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WHEN ACCURACY MATTERS Introduction Introduction to to Control Valve Types Control Valve Types

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WHEN ACCURACY MATTERS

IntroductionIntroductiontoto

Control Valve TypesControl Valve Types

WHEN ACCURACY MATTERS

• IEC Definition: A power operated device which changes the fluid flow rate in a process control system. It consists of a valve connected to an actuator that is capable of changing the position of the closure member in the valve in response to a signal from the system

• ISA Definition: A power operated device which modifies the fluid rate in a process control system. It consists of a valve connected to an actuator mechanism that is capable of changing the position of a flow controlling element in the valve in response to a signal from the controlling system.

Control Valve DefinitionControl Valve Definition

WHEN ACCURACY MATTERS

5050PSIGPSIGTANKTANK

PCSupply

Steam

P1 = 75-100 psig

Positioner

Analog Electro-Pneumatic Control Signal4-20mA

Process Variable4-20mA

Where does a CV fit in the Control SystemWhere does a CV fit in the Control System

WHEN ACCURACY MATTERS

• Feature– Ruggedly built for high cycle

service

– Always provides tight shutoff

– Valve bore approximates line size

– Always provide system effect with travel change

– Used to alter flow in response to control signal

– “Absorbs "large amount of energy

• On-Off Valve– No

– Yes

– Yes

– No

– No

– No

• Control Valve– Yes

– No

– No

– Yes

– Yes

– Yes

Control Valve vs On/Off ValveControl Valve vs On/Off Valve

WHEN ACCURACY MATTERS

Typical Isolation Valves Typical Isolation Valves

HP Butterfly Full Port Ball Sleeve Lined Plug Manual Globe Manual Gate

WHEN ACCURACY MATTERS

Control Valve Hierarchy Control Valve Hierarchy

Pressure Drop

HPBV Ball Rotary Globe

Globe Severe Duty

WHEN ACCURACY MATTERS

Control Valve TypesControl Valve Types

• Reciprocating– Globe

– Angle

– Severe Service

• Rotary– Butterfly

– Ball

– Rotary Globe

WHEN ACCURACY MATTERS

Basic Butterfly ValvesBasic Butterfly Valves

Poor Control Valve

WHEN ACCURACY MATTERS

High Performance Butterfly ValvesHigh Performance Butterfly Valves

Better Control

WHEN ACCURACY MATTERS

Types of Butterfly ValvesTypes of Butterfly Valves

Concentric Centerline

Single Offset (Eccentric)

Double Offset (HPBV)

2

1

2

1

3

Tripple Offset

WHEN ACCURACY MATTERS

Ball ValvesBall Valves

WHEN ACCURACY MATTERS

Segmented Ball Segmented Ball Control ValveControl Valve

Un-Restricted Flow Path

Un-Restricted Flow Path

Partially Open

WHEN ACCURACY MATTERS

Segmented Ball ValvesSegmented Ball Valves

• Partial Ball – 90 Deg. Rotation• High Capacity & High Turndown• Characterized Segmented Ball• Single Metal or Soft Seat

Notice the Single Clamped Seat

Notice the Characterization

WHEN ACCURACY MATTERS

Eccentric Rotary GlobeEccentric Rotary Globe

WHEN ACCURACY MATTERS

CAMFLEX AnimationCAMFLEX Animation

WHEN ACCURACY MATTERS

Reciprocating Control ValvesReciprocating Control Valves

WHEN ACCURACY MATTERS

Single Port Unbalanced Single Port Unbalanced

• Globe Valve• Unbalanced Design• Post Guided• Lo-dB Trim • Class-IV & Class-V Shut-

Off• Flow To Open• Flow To Close

WHEN ACCURACY MATTERS

LEAKAGE CLASSESLEAKAGE CLASSES

• CL IV, Standard– .01% of Rated Cv

• CL V, Optional– Reduced Pressure Drop Capability Due

to Higher Seat Loads Required

• CL VI, Optional– Plug with PTFE Seal Ring

WHEN ACCURACY MATTERS

QUICK CHANGE TRIMQUICK CHANGE TRIM

• Maintenance Advantage

• Seat Ring Held in Place by the Seat Ring Retainer (A Type of Cage)

• Seat Ring Gasket Required

WHEN ACCURACY MATTERS

TRIM TYPESTRIM TYPES

• Contoured Trim– Full Area– Reduced Area

• Single Stage Lo-dB and Anti-Cavitation

• Two-Stage Lo-dB and Anti-Cavitation

WHEN ACCURACY MATTERS

LOW NOISE PRODUCTSLOW NOISE PRODUCTS

• LO-DB Trim Reduces the Sound Level up to 15 dBA Over Conventional Trim, Depending on the P1/P2 Ratio.

SINGLE-STAGE Lo-dB TRIM

WHEN ACCURACY MATTERS

Angle Single Port UnbalancedAngle Single Port Unbalanced

WHEN ACCURACY MATTERS

Venturi Seat RingVenturi Seat Ring

Extreme Conditions

High Pressure Drops

Sever Coking Conditions

Flashing Liquids

Emergence Blow Down

WHEN ACCURACY MATTERS

Single Port Balanced Single Port Balanced

• Globe Valve

• Fully-Balanced Design

• Cage Guided

• Composite Polymer Balancing Seal

• Class-V Shut-Off

• Flow To Open

WHEN ACCURACY MATTERS

Single Port BalancedSingle Port Balanced

WHEN ACCURACY MATTERS

CAGE GUIDED VALVESCAGE GUIDED VALVES

• The cage provides positive alignment and control of the plug

• The cage can modify or “characterize” the flow

The Cage Serves Two Major Functions

WHEN ACCURACY MATTERS

CAGE GUIDED - PRESSURE BALANCEDCAGE GUIDED - PRESSURE BALANCED

TYPICAL APPLICATIONS• Clean Process Fluids• High Pressure, High Temperature, Noise, and

Cavitation

LIMITATIONS• Slurries or Gritty or Dirty Processes• Less Capacity Compared to Rotary Valves• Larger and Heavier than Most Rotary Valves

WHEN ACCURACY MATTERS

CAGECAGE

• Acts as Sealing Surface for Plug Seal Ring

• Retains Seat Ring

• Provides Throttling Orifice

• Guiding Surface

WHEN ACCURACY MATTERS

SEAL RINGSSEAL RINGS

• Metal Seal Ring– Class II – Temp: -320oF to 650oF

• PTFE Seal with Backup– Meets Class IV Seat Leakage– Temp: -20oF to 300oF

• Graphite Seal Ring– Meets Class IV Seat Leakage– Temp: -320oF to 1050oF

WHEN ACCURACY MATTERS

Pressure Energized Seal RingPressure Energized Seal Ring

• Pressure Energized PTFE Plug Seal

• Class V Leakage• Max Temp: 450oF

(600oF)• Uni-Directional• Higher Shutoff

Capability

WHEN ACCURACY MATTERS

AUXILIARY PLUGAUXILIARY PLUG

• Flow-To-Close Direction Only

– Approx. 10 dB Less Attenuation Than F-T-O

• Tight Shutoff at High Temperature

• Class IV, Class V Leakage

• “Dead” Travel in Closed Position = 0.050”

WHEN ACCURACY MATTERS

AUXILIARY PLUGAUXILIARY PLUG

• Cage Guided• Balanced• Single Seated• Captured Seat Ring (QC)• Pilot Trim

Stem

Packing Ring (S)

Cage

Balancing Seal

Packing Follower

Auxiliary Pilot Plug

Body

Seat Ring

Guide Bushing

Plug (Main)

Bonnet

WHEN ACCURACY MATTERS

Double Port (Semi Balanced)Double Port (Semi Balanced)

WHEN ACCURACY MATTERS

3-Way3-Way

WHEN ACCURACY MATTERS

80000 Series 3 Way80000 Series 3 Way

80000 Series 3 Way

DivertingCombining

WHEN ACCURACY MATTERS

Bellows SealBellows Seal

WHEN ACCURACY MATTERS

Low / Micro FlowLow / Micro Flow

WHEN ACCURACY MATTERS

End ConnectionsEnd Connections

Raised Face (RF)

WHEN ACCURACY MATTERS

End ConnectionsEnd Connections

Weld Prep

Butt Weld

WHEN ACCURACY MATTERS

End ConnectionsEnd Connections

Socket Weld

WHEN ACCURACY MATTERS

End ConnectionsEnd Connections

Ring Type Joint (RTJ)

WHEN ACCURACY MATTERS

End ConnectionsEnd Connections

Clamp Connection

(Graylok,ReFlange)

WHEN ACCURACY MATTERS

End ConnectionsEnd Connections

Threaded (NPT,MS)

WHEN ACCURACY MATTERS

Flangeless

End ConnectionsEnd Connections

WHEN ACCURACY MATTERS

End ConnectionsEnd Connections

Separable Flange

WHEN ACCURACY MATTERS

Questions? Questions?