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T A B L E O F C O N T E N T S

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2

Simple Cycle Power Plant (Gas Turbine Generator) . . . . . . . . . . . . . . . . . . .4Simple Cycle Power Plant Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5

Gas Turbine ApplicationsCompressor Air Extraction Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6Air Extraction Pilot Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7Trip Oil Solenoid Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8False Start Drain Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9Optional Liquid Fuel Skid Control

Gas Purge Vent Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10Gas Purge Block Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10Liquid Fuel Stop Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11Atomizing Air Bypass Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12Fuel Nozzle Purge Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12

Generator Gas Control Valves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13Gas Turbine Selection Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Conventional Fossil Fueled Plant (Steam Turbine Generator) . . . . . . . . . .16Conventional Fossil Fueled Plant Diagram . . . . . . . . . . . . . . . . . . . . . . . . . 17Combined Cycle Power Plant (Gas & Steam Turbine Generator) . . . . . . . .18Combined Cycle Power Plant Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19

Steam Plant ApplicationsFeedwater Control Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20Boiler Feedpump Recirculation Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21Attemperator Spray Control Valves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22Gland Seal Steam Control Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24Turbine Bypass Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25Auxiliary Steam Pressure Reduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26Turbine & Header Drain Valves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28Heater Drain Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29Steam Plant Selection Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30

AppendixANSI B16.34 P&T Ratings

WCB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32WC9 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33CF8M . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34

FCI 70-2 Seat Leakage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35Velocity Recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36Noise Attenuation Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36

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A subsidiary of International, Inc. APPLICATION GUIDEINTRODUCTION

The generation of electricity is accomplished inmany different ways, base load thermal plants,nuclear powered plants, hydroelectric plants,gas turbine generators, combined cycle plants,diesel engine generators, geothermal energy,solar and wind powered plants. This appli-cation guide discusses those plants that utilizecontrol valves of the type that Leslie Controlsmanufactures; Simple Cycle Gas TurbinePlants, Combined Cycle Gas and SteamTurbine Plants, and Conventional FossilFueled Steam Turbine Plants.

Simple Cycle Plant(Gas Turbine)

Simple Cycle Combustion Turbines havebeen used for many years to generate relativelysmall amounts of electricity during peakdemand periods. These generators basicallyuse a jet engine to burn natural gas to power aturbine generator.

In the past, Simple Cycle plants wereprimarily used to generate small amounts ofelectricity for peaking power demand. Todaythese units generate up to 375 MW of elec-tricity and can be base loaded.

This method of power generation is oftenpreferred due to its clean operation, smaller siterequirement and short lead-time to license,construct and commission into operation.

Conventional Fossil Plant(Steam Turbine)

This is the most common form ofgeneration installed during the last half of the20th Century. A field-erected boiler provideshigh pressure, superheated steam to a steamturbine generator. The common fuels for theboiler are natural gas, oil or coal.

These plants have different operatingpressures and therefore efficiencies. The boileris usually a drum type field erected unit thatsupplies 900 to 2500 PSIG steam at temper-atures up to 1050ºF to the steam turbine. Ultrahigh-pressure plants or Supercritical Unitssupply steam pressures up to 3600 PSIG.Conventional fossil plants most often utilizedfor the base power requirements of the utility.

Combined Cycle Plant(Gas and Steam Turbine)

In recent years new power plant designs,combining a combustion turbine with a wasteheat recovery boiler, have proven to yield amuch higher efficiency than a simple cycle orconventional fossil-fueled plant. The commonterm used for the waste heat recovery boiler isHRSG, Heat Recovery Steam Generator. Acombined cycle plant can operate with outputsof up to 800MW, with thermal efficiencies up to60%. A conventional fossil-fueled power plantis limited to approximately 30% thermalefficiency.

This type of plant uses the exhaust gasesfrom a combustion turbine to fuel the wasteheat recovery boiler. The multi-drum boiler usesthe latent heat of the hot exhaust gas togenerate steam. The HRSG is also fired withsupplemental gas to maintain steam temper-atures required by the steam turbine. Thesteam produced by the boiler is then used todrive a steam turbine and generate additionalelectricity. The HRSG can be used inconjunction with either one, two or three steamturbines.

Much of the new generation capacity beingdeveloped worldwide today utilizes this design.

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A subsidiary of International, Inc. APPLICATION GUIDESimple Cycle Power Plant (Gas Turbine)

Simple Cycle Power Plants have beenused for many years to provide additionalgenerating capacity to a utility during peakdemand periods. Peak demand periodsgenerally occur during the summer months,when air conditioning operation consumeslarge amounts of electricity for a relatively shortperiod of time. During this time some utilities,for various reasons such as lack of capacity orunanticipated emergency shutdowns, can notmeet the demand on their system. It is thenwhen simple cycle power stations are broughton line to supply additional power rather thanhaving to purchase power on the open market.Likewise during the coldest winter months,where electric heat is the main source ofresidential home heating, peaking power isoften required from simple cycle plants. Thistype of electric generation is also popularwhere relatively small amounts of electricity areneeded at an industrial or commercial facilityand it is more economical to generate therequired power than to purchase it.

Simple Cycle plants get their name whencomparing this form of power generation to theconventional thermal fossil plant or a combinedcycle plant. A Simple Cycle Power Plant can becalled a once-through power generator. Thisplant is fueled by either natural gas or if it is adual fuel combustion turbine, natural gas and aliquid fuel. The fuel is burned in a combustion

section that converts that energy to a rotarymotion that then drives an electric generator.The hot exhaust gases from the combustionsection are discharged to atmosphere and notused for any other purpose. Thus the termsimple cycle or once-through.

Gas turbines are actually composed of anair compressor segment, a combustion seg-ment, and turbine segment. The air compressorsection takes in air and increases its pressureto approximately 225 PSI at 595ºF just prior toentering the combustion segment. At thecombustion segment, the fuel burns with theair, releasing energy to the turbine segment.The turbine rotates the shaft, providing theenergy needed for a compressor, a generator, apump, and other load. Auxiliary systems, suchas a fuel skid for dual fuel usage, support thesegments of the turbine and required actuatedvalves to control their operation.

The Simple Cycle Power Plant plays acritical role in the efficient delivery of ourelectrical requirements. These units are essen-tially jet engines attached to electric gener-ators. Thus safe, reliable control equipment isof utmost importance to its owner andoperators.

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A subsidiary of International, Inc. APPLICATION GUIDECompressor Air Extraction Valve

PurposeThe initial segment of a Combustion

Turbine is an air compressor. The aircompressor takes in air and increases itspressure just prior to entering the combustionsegment of the turbine. The Compressor AirExtraction Valve, sometimes referred to as a“bleed” valve, is critical to the operation andprotection of the combustion turbine. Thepurpose of this valve is to quickly dump thecompressed air out of the compressor when anupset condition occurs. By doing so the turbineavoids an overspeed or surge situation.

Operating ConditionsThe Compressor Air Extraction Valve is

operated by an air cylinder where the operationis air to close/spring to open thus fail open.Upon startup the valve is open and remainsopen as the turbine accelerates. When theturbine reaches approximately 95% full speed,the valve is closed and remains closed whilethe turbine is running. Immediately upon aturbine trip the valve reopens quickly to dumpthe air from the compressor portion of theturbine to slow the rotation of the shaft. Twoimportant design considerations for theextraction valves are the excessively hotenvironment and the possibility of corrosion

with time. The ambient temperature can be ashigh as 425ºF. In addition, the extraction airgoing through the valves can exceed 600ºF.Because these valves often remain closed formonths at a time while the combustion turbineis operating, there is a real likelihood thatmoisture will condense around the seat ringand result in valve body corrosion. Thiscorrosion can result in the valve disc sticking inthe seat thus greatly elevating the openingtorque requirement of the valve. For this reasonvalves without the proper material selection canbe problems waiting to happen. Should thisvalve fail to open, serious damage can be doneto the turbine.

Leslie SolutionLaurence solved these problems by

providing a butterfly valve with an all stainlesssteel valve body and an all stainless steelactuator with a single main bearing to preventbinding from heat distortion. The LaurenceCompressor Air Extraction Valve is available in6", 8" and 10" sizes, with spacers to adapt tovarious turbine configurations. The all stainless,high temperature design sets the Laurencevalve apart from standard butterfly valves andprovides years of trouble free service.

AirInlet

CombustionSection

Generator

Expander

A A

C

D

J K

B

Compressor

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A subsidiary of International, Inc. APPLICATION GUIDEAir Extraction Pilot Valve

PurposeThe purpose of the Compressor Air

Extraction Pilot Valve is to control the operationof the Compressor Air Extraction Valve. Thisvalve is de-energized when the turbine tripsthus venting the air from the extraction valveactuator and opening the extraction valve. Asolenoid pilot valve provides reliable, safeoperation of the extraction valves.

Operating ConditionsThis application requires a valve that can

reliably operate in a high temperatureenvironment, with moist, corrosive air, andprovide a high factor of safety for operating,with no minimum pressure or flow requirement.The Three-way Compressor Air Extraction PilotValve is normally closed (energized) while theturbine is running (95% full speed or greater). Inthe closed position it maintains a constant airpressure on the extraction valve actuator tokeep the valve closed. When a turbine tripoccurs the pilot valve is de-energized and theextraction valve’s actuator air is vented causingthe Compressor Air Extraction Valve to beopened by the spring force of the actuator.

Normal operating temperatures arebetween 420 and 550ºF.

Leslie SolutionLaurence provides a Three-way Rotary

Solenoid Actuated Valve with greater actuationand return reliability than conventional solenoidvalves. This is possible because of themechanical advantage achieved by using along external operating level to actuate thevalve. The external lever connects the liftingaction of the linear actuator to the valve plugthrough a rotary shaft seal. The Soli-ConElectric Actuator, provided exclusively byLaurence, is a solid-state controlled actuatorwhose circuitry delivers a direct current to thecoil regardless of the type input voltage. TheSoli-Con Actuator incorporates an internaltimer to control the inrush current; thus thecurrent is not dependent on the plungerposition. This eliminates coil burnouts due tothe valve failing to stroke. The timer automa-tically resets upon de-energization. Due to itsunique design and highly reliable Soli-ConElectric Actuator the Laurence Three-wayCompressor Air Extraction Pilot Valve hasoffered years of low cost, maintenance freeservice in this harsh environment.

Compressor

AirInlet

CombustionSection

Generator

Expander

A A

C

D

J K

B

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A subsidiary of International, Inc. APPLICATION GUIDETrip Oil Solenoid Valve

PurposeThe purpose of this valve is to dump

hydraulic oil quickly when the load is suddenlytaken off the shaft of the turbine or in a normalshutdown to prevent damaging overspeed. Thiscan take place in one to two seconds. Thehydraulic oil is the pilot operating fluid for themain gaseous fuel shutoff valve, the main liquidfuel shutoff valve, and the piston actuatoroperating the compressor inlet guide vanes.

Operating ConditionsThese valves are normally open, energized

to close with oil pressure under the seattending to open the valve. The valve is de-energized to open and dump hydraulic oil.These valves are open when the turbine isdown, or individually when that particular fuel isnot being used. They are closed when thatparticular fuel is being used. When selecting avalve for this application, particular care needs

to be taken to insure that the valve selectedcan operate reliably under conditions where theoil is susceptible to contamination and wherehigh temperature is common.

Leslie SolutionThe Laurence Two-way Rotary Valve is

particularly well suited for this application. Bydesign the Laurence poppet-type plug ispushed open by the oil pressure even if thereturn spring weakens providing an extrameasure of safety to this function. Some valvesare designed with a closely fitted springreturned cartridge plug. These valves arevulnerable to foreign matter in the oil andbinding from temperature distortion. TheLaurence Two-way Rotary Valve overcomesthese problems with a superior design concept.

Compressor

AirInlet

CombustionSection

Generator

Expander

A A

B

C

D

J K

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A subsidiary of International, Inc. APPLICATION GUIDEFalse Start Drain Valve

PurposeThis valve is intended to drain the

collective combustion cans and related pipingon the turbine of unburned fuel that may existafter a fault trip during startup. This valve isalso used to drain any condensate that mayaccumulate while the turbine in not operating.

Operating ConditionsThe False Start Drain Valve is critical to the

safe operation of a gas turbine. If this valve failsto open the result could be a flash fire thatwould seriously damage the combustionsection of the turbine. The minimum result ofnot draining the residual fuel in the turbinewould be an uneven combustion resulting in aloss of generation capacity or a turbine trip.Typically this application requires a valve that isnormally open, air-to-close, fail open. Pilot aircomes directly from the compressor discharge.When the turbine is down the valve is open.Upon startup the air pressure from thecompressor increases until it overcomes thereturn spring force at which time the valve

closes. Upon a trip or deceleration of theturbine the air pressure decreases and thespring opens the valve. Because closing andreopening occurs at very low compressordischarge pressures (4 to 10 PSI), this valvemust always remain totally free operating. Anabsolute minimum of breakaway force (friction)is necessary for the valve to respond to thevery low forces from these pressures.

Leslie SolutionLaurence’s solution to this application is a

1" Two-way Rotary Cylinder Actuated Valve.Unlike conventional solenoid actuated valves,this valve offers a metal to metal seat for tightshutoff yet is sensitive to very low differentialpressures in the actuator. The rotary seal andactuator are specifically designed with lowfriction materials to insure that the valve openswithout fail at low actuator pressures. Reliableoperation at low air pressure differentials andtight shutoff are critical to this application.

Compressor

AirInlet

CombustionSection

Generator

Expander

A A

B

CC

D

J K

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A subsidiary of International, Inc. APPLICATION GUIDEOptional Liquid Fuel Skid Control

ApplicationGAS PURGE VENT VALVE

PurposeOne of these valves is used between the

two Gas Purge System Block Valves to ventany fuel gas that leaks by the first block valve,as a safety precaution. The gas is vented eitherto atmosphere or to a flare. Failure to reopenwhen switching fuels could cause a trip of theturbine and in some cases damage.

Operating ConditionsThis valve is normally open, energized to

close, and designed to fail open. It is openwhenever the turbine is down or whenever it isrunning on gaseous fuel. It is energized closedwhenever the turbine is running on liquid fuel.This valve indirectly sees the high temperaturecompressor discharge air (up to 795ºF) at itsinlet.

Leslie SolutionLeslie Controls solution to this application

is the Laurence Two-way Rotary Soli-ConActuated Valve. This valve is well suited for thehigh temperature environment in which itoperates. The minimum shaft rotation and leverarm operation makes this valve a safe, reliablechoice for this critical application.

ApplicationGAS PURGE BLOCK VALVE

PURPOSETwo of these valves are used in series as a

double block to prevent fuel gas from passinginto the compressor of the turbine, whichobviously could lead to a disastrous explosion.They are open when the turbine is running onliquid fuel and allow compressor discharge airto pass in the opposite direction to maintain acontinuous purge of the gas nozzles to preventliquid fuel backup and choking of the nozzles.

Operating ConditionsThese valves are closed whenever the

turbine is down and whenever it is running ongaseous fuel. They are normally closed, with airto open and air to close. Normally these valvesare fail closed.

Leslie SolutionLaurence supplies a Two-way Rotary

Cylinder Actuated Globe Valve for thisapplication. They have a return spring strongenough to insure that the valve will return to thefail closed position when the turbine trips or inthe event of a pilot air or electric failure. Adouble acting cylinder actuator is used so thatthe valve can hold closed against a negativedifferential of gas pressure as a redundantsafety measure. This has proven to be aproblem with single acting diaphragm actuatorswhich are unable to hold against the negativedifferential.

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A subsidiary of International, Inc. APPLICATION GUIDEOptional Liquid Fuel Skid Control

ApplicationLIQUID FUEL STOP VALVE

PurposeThe Fuel Stop Valve is used as a safety

shutoff valve for liquid fuels. The purpose ofusing this valve is to isolate the turbine from fireand to provide a double barrier to precludeleakage and gradual buildup of unburned fuelon the turbine base. They are always installedoff base on a separate skid called the FuelForwarding Skid. In most cases this skid is inclose proximity to the turbine, but in somecases is quite distant. The valves are almostalways mounted outdoors and subject to thefull brunt of local weather conditions and tohazardous fuel vapors.

Operating ConditionsAs a safety valve this valve’s performance

is a critical component of the Gas TurbineSystem on dual fuel turbines. When the unit isoperating with natural gas fuel this valve isrequired to operate reliably and maintain a tightshutoff. Naturally when the combustion turbineis switched to liquid fuel, this valve opens andremains open during turbine operation.

Leslie SolutionFor many years the Laurence Soli-Con

Actuated Globe Valve has been used for thisapplication. The Rotary Solenoid Valve hasproven to be a reliable economic valve for thisservice. The strength and reliability of the Soli-Con Electric Actuator make it the safe choicefor liquid fuel shutoff applications.

LiquidFuel Skid

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A subsidiary of International, Inc. APPLICATION GUIDEOptional Liquid Fuel Control

ApplicationATOMIZING AIR BYPASS VALVE

PurposeThis valve is used to divert or bypass

atomizing air away from the liquid fuel nozzleon dual fuel units when the turbine is runningon gas fuel. When a dual fuel combustionturbine is operated on a liquid fuel atomizing airis needed to break up the liquid into a finespray for more efficient combustion. But whenthe turbine is being operated on gas, the liquidfuel does not need the atomizing air thus it isdiverted.

Operating ConditionsOperating off of air from the compressor

portion of the turbine, this valve is normallyclosed, air to open, fail closed by return spring.It is actuated open when firing on gas; it isclosed when the turbine is down or when firingliquid fuel.

Leslie SolutionUntil 1994 Laurence supplied a 3" Two-way

Rotary Cylinder Actuated Globe Valve for thisapplication. This valve is still offered in sparesor replacement situations.

Due to design changes, the valve of choiceon new units is a high performance butterflyvalve. Laurence now supplies both 4" and 6"wafer valves with a reinforced Teflon seat andpneumatic actuator.

ApplicationFUEL NOZZLE PURGE VALVE

PurposeThis valve is used to purge any fuel oil from

the gas nozzles while the turbine is running ona gaseous fuel. Conversely it is also used tovent any residual gas in the system once theturbine has switched over to liquid fuel. It usesatomizing air for this purpose.

Operating ConditionsThis application requires a three-way valve

that is normally closed to the fuel oil when theturbine is operation on liquid and opened tovent any residual gas in the system. When air isapplied to the actuator the valve opens topurge any fuel oil from the gas nozzles andcloses the gas fuel vent. A critical designconsideration for this valve is that it has theability to operate using high temperatureactuator air up to 425ºF.

Leslie SolutionThe Laurence solution to this application is

a Three-way Rotary Cylinder Actuated Valvewith indirect lever actuation of the valve plug.The indirect lever action on the valve plug has amechanical force advantage compared todirect acting solenoid valves. Because therotary motion that actuates this valve is soslight (20-30 degree arc) it is able to providereliable operation for a long time period withouta requirement for seal maintenance. Thecylinder actuator is also designed to providelong service life operating with air temperaturesup to 550ºF.

LiquidFuel Skid

G

I

H

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E

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A subsidiary of International, Inc.

Generator Gas Control Valves

APPLICATION GUIDE

Generator

J K

Expander

PurposeThe electric generator segment of a

combustion or steam turbine utilizes twoindustrial gases to improve efficiency andprotect the turbine from explosion or fire.Hydrogen gas is injected into the turbine tocool the turbine bearings and to give theturbine a lighter gas environment in which tooperate. By operating the generator in ahydrogen environment there is less molecularresistance created in the generator thus itoperates more efficiently. However, uncon-trolled hydrogen gas is very volatile and cancause an explosion if ignited by a spark. Forthis reason, carbon dioxide gas is supplied tothe generator to evacuate the hydrogen gasand prevent a flammable situation when theturbine trips.

Operating ConditionsThe hydrogen supply line to the generator

requires a fast acting shutoff valve to close offthe gas supply when an emergency situationarises. Upon trip of the turbine an electric

signal is sent to the shutoff valve to close andstop the flow of hydrogen to the generator. Thisvalve is equipped with a manual reset to openit when it is safe to restart the generator.

Conversely when a trip situation occurs,carbon dioxide gas is injected into thegenerator to purge the hydrogen gas out andprevent a fire or explosion. This valve alsoneeds to be a fast acting, fail safe design witha manual reset. Both valves are installed in thegenerator cab next to the generator.

Leslie SolutionLeslie supplies a Two-way Rotary Solenoid

Actuated Globe Valve for both of these appli-cations. They are FM approved explosion proofvalves for Group B applications. These valvesare provided with weld end connections toinsure the integrity of the installation. TheLaurence Two-way Rotary Globe Valve offers asafe, reliable, fast acting solution to a verycritical application where a failure to operateproperly could result in a catastrophic situation.

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A subsidiary of International, Inc. APPLICATION GUIDEGas Turbine Valve Selection Guide (GE)

GAS TURBINE APPLICATIONS VALVE TYPE FRAME SIZES 5, 6, 6F FRAME SIZES 7, 7F FRAME SIZE 9 FRAME SIZE 9F

Compressor Air Extraction Butterfly Cylinder 6" 6509/6512 8" 6515 8" 6515 10" 6519/21/22

Three-way Pilot for CAE Three-way Solenoid 3/4" 3315V788DCS-M 3/4" 3315V788DCS-M 1" 3319V1208DCS 1" 3319V1208DCS

False Start Drain Valve Two-way Cylinder 1" CYS516J42LCS 1" CYS516J42LCS 1" CYS516J42LCS 1" CYS516J42LCS

Gas Purge System Block Valve Two-way Cylinder 2" CYD506882 4" CYD610994 4" CYD610994 4" CYD610994

Gas Purge System Vent Valve Two-way Solenoid 3/4" 641SC364 1-1/2" 641SC720 1-1/2" 641SC720 1-1/2" 641SC720

Atomizing Air Bypass Valve Two-way Cylinder 3" CYS50697 3" CYS50697 3" CYS50697 3" CYS50697

Fuel Nozzle Purge Valve Three-way Cylinder 3/4" CYS3305X 3/4" CYS3305X 3/4" CYS3305X 3/4" CYS3305X

Liquid Fuel Stop Valve Two-way Solenoid 2" 629GSC860 3" 629GSC960 3" 629GSC960 4" 629GSC980

Trip Oil Solenoid Valve Two-way Solenoid 3/4" 532GE38 3/4" 532GE38 3/4" 532GE38 3/4" 532GE38

Generator Hydrogen Shutoff Valve Two-way Cylinder 1/2" 1129G14SW 1/2" 1129G14SW 1/2" 1129G14SW 1/2" 1129G14SW

Generator CO2 Supply Valve Two-way Cylinder 1" 1269G34DCSWS 1" 1269G34DCSWS 1" 1269G34DCSWS 1" 1269G34DCSWS

Generator CO2 Vent Valve Two-way Cylinder 2" 1279G69DCSW 2" 1279G69DCSW 2" 1279G69DCSW 2" 1279G69DCSW

Note: Frame Sizes Shown are General Electric Model Numbers

CONVENTIO

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A subsidiary of International, Inc. APPLICATION GUIDEConventional Fossil Fueled Plant (Steam Turbine Generator)

The generation of electric power beginswith the generation of steam. Water is pumpedunder high pressure from the boiler feedpumpto the boiler. The flow of the feedwater to theboiler is regulated by the feedwater controlvalve (1).

A special startup feedwater control valve(1A) is installed parallel with the main feedwatercontrol valve. This control valve is used duringplant startup with smaller flows and severecavitation as the boiler comes up to pressure.

Another element of the feedwater controlsystem is the feedpump recirculation controlvalve (2). The purpose of this control valve is tomaintain a minimum flow through the pump bydiverting back to the deaerator. This valveprevents damage to the feedpump that occursat low flow.

Once inside the boiler this high pressurewater is converted to steam. The steam issuperheated before it leaves the boiler, due totube surface area and fluctuating flows, thetemperature can fluctuate. The steam turbinerotates at 3600 RPM and cannot toleratetemperature swings. The attemperator(reheat/superheat) spray CV (3) regulates waterspray of the steam to control temperature. Thesuperheat section feeds the HP section of theturbine, then the steam is returned to thereheat section of the boiler for additionalenergy. Again, spray tempers the steam toreturn to the IP or LP turbine section.

Main steam headers are equipped withdrain valves (4) to remove condensate build upso that downstream equipment such as thesteam turbines are not damaged by slugs ofwater.

Often these sections have a bypass loop todivert steam from turbine to condenser oratmosphere. This is used during startup forboiler minimum flow or to avoid boiler tripduring system load rejection. A turbine bypassCV (5) controls flow through this loop. Thisbypass often requires a water control valve (6)to control the desuperheating water injectedinto the steam to cool it down.

To expel any condensate that forms inturbines, turbine drain CV's (4) are used. Theseare on-off applications with flashing. Turbinegland seal steam CV's (7) regulate steam tobearings during startup to seal air from enteringbearing area.

Steam from the low pressure turbine iscondensed in the condenser to be recirculatedback to the boiler. After undergoing chemicaltreatment, the condensate travels through aseries of feedwater heaters. Each successiveheater uses higher pressure (temperature)turbine extraction steam. The condensate inthe heater is flashed to lower pressure heaterthrough heater drain CV (9). Each feedwaterheater has an emergency level or drain valve(9), this valve dumps to condenser on run awaylevel.

Before entering the boiler feedwatersystem the water has air/oxygen removed inthe Deaerator. This also provides some heatingof the water. Makeup water from the BFPDischarge can be supplied via Deaerator LevelCV (8). During turbine trip conditions it isnecessary to provide deaeration of water, thepegging steam CV provides makeup.

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18

A subsidiary of International, Inc. APPLICATION GUIDECombined Cycle Power Plant (Gas and Steam Turbine Generator)

The Combined Cycle Power Plant hasmany advantages when compared to SimpleCycle or Conventional Fossil Fuel Fired PowerPlants. The following are some of the reasonsthat Combined Cycle Power Plants are one ofthe most popular design choices for utilitiesand independent power developers.

• Greater thermal efficiency whencompared to a Simple CyclePower Plant.60% for CC vs. 30% for SC.

• Much shorter construction cycleallows units to come on linequicker. Generate profits faster.

• Lower capital requirements thanconventional fossil fuel plant.

• Cheap, plentiful natural gas fuelavailability.

• Much lower emission output whencompared to a traditional powerplant.

• Reduced operating andmaintenance costs.

• More cost effective than simplecycle units.

• Smaller site requirements andfaster regulatory approval.

• CC units can often fit on theproperty of an existing powerplant.

A Combined Cycle Power Plant consists ofat least one gas and/or liquid fueledcombustion turbine, a heat recovery steamgenerator (HRSG) and a steam turbinegenerator. The term Combined Cycle comesfrom the fact that you are generating electricitywith both a gas turbine and a steam turbine atthe same unit. The exhaust gases from thecombustion turbine are routed to the HRSGand are used to produce high pressure steamto drive a steam turbine generator.

As mentioned above, this combinationresults in a plant with thermal efficiency in the60% range.

Increased efficiency can be achieved bysupplementary firing of the HRSG with naturalgas.

An HRSG can have one, two or threestages of steam production (low, intermediate,and high pressure) and up to three steamturbine generators.

The control valves associated with theHRSG section of the Combined Cycle aresimilar to those found on a traditional fossilfueled power plant. Steam and condensatepressures to 2700 PSI and temperatures up to1070ºF are not uncommon. Severe servicecontrol valve designs are required to meetthese conditions.

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CombinedCyclePowerPlant(GasandSteam

TurbineGenerator)

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20

A subsidiary of International, Inc. APPLICATION GUIDEFeedwater Control Valve

PurposeThe purpose of the Feedwater Control

Valve is to regulate the level of water in theboiler drum. A conventional fossil fueled plantwill have one steam drum. In a combined cycleplant there can be up to three drumsdepending on the HRSG design. A lowpressure, intermediate pressure, and highpressure drum are not uncommon. This controlvalve receives water flow from a constantspeed pump and supplies water to the drum tomake up for that used to produce steam.Typically the control system measures drumlevel, uses feedwater flow to compensate forerrors and steam flow as a feedforward toanticipate changes in level. This design iscalled three element control, during startup thecontrol uses drum level only (single element).

Operating ConditionsThe main Feedwater Control Valve is a high

pressure, low differential application. Thisapplication usually requires a cage guidedcontrol valve for control characteristics andeconomy of actuator size. During startup andshutdown this application can see highpressure and differential, requiring cavitationtrim to prevent damage. Usually a startup

feedwater valve is installed parallel to mainfeedwater valve with cavitation trim.

The most common problem is selection ofproper body and trim for the conditions. Manytimes body velocities can exceed 30 feet persecond. Carbon steel bodies will erode overtime, C9 is the choice when velocities exceedthese levels on a continuous bases.

Leslie SolutionThe high pressure and low differential

pressure makes this application ideal forAeroflow cage guided balanced plug controlvalve. The balanced plug allows for stablecontrol and economic actuator selection.Aeroflow’s standard custom cage gives Lesliethe ability to match capacity with the applica-tion requirements. Normally this valve does notrequire a tight shutoff.

In situations where the pump dischargepressure is less than 2500 psi, the C3 cageoption affords the customer one valve to handlestartup and main feedwater control. The cavi-tation trim exists for the first 40% travel, thecontrol system limits travel to 40% until drumpressure is sufficient to stop cavitation.

Boiler

FeedwaterHeater

FT

FC

Feedwater RegulatorValve

Boiler FeedPump

21

A subsidiary of International, Inc. APPLICATION GUIDEBoiler Feedpump Recirculation Valve

PurposeThe function of a boiler feedpump

recirculation valve is to insure that adequateflow is maintained through the boiler feedpumpto prevent overheating of the pump andcavitation. The pump manufacturer calculatesthe minimum flow required to prevent the riskof premature pump failure due to bearingsoverheating and seizure or excessive thermalexpansion of impeller blades.

A minimum flow through the boilerfeedpump also protects against erosion andinstability caused by cavitation at low flowconditions. Because the highest pressure in apower plant is produced at the boiler feedpumpdischarge, this equipment has the highestdamage potential.

Operating ConditionsThe Boiler Feedpump Recirculation Valve

protects the pump during boiler startup andshutdown. Recirculation flow either goes to thedeaerator (fossil units) or the condenser(nuclear units). Discharge pressures aretypically 10 to 20 percent above the boiler’sdesign pressure. Since most fossil unitsoperate between 1,500 and 3,600 psi,feedpump discharge operates between about1,750 and 4,400 psi at 350 to 400ºF.

Due to valve design limitations, thesevalves are generally either open or closed. Thesystem monitors flow and fully opens the valvewhen flow is below a minimum value, typicallybetween 25 and 35 percent. As long as thepump is operating above the recommendedminimum flow, the valve is closed against thehighest pressure in the plant. The combinationof head pressure and deaerator operation canproduce a back pressure on the valve of 50 to250 psi. The typical valve specified for boilerfeed water recirculation is an ANSI Class Vshutoff valve with metal to metal seat.

Leslie SolutionThe optimum valve for this application

offers zero leakage at the rated pressuredifferential. The Leslie Aeroflow Valve offersClass 8, ZERO leakage, regardless of pressuredrop or size. The Aeroflow Valve utilizes a TriShear plug design that protects the seat fromwire drawing and erosion damage, to insureZERO leakage performance for an extendedperiod of time. Les-Cav Trim is normally used,with up to five stages of pressure reduction toprevent damage due to cavitation. This isnormally a carbon steel valve, 900 to 2500ANSI Class. Some applications due to highbody velocity and erosion concerns require aC9 or CF8M body material.

BoilerFeedpump

Pump Discharge1000-4400 psig

Deaerator50-350 psig

22

A subsidiary of International, Inc. APPLICATION GUIDEAttemperator Spray Control Valves

PurposeThe Superheat, Reheat or Attemperator

Spray Control Valve is used for controllingsteam temperature to the turbine. The turbine isrotating at 3600 RPM and requires constanttemperature to prevent damage. Thisapplication provides control of temperature thatvaries with flow, constant surface area, burnertilts and varying heat release of fuels. Thecontrol of optimum temperature maintainsoptimum turbine efficiency.

Turbines are designed with a maximum(trip) temperature in mind (usually 1100°F).Above this temperature turbine damage due tomaterial constraints and clearance would result.As the trip temperature is approachedmaximum turbine efficiency is achieved. Thepurpose of the spray control valve is tomaintain a tight temperature band which resultsin maximum turbine efficiency (usually 1005-1050°F).

Today all utilities are seeking the best heatrate or efficiency. With the improvements ofmeasurement of temperature and accuracy ofcontrol systems, the weakest link is the spraycontrol valve.

Operating ConditionsThe supply water for the spray valves

usually comes from the Feedpump discharge.The outlet pressure is equal to the superheateror reheat pressure plus nozzle back pressure.The superheat spray valve sees a low DP,usually 200 to 300 psi. Turndown and accuracyof positioning is of key concern. The reheat

spray valve is normally a high DP, withcavitation and seat leakage a major concern.

The major problem exists with reheatspray. High DP causes excessive seat leakageand the valve normally operates close to theseat. Seat leakage, wire draw and inaccuratecontrol causes a reduction in steam tempera-ture and efficiency.

Leslie SolutionThis application is ideal for Leslie's T2

High Gain Trim. The accurate and fastpositioning provides for a very tight band oftemperature. The internal pilot allows stemsizes of 3/8" to 1/2" minimizing stem sealconcerns. The custom cage for Reheat Sprayallows for proper stroke versus flow and tightcontrol. The Mini-P Trim is used for low flowcontrol with cavitation protection to 2000 psid.

The DPS (digital positioning system)utilizing optical position feedback for .00125"positioning accuracy provides superior positionability . This positioner with Leslie's T2 Triminsures accurate step changes in less than asecond with no overshoot or undershoot.

The characterized T2 Trim also hasLeslie's Class 8 Shutoff, less than one drop perminute at rated DP. With no seat leakage, thereis no unnecessary loss of steam temperature.Leslie's solution can turn a 15ºF band oftemperature to a 3ºF band, saving the other-wise lost energy. Nominal savings for drumunits of 400MW is $4500 per degree per year.

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AttemperatorSprayValveApplications

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24

A subsidiary of International, Inc. APPLICATION GUIDEGland Seal Steam Control Valve

PurposeThe Gland Seal Steam Control Valves are

used to maintain a constant steam pressure of5-10 psig in the gland to seal air from theturbine. At low loads (<25%) steam must besupplied to the gland, at high loads the turbinegland is self supplying. During normal operationexcess steam is vented to the condenser, lowload supply comes from main or auxiliarysteam sources.

Operating ConditionsThe supply valve sees high pressure steam

from superheater outlet or reheat steam fromadjacent unit. These valves are throttling a lowflow at high pressure drops. They are closedduring normal unit operation. The exhaust orvent valve, vents excess steam at 7-10 psig tothe condenser. Typically these valves operate in

a split range mode. One pressure control signaleither loads or vents steam to the gland.

Leslie SolutionThis application is ideal for Leslie's

Aeroflow Control Valve. The major problemswith the supply valves is seat leakage due towire draw of plug and seat ring. They supplysteam when it's not needed and vent energy tocondenser (lost efficiency).

Leslie Class VIII Shutoff prevents wiredraw, lost efficiency and frequent mainten-ance/repair. Leslie characterized trim allows forthe proper Cv for this low flow high pressuredrop application.

The vent valve typically has been a globevalve, but a K-Max will work well in thisapplication.

Main Steam Pressure1000-3600 psig

Auxiliary Steam Pressure300-750 psig

To Condensor

25

A subsidiary of International, Inc. APPLICATION GUIDETurbine Bypass Valve

PurposeThe Turbine Bypass Control Valve is used

to divert steam from the turbine to thecondenser or atmosphere. In nuclear plants itbuffers the slow response of the reactor toturbine trip or rapid load changes. In fossilfueled plants it is used for startup and toprevent solid particle erosion to the turbine atlow flows. The bypass system provides theability to avoid a boiler/reactor trip in the eventof system load rejection.

Operating ConditionsThis service sees turbine throttle pressures

and temperatures, typically of 1500 to 3600 psiat 1050ºF on fossil units. The outlet pressure isvery low, although some fossil bypassapplications are to the reheater section at 600to 900 psi. This service will see thermal shocksand requires tight shutoff with fast response.

Leslie SolutionThis application is ideal for Leslie's

Aeroflow Control Valve. The major problemswith bypass valves is seat leakage with wiredraw of plug and seat ring. Leslie's Class VIIIShutoff pays for itself in saved maintenanceand energy.

Many bypass applications require onesecond stroke time. Hydraulic Actuators areoften required to obtain these speeds.Aeroflow's T2 Trim can obtain the requiredspeeds with less expensive actuation and stillmaintain stable control.

Common problems with turbine bypass arebinding and/or seal washout due to thermalcycling. Leslie's piloted trim self aligns the plug,cage and seat ring for positive seatingrepetitively. The top hung cage allows it toexpand freely through sudden wide variationsin fluid temperature. This tolerance for cageexpansion solves the typical problems seen incage retained designs such as cage warping,plug binding, galling, and crushed gaskets.

SuperheaterMain Steam

Pressure1000-3600 psig

Steam Pressure400-1100 psig

Reheat Bypass

Main SteamBypass

Main Steam/Reheat Bypass

Reheater

Condensor

26

A subsidiary of International, Inc. APPLICATION GUIDEAuxiliary Steam Pressure Reduction

There are many applications for steampressure reduction in the conventional fossilfired generation plant. Some applications callfor high pressure drops and intermittentoperation; soot blower header pressure control,building heat regulator and pegging steam todeaerator.

Soot Blower Header PRVFossil fired plants use soot blowers to

remove soot from the boiler tubes to increasethermal efficiencies. Soot blowers are hightemperature pipes (lances) which traverse theboiler blowing superheated steam on the boilerwalls to remove scale and buildup. Typicallythere are 20 or more lances for one boiler.

Each bank of lances has a header tosupply them 200 to 500 psi steam. Steam issupplied to the header from superheater outlet.The steam PRV sees a high pressure drop andvery intermittent operation. This application isclosed most of the time and sees rapid loadswings as soot blowers are inserted andretracted.

This application is ideal for Aeroflow T2

Trim. Tight shutoff is required to keep seatleakage and wire draw from happening. Seatleakage will cause the header to build pressurewasting steam and blowing safetys. The speedand accuracy of T2 Trim will keep up with therapid swings for tight pressure control,preventing the safetys from lifting. We cansupply low makeup pressure requirements by

throttling through the pilot. The DPS Positionerprovides precise positioning of the stem.

Building Heat PRVMany plants use extraction steam for

building heat. The application uses HP steamto provide 100-200 psi steam for buildingheating systems. The valve is closed in thesummer and used intermittently in the heatingseason.

Aeroflow's Class VIII Shutoff and noisecontrol options provide the long term solutionfor this application. Try to keep velocities below.5 Mach for noise and erosion concerns.

Deaerator Pegging SteamDeaerators use superheated steam to heat

and remove air from the condensate. Thisprocess uses 50 to 250 psi superheated steam.Normal supply is from a low pressure turbineextraction, but under trip conditions highpressure (1500 - 3000psi) superheated steam isused as backup.

This application is normally closed againsta high DP, Leslie's Class VIII Shutoff preventswear and unnecessary heat loss. Stable controland immunity to thermal shock add to thisapplication need. Aeroflow is the solution.

These are some of the applications whereAeroflow has solved difficult Power Plant valveproblems. There are many more waiting forsolutions. Find them and let us know.

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Auxiliary

Steam

Pressure

Reduction(SootBlowerPressure

Reducing)ValveApplication

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A subsidiary of International, Inc. APPLICATION GUIDE

28

A subsidiary of International, Inc.

Turbine & Header Drain Valves

PurposeIn addition to drain valves removing

condensate from low points in main steam,superheat and reheat piping, drains are alsorequired for the HP and IP turbines. Thepresence of condensate in the turbine atstartup or shutdown can be extremelydamaging.

At startup of the turbine, the turbine drainvalves are opened to insure that, at these lowtemperatures, any condensate that condensesin or before the turbine is immediately removed.As the steam temperature and pressureincrease the drain valves are gradually throttledclosed until full power is reached. Once theturbine is in full operation the drain valves arefully closed and a tight shutoff is desirable.

Operating ConditionsThe drain valve service is one of the most

severe applications for any valve in a powerplant. These valves normally see a wide rangeof conditions; first cool condensate, followedby ever increasing pressure and temperaturethat causes the condensate to flash into steamand ultimately high pressure and temperature

steam. The outlet condition is condenservacuum.

One of the main considerations in thisapplication is seat leakage. During turbineoperation this valve is closed against a highpressure with a vacuum on the outlet. Seatleakage is not only expensive from amaintenance standpoint but the cost ofgenerating turbine grade steam is expensive aswell.

The power industry has determined that athrottling control valve in this application willimprove the reliability and efficiency of this typedrain system.

Leslie SolutionAeroflow’s Zero leakage metal to metal

seat provides the solution for this application.With our piloted plug there is no friction whenseating, hydraulic lift for clean opening andthermal immunity for long life. The bestconfiguration for this application is an anglebody, in flow to close orientation, with anti-cavitation trim.

HP

Main Steam Pressure1000-3600 psig

Steam Pressure400-1100 psig

Reheater

to Condensor

MP

A subsidiary of International, Inc. APPLICATION GUIDE

29

Heater Drain Valve

PurposeFeedwater heaters are used in power

plants to preheat the feedwater usingextraction steam from the turbine. Heaters arearranged in a cascaded manner, so that steamand condensate are drained from a higherpressure (temperature) in one heater stage to alower pressure until the last stage drains to thecondenser.

The feedwater piping is coiled through theheater and surrounded by turbine extractionsteam. Below the coils condensate is collectedand drained off by the heater drain to insurethat condensate does not back up on the coils.

The heater drain valve is normally operatedthrough a local pneumatic level controller.Recent advances in control strategy have putthis control in the DCS. The heater drain valveis fail closed and has a redundant emergencydrain which is fail open.

Operating ConditionsThe drain valve controls condensate at

saturation temperature to a vessel at lowerpressure, flashing is always present. Highpressure heaters operate at 800-900 psi at850ºF down to the low pressure heaters at 100

psi and 400ºF. There could be a many as 6 or 8stages of heaters.

The flash dictates that line size globe valvebe used to control velocities. Usually C5 or C9material will be supplied to control erosion.Some high pressure heaters require 900# ANSI,most require 300 or 600#.

The emergency drains normally are closedagainst the extraction steam in the heater.These valves require tight shutoff and quickoperation.

Leslie SolutionThe turbine drain application traditionally

has called for a welded globe valve with C5 orC9 body to prevent flash erosion. Today theutility industry has selected a flanged CS bodyK-Max type rotary CV. This allows use of a CSbody with flow to close orientation and .2 or .4trim to keep flash in center of pipe and down-stream of valve body.

The emergency drain application is idealfor Leslie's Aeroflow Control Valve. The majorproblems with this valve application is seatleakage with condenser vacuum on outlet.Leslie's Class VIII Shutoff pays for itself insaved maintenance and energy.

HL

LC

IN

OUT

Feedwater

Heater Drain to lower pressure

EmergencyDrain

to Condensor

30

A subsidiary of International, Inc. APPLICATION GUIDE

APPLICATION ANSI Class Body Mat’l. Fail Plug Style Characteristic Shut-Off POS SOV Notes

WCB WC9 316SS Open Closed UBP BH BL PB T2 L EP QP

Feedwater Control Valve 600-2500 IV,V 1

Boiler Feedwater Startup Valve 600-2500 IV,V 1,2

Boiler Feedwater Recirc. CV 600-2500 ZERO 1,3,6,7

Superheat Spray Control 600-2500 ZERO 1

Reheat Spray Control 600-2500 ZERO 1,3

Turbine Bypass 900-4500 ZERO 4,6

Heater Drain 600-1500 ZERO 4,7

Auxiliary Steam Extraction 900-4500 ZERO 6

Soot Blower PRV 900-4500 ZERO

Steam Header Drain 900-4500 ZERO 7

Gland Seal Steam Control Valve 900-4500 ZERO

Header Condensate Drain 600-2500 ZERO 1,6

NOTES:1 Above 20-25 Ft/Sec use C92 Can use C3 Cage in FWCV and Eliminate3 Cavitation trim is usually required4 May need expander and plate to keep velocities < .5 Sonic5 Possible Les-Sonic Trim6 Could be angle body7 Integral Cage strainer may be required

Control Valve Selection Chart

APPENDIX

31

A subsidiary of International, Inc. APPLICATION GUIDEAPPENDIX

32

ASME B16.34-1996 TABLE 2-1.1RATINGS FOR WCB - A216

TABLE 2-1.1A STANDARD CLASSWorking Pressure by Classes, psig

Temperature, ºF 150 300 600 900 1500 2500 4500-20 to 100 285 740 1480 2220 3705 6170 11110

200 260 675 1350 2025 3375 5625 10120300 230 655 1315 1970 3280 5470 9845400 200 635 1270 1900 3170 5280 9505500 170 600 1200 1795 2995 4990 8980600 140 550 1095 1640 2735 4560 8210650 125 535 1075 1610 2685 4475 8055700 110 535 1065 1600 2665 4440 7990750 95 505 1010 1510 2520 4200 7560800 80 410 825 1235 2060 3430 6170850 65 270 535 805 1340 2230 4010900 50 170 345 515 860 1430 2570950 35 105 205 310 515 860 1545

1000 20 50 105 155 260 430 770Not recommended for prolonged usage above about 800ºF

TABLE 2-1.1B SPECIAL CLASSWorking Pressure by Classes, psig

Temperature, ºF 150 300 600 900 1500 2500 4500-20 to 100 290 750 1500 2250 3750 6250 11250

200 290 750 1500 2250 3750 6250 11250300 290 750 1500 2250 3750 6250 11250400 290 750 1500 2250 3750 6250 11250500 290 750 1500 2250 3750 6250 11250600 275 715 1425 2140 3565 5940 10690650 270 700 1400 2100 3495 5825 10485700 265 695 1390 2080 3470 5780 10405750 240 630 1260 1890 3150 5250 9450800 200 515 1030 1545 2570 4285 7715850 130 335 670 1005 1670 2785 5015900 85 215 430 645 1070 1785 3215950 50 130 260 385 645 1070 1930

1000 25 65 130 195 320 535 965

Not recommended for prolonged usage above about 800ºF

33

A subsidiary of International, Inc. APPLICATION GUIDEAPPENDIXASME B16.34-1996 TABLE 2-1.10

RATINGS FOR WC9 - A217

TABLE 2-1.10A STANDARD CLASSWorking Pressure by Classes, psig

Temperature, ºF 150 300 600 900 1500 2500 4500-20 to 100 290 750 1500 2250 3750 6250 11250

200 260 750 1500 2250 3750 6250 11250300 230 730 1455 2185 3640 6070 10925400 200 705 1410 2115 3530 5880 10585500 170 665 1330 1995 3325 5540 9965600 140 605 1210 1815 3025 5040 9070650 125 590 1175 1765 2940 4905 8825700 110 570 1135 1705 2840 4730 8515750 95 530 1065 1595 2660 4430 7970800 80 510 1015 1525 2540 4230 7610850 65 485 975 1460 2435 4060 7305900 50 450 900 1350 2245 3745 6740950 35 375 755 1130 1885 3145 5665

1000 20 260 620 780 1305 2170 39101050 20(1) 175 350 525 875 1455 26251100 20(1) 110 220 330 550 915 16451150 20(1) 70 135 205 345 570 10301200 20(1) 40 80 125 205 345 615

NOTE: (1) For welding end valves only. Flanged end ratings terminate at 1000ºF.

TABLE 2-1.10B SPECIAL CLASSWorking Pressure by Classes, psig

Temperature, ºF 150 300 600 900 1500 2500 4500-20 to 100 290 750 1500 2250 3750 6250 11250

200 290 750 1500 2250 3750 6250 11250300 285 740 1485 2225 3705 6180 11120400 280 725 1450 2175 3620 6035 10866500 275 720 1440 2160 3600 6000 10800600 275 720 1440 2160 3600 6000 10800650 275 715 1430 2145 3580 5965 10735700 275 710 1425 2135 3555 5930 10670750 265 690 1380 2070 3450 5750 10350800 260 675 1345 2160 3365 5605 10095850 245 645 1285 1930 3215 5355 9645900 230 600 1200 1800 3000 5000 9000950 180 470 945 1415 2355 3930 7070

1000 125 325 650 975 1630 2715 48851050 85 220 435 655 1095 1820 32801100 55 135 275 410 685 1145 20551150 35 85 170 255 430 705 12851200 25 50 105 155 255 430 770

NOTE: (1) For welding end valves only. Flanged end ratings terminate at 1000ºF.

34

A subsidiary of International, Inc. APPLICATION GUIDEAPPENDIXASME B16.34-1996 TABLE 2-2.2

RATINGS FOR CF8M - 316SSTABLE 2-1.10A STANDARD CLASS

Working Pressure by Classes, psigTemperature, ºF 150 300 600 900 1500 2500 4500

-20 to 100 275 720 1440 2160 3600 6000 10800200 240 620 1240 1860 3095 5160 9290300 215 560 1120 1680 2795 4660 8390400 195 515 1030 1540 2570 4280 7705500 170 480 955 1435 2390 3980 7165600 140 450 905 1355 2255 3760 6770650 125 445 890 1330 2220 3700 6660700 110 430 865 1295 2160 3600 6480750 95 425 845 1270 2110 3520 6335800 80 415 830 1245 2075 3460 6230850 65 405 810 1215 2030 3380 6085900 50 395 790 1180 1970 3280 5905950 35 385 775 1160 1930 3220 5795

1000 20 365 725 1090 1820 3030 54501050 20(1) 360 720 1080 1800 3000 54001100 20(1) 325 645 965 1610 2685 48351150 20(1) 275 550 825 1370 2285 41151200 20(1) 205 410 620 1030 1715 30851250 20(1) 180 365 545 910 1515 27251300 20(1) 140 275 410 685 1145 20601350 20(1) 105 205 310 515 860 15451400 20(1) 75 150 225 380 630 11301450 20(1) 60 115 175 290 485 8751500 15(1) 40 85 125 205 345 620

(1) For welding end valves only. Flanged ratings terminate at 1000ºF

TABLE 2-1.10B SPECIAL CLASSWorking Pressure by Classes, psig

Temperature, ºF 150 300 600 900 1500 2500 4500-20 to 100 290 750 1500 2250 3750 6250 11250

200 260 680 1365 2045 3410 5680 10220300 235 610 1220 1825 3045 5070 9130400 220 570 1140 1710 2850 4750 8550500 205 530 1065 1595 2660 4430 7790600 195 505 1010 1510 2520 4195 7555650 190 495 985 1480 2465 4110 7395700 185 485 970 1455 2420 4035 7265750 180 470 945 1415 2360 3930 7070800 180 465 925 1390 2320 3860 6950850 175 455 905 1360 2265 3775 6790900 170 440 880 1320 2195 3660 6590950 165 430 865 1295 2155 3595 6470

1000 160 420 840 1260 2105 3505 63101050 160 420 840 1260 2105 3505 63101100 155 405 805 1210 2015 3360 60451150 130 345 685 1030 1715 2860 51451200 100 260 515 770 1285 2145 38601250 90 230 455 680 1135 1895 34101300 65 170 345 515 860 1430 25701350 50 130 260 385 645 1070 19301400 35 95 190 285 470 785 14151450 30 75 145 200 365 610 10951500 20 50 105 155 260 430 770

(1) For welding end valves only. Flanged ratings terminate at 1000ºF

35

A subsidiary of International, Inc. APPLICATION GUIDEFCI 70-2 SEAT LEAKAGE

Class II = .5% Valve Rated Capacity Differential of 45 to 60 psiTest Medium Water

Class III = .1% Valve Rated Capacity Differential of 45 to 60 psiTest Medium Water

Class IV = 01% Valve Rated Capacity Differential of 45 to 60 psiTest Medium Water

Class V = 5 x 10-4 ml / min of water / in. seat diameter / psi DPTested @ Rated DifferentialTest Medium Water

Class VI = 1” .15 ml/min. 1 bubble/min.1.5” .30 ml/min. 2 bubble/min.2” .45 ml/min. 3 bubble/min.2.5” .60 ml/min. 4 bubble/min.3” .90 ml/min. 6 bubble/min.4” 1.7 ml/min. 11 bubble/min.6” 4 ml/min. 27 bubble/min8” 6.75 ml.min. 45 bubble/min.Differential of 50 psiTest Medium Air or Nitrogen

Leslie“ZERO” Less than one drop per minute, Tested @ Rated Differential

Test Medium Water

APPENDIX

36

A subsidiary of International, Inc. APPLICATION GUIDE

LIQUID BODY VELOCITY LIMITATIONCarbon Steel (WCB)Continuously Modulating or DP > 500 psi 20 ft/secIntermittent Modulating or DP < 500 psi 30 ft/sec2% Intermittent Flow 40 ft/sec

Alloy or Stainless SteelContinuously Modulating or DP > 500 psi 45 ft/secIntermittent Modulating or DP < 500 psi 60 ft/sec2% Intermittent Flow 90 ft/sec

Notes: Use Alloy or SS if flashing or cavitation existsBody erosion and noise will occur above these limits

Compressible VelocityNoise cannot be predicted >=Mach .5Carbon Steel Limit is .35 MachAlloy or SS Limit is .9 Mach

NOISE ATTENUATION

INSULATIONDECIBELREDUCTION

PIPE PIPE SCHEDULESIZE 10 20 30 40 60 80 100 120 140 160 STD XS XXS

1 — — — 0 — -3 — — — -6 0 -3 —1.5 — — — 0 — -3 — — — -6 0 -3 -92 — — — 0 — -3 — — — -7 0 -3 -93 — — — 0 — -3 — — — -9 0 -3 -94 — — — 0 — -5 — -6 — -7 0 -6 -96 — — — 0 — -4 — -6 — -8 0 -6 -108 — +2 +1 0 -2 -4 -6 -7 -8 -9 0 -34 -910 — +3 +1 0 -3 -4 -6 -8 -9 -10 0 -3 —12 — +3 +1 -1 -3 -5 -7 -9 -10 -11 0 -3 —14 +3 +1 0 -2 -4 -6 -8 -10 -11 -12 0 -3 —16 +3 +1 0 -3 -5 -7 -9 -10 -12 -13 0 -3 —18 +3 +1 -2 -4 -6 -8 -10 -11 -13 -14 0 -3 —20 +3 0 -3 -4 -7 -9 -10 -12 -14 -15 0 -3 —24 +3 0 -4 -6 -9 -10 -12 -14 -15 -16 0 -3 —30 +1 -3 -5 — — — — — — — 0 -3 —

Thickness Type Decibel Reduction

1" Thermal -42" Thermal -8

3.5" Thermal -10.55" Thermal -13

Cladding add -5

APPENDIX

CAT-AGP-0909