Valve Appreciation 2012

08/03/2012

1

Improving the world through engineering www.imeche.org Improving the world through engineering www.imeche.org 1

‘Valve Appreciation Seminar’

Aberdeen IMechE

Young Member’s Panel

Thursday 8th February

Bruce Taylor AMIMechE

&

Ronald Simpson AMIMechE


Agenda

• Valve Introduction

• Valve Fundamentals

• Basic Valve Design

• Valve Types

• Automation

• Pressure Control Valves

• Question Session

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Valve Introduction

• Valves Are Common Everyday Device

• Used For A Variety of Applications • Commercial

• Industrial

• Military

• Residential

• Transportation

• Definition of a Valve – A mechanical device which manipulates the fluid flow in systems comprising of pipes, vessels, apparatus and machines, by…

• Opening

• Closing

• Diverting

• Mixing

• Obstructing … the flow passage through itself.


Examples of Valves

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Family Tree of Valves

VALVE

Straight Line Rotary Deformation of

Flexible Member

Perpendicular to

Flow at Seating

Area

Longitudinal to the

Flow at Seating

Area

Through the

Obturator

Around the

Obturator

Typically

Perpendicular to

the Flow at the

Seating Area

Gate Valve Globe Valve

Needle Valve

Plug Valve

Ball Valve

Butterfly

Valve

Diaphragm

Valve

Pinch Valve

Stand Alone Types

Non Return Valves Safety and Relief

Valves Pressure Control

Valves

Swing Check

Duo Check Valve

Lift Check Valve

Axial Flow Check

Safety Valve

Relief Valve

Safety Relief Valve

Pressure Reducing Valve

Pressure Retaining Valve

Automatic Control Valve

Choke Valve


Describing A Valve

• Valves Are Described By:- • Manufacturer / OEM

• Type

• Size – Nominal Bore / Pipe Diameter

• Reduced Port or Full Port

• Pressure Class / Rating

• End Connection

• Body Arrangement

Flanged -

Raised Face

Ball Valve

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Describing A Valve Cont.

Nominal Bore Size

• The internal size of the bore through the valve

• Full Port – Constant bore through the valve, and same size as connecting pipe work to which the valve is fitted

• Unrestricted Flow

• Allows Pigging Operations

• Increased Weight & Material, Hence Cost

8” x 8”



Nominal Bore Size

• Reduced Port – The bore through the valve is smaller than the connecting pipe work to which the valve is fitted

• Saves Weight & Material, Hence Cost

• Increases Pressure Drop Across Valve

• Increases Fluid Velocity

• Turbulence

• Can accelerate erosion

• Increase Noise in the System

8” x 6”

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Pressure Rating

Defines the pressure at which the valve may be operated

• Determined by the Manufacturer

• Temperature range also stated

• Some standards set ratings that equal flanged end connection ratings

ANSI (American National Standards Institute)

150, 300, 400, 600, 800, 900, 1500 & 2500 lb’s

API (American Petroleum Institute)

2000, 3000, 5000, 10000, 15000 & 20000 psi

PN (Pressure Nominal)

6, 10, 16, 20, 32, 40, 50, 64, 100, 150, 250 & 420



End Connection

• Screwed

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End Connection

• Flanged

• Full Face



End Connection

• Flanged

• Raised Face

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End Connection

• Ring Type Joint (RTJ)



End Connection

• Compact Flanges – Spolok

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End Connection

• Hubbed / Clamp Connector



End Connection

• Welded Connection

• Butt-Weld

• Socket Weld

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Describing A Valve

Body Arrangement

The valve body is the main pressure containing element of a valve.

• The body may be more than one part

• Certain Valves, Notably Ball Valves, it is more applicable to describe the body arrangement.

• 1 Piece

• 2 Piece

• 3 Piece

• Top Entry ….etc.


¼ Turn Valves

• 90 Rotation

• Clockwise to Close

• Isolation

• Types

• Plug Valve

• Ball Valve

• Butterfly Valve

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Plug Valves

Plug

Body

Stem

Lower Cover / Bonnet


Plug Valves

Parallel Plug

• Cylindrical Shape

• Bonnet typically at the top

• Metal to Metal sealing or

• Soft Sleeve sealing e.g. PTFE

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Plug Valves

Taper Plug

• Conically Tapered

• Bonnet typically at bottom

• Metal to Metal sealing

• Lubricated

• Pressure Balanced


Ball Valves

Ball

Body

Adapter/ Closure

Bonnet / Transition Plate

Trunnion

Seat

Stem

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Ball Valves

Floating Ball

• Degree of Float

• Smaller / lower Class

• Less leak paths

• Pressure Forces the Ball on to Seat


Ball Valves

Trunnion

• External Trunnion

• Trunnion Plates

• Additional bearing support

• Suitable for Large Sizes

• Higher pressures

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Ball Valves

Top Entry

• Easy Maintenance

• Repair in-situ

• Robust Design

• Fewer Leak Paths

• Fewer Repair Options


Ball Valves

Seats

• Single Piston (SPE)

• Double Piston (DPE)

• Temperature v Pressure

• Lapping

• Soft or Metal

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Ball Valves

Possible Issues

• Galling

• Scoring

• Scale Build up

• Throttling

• Corrosion / Erosion


Butterfly Valves

Types

• Rubber Lined

• High Performance

• Double Flanged

• Wafer fit

• Lugged / Non Lugged

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Butterfly Valves

Offsets

• Concentric

• Single

• Double

• Triple


Linear Valves

• Linear Operation

• Stroke length related to NB size

• Isolation / Flow Control

• Types

• Gate Valve

• Globe Valve

• Needle Valve

http://www.hobbsvalve.com/triple-offset/evolution_evolution.html

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Gate Valves

Types

• Wedge

• Through Conduit

• Knife

• Expanding


Gate Valves

Wedge

• Tapered Gate

• Angled Seats

• Wedge clear when open

• Metal to Metal

Stem / Spindle

Bonnet

Gate / Wedge

Body Seat

Back Seat

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Gate Valves

Through Conduit

• Parallel Gate / Slab

• Hole through Slab as per NB size

• Floating Seats or

• Floating Gate

• High Performance

T-Nut


Gate Valves

Knife

• Commodity Valve

• Used for Slurry, Cement, etc

• Thin Construction

• Low Pressure

OS&Y

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Gate Valves

Expanding

• DBB

• Wedge Effect

• Constant seat contact

• Expand when fully Closed


Globe Valves

Globe

• Throttling

• Isolation

• Hard Facing (Stellite)

• Typically under / over flow

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Needle Valves

Function

• Isolation

• Flow control

• Instrumentation

• Metal to Metal Seal

• Typically Globe valve design


Double Block & Bleed

DBB

• Isolation

• Up and Downstream sides

• Compact Design

• Ball, Gate, Globe or Needle

• Intervention, Sampling, Diversion or Injection

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Hand Lever

T

R

F

T = F x R T = Torque F = Force R = Radius

Limited to Small or lower Class valves

6” 600#, 3” 1500#, 2” 2500# and below


Hand wheel

Functions

• Multi-Turn

• Linear

• Used in conjunction with Gearbox

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Gearbox

¼ Turn Multi-Turn


Gearbox

Bevel Gear Drive

Housing

Input Shaft

Worm Gear

Mechanical Stop Quadrant

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Gearbox

Advantages

• Compact

• Mechanical Advantage

• Used with a Hand wheel or

• Electric Motor

• Constant Torque


Typical Materials

Plug Valves

Externals Carbon Steel Forged / Cast

Trim Stainless Steel Carbon Steel ENP

Ball / TC Gate Valves

Externals Carbon Steel Stainless Steel Exotic (Duplex) Forged / Cast

Trim Stainless Steel Duplex Inconels

Gate / Globe Valves

Externals Carbon Steel Stainless Steel Exotic (Duplex) Cast

Trim Stainless Steel Duplex

Butterfly Valves

Externals Carbon Steel Stainless Steel Exotic (Duplex) Aluminium Bronze Cast

Trim Stainless Steel Carbon Steel Monels Aluminium Bronze

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Preventative Maintenance

Process Line

Barriers

Local Junction Box

Leak Detection Sensors

Strain Gauge

Actuator Pressure Transmitter

Plant Sub Station

Strain Gauge Module

Data Acquisition Unit

Network Connection

Options

• Cycling Valves

• Sealant Injection / Lubrication

• AE Leak Detection

• Condition Monitoring


Part II

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Safety Relief Valves

General Definition: A safety device which automatically vents fluid from an internally pressurised system, counteracting undesirable system over pressurisation.

Safety Valve – an automatic pressure relieving device actuated by static pressure upstream of the valve characterised by rapid full opening or ‘pop’ action. It is used on steam, gas or vapour service. Relief Valve – an automatic pressure relieving device actuated by static pressure upstream of the valve which opens in proportion to the increase in pressure over the opening pressure. It is used primarily on liquid service. Safety Relief Valve – an automatic pressure relieving device suitable as either a safety valve or relief valve, depending on application.

PSV’s

• Conventional

• Balanced Bellows

• Pilot Operated



Conventional PSV Balanced Bellows PSV

Plugged Vent Open Vent

Bellows

Nozzle

Disc

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Pressure Acts On Disc Pressure Overcomes Spring Force

• Pressure Vents

• Valve Reseats After Blowdown

Spring Force

Nozzle

Disc

Blowdown

Ring

Blowdown

Ring


Bellows

Disc Holder

Bellows Spindle

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Bellows Failure


Conventional And Balanced Bellows

• Working Pressure 90% of Set Pressure

Conventional PSV

• Can Be used with a Constant Back Pressure

Balanced Bellows PSV

• Operation Not Affected With Variable Back Pressure

Pilot Operated

• Working Pressure 95% (>98% in Some Cases) of Set Pressure

• Tolerate Very High Back Pressure > 50% of Set Pressure

• No Large Springs

• More Complex Design


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Dome Volume

B

A


Pilot Controller

Area B > Area A

Sensor Pipework


Seal Failures

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Explosive Decompression


Actuators

• ¼ Turn Rotary Actuators • Scotch Yoke

• Rack & Pinnion

• Helical Gear (Rotary Piston)

• Cam Type

• Multi Turn Rotary Actuators • Electric Type

• Hydraulic Motor / Worm

• Stepping

• Linear Actuators • Piston

• Diaphragm

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Actuators

• Operating Supply • Pneumatic

• Low Pressure (up to 12 Barg)

• Readily Available – Plant Air / Instrument Air

• Large Piston – Bulky – More Fire Protection

• Hydraulic

• High Pressure = High Torque Output

• Small Piston – Compact – Less Fire Protection

• Hydraulic Power Unit Required

• Electric

• Clean

• Instant Operation Over Great Distances

• Limited By Hazardous Zones


Actuators

Advantages and Disadvantages

Pneumatic

• Economical

• Can be Exhausted to the Atmosphere

• No Kinetic Energy – Unsuitable for Wedge Gate Valves

• Air Compressibility Limits Ability to Retain Position, Can Drift Position with Butterfly Valves

• Manual Override’s Can Create Problems On Large Valves, Due to High Forces to Overcome

• Moisture Causes Corrosion

• Dirt in Supply Damages Internals

• Low Fire Risk

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Actuators


Hydraulic

• High Operating Forces

• Incompressibility Of Fluid Enables Position Stability

• No Kinetic Energy – Unsuitable for Wedge Gate Valves

• Hydraulic Power Supply Systems are Costly

• Thermal Expansion of Fluid is High, Heavy Fire Protection Required

• Dirt in Supply Damages Internals

• Robust, Extremely Water Tight – Excellent for Sub-Sea


Actuators


Electric

• High Kinetic Energy

• Position Stability Due to Gearing Arrangement

• Operates Instantly, No Dirt or Moisture Transmission

• Manual Override is Simple

• Failure Mode is Stay-Put Only

• Vulnerability of Electrical Equipment an Cabling

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Actuators

• Configurations • Double Acting

• Power Required to Function Both Directions

• Single Acting – Spring Return

• Power Required to Function One Direction

• Spring Functions One Direction

• Supply-Failure Mode Types • Fail Open

• BDV Applications

• Fail Close

• ESDV Applications

• Stay Put


¼ Turn Rotary Actuators

Spring Can

Pneumatic Power Cylinder

Centre Housing

Pneumatic Spring Return

Pneumatic Double Acting

• Scotch Yoke

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Spring Can

Hydraulic Power Cylinder

Centre Housing


Hydraulic Double Acting

Hydraulic Power Cylinder


• Scotch Yoke



Scotch Yoke Actuator

Spring

Piston

Centre Housing

Piston Rod

Spring Rod

Yoke

Canted Yoke

Symmetrical Yoke

45

≈30

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Torque Characteristics

45 0 90

Rotation Angle

To

rq

ue O

utp

ut

Valve

Actuator

Valve

FoS No Motion

Scotch Yoke

Torque Vs. Angle of Rotation


Torque Characteristics

45 0 90

Rotation Angle

To

rq

ue O

utp

ut

Symmetrical Yoke

Canted Yoke

Valve

Scotch Yoke

Torque Vs. Angle of Rotation

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• Helical Type – Rotary Piston

• Hydraulic Supply

• Compact Design

Piston

Hydraulic Supply Port

Helical Gear

Hydraulic Supply Port

Belvel Spring

Double Acting

Spring Return Acting


Rack & Pinion

Piston

Rack

Pinion

Pneumatic Double Acting

• Two Pistons


• Two Pistons

Spring

Position Indicator

Adjustable Stops


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Rack & Pinion Variations

• Double Piston & Single Rack

• Single Piston & Rack

• Double Piston & Rack

• Good Characteristics for Butterfly Valves

45 0 90

Rotation Angle

To

rq

ue O

utp

ut

Actuator - DA

Butterfly Valve

Actuator - SR



Cam Type • Two Double Pistons

Connected By Tie Rods, Cam Between them, Fixed By a Shaft

• Constant Torque Throughout Stroke

• Can be supplied to give an Exact 90 Rotation

• Simple Construction

• Can Also Do 180 Rotation

Spring Can

Adjustable Stop Housing

Position Indicator

Spring Can Cam Piston

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Multi Turn Rotary Actuator

• Electric • Hydraulic Worm

Hydraulic Motor

Worm

Manual Hand Wheel

Position Indicator Electric

Controls

• Limits Can Be Set For:-

• Limit Switch

• Torque Setting

• Quarter Turn, Multi Turn & Stepping

• High Reduction Ratio

• Drive Close Capability



Stepping Actuator

• Primarily Used for Choke Valves

• Multi-Turn and Rising Stem

Over Ride

Hydraulic Cylinder

Multi-Cam

Pinion

Bevel Wheel

Position Indicator

Compensation Bellows

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Stepping Actuator

• Accurate Valve Positioning

• Constant Torque Out Put

Pneumatic Motor


Linear Actuators

Piston Type

• Also Called ‘Cylinder Actuators’

• Designed to Have Required Stroke

• High Linear Thrust

• Considered High Pressure Version of Diaphragm Actuators

• Spring Return – Open/Closed Function

• Double Acting – Can be Used on Control Valves to Give Good Position Holding

Cylinder Piston

Spring

Stem Clamp Yoke

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Linear Actuators

• Diaphragm Type

• Large Area & Light

• Accurate Control

• Excellent For Control Valves

• Limited Stroke

• Simple Construction

Air Connection

Diaphragm

Diaphragm Button

Adjustable Coil Spring

Spring Adjuster

O-ring Sealbox


Pressure Control Valves

What Are Control Valves?

A Valve That Regulates:-

• Flow

• Pressure

• Temperature

Also Know as:-

• Throttling Valve

• Regulating valve

Controller

Sensing Element

Control Valve

Pneumatic Positioner

and Actuator

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One Piece Body Casting

Seat Ring

Contoured Plug

Plug Guide

Body/Bonnet Gasket

Plug Stem

Bolted Gland

Stem Packing

Single Stage Low Duty



Contoured Trim Micro Spline

Flow Under Plug

• Prevents Bath Plugging

• Fluids Containing Solids

• Fluids Leaving Deposits

Small Chemical Injection

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Modular Body Casting

HF Guide

Plug

Plug Stem

Bolted Gland

Stem Packing

Body/Bonnet Gaskets

Seat


Cage Trim Styles

Ported Cage HF Single Stage

HF Double Stage HF Triple Stage

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Multi Pressure Drop Trim

Tiger Tooth Trim Labyrinth Trim


Choke Valves

What Are Choke Valves?

A High Performance Control Valve

Regulates:-

• Pressure

• Flow

Applications:-

• High Pressure

• High Temperature

• High Flow Rates

First Production Valve to Control Hydrocarbons

• Connected to Well Heads

• Used for Water Injection

• Gas Injection

• Chemical Injection

Choke

Wellhead

Actuator

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Choke Valves

Angled Body

Micrometer Barrel

Manual Choke Valve

Cage

Bonnet

Plug

Locking Screw

Plug

Bean

Sub Sea Choke

(Retrievable)

Choke

Actuator

Mandrel

Clamp

ROV

Receptacle


Choke Valves

Hydro Dynamic Energy Dissipation

• High Velocity Fluid Directed to Each Other – Impinging Flow

• Energy Dissipates – High Erosion Contained Within Trim

• Exotic Materials

• Tungsten Carbide

• Ceramic

• Stellite

Plug And Cage (Flowed Over)

• Production Application

Plug

Cage

CFD of Fluid Impingement in Trim

Plug

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Flow Through Trim

Simplified Flow Through Trim

Flow Through Multi Orifice Trim

Streamlines Contract as

Flow Approaches Restriction

Vena Contracta

(Minimum Flow Area)

Fluid At Max Velocity

Choked Flow

• Max Flow Rate is Achieved

• Flow is Critical

• Increasing ΔP Will Not Provide Additional Flow

• Choking Effect Caused By Bubbles of Vapour in The Vena Contracta


Normal

Cavitating

Flashing

P1

P2

PV

PVC’

Valve Inlet

Trim Inlet

Trim Exit

Vena Contracta

Valve Outlet

Stat

ic P

ress

ure

Cavatation & Flashing

Staged Pressure Drop

ΔP

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Normal

Cavitating

Flashing

P1

P2

PV

PVC’

Valve Inlet

Trim Inlet

Trim Exit

Vena Contracta

Valve Outlet

Stat

ic P

ress

ure

Cavatation & Flashing

Staged Pressure Drop

ΔP


Cavatation Degredation

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Flashing Erosion


Impact & Erosion

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Impact & Erosion


Questions?

Thanks For Listening

Please Feel Free to Approach us for Questions and Handle the Valve Models

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How do I join the YMP?!

Visit

http://nearyou.imeche.org/near-you/UK/Scottish-Region/Aberdeen-Young-Member-Panel

for more events information!

Come along to:

• Monthly Meeting – 1st Tuesday of Each Month

The Office – Crown Street

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[email protected]

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Documents

Valve Appreciation 2012