Type 28 Gas Seals System Presentation

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© John Crane

Type 28 Gas SealsRange introduction and operating principles

© John Crane

Programme Overview

John Crane Introduction

Dry Gas Seal Application Turbo-Machinery

Brief History of Dry Gas Seals

Seal Design & Operating Principles

T28 Product Range

T28 Gas Seal Configuration & Operation

Control & Monitoring Systems

Q & A

© John Crane

John Crane Introduction

© John Crane

Smiths Group plc

John Crane is a Division of Smiths Group plc• 6,400 Employees• £626 million sales 2008

Smiths Group plc is a forward-thinking, focused engineering company with worldwide market-leading positions in its four chosen areas of specialization

• Medical• Detection• John Crane• Flex-Tek & Interconnect

© John Crane

A Global Leader

For over 80 years John Crane has had a passion for innovation

We are the acknowledged world leader and the largest developer, manufacturer and provider of:

Products:• Engineered mechanical seals• Sealing support systems• Power transmission couplings• Engineered bearings

Solutions:• Service• Reliability contracts• Asset management solutions• Oil & water chemistry consultancy

© John Crane

Asia Pacific

Europe Middle East Africa

North America

LatinAmerica

America’s Europe Asia Africa

Organisation

© John Crane

184 facilities in 43 countries

20 manufacturing plants

Over 80 service centres

1350 customer support Ens.

JCMSD DevelopmentJCMSD ManufacturingJCMSD Sales/Service

SloughChicago

Organisation

FranceHamilton

Mexico Venezuela

Washington

Sao Paulo

Italy

GermanyCzech Rep.

TianjinOsaka

Singapore

Madras

SydneyVictoria

Quebec

Sales £500M

© John Crane

John Crane Korea

John Crane KOREA는 1988년에 John Crane이 100% 투자하여한국내에설립되었고, 현재서울 Headquarter , 부산 Factory & Sales Office , 여수 Sales Office 를운영하고있으며 Sales Technical Engineer가전국에서활동중입니다.

John Crane KOREA는 Engineering Expertise , Technical Service, Global Supply Channels , Contracted Seal Reconditioning , Alliance 등의 Capability를갖고있습니다.

© John Crane

Established in 1988

Wholly-owned Smiths subsidiary

Headquarter in Seoul

Factory & Sales office in Pusan

Sales office in Yeochun

Integrated Flexibox Korea in 1999

John Crane Korea

Profile

© John Crane

Head Office in Seoul

© John Crane

John Crane Facility in Busan

© John Crane

Workshop in Busan

© John Crane

Sales Offices

Sales in Busan

Sales in Yosu

© John Crane

Mechanical seals Power transmission couplings Sealing support systems Spares

Running spares Repair Retro-fit

Asset management Seal management Stock management

KNOWLEDGE SERVICE EXPERIENCE

Value Added Solutions

John Crane has developed a world leading E-Business solution providing us and our customers with an opportunity

to achieve mutual benefits

© John Crane

Dry Gas Seal Application Turbo-Machinery

© John Crane

Extraction & ProductionOffshoreOnshore

Gas Gathering &TransmissionGas TreatmentGas StoragePipelineLNGGTL

RefineriesCatalytic ReformerHydrotreaterHydrocrackerFluid Catalytic CrackerGTL

Petrochemical PlantsEthyleneMethanolButyl Polymers

Organic ChemicalsAmmoniaUreaAcetylsNitric Acid

Dry Gas Seal Applications

© John Crane

Type 28XP

Type 28AT

Type 28GP

Compressors Type 28GP/AT

Pumps

Steam Turbines

Turboexpander

Type 28LD Type 28SC

Type 28VL Type 2800 Type 2800E

Type 285 Type 5620USP

Type 28ST

Type 28SST

Mixers Blowers

Non-Contacting Seal Products

Type 28EXP

Gas TurbinesType 28GT

Type 28LDCK728/738Type 5280

© John Crane

Type 28ATType 28AT

Gas Compressor Sealing

© John Crane

Turbomachinery Product

John Crane Dry Running Gas Seal

CompressorsCompressors

© John Crane

Dry Gas Seal Applications

A between bearings compressor normally contains two Type 28 gas seals

© John Crane

Gas Seals in a Compressor

CompressorCompressor

Gas SealGas SealGas SealGas Seal

© John Crane

Typical Compressor

ManMan--Turbo CompressorTurbo Compressor

© John Crane

Typical Compressor

Nuovo Pignone 2BCLNuovo Pignone 2BCL

Diaphragm BundleDiaphragm Bundle

© John Crane

Compressor Train – Nuovo Pignone

© John Crane

Compressor Train - MHI

© John Crane

-- Increased Increased safetysafety

-- 98% 98% power savingspower savings

-- 97% 97% reduction in gas lossesreduction in gas losses

-- Eliminate contaminationEliminate contamination

-- Considerable Considerable reliabilityreliability improvementimprovement

-- SimpleSimple pipe work / support systempipe work / support system

-- No seal oil consumption No seal oil consumption -- $US500k$US500k

Dry Gas Seal Benefits over Oil Seals:Dry Gas Seal Benefits over Oil Seals:

DGS Benefits

© John Crane

Brief History of Dry Gas Seals

© John Crane

Once Upon a Time ...

John Crane founded in 1917 – Chicago, Illinois, USA

Crane Packing Limited established in Slough, England, UK, in 1923, by Frank Payne - the Company President.

Enlarged Berwick Avenue Works Enlarged Berwick Avenue Works Slough 1936Slough 1936

Frank PayneFrank Payne

© John Crane

Type 28 Gas Seal Milestones

1968 First patent 1975 First field applications 1981 First beam type compressor 1985 First steam turbine 1985 First offshore 1986 First H2 recycle compressor 1991 Bi-directional seal 1992 XP seal - 123 to 200 bar 1994 Type 82 separation seal introduced 1995 First H.P. re-injection 1997 Worlds Largest 330mm Gas Seal 1998 400 bar seal test 1998 100,000,000 Operating hours 2000 T28 EXP 350bar Tandem Seal 2002 First fully operation service centre commissioned 2004 Infrastructure investment for 500mm seal + 5 service centres operational 2005 £3m investment in testing and development facilities 2005 Reliability team founded 2005 425 bar EXP seal with independently verified performance 2006 5 new test rigs commissioned 2007 Global service centre network 2008 Next generation separation seals T83/T93FR launched

© John Crane

0

50

100

150

200

250

300

350

400

450

1985 1990 1995 2000 2005

Pres

sure

(Bar

)Gas Seal Performance Progress

AT TripleXP Tandem

XP Triple

XP Quad

EXP Tandem

(Cran

ite &

ADC)

AT Tandem

© John Crane

John Crane invented the dry gas seal 30 years ago. Gas seals have revolutionised turbomachinery sealing

Gas seals are installedin the majority of newcentrifugal compressors Gas seals are fitted as

standard by all majorcompressor OEMs Over 20,000 gas seals supplied Over 200 million operating hrs

Type 28 Gas Seal Experience

© John Crane

Manufacturing Sites - Dry Gas Seals

= Dry Gas Seal Manufacturingand Reconditioning

JC UK, Slough

JC Inc, ChicagoJC Japan, Ritto

© John Crane

Sales and Service Sites

= Regional DGS Repair & Test Centres

JC Brazil

JC NorwayJC Russia

JC Saudi Arabia

JC Tianjin

JC Singapore

© John Crane

Dry Gas Seal Operating Principles

© John Crane

UNIDIRECTIONALSPIRAL GROOVE

BIDIRECTIONAL SPIRAL GROOVE

Spiral Groove Comparison

Operating Principles

© John Crane

Spiral Groove Dry Gas Seals

Features

•Cartridge seal - relatively simple to fit

•No wet seal system

•Gas lubricated – usually by the process gas

•Non-contacting faces

© John Crane

Mating Ring

Primary Ring

ShaftShaft

Type 28 Principles of Operation

Spiral Groove

© John Crane

clockwise shaft rotation

outer diameter

Opposingface innerdiameter

Innergroove

diameter

spiral groove

Sealingdam

Rotating Mating Ring

Spiral Groove Sealing Surface

© John Crane

Direction of Rotation

Spiral Groove Pattern

The Spiral Groove pattern is uni-directional only

Gas is pumped inwards by rotating spiral groovesMating Ring

Gas is compressed & Pressure increases to set gap

© John Crane

Hydrodynamic Lift Optimisation -Spiral Groove

InterfaceInterfacePressurePressure

Face Face ProfileProfile

Face ODFace OD

Face IDFace ID

GrooveGrooveGrooveGroove

DamDam

GrooveGroove

GrooveGroove

RotationRotation

© John Crane

Spiral Groove Geometry

Optimised spiral groovesOptimised spiral groovesMaximum lift pressure generated.Maximum lift pressure generated.

CStedy bespoke design and analysis tool

© John Crane

Hydrodynamic Lift

© John Crane

Grooves for Dry Gas Seals

Spring LoadedCarbon Face

Rotating Seatwith RecessedGrooves of Micrometers Depth

Sealing Interface Film Thickness of SeveralMicrometers

© John Crane

Dry Gas Seal Technology

Bi-directional Rotation Seal

John Crane Type 28ATBD / 28XPBDJohn Crane Type 28ATBD / 28XPBDHigh Performance BD Profile

© John Crane

Bi-Directional Groove Pattern

Type 28BD PatternType 28BD Pattern

© John Crane

Type 28 Principles of OperationBi-Directional Spiral Groove

Direction of Rotation Gas is induced towards thecenter.

Gas is Compressed &Pressure increases toset Gap.

Sealing Dam

© John Crane

Type 28BD Improved Groove

© John Crane

Why Use Grooves?

The Opening Load is the summation of the Hydrostatic force and the Hydrodynamic force. Hydrostatic pressure is generated by an

external source and controlled by the balance ratio of the seal. Hydrodynamic pressure is self-generated where

the pumping and compression action is created by the rotating grooves. Hydrodynamic pressure increases the operating

film thickness and the film stiffness of the sealing gap. Hydrodynamic pressure maintains the non-

contacting sealing interface. Hence zero wear and low frictional heating.

© John Crane

SPIRAL GROOVE

Spiral Groove Comparisons

BI-DIRECTIONALUNI-DIRECTIONAL SPIRAL GROOVESPIRAL GROOVE

© John Crane

Spiral Groove Dry Gas Seals

Some of the Benefits•Non-contacting

•no wear - life of equipment (refurb 3-5 years)• increased reliability - less downtime•reduced maintenance•reduced heat generation - no cooling

•Gas lubricated•no oil system - reduced weight, increased space,

reduced maintenance• low power consumption - typically <5kW• improved operational safety.

© John Crane

The spiral grooves are the heart of the The spiral grooves are the heart of the nonnon--contacting designcontacting design

Precision depth grooves generate liftPrecision depth grooves generate lift No wear or frictional heat generationNo wear or frictional heat generation Grooved component rotates in Type 28Grooved component rotates in Type 28

Spiral Groove Principles

© John Crane

Sealing Interface (Normal Gap)

Closing Force Opening Force

Compression

Expansion

Approx. Gap = 0.003mm

Spring Loadand Hydrostatics

© John Crane

Sealing Interface (Reduced Gap)

Closing ForceIncreased Opening Force

© John Crane

Sealing Interface (Normal Gap)

Closing Force Opening Force

Compression

Expansion

Approx. Gap = 0.003mm

Spring Loadand Hydrostatics

© John Crane

Sealing Interface (Increased Gap)

Closing ForceReducedOpening Force

© John Crane

Sealing Interface (Normal Gap)

Closing Force Opening Force

Compression

Expansion

Approx. Gap = 0.003mm

Spring Loadand Hydrostatics

© John Crane

John Crane – World Leader in Dry Gas Seal Technology

© John Crane

T-28 Dry Gas Seal Design Future

© John Crane

Shrouded drive ring to contain rotating mating ring

Mating ring positively driven on outside diameter

Distortion free Retainer with profile milled drive lugs..

Type 28AT Design Features

© John Crane

Elastomer o-rings Controlled contact

Large diameter multiple springs prevent buckling

Tolerance strip to centralise mating ring on support sleeve accommodating thermal, pressure and centrifugal effects.

Type 28AT Design Features

© John Crane

Secondary Secondary VentVent

Primary VentPrimary Vent Filtered Process Filtered Process GasGas

Type 28AT Tandem Seal

Tolerance StripsTolerance Strips

BearingsBearings Process GasProcess Gas

© John Crane

Centring Devices

Canted CoilCanted CoilStandard Standard Tolerance Tolerance StripStrip

Finger SpringFinger Spring

© John Crane

Compliant balanced stationary carbon primary ring design providing maximum flexibility

Logarithmic spiral or bi-directional

grooves

Tungsten carbide or silicon carbide rotating mating ring

Type 28AT Design Features

© John Crane

Type 28AT Seal Design Features

Compliant Compliant balanced balanced stationary carbon stationary carbon primary ring design providing maximum primary ring design providing maximum flexibilityflexibility

Logarithmic spiral or Logarithmic spiral or bibi--directional directional

groovesgrooves

Tungsten carbide or silicone carbide Tungsten carbide or silicone carbide rotating mating ringrotating mating ring

© John Crane

T-28 Dry Gas Seal Product Range

© John Crane

A between bearings compressor typically comprises two type 28 Dry Gas Seal cartridges.

DGS Applications

© John Crane

DGS Application Range

John Crane DGSOperating Range

Temp: -140 to +315°CPressure: to 425 BargSpeed: to 200m/sShaft: to 330mm

© John Crane

Type 28 AT for duties up to 82 bar*

Carbon seal faces

Elastomeric ‘O’ RingSecondary seal

Explosive decompression at High Pressure!

Chemical Attack! *some specific designs to 120 bar

© John Crane

Seal Configuration & OperationGas Seals

© John Crane

Type 28AT Single Seal

Often external labyrinth

•mainly to prevent ingress of bearing oil

•process gas is non-toxic

© John Crane

Type 28AT Single Seal

Single seal configuration is used mainly with nonSingle seal configuration is used mainly with non--hazardoushazardousgases such as air, nitrogen and carbon dioxide.gases such as air, nitrogen and carbon dioxide.

Process GasProcess GasBearingsBearings

Maximum Maximum DynamicDynamicPressure:Pressure:82 bar g82 bar g

© John Crane

Type 28AT Single Seal Cartridge

Filtered Process Gas

Simplest arrangement for lower cost sealing of non-hazardous process gases

© John Crane

Type 28AT Tandem Seal

Flammable gases

Hazardous gases

Low toxicity gases

90 - 95% applications use tandem seals

© John Crane

Secondary VentSecondary Vent Primary VentPrimary Vent Filtered Process GasFiltered Process Gas

Type 28AT Tandem + Labyrinth

BearingsBearings

NN22 PurgePurge

© John Crane

Type 28AT Tandem Seal Cartridge

N2 Purge Secondary Vent Primary Vent Filtered Process Gas

Bearing Process Gas

For sealing of non-hazardous process gases, with second seal for controlled shutdown in the event of seal failure

© John Crane

Tandem seal with intermediate Labyrinth configuration isTandem seal with intermediate Labyrinth configuration isused with toxic, flammable and hazardous gases.used with toxic, flammable and hazardous gases.

Tandem with Labyrinth

Secondary VentSecondary Vent Primary VentPrimary Vent Filtered Process GasFiltered Process GasNN22 BufferBuffer

© John Crane

Labyrinth

© John Crane

Tandem Type 28AT with Intermediate Labyrinth

N2 Purge Secondary Vent

N2 Purge

Primary Vent Filtered Process Gas

For sealing of hazardous process gases, with controlled leakage to flare, atmospheric emissions limited to process gas combustion products

© John Crane

Inboard seal failure will cause process gas leakage to atmospherInboard seal failure will cause process gas leakage to atmospheree

Tandem with Labyrinth

Secondary VentSecondary Vent Primary VentPrimary Vent Filtered Process GasFiltered Process GasNN22 BufferBuffer

© John Crane

With external Type 82 or double purged labyrinthWith external Type 82 or double purged labyrinthNo process gas leakage to atmosphereNo process gas leakage to atmosphere

Tandem with Labyrinth + Type 82

Secondary Secondary VentVent Primary VentPrimary Vent Filtered Process GasFiltered Process GasNN22 Buffer (1)Buffer (1)NN22 Buffer (2)Buffer (2)

© John Crane

Type 28AT - Double Seal

Used for highly toxic or abrasive process gases and Used for highly toxic or abrasive process gases and compressors with very low suction pressurescompressors with very low suction pressures

BearingsBearings Process GasProcess Gas

NN22 Barrier at 2 bar above Barrier at 2 bar above process pressureprocess pressure

© John Crane

Type 28AT Double Cartridge

N2 Purge Vent N2 Buffer

Bearings Process Gas

For sealing of hazardous process gases, with zero emissions to atmosphere

© John Crane

Type 28AT / 82 - Double Seal

Used for highly toxic or abrasive process gases and Used for highly toxic or abrasive process gases and compressors with very low suction pressurescompressors with very low suction pressures

BearingsBearings Process GasProcess Gas

NN22 Barrier at 2 bar above Barrier at 2 bar above process pressureprocess pressureNN22 BufferBuffer VentVent

© John Crane

Type 28AT Tandem + Type 82

Secondary VentSecondary Vent Primary VentPrimary Vent Filtered Process GasFiltered Process Gas

BearingsBearings

NN22 BufferBuffer

© John Crane

Type 82 Barrier Seal

NN22 at 0.4 bar differentialat 0.4 bar differential

© John Crane

Type 82 Bushing Upgrade - the Type 83 Barrier Seal

Improved Product - Type 83 Barrier Seal

Carbon Segments

Garter Spring

Wave Spring

© John Crane

Basic System

© John Crane

Control & Monitoring System of

Dry Gas Seals

© John Crane

Dry Gas Seal Control SystemDesign - Engineering - Manufacturing - Test

- All done in Singapore

Control and Monitoring System

© John Crane

Typical Nuovo Pignone Panel

© John Crane

Control & Monitoring System :

• Filtration of Buffer Gas

• Regulation of Buffer Gas

• Monitoring of Seal Performance

Control and Monitoring System

© John Crane

Key System Functions

Filter

Control

Measure

Measure Control

Measure

Bearing

© John Crane

FILTEREDSEALGAS

N2 PURGEGAS

SECONDARYLEAKAGE

PRIMARYLEAKAGE

SEPARATIONGAS

PRO

CES

S C

AVI

TY

BEA

RIN

G C

AVI

TY

28XP Tandem Seal with Intermediate Labyrinth Gas Seal Flow Diagram

© John Crane

SEALINGGAS

DGS Control SystemTandem Seal with Intermediate Labyrinth

PI PDIT PDIT

I/P

PDCV

FILTER 1

FIL. 2

PDITPDIT

PIT PDIT

PCV

PDCV

FE

FILTER 1

PI PI

SECONDARY

LEAKAGE

SECONDARY

LEAKAGE

PRIMARYLEAKAGE

PRIMARYLEAKAGE

FEFE

SEPARATION

/ PURGE

GASFI FIFILTER 2

COMPR.

DISCH

PURGE GAS

SEPARATION GAS

© John Crane

Gas Seal Support Systems

Primary Seal / Buffer Gas Supply

Primary Seal Gas Leakage

Secondary Seal Buffer Gas Supply

Secondary Seal Leakage

Separation Gas Supply

© John Crane

FILTER MODULE

PROCESSGAS

Process Gas

EXTERNALGAS

DGS Control System - Seal Gas Supply

© John Crane

FI FI

FILTER MODULE

PROCESSGAS

EXTERNALGAS

Process Gas

Filtered Process Gas

DGS Control System - Filtration

© John Crane

FI FI

FIFLARE

FILTER MODULE

PI PI

FO

PROCESSGAS

EXTERNALGAS

FO

FI

Process Gas

Filtered Process Gas

Process Gas to Flare

DGS Control System - Primary Vent

© John Crane

DGS Control System – Buffer Gas (Nitrogen) Injection

FI FIFI

FIFLARE

N2 SECONDARYFILTER MODULE

FILTER MODULE

PI PI

PCV

FO

PROCESSGAS

EXTERNALGAS

FO

FI

Process Gas

Filtered Process Gas

Process Gas to Flare

Filtered N2 Buffer Gas

FI

© John Crane

FIFI FIFI

FIFLARE

N2 SECONDARYFILTER MODULE

FILTER MODULE

PI PI

PCV

FO

PROCESSGAS

EXTERNALGAS

FO

FO FO

FI

Process Gas

Filtered Process Gas

Process Gas to Flare

Filtered N2 Secondary Gas

DGS Control System - Nitrogen Injection

© John Crane

FIFI FIFI

FIVENTFLARE

N2 SECONDARYFILTER MODULE

FILTER MODULE

PI PI

PCV

FO

PROCESSGAS

EXTERNALGAS

FO

FO FO

FI

Process Gas

Filtered Process Gas

Process Gas to Flare

N2 to Atmosphere

Filtered N2 Secondary Gas

DGS Control System - Secondary Vent

© John Crane

Basic System

1. Basic System

Primary Seal / Buffer Gas Supply Primary Seal Gas Leakage Secondary Seal Buffer Gas supply Secondary Seal Leakage Separation / Barrier Gas Supply

© John Crane

Functional Details Primary Seal / Buffer Gas Supply Module

• Pressure / Flow Control• Filter – Particulate or Coalescing Filter

Primary Seal Leakage Monitoring Module• Monitors primary seal leakage and initiates alarm / shutdown

Secondary Seal Buffer Gas Supply Module (option)• Supplies a flow of clean dry nitrogen to the outboard seal

Secondary Seal Leakage Monitoring Module • Monitors secondary seal leakage and initiates alarm / shutdown

Separation Gas Module• Supplies a flow of clean dry nitrogen to the Separation Seal

(barrier seal)• Monitors pressure or flow to the Separation Seal – Initiates Alarm

if it is low

Basic System

System Functions• Provide clean seal gas

(during normal operation)• Monitor Dry Gas Seal

Performance (leakage flow / pressure & separationseal pressure / flow) Seal / Buffer Gas

Supply ModuleSeal Leakage

Monitoring ModuleSecondary Seal

Buffer Gas ModuleSeparation

Gas Module

Basic

© John Crane

Primary Seal / Buffer Gas Supply Module

Seal Gas Filter

Flow Meter

PDCVInlet

To Seal

To Seal

© John Crane

Primary Seal Leakage Monitoring Module

Flow Meter

From Seal

To Flare

Leakage Blockwith Orifice

Pressure Transmitter

© John Crane

Secondary Seal Buffer Gas Supply Module

Buffer Gas Filter

Inlet

Flow Meter

To Seal

© John Crane

Separation Gas Supply Module

Separation Gas Filter

Pressure Regulator

Orifice Union

To Barrier Seal

© John Crane

John Crane Dry Seal Control System INOVIT

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