
TE F
OR
VA
LVE
GLA
ND
SEA
LIN
G37
-411
211
300
WC
62
.539
552
9D
RV
2H
P-6A
NO
RM
AL
DR
AIN
TO
HPH
-5A
38-4
1611
360
0W
C6
3054
220
2
A P P L I C A T I O N H A N D B O O K
43
* A
NSI
4.5 Typical applications. 500 MW
Cap
acity
500
MW
HE
ATE
R D
RA
IN &
CO
ND
EN
SA
TE
SYSTE
M V
ALV
ES
Pro
ject
: N
TP
C R
ihan
d T
PS
2x5
00
MW
ST
PP
(Un
it 3
&4
)C
ust
om
er:B
HEL
Del
hi
No.
Tag
Serv
ice
Mo
del
Size
Rat
ing
*B
od
yC
vPr
.Te
mp
.Q
ty.
10D
RV 8
HP-
6B N
OR
MA
L D
RA
IN T
O H
PH-5
B38
-416
113
600
WC
630
5422
02
11D
RV 5
HP-
6A A
LT D
RA
IN T
O H
P D
RA
IN F
/T37
-412
134
600
WC
995
5428
02
12D
RV
11
HP-
6B A
LT D
RA
IN T
O H
P D
RA
IN F
/T37
-412
134
600
WC
995
5428
02
13D
RV
15
HP-
5A N
OR
MA
L D
RA
IN T
O D
EAER
ATO
R38
-416
114
300
WC
695
2218
021
14D
RV
22
HP-
5B N
OR
MA
L D
RA
IN T
O D
EAER
ATO
R38
-416
114
300
WC
695
2218
02
15D
RV
18
HP-
5A A
LT D
RA
IN T
O H
PD F
/T37
-412
136
300
WC
921
022
225
2
16D
RV
25
HP-
5B A
LT D
RA
IN T
O H
PD F
/T37
-412
136
300
WC
921
022
225
2
17D
RV
28
LPH
-3 N
OR
MA
L D
RA
IN T
O L
PH-2
38-4
1612
330
0W
C6
957
120
2
18D
RV
31
LPH
-3 A
LT D
RA
IN T
O L
P D
RA
IN F
/T37
-413
114
300
WC
920
57
140
2
19D
RV
34
LPH
-2 N
OR
MA
L D
RA
IN T
O L
PH-1
38-4
1611
630
0W
C6
300
775
2
20D
RV
37
LPH
-2 A
LT D
RA
IN T
O L
P D
RA
IN F
/T37
-413
116
300
WC
940
07
115
2
21D
RV
48
DEA
ERA
TOR
OV
ERFL
OW
TO
LP
DR
AIN
F/T
37-4
13X
16
300
WC
916
011
175
2
22D
MV
38
DM
NO
RM
AL
MU
TO
HO
TWEL
L37
-412
333
300
CF8
M95
1050
2
23D
MV
63
DM
EM
ERG
ENC
Y M
U T
O H
OTW
ELL
38-4
1233
830
0C
F8M
255
1050
2
24D
MC
W 8
3EC
W S
YST
EM F
OR
BO
ILER
AU
X.
37-4
1631
630
0C
F8M
360
1060
2
25D
MC
W 6
7EC
W S
YST
EM38
-416
3112
300
CF8
M12
6010
602
SC
AP
H C
ON
TRO
L V
ALV
ES
Pro
ject
: N
TP
C R
ihan
d T
PS
2x5
00
MW
ST
PP
(Un
it 3
&4
)C
ust
om
er:B
HEL
Ch
enn
ai
No.
Tag
Serv
ice
Mo
del
Size
Rat
ing
*B
od
yC
vPr
.Te
mp
.Q
ty.
1AS
SV10
2,10
3,14
2&14
3A
UX
. ST
EAM
TO
SEC
ON
DA
RY
SC
APH
A&
B37
-419
216
300
WC
C36
020
260
8
2A
SSV
7,
8, 4
7 &
48
AU
X.
STEA
M T
O P
RIM
AR
Y S
CA
PH A
&B
37-4
1631
430
0W
CC
190
2026
08
3A
SSV
219
& 2
20PR
IMA
RY S
CA
PH D
RA
IN T
O L
P FL
ASH
TA
NK
38-4
1621
330
0W
C6
903
.520
04
4A
SSV
204
& 2
05SE
CO
ND
AR
Y S
CA
PH D
RA
IN T
O L
P FL
ASH
TA
NK
38-4
1621
330
0W
C6
140
3.5
200
4
5BD
06,
06A
CBD
LEV
EL C
ON
TRO
L38
-416
213
300
WC
614
010
200
4
Material selection GuidelinesStandardised Materials for high performance
Temp. 150#ANSI 300#ANSI 600#ANSI 900#ANSI 1500#ANSI 2500#ANSI
< 93ºC 18.3 52.7 105.5 158.2 263.7 439.4
149ºC 16.2 51.3 102.3 153.6 255.9 426.8
204ºC 14.1 49.6 99.1 148.7 248.2 413.4
260ºC 12.0 46.8 93.5 140.3 233.8 389.5
316ºC 9.8 42.5 85.1 127.6 212.7 354.4
371ºC 7.7 40.1 79.8 119.9 199.7 332.6
427ºC 5.6 35.9 71.4 107.2 178.6 297.4
482ºC 3.5 31.6 63.3 94.9 157.8 263.3
538ºC 1.4 25.7 51.0 76.6 128.0 213.0
593ºC 0.0 22.9 45.3 67.8 113.2 188.8
PRESSURE RATING. CEILING VALUES *
MATERIAL SELECTION
* Max.. Working Pressure in Kg/cm2 for ANSI 150# to ANSI 2500#, Extracted from ANSI B16.34 - 1996. Varies
with material, See pages 48-50 for max. allowable working pressures for WCC, WC6 & WC9, the most
common body material used for Control Valves in power plant applications.
CONTROL VALVE. PRESSURE CONTAINING MATERIAL
General Classification Castings Forgings Max. Operating Temp.
Carbon Steel ASTM A 216 Gr. WCB / WCC ASTM A 105 427ºC
Alloy Steel, 1 ¼ Cr - ½ Mo ASTM A 217 Gr. WC6 ASTM A 182 Gr. F11 566ºC
Alloy Steel, 2 ¼ Cr - 1 Mo ASTM A 217 Gr. WC9 ASTM A 182 Gr. F22 566ºC
Alloy Steel, 5 Cr - ½ Mo ASTM A 217 Gr. C5 ASTM A 182 Gr. F5a 566ºC
Stainless Steel, Ty. 316 ASTM A 351 Gr. CF8M ASTM A 182 Gr. F316 566ºC
5.1 Body material specs
Correct material selection is extremely important to ensure
proper functioning and longevity of Control Valves in Power
Plant applications. The service conditions vary widely in
pressure and temperatures, design pressure can go up as high
as 360 kg/cm2 and temperatures upto 566oC. The Body and
Trim material selection should also take into account the
detrimental effects of Cavitation / Flashing / High Velocity
which are inherent to such severe applications.
A P P L I C A T I O N H A N D B O O K
47
Allowable working pressure for ASTM A 216 Gr. WCCA
llowable w
orking pressure (Kg/cm
2)
Operating temperature (oC)
5.2
Allo
wab
le w
orki
ng p
ress
ure
48
C O N T R O L V A L V E S F O R P O W E R P L A N T S
Allow
able working pressure (K
g/cm2)
Operating temperature (oC)
5.2 Allow
able working pressure
Allowable working pressure for ASTM A 217 Gr. WC6
A P P L I C A T I O N H A N D B O O K
49
50
C O N T R O L V A L V E S F O R P O W E R P L A N T S
Allow
able working pressure (K
g/cm2)
Operating temperature (oC)
5.2
Allo
wab
le w
orki
ng p
ress
ure
Allowable working pressure for ASTM A 217 Gr. WC9
A P P L I C A T I O N H A N D B O O K
51
5.3 Trim m
aterial selection
GEN
ER
AL C
LA
SSIF
ICA
TIO
NA
STM
CO
DE
MA
X. T
EM
P.H
AR
DN
ESS
GE
NE
RA
L A
PP
LIC
ATI
ON
GEN
ERA
L S
ERV
ICE
SS 3
16
Bar S
tock
: AST
M A
479
Ty. 3
1659
3ºC
14 H
RC
max
.N
on-E
rosi
ve, C
orro
sive
,Mod
. Pre
ss. D
rop.
Cas
ting
s: A
STM
A 3
51 G
r. C
F8M
Mos
t cor
rosi
on re
sist
ant o
f 300
Ser
ies
TOU
GH
SER
VIC
E
Ty.
41
0 S
tain
less
Ste
elBa
r Sto
ck: A
STM
A 4
79 T
y. 4
1040
0ºC
35 H
RC
min
.Er
osiv
e &
Non
- C
orro
sive
Ser
vice
(Har
dene
d &
Tem
pere
d)
Ty.
41
6 S
tain
less
Ste
elBa
r Sto
ck: A
STM
A 5
82 T
y. 4
1640
0ºC
31-3
8 H
RC
Eros
ive
& N
on-
Cor
rosi
ve S
ervi
ce(H
arde
ned
& T
empe
red)
No.
6 St
ellit
e H
ard
Faci
ngN
A65
0ºC
38-4
7 H
RC
Slig
htly
Ero
sive
& C
orro
sive
Ser
vice
No.
6 St
ellit
e So
lid (<
2”)
NA
650º
C38
-47
HR
CEr
osi
ve &
Co
rro
sive
Ser
vice
No.
5 C
olm
onoy
Har
d Fa
cing
NA
650º
C45
-50
HR
CEr
osi
ve &
Co
rro
sive
Ser
vice
.C
orro
sion
resi
stan
ce s
imila
r to
Inco
nel
No.
6 C
olm
onoy
Har
d Fa
cing
NA
650º
C56
-62
HR
CEr
osi
ve &
Co
rro
sive
Ser
vice
.C
orro
sion
resi
stan
ce s
imila
r to
Inco
nel
17
.4 P
H S
tain
less
Ste
el B
ar S
tock
: AST
M A
564
Gr.
630
400º
C40
HR
C m
in (H
900)
Ero
sive
& C
orr
osi
ve S
ervi
ceC
asti
ngs:
AST
M A
747
CB7
CU
132
HR
C m
in (H
1075
)
CA
6NM
Sta
inle
ss S
teel
Cas
ting
: AST
M A
743
Gr.
CA
6NM
650º
C28
HR
C m
in.
Ero
sive
& C
orr
osi
ve S
ervi
ce.
(Hea
t Tre
ated
)(7
00-1
000
HV
Aft
er c
ase
hard
enin
g, e
xcel
lent
for h
igh
afte
r Nitr
idin
g)te
mp
erat
ure
ser
vice
.
Ty. 4
40
C S
tain
less
Ste
elBa
r Sto
ck: A
STM
A27
6 Ty
.440
C40
0ºC
58 H
RC
min
.V
ery
Ero
sive
Ser
vice
.
Handling and InstallationA list of safe practices
Fig. 24. Clearance requirements for Globe Control Valves
1. Do not lift large size valvesby the Actuator. Lifting Lugsprovided on the Actuators arefor lifting the Actuator alone.
2.The Actuator Diaphragmcase, Eye Bolts etc. are notdesigned to lift the heavyvalve body assembly.
3. Do not turn the Actuator,keeping the coupling tight.
4. In case of Bellow SealedValves, never rotate theValve stem.
5. Valves on smaller pipingand tubing may need to bemounted in Brackets.
6. While choosing thelocation to mount the valve,provide adequate space forfuture occasions when it maybecome necessary to removethe Body and Actuatorfor repairs.
7. Ensure that recommendedmounting orientations arealways followed.
8. Ensure that the FlangeBolts or Tie Rods can beremoved easily.
9. Leave adequate space foropening/adjusting Positionersand Accessories.
6.1 Handling &
InstallationA P P L I C A T I O N H A N D B O O K
55
Fig. 25. Alternate orientations for Control Valves (position-1 is preferred)
10.Positioner Gauges andTravel Indicators must alwaysremain clearly visible.
11.Careful choice of locationhelps to prevent Cavitation.When flow is upward, and ifthe fluid partially vaporizesbecause of lower hydrostatichead, locating the Valvetowards the lowest part of thepiping can prevent two phaseflow through the Valvethereby minimizingCavitation.
12. Valves in Flashing serviceare to be located as close tothe receiving vessel aspossible. A very short lengthof Discharge Pipe, and anIsolation Valve are permitted.
13.Special attention must begiven not to place an elbowor pipeT less than 5 pipediameters downstream of avalve to avoid interferencewith the Valve’s FlowCapacity. In high pressure gasor steam pressure reducingapplications, try to have onlystraight pipes downstream ofthe valve, or alternatively usea long sweeping elbow toavoid added pipe noise.
14. In critical applications,provide a manually operatedthrottling valve in a bypassaround the valve. This allowsfor replacement or repair ofthe Control Valve withoutshutting down the process.
6.1H
andl
ing
& In
stal
latio
n
56
C O N T R O L V A L V E S F O R P O W E R P L A N T S
Fig. 26. Typical satisfactory arrangement of upstream and downstream piping
Fig. 27. Less satisfactory arrangement of upstream and downstream piping
15. Since Control Valves will require maintenance from timeto time, Block Valves at Upstream and Downstream areessential. Bleed and drain valves may be necessary for safety.
16.On occassions when the Control Valve is out of service, if aBypass Valve is being provided along with isolation valves inorder to have flow, the style of the Bypass Valve should besimilar to that of the Control Valve. Or else an identical ControlValve should be chosen as the Bypass Valve.
17. In cases of extreme ambient temperatures (over 80ºC)where a valve is located, the valve and accessorymanufacturers should be consulted for proper, hightemperature replacement material.
6.1 Handling &
InstallationA P P L I C A T I O N H A N D B O O K
57
Maintenance GuidelinesHow to ensure peak performance of
Control Valves in power plant applications
B E F O R E S TA R T- U P
7.1 Preventive maintenance
1. It should be appreciatedthat during plant start ups,abnormal operatingconditions can adverselyaffect the performance of theControl Valve and some timesseverely damage the valve.It is very important that theseabnormal conditions berecognized and the ControlValve is selected taking intoaccount these conditions.
2.Ensure that misalignmentalong the pipe line is notcorrected using the valve.Pipeline stress on the valvemay cause misalignment ofthe stem or plug/seat joint. Itcan also cause flange leak orpacking leak.
1. PREVENTIVE MAINTENANCE
3.Ensure that therecommended mountingorientation is followed. If avalve is mounted with it’sstem travelling in thehorizontal plane, it must beproperly supported.
4.Ensure that the mandatory‘flow through’ directionindicated on the ControlValve (by an arrow mark) isalways followed.
5.Piping should be flushedbefore installing the valve. Ifadditional flushing is doneafter installation, it may benecessary to remove theinternals, Especially if anti-Cavitation or low noise Trim isin place.
Continued in next page
A F T E R S TA R T- U P
1.Periodic field inspectionsshould be made.
2.Remember that high-friction packing needs to becompressed after insertion.Packing will compress furtherin service, and the packingcompression may have to bereadjusted. Tighten thepacking nuts when foundnecessary.
3. If dusty or dirty conditionsprevail, provide a rubber bootaround the stem to protect thepacking.
4.Cover the valve suitablywhen process dripping orcorrosive atmosphericconditions prevail. Special careto be given to the valveaccessories.
5.Air sets usually have filtersthat can clog; the drain cockshould be opened from time totime to be sure trapped liquid isdrained.
6.Monitor the performanceof the valve accessories as ithas a significant effect on thevalve performance.
A P P L I C A T I O N H A N D B O O K
61
7.2
Shop
ove
rhau
l
1. Valves and valve internalin hazardous service shouldbe cleaned thoroughly beforeundertaking any repair.Depending on contaminant,water wash, steaming orspecial heat treatment maybe resorted to.
2.Ensure that the person whois disassembling the ControlValve is thorough with therelevent procedure.
3. Before disassembly, markthe Actuator orientation withrespect to the body flanges.
6. If line trash like weld chips,rust etc. are expected in thepipeline, temporary strainersshould be installed upstream.If the process stream normallycontains Scale, dirt or otherforeign material, it isrecommended thatpermanent strainers or filtersbe installed. Strainers shouldbe installed far enough toallow non-swirl flow at thevalve inlet. Note thatstrainers that efficientlyprotect the pump may not beadequate when it comes toremoving debris that candamage the valve Trim.
7.Ensure that the air supply isclean and devoid of oil.
2. SHOP OVERHAUL
4.Remove the bonnet fromthe body, and then the glandpacking components. Furtherremove the Trim and thebottom flange.
5.Disassemble the Actuatorand examine components fordamage. Afterwards cleanthe parts carefully.
6. Inspect the disassembledcomponents thoroughly anddetermine the extent ofreconditioning and repair thatis required.
Continued in facing page
8. Air lines to be connected tothe Control Valves should beblown clean of oil and debrisbefore they are attached.
9.Avoid using Teflon® tapesin instrument air lines. WhileTeflon® tape is an excellentthread lubricant and seal forscrewed connections, itnevertheless can break off insmall bits if not carefullyapplied. And these bits oftenmigrate to orifices inpneumatic accessories andcan clog them.
10.Do not start up a ControlValve without first checkingthe packing tightness.
Maintenance. Before startup CONTINUED FROM PREVIOUS PAGE
62
C O N T R O L V A L V E S F O R P O W E R P L A N T S
7.2 Shop overhaul
7. If the body is rusted,descale the body. Whilehandling the body, the flangesurfaces must be protected toprevent any gasket leakage.
8. Assess the need forremachining of Body andTrims. First the plug and seatshould be perfectly matched,by precise machining, then byhand grinding or lapping.Make sure that even finetraces of lapping compound iscleaned off.
9.The lapped contact shouldnot be too wide. If the contactband is too wide, a machinecut to renew the angles of themating pieces is necessary.The angles of the matingpieces are slightly different toallow a narrow seating band.
10. For problems like marredstem surface, replacementwith a factory finished stem isthe only practical solution.The finish of the Control Valvestem is so fine that highlypolished surfaces are requiredto give the best possiblepacking seal, and to minimizethe hysteresis.
11. If the Trims are beyondrepair, replace them withgenuine spare parts. ValveTrims are amongst the mostprecision of instrumentationcomponents.
12.Avoid use of nonstandard Trims. These cannotmatch the metallurgy andworkmanship of factoryfinished spares.
13. Reassemble the valvebody using the reconditioned/new parts. Ensure that glandpacking and gaskets arechanged every time the valveis opened and reassembled.Use only OEM* glandpacking and gaskets. Lowquality gaskets can causeirreversible damage to thevalve by seat area Erosion,body bonnet Erosion etc.
14.While tightening thebonnet and bottom flanges, itis important to tighten thediagonally opposite bolts toensure even gasket loading.Over tightening can causeexcessive elongation of thegaskets thereby resulting inpoor joints.
15.Assemble parts of theActuator barrel, install thediaphragm case using newcap screws and nuts, andcheck for pneumatic leaks.
16.Adjust the spring rangeand stroke of the Actuator.
17.Giving air supply to theActuator, keep the Actuatorin mid stroke and mount theActuator on the valve body.
Shop Overhaul CONTINUED FROM PREVIOUS PAGE
*Original Equipment Manufacturer
A P P L I C A T I O N H A N D B O O K
63
64
C O N T R O L V A L V E S F O R P O W E R P L A N T S
20.Tubing connections forsignal and operating airshould be checked with soapywater or other leak detectingfluids.
21.Carry out hydrotest, seatleakage test and calibrationas per relevant standards.
22.When repair to anexisting valve isuneconomical, replace it witha new valve from a high-quality OEM to avail of bettersizing, better materials, betterdesign, and most likely, betterservice too. Processconditions should bestabilized and determinedaccurately in case they werenot correctly anticipatedwhen the original valvewas specified.
23. Do not buy valves orreplacement parts fromnon OEMs. Overemphasison short-term cost savingscan sometimes lead tohazardous workingenvironments for personnel,process downtime andincreased operating costs.
7.2
Shop
ove
rhau
l
18.Tighten (finger tight) thecoupling. Apply air or removeair to ensure proper seating ofthe valve. Then tighten thecoupling and adjust the travelindicator.
19. Mount the accessoriesback on to the Control Valve.Several of the most commonaccessories (Air Sets,Positioners, Transducers etc.)have Rubber Diaphragmsthat will harden and crack.Some have O Rings thatdeteriorate. It would beeconomical to replace thewhole accessory with spares(and repair faulty modelsduring slack time) rather thanrepairing them On Site. In thiscontext, it may also be notedthat accessories like SmartValve Positioners are highlysensitive to the quality ofInstrument Air. GenerallyManufacturers recommendInstrument Air to be free ofoil, water and dust to DIN/ISO 8573-1, Pollution and oilcontents according to Class 3and Dew point 10 K belowoperating temperature.
Shop Overhaul CONTINUED FROM PREVIOUS PAGE
The MIL RangeHigh performance Control Valves for power plants
8.1 MIL 21000 Series
For severe service, specialdouble stage valves withsimultaneous throttling in theplug and Cage also is available.
Tight Shut-Off: Class IV leakageis standard. Optionalconstructions meet Class V &Class VI leakage.
Quick Change Trim. Optionalclamped seat ring facilitates easyTrim removal.
Angle Body (70000 Series).Optional angle body designwith Venturi seat is ideally suitedfor special applications likeFlashing liquids and otherchoked flow conditions.
F E A F E A F E A F E A F E AT U R E ST U R E ST U R E ST U R E ST U R E S
Heavy Top Guiding. The Valveplug shank is Guided within thelower portion of the bonnet andthis heavy and rugged guidingensures plug stability andeliminates Trim vibration.
AntiCavitation/Low Noise Trimsreplacing conventional plugwith the Lo-dB plug providesexcellent noise attenuation andCavitation control.
Available Sizes & Rating
½” to 2”: ANSI 150# to ANSI 2500#
3” to 1 0”: ANSI 150# to ANSI 600#
Seat leakage class as per ANSI/FCI 70.2
Standard: Class IV.
Optional: ClassV & ClassVI
MIL 21000Rugged, heavy top Guided, singleseated Control Valves
67
A P P L I C A T I O N H A N D B O O KA P P L I C A T I O N H A N D B O O K
C O N T R O L V A L V E S F O R P O W E R P L A N T S
Available Sizes & Rating
¾” to 14”: ANSI 1 50# to ANSI 2500#
16” to 20”: ANSI 150# to ANSI 600#
Seat Leakage Class as per ANSI/FCI 70.2
Standard: Class III & Class IV
Optional: Class V
8.2
MIL
410
00 S
erie
s
MIL 41000Heavy Duty Cage GuidedControl Valves.
F E AT U R E S
High allowable pressure drops.Cage Guided valves provideexceptional performance over awide range of pressure drops insevere services. They also handlemost shut off pressures withstandard pneumatic springdiaphragm Actuators.
High capacity with low pressurerecovery. Flow capacities remainat top levels, and are attainedwith minimum pressure recoveryreducing the possibility ofCavitation in liquid service.
Standardised high performancematerial. This ensures troublefree operation even inapplications with inherent highpressure drops and extremetemperatures.
Tight shut off valves. For lowersizes, unbalanced design resultsin Class V leakage.
For higher sizes, the exceptionalsingle seated leak tightness ofClass V is achieved by thefollowing special options:
1. Auxiliary shut-off pilot plugcloses the balancing holeslocated in the main plug in shut-off conditions.
2. Self energised seal ringspressing against walls of theCage & Plug arrests leakage pastthe seal ring.
Lo-dB/Anti-Cavitation Cages:Noise attenuation andCavitation control achieved byreplacing conventional Cageswith Lo-dB Cages.
S P E C I A L O P T I O N S
Static Seal Ring, Double Cage design,Two stage design with diffuser seatring, Multi-Stage Valves
MIL 41008 . These Multi-Stage valvesincorporate a unique Trim design toabsorb high pressure drops thatprevent Cavitation and maintainconstant velocity throughout thepressure dropping stages.Concentric Cages incorporate atortuous flow path, which causesnumerous velocity head losses withoutappreciable pressure recovery. Highpressure recovery factors at lower liftseliminates Cavitation. High impedanceflow path reduces pressure by frictionand turbulence, maintaining constantvelocity throughout.
68
A P P L I C A T I O N H A N D B O O K
C O N T R O L V A L V E S F O R P O W E R P L A N T S
Available Sizes & Rating
½” to 6”: ANSI 900# to ANSI 2500#
Seat leakage Class as per ANSI/FCI 70.2
Standard: ClassV
Optional: Class VI
or High Noise Levels commonlyassociated with conventionallydesigned Control Valves.
High allowable pressure drops.No individual stage is exposedto the full pressure drop, thusextending Trim life substantially.
Adiabatic Flow with Friction.Reduces pressure much in thesame way as pressure lossoccurring in a long pipeline.
Low pressure recovery. Thisminimises Cavitation potentialand contributes towardsreduction of Noise for all fluids.Pressure recovery factors as highas 0.998.
Standardised high performancematerial:To ensure materialintegrity, 78000 Series valves aremachined from solid steelforging. High performance Trimmaterial ensures durability inany severe application.
Balanced Trims: Available forsizes 2" and above, allow muchhigher shut-off pressures withconventional Actuators.
S P E C I A L O P T I O N S
Soft seat construction withencapsulated inserts, Angle & Inlinebody configurations.
8.3 MIL 78000 Series
F E AT U R E S
Multi Step Axial Flow HighResistance Trim. Pressurereduction occurs along thelength of the plug in a series ofthrottling stages. The fluid alsotakes a tortuous flow path,which adds resistance andtherefore velocity head loss.
The special design providescontrol of high pressure fluidswithout the Erosion, Vibration
MIL 78000Anti Cavitation &Low NoiseMulti-step High Pressure DropControl Valves
69
A P P L I C A T I O N H A N D B O O K
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8.4
MIL
910
00 S
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MATRIX Series valvesMIL 91000Extreme Pressure Multi-stage,Multi-path, Axial Flow Anti-Cavitation High Pressure DropControl Valves
F E AT U R E S
Varying and expanding flowpassage. This enables near ZeroPressure Recovery thus ensuringthat stage wise Pressure Dropsare limited below the CriticalPressure Drop. Likelihood ofCavitation is ruled out even inextreme conditions.
Ingenious Flow Path. Reducesdownstream Velocity. ExitVelocity and Kinetic Energy keptunder limits. Erosion eliminated.
Pressure recovery factor (Cf) ashigh as 0.9999.
As many as 50 PressureDropping stages.
Ruggedness of design. Ensureslongevity even in the severest ofapplications.
Axial Flow design. Eliminateswire drawing effects on theleading edges of the plug.
Flow to Open flow direction.Eliminates Dynamic Instabilityinherent to Flow to Close valves.
Tortuous flow path with HighImpedance for energyabsorption limits Trim Velocity.
Modified equal % characteristicswith 100 : 1 Rangeability.Characteristics can becustomised to suit specificprocess applications.
Self energised body and seatgaskets. Ensures Zero Leak, andoptimises bonnet/bolting design.
Ingenious design. Results in asimpler manufacturing process.Consequently this makesMATRIX Series Valves betterpriced than other valves in thisleague.
S P E C I A L O P T I O N S
Available with Soft Seat with a specialsliding collar to protect the Soft Seatfrom high pressure fluids.
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8.5 Actuators
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A P P L I C A T I O N H A N D B O O K
C O N T R O L V A L V E S F O R P O W E R P L A N T S
MIL has a wide range of High Performance Pneumatic Actuatorsdesigned for all ranges of process control applications. Key Models are...
Actuators
MIL 67 / 68
MIL 57 / 58
MIL 37 / 38
MIL 37-38 Pneumatic SpringDiaphragm Actuators
Sizes : 11", 13", 15", 18" & 24"Travel : <_ 4"Supply Pressure : 20 psig to 65psig
MIL 57-58 Pneumatic Multi-Spring Diaphragm Actuators
Sizes : MS 11 & MS 13Travel : <_ 1.5"Supply Pressure : 20 psig to 45 psig
MIL 67-68 Double ActingPiston Cylinder Actuators
Sizes : 16”, 20”& 24”Travel : <_ 12"Supply Pressure : 60 psig to 100 psig
8.6
Acc
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A P P L I C A T I O N H A N D B O O K
C O N T R O L V A L V E S F O R P O W E R P L A N T S
Standard Accessories
MIL 7400 Pneumatic Positioner
MIL 496 Limit Switch
MIL 8013 Electro Pneumatic Positioner
MIL 400 Position Transmitter
MIL 7400 Positioners employ aforce balance system to ensure thatthe position of the valve plug isdirectly proportional to the controlleroutput pressure, regardless ofpacking box friction, diaphragmactuator hysteresis or off-balanceforces on the valve plug.
MIL 8013 Positioners provideprecise and reliable valve positioningand superior dynamic response, bydirectly comparing valve stemposition with controller DC outputsignal, provide dynamic responseand positioning accuracy notobtainable with transducer andpneumatic positioner combination.
MIL 496 Rotary Limit Switches(with SPDT / DPDT Microswitches orProximity sensors) are used forelectrically indicating one or twopredetermined positions in thestroke of a control valve. They maybe connected to audible alarms orsignal lights for warning of valve orsystem malfunction or used toactuate solenoids, relays and otherelectrical devices.
MIL 400 Electronic Position Trans-mitters are capable of transmittingangular movements as well as linearmovements of control valves (withproper linkages) as 4-20 mA outputsignal. MIL 400 Position Transmittersare available in following variantsMIL 400A: RVDT- Rotary VariableDifferential Transformer- operated(used for control valves havingstroke less than 3/4"). MIL 400X:
MIL also offer Profibus or Hart or Foundation Field Bus based SMARTPOSITIONERS.
Inductive Type (Used for control valves with higher stroke lengths, startingfrom 3/4") MIL 400L: LVDT- Linear Variable Differential Transformer -operated Position Transmitter.72
MIL is the first Control Valve manufacturer in India to have been awarded theprestigious CEMarking Certificate by RWTUV, Germany.
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9.0
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I N D E XAAllowable working pressure 48Accessories 72Actuators 71
BBlock Valve 24Body Material Specs 47Boiler Feed Pump Min. Recirculation Valve 13, 17, 18Boiler Feed Pump Minimum Recirculation System 17Boiler Feed Water Startup Valve 13, 17Boiler Main Feed Water Control Valve 13, 17
CCE Marking 8, 73Company overview 8Condensate Recirculation Valve 13, 14Condensate system 13, 14Condenser 14
DDeaerator 14, 15, 17Deaerator Level Control Valve 13, 14, 15, 16Deaerator Pegging Steam System 26Deaerator Pegging Steam Valve 13, 22, 26, 27
EEconomisers 17
FFeed Pump Recirculation 18Feed Water Control 20Feed Water Heaters 31Feed Water Pumps 17Feed Water Regulating System 20Feed Water Regulator Valve 20Feed Water System 13, 17Foster Wheeler 8Full Load Feed Water valve 20
GGeneral Boiler Flow Diagram 10
HHandling and Installation 53Heater Drain System 13, 31Heater Drain Valve 31High pressure heater drain Valves 13HP Heaters 31HP Heaters System 32, 55
LLow Load Feed Water valve 20Low pressure heater drain valves 13LP heaters 31LP Heaters System 32
MMain Steam Line 22Main Steam Pressure Reducing Valve 22, 29, 30Main Steam System 13, 22Maintenance Guidelines 59Martensitic Steel 15Material Selection Guidelines 45, 47MATRIX Series 8, 19, 70MIL 21000 31, 67MIL 41000 16, 21, 27, 31, 68MIL 41003 27MIL 41008 15, 21, 25MIL 41100 23, 24MIL 41114 28MIL 41121 30MIL 41128 25MIL 41200 23, 24MIL 41221 30MIL 41400 24MIL 41621 16MIL 41912 30MIL 41914 30MIL 41921 16MIL 70000 67MIL 71114 28MIL 78000 15, 18, 19, 25, 69MIL 91000 19, 70MIL Controls Limited 6, 8Modulating Type System 18
OOn/Off System 18Original Equipment Manufacturer 63
PPositioner Gauges 56PRDS Spray Control Valves 22PRDS Station Valves 29PRDS System Control Valves 22PRDS System Valves 13Pressure Reducing Desuperheating System 29Preventive Maintenance 61
RReheater Attemperator Control Valve 25Reheater Attemperator Spray Valve 13Reheater Spray Block Valves 22Reheater Spray Control Valves 22Reheater System 22Remachining 63RWTUV 73
SShop Overhaul 62Sliding Collar Seat Ring 19Soot Blower 24, 27Soot Blower Pressure Control Valves 22Soot Blower Steam Pressure Reducing Valves 13Soot Blower Valve 27Soot Blowing System 22Soot Blowing Valves 27Steam Ejectors 29Steam Soot Blowers 27Strainers 62Super Heater Attemperator Valve 22, 23Superheater Attemperator Block Valve 22, 24Superheater Attemperator Spray Valve 13Superheater Spray Control Valves 22Superheater System 22
TTeflon® tapes 62Temperature Control Valve(Spray water) 29Trim material selection 51Turbine Bypass Valves 13Typical Applications 116 MW 37Typical Applications 210 MW 39Typical Applications 250 MW 41Typical Applications 500 MW 43Typical Applications 67.5 MW 35
UUpstream Piping 57
I L L U S T R AT I O N SFig. 1. General Boiler (Drum style) Flow Diagram 10Fig. 2. Condensate System 14Fig. 3. MIL 78000 15Fig. 4. MIL 41000 16Fig. 5. Boiler Feed Pump Min.Recirculation System 17Fig. 6. MIL 78000 Feed pump Min. Recirculation valve 18Fig. 7. MIL 91000 19Fig. 8. Feed Water Regulating System 20Fig. 9. MIL 41008 Multi stage, Low Load Valve 21Fig. 10.Critical Control Valves in Main Steam Line 22Fig. 11.MIL 41100 Superheater Attemperator Valve 23Fig. 12.MIL 41200 Superheater Attemperator Valve 23Fig. 13.MIL 41400 Superheater Attemperator block 24Fig. 14.MIL 41008 Reheater Attemperator Control Valve 25Fig. 15.MIL 78000 Reheater Attemperator Control Valve 25Fig. 16.Deaerator Pegging Steam System 26Fig. 17.MIL 41003 27Fig. 18.MIL 71114 28Fig. 19.Typical Auxiliary PRDS System 29Fig. 20.MIL 41914 30Fig. 21.MIL 21000 31Fig. 22.LP Heaters System 32Fig. 23.HP Heaters System 32Fig. 24.Clearance requirements for Valves 55Fig. 25.Alternate orientations for Control Valves 56Fig. 26.Typical satisfactory piping 57Fig. 27.Less satisfactory arrangement of piping 57
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© MIL CONTROLS LIMITED, 2007. All rights reserved
Control Valves for Power Plants.Application HandbookThe MIL Power Plant Handbook providesa broad overview of the various systems ina Thermal Power Plant to help you select theright valve for each application.
The handbook also offers expert tips forproper Installation and Maintenance ofyour Control valves.
Registered Office & Works.Meladoor , Mala, PIN 680 741, Thrissur District, Kerala, India.Tel: + 91 (0)480 2890272, 2890772, 2891773.Fax: + 91 (0)480 2890952. Email: [email protected]
Marketing Head Office.Thaikkattukara P.O., Aluva, PIN 683 106, Ernakulam Dist, Kerala,India.Tel: 91 (0)484-2624955, 2624876. Fax: 91 (0)484-2623331.Email: [email protected]
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2007
MIL Controls Limited
A KSB Company