HRSG Pressure Part/Tube Panel Replacement

This seminar is primarily intended for HRSG Owners, Asset Managers, and O&M Management but will be useful for almost anyone working with Combined Cycle or Cogeneration Plants with Heat Recovery Steam Generators. HRSGs have generally high reliability with regard to pressure parts including tubes, piping and headers but inspection, testing and repairs are more difficult and time consuming than in other boilers. In many cases by the time leaks are evident, damage to the tubes, tube panels (HARPS) and tube modules can be widespread.    Repairs can require complete replacement of HARPS and/or entire tube modules.  These require advance planning and procurement to be done successfully in an operational HRSG. Extensive repairs and replacements can also be required due to defects in fabrication, construction and commissioning or from accidents such as gas turbine fires and explosions. Tetra Engineering has supported plant owners, operators and others in these major events for many years.   We have supplied forensics, engineering oversight, due diligence, factory and erection oversight and support for owners in disputes worldwide   This seminar will be presented by experienced instructors in all these areas.


Seminar Syllabus

Introduction and Overview 

  • HRSG Basics (major components, design options, variants)
  • Why Modern HRSG’s Present difficulties for major repairs and replacements
  • Pressure Part Failures in HRSGs and Impact on key reliability and availability metrics

Causes of HRSG Pressure Part Failures 

  • Key Types of Failures
  • Failures from Fabrication Quality issues
  • Failures during Commissioning
  • Failures from operational issues (corrosion, fatigue, overheating and others)
  • Failures from Other Causes.

HRSG Life Management for High Reliability and Availability 

  • Monitoring, Inspection and Useful Remaining Life Assessment
  • Consideration of Operational Changes (Cycling, Low Load, Flexible Operation, Alternate Fuels)

HRSG Pressure Part Repair and Replacement Options

  • Individual Tube Replacement/Plugging/Repair
  • Tube Panel Replacement (Single HARP or Selected HARPS)
  • Tube Module Replacement

Engineering, Procurement, Replacement Actions for HRSG Pressure Parts

  • Specification Development for replacement or upgrade and replace options
  • Re-Engineering Considerations
  • Procurement and Installation Options (Single Source OEM, EPC or Split Contracts)
  • Typical Schedule and Price Issues (local or off-shore sourcing, fabrication options, construction management)
  • Project Supervision and Oversight

HRSG Pressure Part Replacement Case Studies 

  • Extensive Design/Fabrication Quality Issues in New Plant
  • Partial Replacement of Evaporator Tubes
  • Full Replacement of Evaporator Modules
  • Replacement of Tubes Damaged in Turbine Accidents 
  • Partial HARP replacements
  • Issues in Replacement Access

This seminar will be presented by experienced instructors in all these areas.


Please contact Christine Vallon for registration or information purposes at This email address is being protected from spambots. You need JavaScript enabled to view it. or by telephone on +33 4 92 96 92 54. 

Summer Power Seminars

On the French Riviera, June 10-14, 2019

Partners: TG Advisers, USA; Prof. B Leckner, Chalmers University of Technology

A unique opportunity to update your knowledge on your power plant’s Capital Equipment. Hear from industry-leading experts on Gas Turbines, HRSGs, Fluidised Bed Boilers and Steam Turbines. Sharpen your skills with the latest information on inspecting, analysing and maintaining your critical power generation assets.

Tetra Engineering has partnered with turbine experts TG Advisers Inc., and Fluidised Bed Boiler expert Prof. B. Leckner (Chalmers University of Technology, Sweden) to deliver a comprehensive course set, targeted at O&M engineers with critical technical responsibilities. The programme will run as follows:

Nice Wikimedia

May 2019: Effective HRSG Operations

May 15 & 16, 2019 at The Chateaux Deer Valley in Park City, Utah USA


Course Overview:

This seminar is primarily intended for O&M staff at all levels of experience working in combined cycle power plants, but should also be of interest to engineers and managers involved in new project development. The course gives attendees a comprehensive yet in-depth survey of a broad range of topics relating to the design, operation and maintenance of the HRSG and associated steam cycle systems. This year we’ve added additional material on emissions controls by SCR and CO catalysts as well as additional insights on chemical and fireside cleaning, low load operation and desuperheater design. Also included is a discussion on HRSG Fabrication and Procurement.

Drawing on our field experience working at power plants throughout the world, the objective is to provide attendees with clear instruction on the operator actions and design issues that impact HRSG reliability, efficiency and operating life.

Tetra Engineering has offered this seminar for many years and it is updated annually. Recent seminar sites have included USA, Turkey, UAE and Malaysia. The instructor /seminar leader is David Moelling, P.E., Tetra Engineering’s Chief Engineer. He has presented these seminars for over 15 years. Ms. Early Femiana will discuss the details of HRSG specification, manufacture, shipping and assembly from her 10 years with GE/Alstom for all types of HRSGs.

Combined Cycle Power Plant Fundamentals


Gas Turbine Combined Cycle (GTCC) technology is a leading solution in improving efficiency and reducing emissions. The course provides an introduction to the basic thermodynamic concepts underlying the design and operation of GTCC plants, followed by a description of the major components and their operation.  Participants will complete the course with an understanding of what drives the performance of the integrated plant.  

The one day course is suitable for anyone with a general technical background that is or will be involved in the construction, operation or management of GTCC power plants. 

Course Syllabus

Thermodynamic Fundamentals

Introduction and Review of Thermal Power Cycles

  • Ranking and Carnot Cycles
  • Conventional Boilers
  • Combined Cycle Gas Turbine (CCGT) Plant Basics
  • History and Evolution of CCGT
  • Future Trends in Power

The Gas Turbine (GT)

  • Design Fundamentals
  • Types and Applications

The Heat Recovery Steam Generator (ST)

  • Design Fundamentals
  • Design Variants
  • Key Components

The Steam Turbine (ST)

  • Design Types
  • Key Components
  • Operation

Electrical Plant

  • Basics
  • AC Generators
  • Switchgear and Transformers


  • Air, Water and Fuel Supply
  • Emissions Control
  • Cooling Systems
  • Piping and Pumps

Operational Aspects

  • Startup, Cycling & Load Changes
  • Preservation
  • Alternate Fuels
  • Plant Protection and Control
  • Lifetime and Mainteance Issues
  • Performance Tracking

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

Root Cause Analysis for Boiler & HRSG Failures


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, HRSG and 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

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)
  • 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.

This course is offered in a 3 day format and a condensed 1 day format.

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 1988, 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.


Our Locations

Offices in: Connecticut, USA; Nice, France; Dubai, UAE.