Root Cause Analysis for Boiler & Steam Cycle Failures

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This training course is primarily intended for experienced O&M staff working in thermal power and process plants as well engineering and management staff at the corporate level. The objective is to give attendees all the essentials for effective determination of the root cause of failures that can occur in the boiler or associated steam balance-of-plant. The principal failure modes are reviewed, with focus on those occurring in the boiler, critical piping and other key components such as pressure vessels and condensers. Major emphasis is placed on analyzing how upstream events in the steam cycle process can lead to failures in downstream components. Several actual failure case histories treated by Tetra Engineering staff at plants around the world are presented, providing attendees with practical application of the presented concepts.

Course Syllabus

Review of Steam Cycle Damage Mechanisms

Gain an overview of the most common damage mechanisms, either on the waterside or fire/gas/air-side, that can affect components in the steam cycle

  • General Surface Corrosion
  • Pitting Corrosion
  • Flow Accelerated Corrosion, Cavitation and Fluid Erosion
  • Underdeposit Attack
  • Fatigue and Corrosion Fatigue
  • Creep, Creep Fatigue and other Heat Damage
  • Fire or Gas Side Erosion or Attack
  • Gas and Waterside Fouling
  • Hydrogen Embrittlement
  • Stress-Corrosion Cracking

Steam Cycle Components and Failure Modes

A summary of failure modes and mechanisms most frequently observed in various steam cycle components

  • Boiler Tubes and Internal Pressure Parts
  • Boiler Gas Path and Exterior
  • Power Piping (Condensate, Feedwater and Steam)
  • Valves and Pumps a (Summary with Focus on Major Items)
  • Condensers and Other Heat Exchangers
  • Pressure Vessels

Collecting Evidence and Identifying the Failure Mechanism

The key first step is to define the problem, collect the evidence and then identify the component failure mechanism. It’s important to remember that this is usually not the same as the failure root cause.

  • Defining the Investigation Scope
  • Collecting the Field Evidence: Visual, NDE and Destructive Samples
  • Process Data Collection
  • Overview of Laboratory Analytical Techniques
  • Getting the Most Out of Metallurgy
  • Effective Reporting

Root Cause Analysis Methods

There are several methods or approaches to determining the root cause, these are presented in summary fashion here as background. Despite their differences, all follow a similar overall strategy and aim to achieve the same goal. Whatever the method chosen, it is important to remember that the ultimate objective is to find a solution that prevents further failures.

  • Five Whys
  • Failure Modes and Effects Analysis (FMEA)
  • Pareto Analysis
  • Fault Tree Analysis
  • Current Reality Tree
  • Fishbone Diagram
  • Kepner-Tregoe Method
  • RPR Problem Diagnosis

Sample Case Histories and Discussion

Examples from recent projects performed by Tetra staff are presented, covering failure analyses on a variety of steam cycle pressure part components

  • Steam Turbine Corrosion
  • HRSG Casing Vibration
  • Superheater Tube CrackingFailure 1
  • Superheater Tube Burst Failure
  • HRSG LP Evaporator Tube Burst Failure
  • Boiler Tube Fouling
  • Others…….


For  more information about this course please contact Christine Vallon, or call our European office at +33 4 92 96 92 54. Tetra offers courses on client site or as per our public course schedule

About Us

Established in 1989, Tetra Engineering has more than 25 years experience providing solutions to the power industry. We specialize in solutions for HRSGs, conventional boilers & steam-cycle balance of plant.