CORROSION MANAGEMENT
Understanding
Damage Mechanisms
Resources supporting corrosion
control,inspection planning,
& mitigation strategies.

Inspection Beyond Compliance

Corrosion is one of the most common causes of fixed equipment degradation, loss of containment, and unplanned maintenance. Effective corrosion management requires more than periodic thickness readings—it requires understanding how degradation develops, where it occurs, why it accelerates, and how operational changes influence equipment integrity.

At Advanced Inspection Solutions, corrosion management begins with understanding damage mechanisms, process conditions, operating history, and asset-specific risk. AIS integrates API 571 damage mechanism principles with API 580 risk-based methodologies to help owner-operators focus inspection resources where degradation is most likely to occur.

Our objective is simple:
Identify degradation before it becomes failure.

The AIS Corrosion Management Approach

AIS develops inspection strategies that combine:

  • API 571 Damage Mechanism Reviews
  • API 580 Risk-Based Inspection Principles
  • Thickness Monitoring Locations (TMLs)
  • Corrosion Rate Analysis
  • Integrity Operating Windows (IOWs)
  • Process Chemistry Reviews
  • Asset-Specific Inspection Test Plans (ITPs)
  • Fixed Equipment Integrity Programs

The objective is not simply measuring metal loss.
The objective is understanding what drives degradation and managing risk before integrity is compromised.

API 571: Understanding Damage Mechanisms

Effective corrosion management begins with identifying credible damage mechanisms.
AIS utilizes API 571 principles to evaluate degradation risks affecting:

  • Pressure Vessels
  • Process Piping
  • Storage Tanks
  • Fixed Equipment Systems

Common damage mechanisms may include:

  • General Corrosion
  • Localized Corrosion
  • Pitting Corrosion
  • Erosion-Corrosion
  • Corrosion Under Insulation (CUI)
  • Microbiologically Influenced Corrosion (MIC)
  • Sulfidation
  • CO₂ Corrosion
  • Wet H₂S Damage
  • Naphthenic Acid Corrosion
  • Chloride Stress Corrosion Cracking
  • Atmospheric Corrosion

Understanding active damage mechanisms allows inspections to focus on the most likely failure locations.

Corrosion Circuit Development

AIS places significant emphasis on corrosion circuit development.
Corrosion circuits group equipment and piping systems with similar degradation characteristics, allowing inspections to focus on areas exposed to similar corrosion risks. Circuit development may consider:

  • Process chemistry
  • Flow characteristic
  • Operating temperatures
  • Water content
  • Corrosive contaminants
  • Injection locations
  • Metallurgy
  • Historical inspection data

Corrosion circuits provide a more effective framework than treating an entire process unit as a single inspection area.

Condition Monitoring Locations
(CMLs)

Effective corrosion monitoring depends upon quality data collection.
AIS assists clients with developing Condition Monitoring Locations based on:

Well-positioned CMLs improve corrosion rate accuracy, remaining life calculations, and future inspection planning.

Corrosion Rate Analysis

Corrosion rates help determine the condition and projected life of equipment.
AIS utilizes corrosion data to evaluate:

Long-Term Trends

  • Historical degradation
  • Equipment aging
  • Integrity planning

Short-Term Trends

  • Process changes
  • Operating upsets
  • Accelerated degradation
  • Emerging risks

Corrosion rate analysis supports:

  • Remaining life calculations
  • Inspection interval decisions
  • RBI assessments
  • Mechanical integrity planning

Process Chemistry
& Flow Characteristics

Corrosion rarely occurs without a cause.
AIS evaluates process variables that may influence degradation, including:

  • Water content
  • pH
  • Chlorides
  • H₂S
  • CO₂
  • Oxygen ingress
  • Flow velocity
  • Turbulence
  • Chemical treatment effectiveness

Understanding process chemistry often explains why one component experiences significant degradation while similar equipment remains unaffected.

Integrity Operating Windows
(IOWs)

Corrosion rates are directly affected by operating conditions.

AIS encourages owner-operators to establish Integrity Operating Windows that monitor variables capable of influencing degradation.

Examples include:

  • Temperature
  • Pressure
  • Velocity
  • Water content
  • Corrosive contaminants
  • Chemical concentrations
  • Treatment rates

Monitoring these variables helps identify changing conditions before increased corrosion rates impact equipment integrity.

Corrosion
& Risk-Based Inspection

Corrosion management and Risk-Based Inspection work together.
AIS utilizes corrosion data to support:

Probability of Failure

Evaluating:

  • Active damage mechanisms
  • Corrosion rates
  • Remaining life
  • Inspection effectiveness
  • Equipment condition

Condition Monitoring Locations (CMLs)

Evaluating:

  • Personnel exposure
  • Environmental impact
  • Product release potential
  • Production loss
  • Business risk

This approach helps prioritize inspection resources where corrosion presents the greatest mechanical integrity concern.

Asset-Specific Inspection
Test Plans
(ITPs)

AIS develops corrosion-focused inspection strategies based on:

Equipment Design

  • Pressure vessels
  • Process piping
  • Storage tanks
  • Fixed equipment systems

Operating Conditions

  • Temperature
  • Pressure
  • Flow regime
  • Process variability

Process Chemistry

  • Corrosive species
  • Water content
  • Chemical treatment programs

Historical Findings

  • Corrosion rates
  • Thickness trends
  • Previous repairs
  • RBI results

Every asset should be inspected based on its own degradation risks rather than a one-size-fits-all approach.

AIS
Philosophy

Many corrosion programs focus on metal loss.

AIS focuses on understanding why the metal is being lost.

By combining API 571 damage mechanism identification, API 580 risk methodologies, and asset-specific inspection planning.

AIS develops corrosion management strategies that support:

  • Safer operations
  • Improved reliability
  • Reduced loss of containment events
  • Better inspection effectiveness
  • Stronger mechanical integrity programs

Stewardship Quote

"Corrosion is not the problem—unmanaged corrosion is. Effective stewardship begins by understanding degradation, managing risk, and acting before integrity is lost."

— Kevin B. Hudgens
Founder & Principal Inspector
Advanced Inspection Solutions
ASSET INTEGRITY & RELIABILITY LIBRARY

Corrosion Management Resources

Technical resources supporting corrosion monitoring, damage mechanism awareness, remaining life evaluation, and long-term asset integrity.