Technical Program - Schedule
Tuesday February 5Wednesday February 6Thursday February 7
|8:00 - 8:05 AM||Opening Remarks - Dean Jenson, Conference Chair |
|8:05 - 8:35 AM||Keynote Speaker - Brendon Rowen |
|Track 1 - Material Sustainability |
|Track 2 - Pipeline Integrity|
Prabhu Srinivasan & Craig Ball
|Track 3 - Protective Coatings |
Aissa Van Der Veen & Wayne Duncan
|8:45 - 9:15 AM|
Chris Taylor - Overview of Corrosion Management for a Sustainable Future
“Corrosion Management for a Sustainable Future” is a new NACE monograph which is currently in press. The book contains contributions from experts across several fields where corrosion science and engineering are critical to future development. These topics include lightweight alloys for transportation, renewable energy systems such as photovoltaics, maintenance of drinking water infrastructure, trends in corrosion management for the upstream and downstream oil and gas, as well as shifts that may be expected due to projected constraints on resource availability over the coming decades. Other topics considered include green inhibitors and preservation of reinforced concrete structures. In this conference paper we make an overview of opportunities for corrosion engineers in each of these domains.
Chukwuma Onuoha - Identification of Unknown Steel Rods on Buried Pipeline Using Indirect Inspection Method
A pipeline operator was endeavoring to identify locations of numerous unknown heavy steel rods found on top of their buried, coated, and cathodically protected pipeline. They were alerted to the presence of these steel rods during routine pipeline excavations in the area of interest. A subsequent assessment concluded that the rods were capable of causing damage to the coating of the pipeline. Furthermore, the pipeline in question has a higher than normal risk associated with any type of coating damage due to it being difficult to pig and residing in a challenging right-of-way (ROW). The ROW is on a busy road where high resistant pavement, access constraints, and costly city permits create difficulties for performing cathodic protection close interval surveys (CP CIPS), direct current voltage and alternating current voltage gradient coating surveys (DCVG and ACVG). Faced with these hurdles, Alternating Current Current Attenuation (ACCA), Large Standoff Magnetometry (LSM), and a magnetic field sensor (Weld Witcher) were employed to accurately pinpoint the exact locations of these unknown steel rods and allow for efficient extraction.
This paper will substantiate presented arguments using comprehensive case studies discussing classification and prioritization of methodologies, practical experience, and lessons learnt from this unique project.
Maurice Batallas - Internal Coatings for Corrosive Service Pipelines
The use of internal coatings provides the pipeline designer another option for the safer transportation of media including corrosive liquids such as water, contaminant sensitive refined petrochemicals, fuels, and gases among others. Traditionally, pipelines carrying these cargos have been protected by means such as plastic linings, or by coatings applied in a work shop by a mostly manual based process. The development of a manufacturing capability for applying liquid coatings including into larger diameter pipelines in a high production rate process as well as the availability of various options for protecting the internal girth weld or joint areas now makes it more feasible to consider the use of internal coatings for new pipeline projects where such coatings can provide a cost-effective improvement to pipeline integrity. This paper discusses the opportunities for using internal coatings as well as some of the potential challenges related to current coatings standards which may require to be addressed for wider adoption by industry.
|9:15 - 9:45 AM|
Monica Hernandez - Corrosion and Protection Challenges and Opportunities in the Frame of a Circular Economy
The cost of corrosion has long been a debate topic. General awareness at every level of the industry, academia and even some governments, has increased as a result of the efforts to make this a public subject where we can all contribute to search for solutions.
In a fast changing world, it’s imperative that as engineers and scientists, we look at innovative ways to help support the circular economy tendency, oriented to reach “a better life with fewer resources”. Merging concepts like designing for purpose, maintaining with integrity, and decommissioning with a second life in mind are some of the ideas that, if used in conjunction with the adequate management tools, can help industries go in the right path of applying an effective corrosion management system. Challenges to this emerging tendency are widespread and solutions to aid in their minimization also need to be widely discussed and addressed to ensure the right approaches are taken.
This paper shows how profitability can be achieved to increase market value and business, and at the same time helps with being environmentally sustainable; reducing waste and being more efficient. In other words, we must be prepared to move from the era of the unlimited consumption to a new one, where we’re fighting against lost and misuse of materials, supporting the coming development of the humankind. Consequently, people and companies dealing with corrosion science and engineering must be ready for a strengthening of the relevance of the subject and an increase of the importance of their role in the new economy.
Daryl Foley - SAGD Steam Distribution Pipelines Damage Prevention Through Design and Operation
Steam distribution pipelines associated with Cyclic Steam Stimulation (CSS) and Steam Assisted Gravity Drainage (SAGD) have unique risks in terms of mechanical integrity. Operating experience is available as far back as the early 1990’s for SAGD and as early as the 1970’s for CSS. The type of boiler used, steam separation equipment, method of water treatment and source of the boiler feedwater, play a significant role in relation to the operating environment present in a steam distribution pipeline. Other factors are also very important and must be considered. Threats that exist while operating these pipelines require specific knowledge of the operating conditions and process chemistry to effectively understand the damage mechanisms that can be present.
Operating temperatures and pressures make traditional online monitoring difficult and less traditional approaches to monitoring must be used.
Threats are unique and include both internal corrosion and erosion related mechanisms, as well as operational threats such as condensate induced water hammer. All risks must be considered, and the methods of management include a variety of operating departments and competencies. This paper reviews design and operational practices that support effective management of threats to ensure safe operation of steam distribution pipelines.
Gil Rogers - Residual Soluble Salts and Coating Performance – Developing an Algorithm for Determining Salt Contamination Thresholds
Establishing acceptable levels of residual soluble salts prior to applying protective coatings has largely been a matter of judgement on the part of specifiers and coating suppliers who have tended to specify very low levels without a detailed risk analysis. “Lower is better’ has been the mantra.
In a previous paper entitled, “Residual Soluble Salts and Coating Performance – Separating Myth from Reality” the authors questioned the coating industry’s arbitrary approach to establishing acceptable residual levels of soluble salts prior to coating application.
In this paper, the authors’ review the arbitrary nature of the industry’s current practices and introduce the concept of using an algorithmic approach in order to determine an acceptable salt contamination range base on specific conditions on a particular project. The paper weights diverse risk and physical factors that influence the decision and presents an algorithm that can be used widely to establish a more consistent and factual approach to acceptable levels of residual soluble salts prior to coating application.
|9:45 - 10:30 AM||Morning Break|
|10:30 - 11:00 AM|
Gary Coates - Stainless Steel: A Long Lasting and Sustainable Choice
Sustainability has evolved from a minor influence on building design to a global megatrend with the potential to affect every industry. International standards already exist related to sustainable buildings, manufacturing, water management and many other areas. The successful use of alloys in the stainless steel family in corrosive and high temperature applications is well recognized in various industries such as oil and gas, petrochemical, chemical, pharmaceutical, mining, power generation and food. It is increasingly being specified and used in structural applications where safety, resiliency and longevity are required while requiring minimal or no maintenance. Furthermore, the long life comes most often from bare (uncoated) metal. Stainless steel is an indefinitely recyclable material, with high rates of recovery and ability to be made new high quality material. Fully capitalizing on the unique advantages of stainless steel requires understanding of the opportunity and education of customers and decision makers.
Chukwuma Onuoha - Improvements in Direct Assessment Methodologies using an Integrated Approach
Because of the serious consequences of external corrosion and cracks in underground pipelines, external corrosion direct assessment (ECDA), and stress corrosion cracking direct assessment (SCCDA) were developed in an attempt to proactively prevent external corrosion and stress corrosion cracking and ensure the integrity of oil and gas pipelines. These threats are specified in NACE SP0502-2010 and NACE SP0204-2015 for external corrosion and stress corrosion cracking respectively. ECDA and SCCDA inspections are applicable to pipelines that are difficult or impossible to pig or inspect with inline inspection (ILI), as well as piggable pipelines, where it can be used as a supplement to ILI. The indirect inspections of ECDA and SCCDA are proactive since they can detect where external corrosion and stress corrosion cracking are probable.
This paper will show improvements to Direct Assessment (DA) methodology and how advances in indirect inspection techniques would ensure accurate selection of locations most susceptible to external and stress corrosion cracking. This methodology would lead to improvement to overall pipeline integrity while justifying the cost of excavations to explore suspicious indicators. Several case studies showing improvements in indirect inspection analysis from previous ECDA and SCCDA Indirect inspection and digs are presented.
|Dr. Mike O’Donoghue - Intumescent Epoxy Passive Fire Protection in Hot and Cold Climates|
|11:00 - 11:30 AM|
Darcy Pretula - You Zinc You Know Hot Dip Galvanizing
For more than 150 years, hot-dip galvanizing has been used throughout various markets to provide steel with unmatched protection from corrosion. Recent estimates have shown that metallic corrosion costs Canada billions of dollars, however the cost of corrosion is much greater than just financial. Metallic corrosion can lead to waste of natural resources, infrastructure failures and many other indirect costs. Using adequate corrosion protection systems such as hot-dip galvanizing at the start of a project, can significantly reduce this risk.
Hot-dip galvanizing is the process of dipping fabricated steel into a kettle containing molten zinc. While the steel is in the kettle, the iron in the steel metallurgically reacts with the molten zinc to form a tightly-bonded alloy coating that provides superior corrosion protection to steel. Though corrosion resistance is inherent any time galvanizing is used, more specifiers select hot-dip galvanizing for other reasons including lowest initial life-cycle cost, durability, longevity, versatility, sustainability and aesthetics. In addition to learning the benefits of utilizing hot-dip galvanized steel, we will also examine ASTM specifications, design best practices, inspection and preparing the galvanized surface for painting or powder coating.
Daniel Fingas - Remedial Testing and Cathodic Protection Design on a Deep Trenchless Crossing
The ability to adequately monitor and protect long, deep trenchless crossings installed in rock is critical to ongoing safe operation of pipelines. This paper is a case study of a long horizontally directionally drilled crossing that was subject to significant coating damage at installation.
The pipeline was protected by an impressed current system and a test method was developed to estimate the current pick-up along the pipeline from existing rectifiers. Subsequently, a current requirement test was performed to estimate the effectiveness and efficiency of a supplemental groundbed to be installed adjacent to the crossing.
A permanent cathodic protection system including monitoring was designed and installed. Recommendations for identifying this type of deficiency during the construction phase are proposed.
Amal Al-Borno - Discoloration of Fusion Bond Epoxy
The question as to whether discoloration of protective coatings exposed to sever environments should be considered “failure” is debatable. To date no international specification or international standard test procedure has referenced discoloration as a performance measure that should be considered failure of the coating. In this study, Fusion Bond Epoxy (FBE) coating system that discolored severely when exposed to alkaline immersion condition at high temperature was examined. This was done using analytical techniques such as scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) spectroscopy, attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR), differential scanning calorimetry (DSC), pull-off adhesion, and electrochemical impedance spectroscopy (EIS). Results obtained indicated that the exposure resulted in the formation of adhered deposit layer due to the leaching of low molecular weight coating component, a discolored zone underneath which showed chemical deterioration of coating and a remaining unaffected bulk of the coating. Although the adhesion strength and barrier property were not affected, the polymer matrix in the affected zone undergoes severe changes in its surface microstructure, primary chemical structure, and glass transition temperature. This may inflict serious impairment of the coating functional properties and premature failure of the coating in long term exposure.
|11:40 - 11:50 AM||Address from Calgary Mayor - Naheed Nenshi
|11:50 - 12:00 PM||Address from Minister of Service Alberta - Brian Malkinson
|11:30 - 1:00 PM||Lunch Break|
|Track 1 - Material Sustainability |
|Track 2 - Pipeline Integrity |
Prabhu Srinivasan & Craig Ball
|Track 3 - Asset Integrity Facilities
Monica Hernandez & Monica Santander
|1:00 - 1:30 PM|
Elaine Bowman - IMPACT PLUS: How the Corrosion Industry is Revolutionizing Corrosion Management
NACE International initiated the International Measures of Prevention, Application, and Economics of Corrosion Technologies (IMPACT) study to examine the current role of corrosion management in industry and government and to establish best practices.
The global cost of corrosion is estimated to be US$2.5 trillion, which is equivalent to 3.4% of the global Gross Domestic Product (GDP) (2013). By using available corrosion control practices, it is estimated that savings of between 15 and 35% of the cost of corrosion could be realized; i.e., between US$375 and $875 billion annually on a global basis, an astronomical savings. In addition, these costs typically do not include individual safety or environmental consequences. The high cost of corrosion has been known for years; Uhlig performed a comprehensive study in 1949 that revealed a cost of corrosion equivalent to 2.5% of the U.S. GDP.
Colin McGovern - A Comprehensive Pipeline Risk Management Model
Traditionally, Upstream Integrity/Corrosion Teams (or specialized service providers) develop “risk” assessment models used to evaluate pipeline risk. These models are typically focused on the likelihood assessment of internal corrosion and may provide a cursory evaluation of consequence. The models are rarely directly aligned to Corporate (senior-management endorsed) Risk Criteria, often lack both a rigorous threat and consequence-based review of mitigations & controls and a risk accountability process. These limitations prevent existing “risk” assessment models from fully influencing pipeline risk management decisions and reducing loss of containment events.
Canadian Natural Resources Limited has developed a comprehensive Pipeline Risk Management Process that is directly linked to the Corporate Risk Criteria, assesses the likelihood related to all foreseeable threats, assesses consequence based on commodity, sensitive receptors and potential for adverse effect, requires validation of mitigations & controls, and incorporates a senior management risk acceptance process. The deployment of this process has resulted in a significant step-change in the engagement of key stakeholders, an increased understanding and focus on pipeline risk management and a reduction in high consequence pipeline failures.
This paper summarizes the pipeline risk assessment models and the full life-cycle process by which Canadian Natural manages risk on our inventory of over 50,000 operating pipelines (> 70,000 kms).
Irina Shchegoleva - A Review of Potassium Acetate Corrosivity in Oil Refin
A refinery had a failure in the line transporting water from the sump system to the black water tank. A potassium acetate-based deicer was added during the winter several months before the failure. We sought to determine whether the potassium acetate (KOAc) under the conditions used was contributing to corrosion, and if so, in which way. An experiment was designed to see how KOAc behaves in both the vapor and liquid phases. Varying oxygen levels, heat, and the application of a corrosion inhibitor were explored.
The results indicate that KOAc is not corrosive in the vapor phase when there is no oxygen in the system, and provides corrosion protection in the water phase. However, KOAc degrades as the concentration of oxygen increases. A greater solution concentration of acetate has been linked to a greater corrosion rate in the vapor phase when oxygen is present. KOAc should not be used under conditions in which oxygen ingress is possible. The addition of heat exacerbates corrosion concerns. Regular corrosion inhibitors designed to protect pipelines from CO2 corrosion were not effective in the tested conditions.
|1:30 - 2:00 PM|
Jim Chmilar - NACE International Standards Development: Behind the Scenes
The NACE International Technical Coordination Committee (TCC) Advisory Committee on Operations (ACO) has responsibility for the Standards Publication Manual(TCPM) which covers the development and maintenance of NACE standards. The presentation will provide an overview of the Standards development process and follow the process of a report which originated with a group of Calgary Section members back in 1988 and today the report is going for its second re-affirmation by Specific Technology Group (STG) 35 and Task Group (TG) 289. The report 10A392 title is “Effectiveness of Cathodic Protection on Thermally Insulated Underground Metallic Structures” was actually included as Appendix “O” of the May 2016 US DOT PHMSA Failure Investigation Report Plains Pipeline, LP. Line 901 Crude Oil Release, May 19, 2015 Santa Barbara County, California. Presented will be a review of the recent review by Task Group 020 of TM0497-2012 which has just been published as TM0497-2018. Upcoming is a review of SP0169-2013 and NACE members NEED TO BE INVOLVED with the circular Standards process.
Jorge Paez - Deep Dive Methodology for the Evaluation of High Profile Pipelines in the Upstream Oil and Gas Industry
In 2010, Talisman Energy (now Repsol Oil and Gas Canada Inc. – ROGCI), published a paper outlining its recently developed methodology to conduct pipeline risk assessments (NACE NAWC 2010). Since then, ROGCI has been annually generating a report where the top 20 high consequence pipelines are identified. Assessment steps include review of failure probability, integrity threats and mitigation actions. The resulting report is then presented to management for review.
Understanding where the high-profile pipelines are located and what mitigation measures are in place is important, but it is also half of the equation. It is important to understand if there are unknowns in the threat identification process and in the case of a release. It is also critical to understand if the organization is ready to respond to a release and minimize impact.
This paper describes ROGCI’s “Deep Dive” methodology developed to evaluate high profile pipelines. The developed methodology combines principles of process safety and pipeline integrity with the idea of better identifying threats and consequences to finally establish the effectiveness of all available safeguards. A Bow Tie approach was used as the basis of the evaluation process.
Kevin Sunderman - Above Grade Storage Tank Bottom Corrosion Preven
Corrosion damage of above grade storage tank bottoms (AST) due to soil side corrosion remains an ongoing concern for owner/operators. An effective corrosion management plan (CMP) and implementation of this CMP throughout the design, installation and operational lifecycle of an AST is a necessity for preserving the structural integrity of this vital asset.
This paper outlines causes of AST soil side corrosion and corrosion prevention strategies to incorporate into a CMP for the prevention/management of this soil side corrosion. Key strategies that will be covered will include tank base construction method, base materials, water management, cathodic protection, supplemental corrosion protection measures (when to use), and maintenance. Included will be lessons learned from a constructability perspective and key items to include in an Inspection and Testing Plan (ITP) for utilization during the installation phase of an AST.
|2:00 - 2:45 PM||Afternoon Break|
|2:45 - 3:15 PM||Material Sustainability Forum |
Connor Blake & Robin Eastman - An Investigation of ILI Methods and a New Integrity Screening Solution
An investigation of available ILI methods reveals that although these methods are accurate and technologically advanced, they are costly and often require that a pipe be dug up and cut open to provide access for the ILI tool. These economic limitations prevent these methods from being easily applicable to all segments of the pipeline marketplace; most notably small diameter flow lines.
A new integrity screening method has been developed that allows for cost-effective integrity monitoring of small diameter flow lines and internally coated lines where MFL and other similar technologies are ineffective or cannot be used.
The solution is a free-swim, visual pipe inspection pig. This tool navigates conventionally un-inspectable geometries including back-to-back schedule 80, 90-degree elbow fittings in NPS 03 and 04. The tool utilizes existing pigging infrastructure and can inspect entire line lengths from trap to trap. This technology allows pipeline operators to inspect lines that previously could not be inspected by ILI tools due to geometry, economics, or access. This tool also creates an option to inspect upstream lines for uneconomic wells that until now could not cover the cost of inspection. This allows for more lines to be inspected in a given integrity program, generating a more accurate picture of overall field integrity.
Frank Gareau - High-Temperature Degradation Mechanisms of 304H which Resulted in Reactor Failure
A leak occurred in an Oleflex reactor that resulted in a fire. Circumferential cracks developed in the reactor shell and through inspection methods, cracks were found in similar locations in different reactors of this type. The failure was attributed to several contributing factors including a combination of the reactor design, thermal issues, and high-temperature material degradation.
An extensive NDE inspection program, and fitness for service assessment in combination with a destructive failure analysis allowed to evaluate high-temperature degradation mechanisms and to establish their contribution to the failure.
Numerous degradation mechanisms and ways they were addressed by inspection and evaluated in the root cause analysis (RCA) will be discussed. These degradation mechanisms include sensitization, sigma-phase embrittlement, hydrogen embrittlement, high temperature hydrogen attack, blistering, HIC and SOHIC, creep, welding stress and reheat cracking, stress corrosion cracking, and high-temperature oxidation.
Remediation actions included different approaches to repair the reactor and modifications to the design.
Key words: stainless steel, high-temperature degradation, failure analysis, inspection, repair.
|3:15 - 3:45 PM|
Cory Wargacki - Advancements of an Integrity Management Program by Breaking the Boundaries of Crack Depth Sizing
Inline inspection (ILI) is a fundamental stage of an integrity management program (IMP). The accuracy of the results will directly influence the operational reliability of pipelines, as tool tolerances and uncertainties must be considered for an accurate integrity assessment.
ILI crack inspections have continuously been improving the accuracy of depth sizing results. Depth sizing with conventional pulse-echo technology delivers an indirect measurement of a feature depth. The first ILI inspections used a range format to report the feature depths; and with continuous research, absolute depth measurements were achieved.
The introduction of absolute depth sizing is state of the art in the industry. Nevertheless, for these methodologies, there is still an uncertainty of features with a >4 mm (>0.16 in) depth. In any IMP, the depth of the feature is important as deep features represent a higher risk of leak or rupture, specifically for cases with deep features >4 mm (>0.16 in) enhanced sizing (ES) has the capability to size cracks for the entire wall thickness (WT) range.
ES provides higher resolution data to integrity engineers. Changes in crack depth generate different estimations of failure pressure. The comparison of the results between the three methodologies allows for the observance of change in pressure estimated with a trend towards greater accuracy. These innovations of the ILI service have an ultimate goal to improve the measurement and increase the accuracy of detectable cracks.
Michael Sheilan - Iron Sulphide-Friend or Foe
In sour gas production there are two primary corrosion causing species: hydrogen sulphide (H2S) and carbon dioxide (CO2). The corrosion products that form from the reaction of these gases with steel in the presence of water can provide a clue as to the formation mechanism, the severity of the potential corrosive environment and the degree to which the corrosion will affect operation of an amine unit.
In any amine system, corrosion of piping and equipment is one of the worst of the potential problems an operator or engineer can encounter. Amine plants treating gas containing H2S will have iron sulphides in the system. Are iron sulphides a good thing? When do they help and when do they hinder? This paper will attempt to clarify the pros and cons of iron sulphides present in an amine system.
|8:00 - 8:30 AM||Keynote Speaker - Jeff Didas, NACE President |
|Track 1 - Corrosion Mechanisms and Modelling |
Frank Hornsby & Colin McGovern
|Track 2 - Pipeline Integrity|
Laura Cardenas & Craig Ball
|Track 3 - Chemical Inhibition |
Jorge Paez & Neil Park
|8:45 - 9:15 AM|
Mark Woynarowich - Optimization of Pipeline Field Inspections using a Mobile Inspection Technique
Pipeline operators have been concerned about the quality of field data and its association to assets, resulting from illegibility, omission of critical information, inconsistent reports and inputs from field inspections using traditional methods (paper forms, spreadsheets or email). Typically, the records are sporadic and not available to easily integrate into corporate repositories. This makes it difficult for different business units to access common information and optimize asset management to assist with critical decision making and planning.
Using a mobile device equipped with the inspection app will support pipeline operators with efficient data collection techniques to help eliminate the problem of data quality, availability and usability. The mobile inspection app is hosted in a geospatial environment to provide accurate geographical location of inspection and maintenance activities. This app features: customized forms for various field inspection activities, automatic data transfer capability and integration into pipeline integrity management systems to ensure ongoing reliability and effective compliance management.
This app has received positive market feedback from over 50+ users actively using the app for field inspections, monitoring or mitigation capture. This innovation provides a solution to improve the accuracy and quality of inspection data required for safe operations of pipeline systems.
Harry Grover - Comparison of a Corrosion Inhibitor Micelle Monitoring Approach with Traditional Residual Monitoring Approaches
Corrosion inhibitor micelle monitoring is an alternative option to traditional corrosion inhibitor residual tests. Micelles are nanoscale aggregates of inhibitor which form at the critical micelle concentration. Here we review one micelle monitoring approach and commonly used Dye Transfer Methods, based on formation of a colorimetric-complex. Differences in the technical principles and format of results are discussed, together with potential interferences for each method.
Case studies, summarising the on-site use of the micelle monitoring technology will be presented, from a variety of assets and fluid types including data captured from high water-cut production systems and low water-cut transportation systems.
|9:15 - 9:45 AM|
Ameeq Farooq - Effect of PWHT on the Electrochemical Behavior of API X-65 Welded Pipeline in Bicarbonates Solutions
API X–65 steel is mainly used as material of choice for high pressure transmission oil and gas pipelines. To join long section of pipelines, welding is the main procedure adopted to overlay large network for oil and gas transport from one location to another. The aim of this research work is to study the effect of post weld heat treatment (PWHT) on Gas Tungsten Arc Welded (GTAW) API–X65 steel pipeline sections. The PWHT was carried out at 620 ± 5oC for 30 min followed by furnace cool to room temperature. The microstructure in the weld zone of as welded section contained both primary and secondary widmansttaten ferrite formed at the allotriomorphic ferrite colonies. This microstructural features were affiliated with the non–equilibrium cooling after welding thermal excursion. During PWHT, this was modified to coarse polygonal shape ferritic grains. The effect of microstructural variation on the electrochemical behavior was estimated from the Potentiodynamic polarization and Electrochemical Impedance Spectroscopy analyses in 0.1 and 0.2 M NaHCO3 solution. In 0.1 M solution, the open circuit potential (OCP) of HAZ was shifted from 770mV to 517mV (vs. SCE) after heat treatment and considerable decrease in pre–passive (active) and passive current density of Base Metal (BM), Heat Affected Zone (HAZ) and Weld Zone (WZ) was attributed to the coarse grain structure after PWHT. The increase in NaHCO3 concentration from 0.1 to 0.2 M also decrease the pre–passive anodic current possibly due to the enhanced stability of Fe(OH)2 surface film. In comparison it is suggested that both increase in HCO3–¬ concentration and PWHT could significantly reduce the dissolution tendency of steel. This may be attributed to the formation of composite, Fe(OH)2 and FeCO3 surface film and/or to the diffusion controlled process by the soluble Fe(CO3)22– species. The beneficial effect of PWHT is also evident from the impedance spectroscopy which also validated the increase in CPEdl 307S.sn from 838S.sn and increase in Rct from 1.257 kΩ–cm2 to 3.493 kΩ–cm2 of HAZ.
Stephen Westwood - Use of NDE Data in Correlation with MFL Data to refine Neural Network Sizing Algorithms
In recent years pipeline operators are routinely using advanced Non-Destructive Examination techniques such as laser scans or automatic ultrasonic wall thickness measurements to characterize external corrosion features. The increased accuracy from these measurements allow Pipeline inspection companies to put more faith in the information provided by the pipeline operators. This is because the error from a laser scan or UT is much smaller than the error from a conventional pit gauge. The correlation of this NDE information to In-Line Inspection (ILI) data allows unity plots to be generated to determine the tool performance in the first instance. After this point, a decision can then be made whether to re-train the model on the NDE data to allow a better sizing performance. In this paper we describe the process and demonstrate the benefits to pipeline operators on challenging corrosion features.
Jody Hoshowski - Laboratory Evaluation of Alternate Liquid H2S Scavenger Chemistries
Sulfur compounds can be found in oilfield production with H2S tending to be the most predominant form. The removal of H2S reduces the corrosion, toxicity, facilitates phase separation, and increases the value of the hydrocarbon products. Sulfide corrosion usually appears as pitting on carbon steel and can involve hydrogen-induced cracking (HIC) or sulfide stress cracking (SSC).
Monoethanol amine (MEA) triazine is the most commonly used liquid H2S scavenger in oilfield applications primarily due to its cost performance benefit. Although effective in a number of applications, MEA triazine’s relatively high pH; insoluble reaction products; and relatively low thermal stability can create operational issues or limit its range of applicability.
Alternate chemistries have been evaluated in the laboratory to determine if such effects can be minimized or eliminated without compromising on performance. The work conducted focuses on exposing liquid scavenger products to a constant stream of H2S and CO2 at a specific temperature and comparing the resulting uptake to MEA triazine under the same conditions, by monitoring the composition of the downstream gas.
|9:45 - 10:30 AM||Morning Break|
|10:30 - 11:00 AM|
Abigail Amu - Using Multiphase Flow Modelling to Improve Pipeline Integrity Decision Making and Risk Assessment
During this time in the oil and gas industry, it is important to optimize mitigation and maintenance budgets in order to identify, target, and prioritize assets that require the most attention while at the same time responsibly identifying which assets could require less rigorous solutions. It is suggested that by utilizing a multiphase flow model and leveraging available production, analysis and pipeline network information, more informed decisions can be made with respect to resource allocation and pipeline risk assessment.
Specifically, identifying sensitive regions and position (top or bottom of line) of corrosion within a pipeline and evaluating the effectiveness or suitability of currently prescribed mitigation methods based on a more intimate knowledge of the flow regimes, phase velocities, and pressure and temperature conditions within individual pipelines and the connected network enables further optimization of pipeline integrity program effectiveness and cost. Applications with respect to coupon/probe location placement, inline inspection candidate selection and batch/continuous chemical program prescriptions are discussed.
Luc Simon - In-line Inspection Experience with Lined Upstream Pipelines
An internal corrosion failure occurred in one of Shell Canada’s (Shell) high density polyethylene (HDPE) lined sour gas pipelines in 2007. That failure led Shell to shut in all of its lined sour gas pipelines until the integrity of each could be verified and the internal corrosion mechanism was under control. The presence of a non-metallic liner within the pipelines made full in-line inspections (ILI) challenging. The removal and re-installation of liners had been the typical way to complete such ILI with magnetic flux leakage (MFL) smart pigs, but this was not practical in this case. Existing remote field testing (RFT) ILI tools were available and had been used by industry to inspect unlined pipelines, reinforced-concrete and cement mortar lined (CML) pipelines. It was this technology that was chosen to inspect the lined sour gas pipelines with the liners in place. The use of repeat RFT ILI since 2008 has provided verification of integrity and confirmed the pre-existing internal corrosion mechanism is now under control. The inspection success with HDPE lined pipelines led Shell to use the same technology to recently inspect a 28yr old CML produced water pipeline. External corrosion at disbonded coating locations was confirmed active on the pipeline. The RFT ILI allowed Shell to schedule repairs and continue use of the CML pipeline.
The ability to ILI existing lined pipelines without removing the liners is a tremendous advantage to Shell. RFT ILI of lined pipelines was novel in the past but is now considered a normal practice. This paper summarizes the experience and shares the learnings of the successful application of RFT ILI technology, which became an important part of Shell’s pipeline integrity management program.
Pierre Blais - Sulphur in Upstream Oilfield Production -The Good, the Bad and the Ugly
Sour systems can be benign, mildly corrosive or aggressive. Published lab results often demonstrate how H2S serves to inhibit general corrosion in the presence of CO2.1 As well, field surveys show many pipelines carrying sour fluids operate for years with no signs of corrosion while others fail rapidly, usually from localized corrosion.2, 3, 4 A key chemical factor that discriminates between these two extremes is the absence or presence of active sulfur species such as elemental sulfur (possibly dissolved in the hydrocarbon phase), sulfanes and ionic polysulfides. Corrosion mitigation programs must account for the prevailing chemistry in the produced fluids. Producers must determine the sulfur-based chemical compositions of their fluids to do accurate risk assessments and to select appropriate mitigation programs. Lab tests used to select inhibitors must accurately simulate producing conditions to get meaningful data. A basic chemical model describing the relationship between these species, their distribution between two or three phases and their participation in corrosion mechanisms is presented along with test results showing associated corrosion and how it can be mitigated.
|11:00 - 11:30 AM|
Carlos Melo - Use and Misuse of Internal Corrosion Models for Pipeline Integrity
Several integrity management methods are available to reduce the threat of internal corrosion in pipeline systems. They include 5-M methodology, Internal Corrosion Direct Assessment (ICDA), risk-based inspection (RBI), and inline inspection (ILI). In all these integrity management approaches internal corrosion models are applied; in some approaches such as 5-M methodology and ICDA, the application of internal localized corrosion models is explicit. In some approaches such as RBI and ILI, the application of internal localized corrosion models is not explicit, but internal corrosion models are used in the decision making of when and where to carry out the activities. In order to evaluate, select and apply internal corrosion models recently two NACE technical reports have been published:
• NACE Technical Report 21413, “Prediction on Internal Corrosion in Oilfield Systems from System Conditions” (2017)
• NACE Technical Report 21410, “Selection of Pipeline Flow and Corrosion Models” (2015).
• Discusses the logical steps to evaluate, select and use internal corrosion models
• Presents case studies in which internal localized corrosion models have been successfully used in conjunction with other integrity assessment methods such as ILI and RBI
• Deliberates the responsibilities of regulators, users, model developers, and industry to avoid misuse of internal localized corrosion models.
Scott McKelvey - A Big Data Approach to Cathodic Protection: Opportunities and Pitfalls
Pipeline integrity is embracing the technologies that have been produced by the Big Data revolution. Database access, machine learning algorithms, and analytics tools are no longer the domain of researchers and IT experts, and can be easily deployed to improve our use of pipeline integrity data.
We will discuss the data governance requirements borrowed from Big Data as applied to CP, a case study involving CP measurements with differing levels of data structure, and rules and lessons learned related to the Big Data approach.
Jennifer Dickason - Field Application of a Non-Acidic Chemistry for Iron Sulphide Dissolution and Corrosion Mitigation
The formation of iron sulfide in oil and gas production can cause both flow restrictions and corrosion problems by either plugging equipment or causing under-deposit corrosion, respectfully. Iron sulfide can be formed by the reaction of naturally occurring dissolved iron with sour fluids or by the corrosion of steel in sour environments. Current methods to rectify the flow assurance issues range from using acid to dissolve the iron sulfide to application of Tetrakis(hydroxymethyl) Phosphonium Sulfate (THPS) as an iron chelator. The use of acid, while effective, could be detrimental to production equipment. A new chemistry developed for iron sulfide dissolution has proven to be more effective at lower dosage rates in comparison to those for THPS. This presentation is a continuation of work presented at NAWC 2017, which focused on a combination cleaner/corrosion inhibitor. The addition of the new chemistry to this family of chemicals further enhances the ability to clean and protect systems. This presentation will discuss the background of the novel chemistry and describe a few application case histories.
|11:30 - 1:00 PM||Lunch Break|
|Track 1 - Corrosion Mechanisms and Modelling |
Frank Hornsby & Colin McGovern
|Track 2 - Cathodic Protection |
Bala Ganapathy & Spencer Easthope
|Track 3 - Chemical Inhibition
Jorge Paez & Neil Park
|1:00 - 1:30 PM|
Ibrahim Gadala - Non-Linear Finite Element Simulations of Corrosion Defect Growth underneath Disbonded Coatings of Buried Pipelines
A nonlinear finite element model simulating the growth of corrosion defects in crevices existing underneath disbonded coatings of buried pipelines is presented in this paper. Potential distributions in the trapped water beneath pipeline coating disbondments are modeled in conjunction with reaction kinetics on the corroding exposed steel surface using a moving boundary mesh. With model inputs based on results extracted from representative electrochemical experiments, it is found that temperature dependencies of reaction kinetics, within the 25 to 50 ºC range, do not strongly affect final corrosion defect geometries after 3-year simulation periods. Conversely, cathodic protection (CP) levels within the -0.75 to -1 VSCE range and pH dependencies within the near-neutral pH range (6.7 – 8.5) strongly govern depth profiles caused by corrosion, reaching a maximum of approximately 3 mm into the pipeline wall. The simulations show that a 0.25 V amplification of CP potential combined with a 0.5 mm widening in disbondment opening size can reduce defect penetration in the pipeline wall by almost 30%. This paper is part of an overall work which integrates a corrosion model with a stress analysis model for pipeline integrity analysis using numerical methods.
Jeffrey Didas - AC Interference - AC Mitigation - AC Corrosion: A Discussion of the Basics
A discussion of the basics of AC Interference, AC Mitigation and AC Corrosion. There are an increasing number of pipelines being installed in AC power corridors and AC powerlines being installed down pipeline Rights of Way. A lot of misconceptions and myths exist about the effects of pipelines and powerlines sharing the same corridor exist. This paper will discuss the basics of AC interference and methods of mitigation as well as the AC corrosion phenomena. The misconceptions and myths will be addressed and explained.
Mark Zazulak - Volatile Corrosion Inhibitors Applied to Soil Side of In-Service Storage Tank
Controlling corrosion of above ground storage tank (AST) floors is a challenge with limited methods available beyond cathodic protection (CP). Re-establishing protection on CP systems that are depleted or inadequate is an expensive and intractable challenge, particularly under in-service conditions and further exacerbated by small clearances between secondary containment liners and the tank bottom.
This paper describes the application of volatile corrosion inhibitors to the soil-side of an aboveground storage tank while in service. Additional aspects of the project are the use of a low-risk vacuum excavation technique to insert perforated piping beneath the tank floor and secondary containment liner; a berm foundation composed of gravel with a thin layer of sand between the gravel and the tank floor.
An assessment of success is to be provided by ongoing corrosion rate monitoring via electrical resistance (ER) corrosion rate probes.
|1:30 - 2:00 PM|
Mohammad Reza Haghgoo - Numerical Prediction of Mass Transfer Controlled Corrosion inside an Elbow
In practical flow systems it is often found that corrosion is a mass-transfer-controlled process. The rate of mass transfer in straight pipelines can be correlated entirely in terms of mean flow properties. However, in more complex geometries, e.g. curved channels and elbows, the mass transfer rate is significantly influenced by the local flow properties, particularly the turbulence intensity. The effect of mean streamline curvature on the mean flow structure and turbulent transport is known to be significant and thus should be included in numerical models.
In this study the mass transfer rate in aqueous, turbulent flow through an elbow is numerically predicted using a Reynolds-Averaged Navier-Stokes (RANS) formulation with associated turbulence models. The predicted rates are compared with experimental data. In the case of high Schmidt number fluids, the mass transfer boundary layer is entirely located in the viscous sublayer of the hydrodynamic boundary layer. Therefore, to capture the mass transfer boundary layer the flow must be resolved throughout the viscous sublayer region. It is shown that even low levels of turbulence in the near-wall region have a significant effect on the overall wall-mass transport.
Chukwuma Onuoha - Predicted and Actual Dig Outcome of ECDA on Multiple Buried Onshore Pipelines
Recent advances in External Corrosion Direct Assessment (ECDA) methodologies have restored confidence in pipeline operators who rely on this approach to assess the integrity of their pipeline assets. This is partially because of improvements in ECDA technologies to integrate multiple inspection techniques into one integrated pipeline inspection technique that ensures improvement in reliability while reducing the time and cost to collect data, and to process, analyze and report inspection results.
These advances have also led to improvements in the interpretation of indirect inspection data such that direct examination locations are accurately selected to pinpoint and address locations at which external corrosion activity has occurred, is occurring, or may occur. Successfully identifying regions for excavation is vital as it substantially reduces costs by avoiding unnecessary digs and downtime due to potential failures.
This paper will show how precise selection of direct examination location can reduce unnecessary and costly excavations for pipeline operators while making sure that most susceptible locations are addressed to prevent future wall loss from external corrosion. In addition, statistical analysis drawn from recent projects, that compare the predicted and outcome of several ECDA digs and lesson learnt will be presented to strongly demonstrate improvements in ECDA methodologies.
Jennifer Sargent - Synergistic Effect of Biocide and Corrosion Inhibitor in Mitigation of MIC in Wet Parked Crude Oil
Crude oil transmission pipelines are sometimes laid up with the oil (wet parking) due to downstream operational issues, new construction, or low crude volumes. Often such layups occur with feeder and facility lines that are unpiggable and can last several months to years. Solids settle in the static oil encouraging the growth of microorganisms and biofilms leading to microbiologically influenced corrosion (MIC). A laboratory study was conducted to (i) simulate long term MIC in oil parked pipelines using sludge from pipeline with MIC activity and (ii) observe the impact of biocide, corrosion inhibitor, and a combined biocide-corrosion inhibitor treatment. These samples were incubated up to six months with uniformly-sized carbon steel beads. Corrosion assays (by weight loss), optical microscopy, and 16S rRNA gene sequencing (microbial community composition) were conducted at the end of the experiment. These experiments revealed that a combined biocide-corrosion inhibitor treatment is was the most effective for preventing MIC in oil parked pipelines.
|2:00 - 2:45 PM||Afternoon Break|
|2:45 - 3:15 PM|
Ayodele Okunola - Understanding the Corrosion Mechanisms in a Thermal In-Situ Oil Sands Emulsion Pipeline
For thermal in-situ oil sands production, conventional understanding expects that an emulsion pipeline remains essentially oil-wet. Ideally, an oil coating distributed on the pipe by the produced water-in-oil emulsion from a well pad is expected to give the needed corrosion protection for the operating life of the pipeline. Practically however, there are conditions under which this ideal scenario becomes no longer feasible, even for low API gravity heavy oil. These parameters affecting protection include but are not limited to water cut, well pad processing, steam cycle phenomena, reservoir characteristics, pipeline operating temperature, partitioning characteristics of the acid gases and their effects on water chemistry and passivation as well as other field operational practices.
From the experience of two case histories at a thermal in-situ oil sands project, this paper elaborates on many of the field parameters and how they influence the integrity of pipeline infrastructure by studying the various corrosion phenomena at play. Corrosion mitigation recommendations for these pipelines will also be presented.
Peter Haas - Internal Corrosion Transfer - A Predictive Model
Accelerated internal corrosion can occur at electrical isolators on piping due to cathodic protection. This form of corrosion is commonly referred to as ‘Internal current transfer’ (ICT). ICT is the only known internal corrosion mechanism caused specifically by applying cathodic protection to the external pipe surface. Case studies are presented that describe how to recognize ICT and the methods used to reduce corrosion due to ICT. A hypothetical model describing ICT is presented. The model is based on an equivalent electrical circuit and it can be used to estimate corrosion rates and the effectiveness of various mitigation methods. The model considers fluid resistivity, surface resistance, the level of applied cathodic protection, dimensions of the pipe and isolator and the resistance of the unprotected structure to earth.
Sherman Kung - Development of a New Oil Soluble and Water Dispersible High Temperature Corrosion Inhibitor
Finding suitable corrosion inhibitors for the mitigation of corrosion of carbon steel in oil and gas production is increasingly difficult for fields with high temperature conditions. Additionally, laboratory evaluation of corrosion inhibitors at high temperature is a challenge itself. A series of laboratory test methods at high temperature were conducted to elucidate the factors which affect laboratory corrosion inhibitor performance in high temperature conditions. In this paper we report the development of a new oil soluble and water dispersible corrosion inhibitor that works well at 200°C. The thermal stability data and performance of the corrosion inhibitor under sweet and sour conditions were examined. For these studies, corrosion measurements in stirred autoclaves were performed by weight loss measurement. Surface morphology of the coupons was evaluated by optical microscope.
|3:15 - 3:45 PM|
Alex Tatarov - Different Failure Modes of Composite Pipelines Outside of Connections and Preventive Actions
Non-metallic pipelines are often selected as alternative to steel pipelines. They are relatively new and experience failure modes that are often different compared to steel pipelines. A lack of understanding of specific properties of non-metallic pipelines results in numerous failures. The presentation provides an overview of the different modes of failure in composite pipelines. It is based on actual case studies of field pipeline failures over the past 20 years.
Numerous contributing factors will be discussed: manufacturing defects, chemical incompatibility, construction and installation practices, connection issues, geotechnical issues, pipeline geometry, pressure variations, temperature, liquid hammer, water and gas diffusion, wildlife interference, decompression, ice formation, etc.
Possible remediation actions include: improving construction practices, adjusting operating procedures, pressure control, considering all load cases at design stage, updating operating manuals to reflect composite pipelines.
Improvements in the pipeline code CSA Z662 will contribute to prevention of these failures in the future.
Daniel Fingas - The Lost Art of Telluric Compensation
Techniques for telluric compensation of close-interval potential survey (CIPS) data have been known and used in the pipeline industry for many years. However, the effectiveness of telluric compensation performed during periods of significant geomagnetic activity has resulted in data validity being questioned. In particular cases, survey crews have refrained from data collection during periods of high telluric activity at operators’ request. This paper reviews the theory and basic techniques for telluric compensation.
The value of telluric compensation is discussed with reference to the results of a recent survey in Northern Alberta that was subject to significant telluric effects. The practical benefits are described, including reduced field exposure time, reduced time to complete surveys, and increased data reliability. Challenges of using telluric compensation are also described, and recommendations are made for applying effective telluric compensation to future surveys.
Irina Shchegoleva - Effect of Corrosion Inhibitors on the Degradation of Sulfinol D in Gas Processing Plant
It was suspected that carried-over upstream pipeline corrosion inhibitors can cause degradation of the Sulfinol-D solution in a gas processing plant. Two corrosion inhibitors were tested with Sulfinol-D in high pressure high temperature (HPHT) autoclaves to simulate the degradation over heating and cooling cycles. The degradation products were quantified using standard analytical methods. The results indicate that both corrosion inhibitors prevent the formation of HPMO, sulfates, and thiosulfates. However, the contamination with product A resulted in a small increase in MIPA (mono-isopropanol amine) (by 10.3%) and a large increase in acetic acid (by 212%), confirming the hypothesis that this corrosion inhibitor accelerates Sulfinol-D degradation.
Two parameters show that corrosion inhibitor B is more protective in terms of degradation of Sulfinol-D: a notably smaller amount of MIPA was formed (7.3% decrease vs. degraded pure Sulfinol D), and increase in acetate formation was only 57%.
|Track 1 - Downhole Corrosion |
Trent Pehlke & Phil Stemler
|Track 2 - Civil/Infrastructure|
Joanna Line & Dennis Zadery
|MIC Forum |
John Wolodko & Rick Eckert
|8:45 - 9:15 AM|
Valerie Wilson - Well Integrity and its Impact on Corrosion Control in Oil and Gas Wells
Well integrity is a practice to be applied over the entire lifecycle of the well, from Basis of Design through Abandonment. The proper development and implementation of a Well Integrity Management System (WIMS) over the life of the asset will reduce risk and capex spending, while increasing productivity and safety.
An important part of an operators WIMS is a Corrosion Control Program. Well Integrity and corrosion management programs are critical for oil and gas companies to assure safety and reliability. The costs associated with a corrosion control program are low in comparison to the costs of uncontrolled corrosion which can lead to the replacement of equipment, loss of production due to downtime, contamination of subsurface formations, blowouts and well abandonment due to casing leaks, and many more potential problems.
This paper will discuss several of the corrosion prevention options, which allow operators to be proactive rather than reactive. It will also review a case study and provide an overview of corrosion model types.
Gang Li - Corrosion Prediction with a 3D Model Utilizing Meteorological Data and Properties of Site-Extracted Rebar and Concrete
In this research, the corrosion of rebar in an existing arch bridge section was modelled. Historical environmental and exposure conditions were used to determine the moisture content, chloride ion concentration and carbonation in the concrete. Then the corrosion rate was calculated by correlating measured pore solution composition of cored concrete with electrochemical corrosion measurements of extracted rebar.
The simulation results for the past 100 years of service correlate very nicely with the current condition of the arch, where the greatest amount of corrosion was predicted to occur on the upper layer of longitudinal rebars in the vicinity of the most exposed side of the arch, and the highest corrosion damage (0.1—0.2 mm thickness loss) was found on that rebar near the columns. The rebars in vertical columns and arch sheltered areas have an insignificant corrosion damage due to limited exposure to moisture. It is concluded that a combination of carbonation and chloride ingress accelerates corrosion rates of the rebar. Ineffective sheltering from the rain or more rain water retention on the arch facilitates this penetration and leads to higher corrosion rates.
|9:15 - 9:45 AM|
Chris Harper - Hydrogen Sulphide Fugacity & Enhancement Workflows
The application of H2S partial pressure for providing metallurgy application limits within industrial standards has many challenges, and at a fixed partial pressure, fugacity may vary significantly depending upon fluid compositions and conditions. As Sulphide Stress Cracking requires the presence of an aqueous film in which sulphide-iron reactions can occur, it is postulated that the fugacity of H2S within that film, is a more accurate consideration of metallurgical failure risk than the equilibrium partial pressure for that specific condition.
In paper SPE-179921-MS (1) we discussed the development and application of workflows for determining the risk of sulphide stress cracking on Chevron’s Alba field in the North Sea. This paper discusses how improvements to the understanding of how fugacity and partial pressure relate across a range of conditions and compositions and how this might be applied to the limits set out in NACE MR0175- ISO 15156 and in individual operator material specification guidelines.
The current paper seeks to summarise/simplify previously published workflows and provide additional workflows which will provide a better understanding of the risks during shut-in conditions, the effects of lift gas, effects of topside process operations, from degassing, dewatering, commingling, recycled fluids and typical chemical scavenger applications.
The above is achieved, as described in paper SPE-179921-MS, through the utilisation of several linked multi-iterative equation of state (EOS) (2) and electrolyte modelling (3) processes in a mass balance framework. However, complexity is increased through the incorporation of density profiles for shut-in conditions which utilise specific well and reservoir parameters along with water vapour loading calculations for produced gas and lift gas.
The results of such workflows have provided value in providing both material selection and assessments of current material failure risks with a higher degree of confidence.
Justin Hebner - Advanced Condition Assessment Strategy for Critical Mains: City of Calgary Case Study
The City of Calgary have long taken a proactive approach to the management of their feedermain network. This includes an advanced condition assessment strategy that combines an inspection program and risk analyses to develop a better understanding of the safety and reliability of the network. The program began in 2004, after a 1200 mm feedermain catastrophically failed and released 20 ML of water, flooding a roadway and disrupting service to over 100,000 customers. An investigation determined the failure occurred on a pipe section with coating that was eaten away in sulfate rich soils, allowing water to seep in and corrode the steel structure of the pipe. Over the years successful inspections have allowed the City to proactively repair damaged pipes. Recently, an advanced condition assessment was completed on a 15 km feedermain jointly owned with the neighboring City of Airdrie.
This presentation will provide an overview of Calgary’s long-term strategy to pipeline management. Success stories, including damaged pipes that were identified and repaired prior to a failure, will be highlighted, along with program and inspection challenges.
|9:45 - 10:30 AM||Morning Break|
|10:30 - 11:00 AM|
Pradeep Dhoraty - Modelling Cumulative Internal Corrosion in SAGD Wells
Corrosion that can occur in various parts of a SAGD well pair due to presence of H2S and CO2 is studied using Wood’s dynamic SAGD simulator combined with its corrosion model. The SAGD simulator is a transient model of the SAGD process including steam injection, the steam chamber, the reservoir, the oil production and steam tubing, annulus and ESP. The dynamic behaviour of the system and the surge volumes in the annulus is studied over a 6 month period using field data. The instantaneous corrosion rates are calculated at multiple locations for various dynamic thermo-hydraulic conditions predicted by the simulator. A strong correlation is observed between the SAGD production rates and the instantaneous corrosion rates. The instantaneous rates for both normal and pitting corrosion can be very high (i.e., 10 mm/yr.). The simulations showed that poor ESP control may lead to 100% increase in the corrosion rate in the annulus. The instantaneous corrosion rates are integrated over the period of operation to calculate expected cumulative values. The cumulative rate of corrosion in the annulus is about 1 mm/yr. due to the changes of the liquid levels and the H2S causing pitting. The corrosion values observed in the annulus can be 10X compared to other parts of the system.
Kevin Sunderman - Corrosion and Stray Current Control Planning for DC Transit Systems
Corrosion can have a major effect on material sustainability of a DC Transit system’s infrastructure and on adjacent metallic utilities. Corrosion control must be implemented in the design, installation, inspection and maintenance plans of any DC Transit system. Being proactive at the front end of any project can pay huge dividends over the planned life of infrastructure and utilities materials.
This paper outlines the causes of corrosion, including soils and stray current from a DC Transit system, and the control concepts that one needs to build into a Corrosion and Stray Current Control Plan. These control concepts ensure that project infrastructure and utilities designs, construction methods and long term operational plans will control/mitigate the corrosion risk to the materials being utilized. This plan should include environment corrosion control (soils and atmospheric), preventative design strategies to minimize stray current at the source, monitoring and testing strategy and where necessary the mitigation of stray currents. A successful corrosion control plan will also include site investigations and inspections, as well as testing and monitoring, before, during and after construction, to ensure that the corrosion and stray current mitigation plan objectives are met over time. A key focus will be on Inspection and Testing during construction. Typical examples of improperly installed systems that can be avoided with a detailed Inspection and Testing Plan (ITP), executed by knowledgeable inspectors, will be provided.
|11:00 - 11:30 AM|
Patrick Teevens - Internal Corrosion Predictive Modelling (IPCM) of downhole OCTGs
This paper reviews the successful prediction of historic and projected downhole internal corrosion of OCTG’s based on operational parameters over the life-to-future-date of an operating well via internal corrosion predictive modeling (ICPM). The specific corrosion engineering assessment of an offshore Newfoundland crude oil well was applied using the appropriate engineering assessment tools involved in ICPM. The historical operating eras or time-periods of the cumulative corrosion predictions were compared to a downhole caliper tool run which confirmed the damage predicted with all results were consistent with related pipeline ICDA acceptance levels of ±10%. The results confirmed the actual average tubular wall losses were very close to the average results predicted. This approach gives the oil or gas petroleum operator viable and non-intrusive options in assessing the impact of downhole corrosion without interrupting production operations.
Christian Bonilla - Risk Assessment and Mitigation Strategy for Ammonium Copper Arsenate (ACA) Pole thru Bolts Corrosion
Powertech investigated the extent of corrosion on through bolts installed in ACA (Ammonium Copper Arsenate) treated wood poles. The study included: 1) sampling and inspection of bolts removed from the BC Hydro Distribution system, 2) mechanical test to determine the tensile and shear capacity of selected bolts with various degrees of corrosion levels, 3) mock up test to evaluate the risk of bolt failure under various operating load conditions, 4) life data analysis (reliability analysis) to determine whether the ACA pole through bolts can survive the life span of the ACA wood pole (50 years), and 5) development of a risk mitigation strategy.
The results of the study showed that: 1) bolts from coastal regions were found to have much higher percentage of severe corrosion compared to the bolts from non-coastal regions, 2) the highest reduction of cross sectional area occurs on the 5/8” bolts, 3) none of the 3/4” bolts were found to have reached their end of life, while a significant number of 5/8” bolts from coastal regions reached end of life, 4) the percentages of bolts that reached end of life in coastal regions were up to 7.3%, while none of the bolts from non-coastal regions were found to have reached end of life, 5) Through bolts on ACA treated Douglas fir poles in coastal regions have the highest rates in terms of cross-sectional reduction and end of life being reached compared to bolts installed in other pole species, 6) the mortality curve obtained from the reliability analysis exhibited that ACA pole through bolts’ mean time to failure (MTTF, end of life) equals 63 years, which is 13 years longer than the average life span of a BC Hydro distribution wood pole (50 years).
In the end a risk strategy was developed to mitigate the risk of bolt failure taking into account location, structure types, poles species, application of load, and work activity.
|11:30 - 1:00 PM||Lunch Break (Note: lunch is not provided on this day)|
|1:30 - 4:00 PM||Regulatory Panel - Management Systems |
|Leadership Forum |