pipeline integrity through coatings and cathodic protection
TRANSCRIPT
ICEPIM 2015International Conference on Pipeline Integrity management
Pipeline Integrity through Coatings and Cathodic Protection g
A.S.Khanna
Corrosion Science & Engineering,
Department of Metallurgical Engineering
IIT Bombay
Oil & Gas InstallationsOil & Gas Installations
Oil & Gas production is the life line of every country. Oil & Gas production is the life line of every country.
T k th t t d d ti it i i d t kT k th t t d d ti it i i d t kTo keep the targeted production, it is required to keep smooth running of pipeline, without unplanned shutdowns and accidents.
To keep the targeted production, it is required to keep smooth running of pipeline, without unplanned shutdowns and accidents.
Oil & gas production starts from Deep wells, Offshore platforms, underground pipelines for crude/gas transportation and finally storage tanks and refineries.
Oil & gas production starts from Deep wells, Offshore platforms, underground pipelines for crude/gas transportation and finally storage tanks and refineries.
Though efforts are made to keep them best running, but the best way to maintain the asset is by proper Corrosion management
Though efforts are made to keep them best running, but the best way to maintain the asset is by proper Corrosion managementmanagement.management.
Corrosion Management
In simplest form, corrosion management like business or finance management is to look all issues required to control corrosion. These are described as :q
Better material selection methodology which at first place gives lower corrosion rates.
Protection by one of the controlling methods: Coatings, cathodic protection or use of inhibitors.
Online monitoring to check the health of the plant.
l l d h l lFailure Analysis and R &D input to improve the initial input on control strategy.
Periodic maintenance to repair faulty portionsp y p
PipelinesPipelines
Is the most important link to oil and Gas production.Is the most important link to oil and Gas production.
It is very important to keep this asset properly maintained without any leakageIt is very important to keep this asset properly maintained without any leakageproperly maintained without any leakage, failure or possibility of force shut down.properly maintained without any leakage, failure or possibility of force shut down.
So what is required:So what is required:
Pi li I t it A hPi li I t it A hPipeline Integrity ApproachPipeline Integrity Approach
Total Pipeline IntegrityTotal Pipeline Integrity
Higher Productivity
Greater safetyGreater safety
Longer Life
Pipeline AccidentsPipeline Accidents
In 1999 gasoline pipeline explosion in Bellingham,
W hi t kill d t hild d 18 ldWashington, killed two children and an 18‐year‐old man, and caused $45 million in damage to a city water plant and other property.
In 2000, a natural gas pipeline explosion near Carlsbad, New Mexico, killed 12 campers, including four children.
In 2006, damaged pipelines on the North Slope of Alaska leaked over 200,000 gallons of crude oil in an environmentally sensitive areaenvironmentally sensitive area.
Pipeline Safety IssuesFirst, those related to vandalism, pilferage, sabotage, terrorism. These issues cannot be tackled by Engineers. These may be taken care by additional security measures policing regular inspection ofcare by additional security measures, policing, regular inspection of
the asset.
Pipeline Maps A very important aspect to know the routes find outPipeline Maps – A very important aspect to know the routes, find out vulnerable areas, sensitive locations, new sites ready for development
etc.
•Taking care of leaks and defects during fabrication, installations, corrosion protection measures, especially coatings and cathodicprotection
Integrity management i t th d protection.
•Use of online monitoring techniques and also remote sensing provisions, such as pipeline data using SCADA etc.
•Periodic survey and detailed monitoring after definite intervals – such as Intelligent pigging after 5 years intervals
issues to the gas and crude handling and transportation
agencies: g p gg g yagencies:
Integrity Approach to Pipeline Coatings
Integrity MeaningIntegrity Meaning
How to apply the highest ethical standards to everyHow to apply the highest ethical standards to every aspect of the business.
• soundness of moral character honesty
Adherence to moral and ethical principles honesty.nd ethical principles
• sound, unimpaired, orperfect condition.
to preserve the integrity means,
Point to Ponder?Point to Ponder?
Is “Zero risk” is What is the effect of Ageing with time,
achievable in Engineering Structures?
Can we avoid Pipeline failures?
changing conditions, external threats and
always fear of “h ” ?“human errors” ?
Managing pipelines with better skill, training, inspection and repair is the only solution
Why Failure OccurWhy Failure Occur
Failure of Coatingg
Failure of CP ( Non availability of power)
Internal Corrosion ; SCC, SSCC
• Organizational failuresW d i• Wrong design
• Unsafe supervision• Poor maintenance
Reasons
Pipeline Failures ‐ StatisticsPipeline Failures Statistics
Failure in Onshore UK PipelinesPipeline Data USA 87‐2006
Phil Hopkins, J Pipeline Engg, 2008, p69
Pipeline Integrity Management Plan (PIMP)
Pipeline integrity management is a process for assessing and mitigating pipeline risks in an effort to reduce both the likelihood and consequences of incidents.
PIMP ‐ is a systematic and comprehensive process designed to provide information to effectively allocate resources for the appropriate prevention, pp p p ,detection and mitigation activities.
The program builds on the existing foundation ofThe program builds on the existing foundation of pipeline safety regulations covering design, construction, testing, operation and maintenance that has been in place for many yearsthat has been in place for many years.
How Pipeline Integrity Approach can help to achieve coatings which give design life without any failureg g y
Best coating selection is based upon the severity of the pipeline terrain.
Assure best surface preparation with proper surface cleanliness ( min. Sa2½ ), depth profile and min. impurity level.Sa ½ ), dep p o e a d pu y e e
•Uniform thickness•High cathodic disbondment
i i h lidProper application conditions
•Minimum or no holidays•High Impact strength•Good ageing characteristics ( in case PE Coating)
and optimized parameters to achieve a coating with :
Assured damage free transportation to the site
Good quality of Girth weld coating followed by proper ditching of the pipeline
Basic steps in the integrity management process
Identification of High consequence area (HCA)
High population density areas or
Difficult to evacuate facilities, such as hospitals, prisons or schools, churches, office buildings, or playgrounds.
Threat identification and risk assessment
Identification of Pipeline segments with possible threats of concerns such as heavy rains, land slide etc.
Risk AnalysisRisk Analysis
Potential hazards from facility operation are identified, and the likelihood and consequences of potential adverse events are estimated.
Each pipeline segment is given a numerical score based on the estimatedEach pipeline segment is given a numerical score based on the estimated risk.
‐‐‐‐ contd.
Baseline assessment planDevelopment of baseline data from the 10 year assessment of the pipelines.
• Inline inspection – “smart pig,” is run Integritythrough the pipeline to evaluate the pipe’s condition.
• Pressure test
Integrity assessment
M th d • Direct Assessment – a structured, multi‐step evaluation is conducted to identify potential problem areas.
Methods
RemediationPotential integrity concerns identified during the integrity assessment are evaluated and actions
are taken to eliminate the problems.
E l f Pi li I t itE l f Pi li I t itExample of Pipeline IntegrityExample of Pipeline Integrity
I i B i D i f Pi liIssues in Basic Design of Pipeline
Better pipeline material selection to avoid, pitting, SCC, sulphadic corrosion.Better pipeline material selection to avoid, pitting, SCC, sulphadic corrosion.
External Coatings – backed by Cathodic ProtectionExternal Coatings – backed by Cathodic ProtectionProtectionProtection
Internal Corrosion – by thin epoxyInternal Corrosion – by thin epoxyInternal Corrosion by thin epoxy coatings or by inhibitor injectionInternal Corrosion by thin epoxy coatings or by inhibitor injection
Chemical composition of various steels used for d d i liunderground cross country pipelines
Element
Grade
C Mn P S Cr Cu Ni Mo Al Si Nb/Ti Yield
Strength
UTS
(MPa)Grade Strength
(MPa)
(MPa)
X42 0.09 0.84 0.013 0.004 0.07 0.02 0.02 0.03 0.22 ‐ 290 414
0 014 0 009 0 03 0 03 0 02X46 0.09 1.28 0.014 0.009 0.02 0.03 0.03 0.02 0.25 ‐ 317 434
X52 0.09 1.31 0.012 0.006 0.009 0.07 0.003 0.03 0.25 ‐ 359 455
X56 0.12 1.27 0.017 0.004 0.07 0.14 0.19 0.02 0.26 ‐ 386 490
X60 0.12 1.48 0.013 0.004 0.010 0.09 0.02 0.008 0.27 ‐ 414 517
X70 0.13 1.71 0.012 0.001 0.07 0.07 0.02 0.05 0.30 ‐l 483 565
X100 0.064 1.56 0.024 0.0024 ‐ 0.38 0.54 0.28 0.03 0.13 0.089/ 690 760
0.011
CORROSION CONTROL IN PIPELINES
COATINGSCATHODIC PROTECTION
INHIBITORSINHIBITORS
External CoatingInternal Coatings
External Coating
Inhibitors
Cathodic Protection
Internal corrosion requirementsInternal corrosion requirements
Usually by adding inhibitors
In case of sour pipelines, internal coatings is a must.
In case of sea pipelines, internal metallic coating of Hastealloy is done
Internal CoatingsInternal Coatings
Main PurposeMain Purpose• To reduce the drag of fluid crude/gas• For Corrosion resistanceFor Corrosion resistance
RequirementsC ti h ld b thi dh t ifCoating should be thin, adherent, uniform thickness, abrasion resistanceStrong resistance to chlorides/sulphur based gasesShould be applied uniformly by some internal jet
t ft b t f tiarrangement after best surface preparation
COATINGS ‐ REQUIREMENTSCOATINGS REQUIREMENTS
High Corrosion resistanceg
High Cathodic Disbondment
High Impact resistanceHigh Impact resistance
High resistance to soil stresses
High Bending resistance and flexibility
Free of Holidays
High Dielectric Coefficient
Low water permeability
Classification of UCC Pipeline CoatingsCoal Tar Coatings
Fusion Bond Epoxy Coatings
Single layerSingle layer
Dual Layer
Three Layer PE
Polypropylene Coatings ( HT application)
Liquid Coatings
S l tl E iSolventless Epoxies
Elastomeric PolyethyleneTapes
Rehabilitation Coatings
Field Joint Coatings
Internal CoatingsInternal Coatings
How Pipeline Integrity Approach can help to achieve coatings which give design life without any failureg g y
Best coating selection is based upon the severity of the pipeline terrain.
Assure best surface preparation with proper surface cleanliness ( min. Sa2½ ), depth profile and min. impurity level.
•Uniform thickness•High cathodic disbondment
i i h lidProper application conditions and
•Minimum or no holidays•High Impact strength•Good ageing characteristics ( in case PE Coating)
p ppoptimized parameters to achieve a
coating with :
Assured damage free transportation to the site
Good quality of Girth weld coating followed by proper ditching of the pipeline
Bad surface finish leading to coating d fdefect
Surface CleanlinessSurface Cleanliness
b f f l dMust be free from oil and grease
NaCl
Standard to be followed SSPC
ISO 8501‐1 1998
How can this be achievedHow can this be achieved
Suitable Design of pipeline as per the terrain.g p p p
Dedicated supervising team to supervise all the operations of surface preparation coatings, packing
and transportation.
Third party inspection, PQT
Inspection of initial raw materials as per their specifications.
Schematic of Three layer PE CoatingSchematic of Three layer PE Coating
Sh t Bl ti P h tiFusion Bonding
Shot Blasting Pre‐heatingg
of Primer Epoxy
QuenchingQuality Check
Adhesive coat&Quality Check
PE Extrusion
Transportation
Coating ConditionsCoating Conditions
• Primer layer yElectrostatically charged epoxy powder on heated pipes (180‐220oC).
• Adhesive layer ‐ helps to bind FBE to PEPolyolefine is applied before the gel time of the
ti T t i b t 220 230oCepoxy coating. Temperature is about 220‐230oC. • PE Extruded LayerOn the Adhesive coated layer the PE is extrudedOn the Adhesive coated layer the PE is extruded over it. Its temperature is maintained at 238oC.
. Critical Issues –Maintaining uniformMaintaining uniform thickness
Application timings for dhAdhesive
And PE layer before FBE gels
Powder Coating of Epoxy
Extrusion Coating of Adhesive & PE
Relationship between temperature of Epoxy coating d th ti f dh i tiand the time of adhesive coating
Application WindowApplication Window
60
ve
40
on of a
dhesiv
20
ore applicatio
180 200 220 240
Time be
fo
200 220 240
Pipe Temperature
PRE‐QUALIFICATION OF THE COATING
Impact Test at every 1 foot followed by Holiday Detection
Complete Holiday Checking
Peel Test
Impact Test at every 1 foot followed by Holiday Detection
Checking the HolidaysCD Test 65oC ., ‐1.5V, 30 days
CD 65oC , ‐2.5V , 48h
Heat & UV Ageing of PE for 105 days
Indentation of PE at RT and 65oC.
ΔH of applied FBE to find out the extent of curing
Indentation Test for Pipeline CoatingsIndentation Test for Pipeline Coatings
Cathodic Disbondment TestCathodic Disbondment Test
Room Temperature Test 28 daysHigh Temperature Test – 65oC 28 daysPQT Test24h at 2 5V or 48h test at 1 5V24h at ‐ 2.5V or 48h test at ‐1.5V
Testing of FBE Powder PropertiesTesting of FBE Powder Properties
TG1, TG2 and ∆H
AUDIT OF HBJ PIPELINE 1999‐2000AUDIT OF HBJ PIPELINE 1999‐2000AUDIT OF HBJ PIPELINE 1999 2000AUDIT OF HBJ PIPELINE 1999 2000
Example of Excellent Coating after p g16 year of Inspection
3 Layer PE Coating
Another Example of same PipelineAnother Example of same Pipeline
Example of bad coating after 5 yearsExample of bad coating after 5 years
Reasons – Bad conditions during application – moisture condensation
Another example of bad coating
Reason – NaCl impurity during surface preparation
The main reason was that impuritiesThe main reason was that impurities remained on the shot blasted pipeline
Resulted in the complete disbondment in less than 3 yearsdisbondment in less than 3 years
RemedyIntroduced Phosphate‐Pre‐treatment after the blasting just before sending the pipe forthe blasting just before sending the pipe for
heating and coating Booth
Field Joint Coating
Integrity of a Pipeline to great extent depends upon the Soundness of the FJCdepends upon the Soundness of the FJC
The welding of pipes makes this areaThe welding of pipes makes this area quite vulnerable to corrosion.
Hence selection, application and testing of the FJC still remains a critical area.
Welded pipe after shot blasting
Application of EpoxyPrimer on a Field Joint Prior to Heat Shrink Sleeve
Heating method, whether by torch / InductionDecides the soundness of the FJC
Pipeline Integrity can be achieved by avoiding f ll i f ilfollowing failures
• Use of Coating• Use of Cathodic Protection
External corrosion • Use of Cathodic Protectioncorrosion
• Internal coating• Corrosion inhibitors
Internal corrosion Corrosion inhibitorscorrosion
Oth lik ld tOthers like weld etc.
Coating & Cathodic ProtectionCoating & Cathodic Protection
Cost
Total Cost
Coating
CathodicProtection
0 % 100 %
CP for coated pipelineAnode bed
TR
+ CP Current
TR‐
Monitoring external corrosionInspection of Cross‐country pipeline (OISD‐ 138)
PSP at drain point ‐ FortnightlyPSP at drain point Fortnightly
PSP at test lead points ‐ Quarterly
Pearson survey ‐ Once in three yrs.
CPL Survey ‐ Once in five yrs.
I/J Coupling inspection ‐ Once in year/ p g p y
Soil testing ‐ Once in five yrs.
Above ground piping ‐ Once in a year
Thank youThank you