IECM Program is a Iterative Method for Control and Continual Improvement
The IECM program, or the Integrated External Corrosion Management program, is an iterative method for the control and continual improvement of processes related to external corrosion management in pipelines. The program consists of five phases:
Predict Phase: This phase begins with a robust risk assessment aimed at quantifying relative corrosion risk across the pipeline network. The prediction phase begins by reviewing the mechanistic model to determine its suitability for an integrated approach.
Measure Phase: In this phase, various IECM response protocols are defined and deployed in proportion to the determined level of risk. These protocols include activities such as external corrosion direct assessment, installation of new cathodic protection systems, upgrades to existing cathodic protection, and increased surveillance.
Study/Correct Phase: This phase determines if reliability targets are being met because of the responses outlined in the Measure Phase. If the segment meets these targets, continuous improvement activities may begin. If targets are not met, additional risk reduction activities must be initiated in the short-term.
Continuous Improvement Phase: In this phase, IECM segments that have met reliability targets are candidates for optimization of external corrosion protection system operation according to the IECM reliability category as defined above.
Validate Phase: This phase is conducted to determine if the implemented optimization measures have improved the pipeline's reliability targets. If the pipeline meets the targets, the process starts again with the Predict Phase. If not, the pipeline goes through the corrective actions and subsequent validation phase until the targets are met.
By following these five phases, the IECM program ensures the safety and efficiency of pipeline operation by providing a systematic approach to external corrosion management.
IECM Process
Learn more about the IECM Program
The IECM Process
Model
The IECM (Integrity Engineering and Corrosion Management) model is founded on an iterative approach that allows for the control and continuous improvement of processes. The IECM model's first stage is the risk assessment phase, which is designed to quantify the relative corrosion risk across a pipeline network. The risk assessment, also known as the "Predict" phase, is a crucial step in the IECM cycle. The Predict phase commences with a thorough review of the mechanistic model used to assess the pipeline's integrity. The objective of this review is to determine the suitability of the model for an integrated approach, which forms the foundation of the IECM model. The mechanistic model utilizes numerical simulation software that collects environmental, pipeline integrity, and corrosion control data. It employs the Boundary Element Method (BEM) with Finite Element Modeling (FEM) to calculate pipeline potential, current density distribution, and corrosion growth rates in complex buried pipeline networks. The following external corrosion parameters are simulated:
• On Pipe-to-Soil Potential
• IR-Free Potential
• Polarization
• DC Current Density
• AC Voltage
• AC Current Density
• Soil resistivity
• Coating Resistance
• Corrosion Growth Rate (CGR)
The model simulations are then compared to corresponding real-world data to assess the degree of agreement, known as the model alignment confirmation. The comparison results are used to determine if the model aligns with field observations statistically. When the model and field measurements are aligned, the pipeline segment qualifies for IECM, and the process continues. Otherwise, data gap analysis and corrective action recommendations are generated for further assessment. The Probability of Exceedance (PoE) describes the likelihood that mechanical demands placed on the pipeline through normal operation will exceed the structure's capacity over a given period. The PoE is provided to the IECM program team as a function of predicted CGRs by the Pipeline Integrity team. The Consequence of Release (CoR) is determined by considering factors involved in repair and remediation in the event of a release, such as safety, environmental, and economic impacts. The IECM segments are divided into three categories, each with defined external corrosion control key performance indicators (KPIs). These KPIs provide the ECP with guidance for operating and maintaining the pipeline segment. Depending on the results of the validation (check) phase, these KPIs are used for continuous improvement measures. The IECM model's Predict phase is a critical step in ensuring the safe operation and management of a pipeline network.
PREDICT
The Risk Assessment (Predict) phase is an essential part of the IECM continuous improvement cycle, which aims to quantify relative risk across a pipeline network. The phase starts by reviewing the mechanistic model to ensure it's suitable for an integrated approach.
The IECM methodology utilizes numerical simulation software that collects environmental, pipeline integrity, and corrosion control data. It employs Boundary Element Method (BEM) with Finite Element Modeling (FEM) to calculate potential, current density distribution, and corrosion growth rates in complex buried pipeline networks. External corrosion parameters such as Pipe-to-Soil Potential, IR-Free Potential, Polarization, DC Current Density, AC Voltage, AC Current Density, Soil Resistivity, Coating Resistance, and Corrosion Growth Rate (CGR) are simulated.
The model simulations are compared with corresponding real-world data to determine the level of agreement (alignment). These data are used to statistically determine whether the model is aligned or not. Data gap analysis and corrective action recommendations are generated for further assessment. If the model and field measurements are aligned, then the pipeline segment qualifies for IECM.
The Probability of Exceedance (PoE) is used to describe the likelihood that mechanical demands placed on the pipeline through normal operation will exceed the structure’s capacity over a given period. Probabilistic analysis is based on different limit states, and Enbridge's Pipeline Integrity team provides PoE to the IECM program team as a function of predicted CGRs.
Consequence of Release (CoR) is determined by considering factors involved in repair and remediation in the event of a release, such as Safety Impacts, Environmental Impacts, and Economic Impacts.
Integrity risk is determined as a function of the modeled corrosion growth rate (CGR) for aligned pipelines. The pipeline is divided into IECM segments according to variations in risk category. External corrosion control key performance indicators (KPI) are defined for each IECM segment, providing ECP with guidance for operating and maintaining the pipeline segment. Depending on the results of the validation (check) phase, these KPIs are used for continuous improvement measures.
The pipeline is divided into IECM segments according to variations in risk category:
- Risk Category I - High level of integrity risk
- Risk Category II - Moderate level of integrity risk
- Risk Category III - Low level of integrity risk
External corrosion control key performance indicators (KPI) are defined for each IECM segment, including IR-free pipe-to-soil potential, cathodic polarization, AC voltage, and corrosion growth rate. These KPIs are used for continuous improvement measures, depending on the results of the validation (check) phase.
Measure
The IECM Response (Measure) Phase is a critical component of the IECM continuous improvement cycle. This phase aims to maximize the safety and efficiency of pipeline operations by responding to the risks identified in the risk assessment (Predict) phase through various "what-if" simulations. The IECM response protocols are defined to deploy resources in proportion to the level of determined risk.
Specific IECM responses are prescribed based on the risk assessment results, which include external corrosion direct assessment (ECDA), installation of new cathodic protection system(s), upgrades to existing cathodic protection, cathodic protection system output adjustments, interference mitigation (AC or DC), close-interval survey (CIS), in-line inspection (ILI), increased surveillance, such as remote monitoring, electrical isolation, coating repairs, and rehabilitation.
The IECM program further utilizes mechanistic modeling to determine the effectiveness of these response measures before implementation, reducing trial-and-error cycles of the IECM. This modeling ensures that the response measures selected are effective and efficient in addressing the identified risks, resulting in a more reliable and safe pipeline network.
Validation
In the IECM Model, the Validation Phase (Study / Correct) is a crucial step that ensures the safety and reliability of the pipeline operation. The primary objective of this phase is to determine whether the responses prescribed in the IECM Response Phase have effectively reduced the pipeline's risk level to an acceptable level.
In this phase, the pipeline's reliability metrics are analyzed against the IECM predictions to determine if the pipeline is being operated safely (Study). If the reliability targets are met, the continuous improvement activities may commence to enhance the pipeline's safety and efficiency further. On the other hand, if the targets are not met, immediate corrective measures must be initiated (Correct). These additional risk reduction activities may include implementing some of the response measures outlined in the IECM response phase, such as ECDA, cathodic protection, CIS, ILI, coating repairs, etc.
Once the corrective measures are implemented, the validation phase is repeated until the reliability targets are met. This iterative approach helps reduce trial-and-error cycles of the IECM and ensures that the pipeline's safety and reliability are continuously monitored and improved.
In summary, the Validation Phase is a critical step in the IECM Model, which helps determine whether the pipeline is being operated safely and efficiently. By conducting regular validation checks and taking corrective actions when necessary, the IECM Model helps to reduce the risk of pipeline failures and ensures the safety and reliability of the pipeline network.
Continuous Improvement
The continuous improvement phase of the IECM model involves identifying pipeline segments that have met the reliability targets set in the validation phase. These segments are then candidates for optimizing the external corrosion protection system operation based on the IECM reliability category. The goal is to improve the efficiency and safety of the pipeline operation further.
Before implementing any optimization measures, the effectiveness of each option is validated in the numerical model to determine the potential impact on pipeline integrity. This process reduces trial-and-error cycles and ensures that only the most effective measures are taken.
Examples of optimization measures that may be recommended include rebalancing the cathodic protection system output, adjusting the quantity and configuration of test points, and modifying monitoring frequency. The IECM may also recommend changes to the configuration of AC/DC interference mitigation or monitoring.
By continuously assessing and optimizing the external corrosion protection system, the IECM model ensures that the pipeline operation remains reliable and efficient over the long term.
