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Damage Mechanisms

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Damage Mechanisms (also referred to as degradation mechanisms) is a general term referring to any cause of problems or failures within process equipment. These can range from corrosion, to cracking, to heat damage, and everything in between.

When assessing damage mechanisms, one must take into account the current state of the equipment, as well as any potential damage the mechanism may cause later. Equipment’s susceptibility to a particular damage mechanism is affected by a number of variables, including materials of construction, process fluids, operating conditions, external environment, etc. A good understanding of the variety of damage mechanisms that exist is a must for any mechanical integrity program.

A thorough damage mechanisms review is essential for creating an effective inspection strategy. Once damage mechanisms and morphology are understood, inspection strategists can use this information to select inspection methods with the highest probability of detecting, characterizing, and measuring potential damage. Furthermore, inspection intervals can be established using industry codes and standards such as API 510, 570, 653, API RP 579 for fitness-for-service, and API 580 and 581 for risk-based inspection.

Some of the most common damage mechanisms in the refining and chemical processing industries are:

  • Corrosion Under Insulation (CUI), which occurs when moisture builds up on the surface of insulated equipment.

  • Sulfidation Corrosion, a type of corrosion that occurs at temperatures above 500 °F (260 °C) due to sulfur compounds in crude.

  • High Temperature Hydrogen Attack (HTHA), a mechanism that can affect equipment that is exposed to hydrogen at elevated temperatures (at least 400 °F or 204 °C)

  • Wet H2S Damage, which can occur when atomic hydrogen from wet H2S corrosion reactions enters and weakens the steel.

  • CO2 Corrosion, which is a form of degradation that occurs when dissolved CO2 in condensate forms carbonic acid, which corrodes steels.

  • Hydrogen Embrittlement, which happens when atomic hydrogen infuses into certain higher strength steels and causes them to become brittle

  • Brittle Fracture, which is the sudden, very rapid fracture under stress where the material exhibits little or no evidence of ductility or plastic degradation before the fracture occurs.

  • Phosphoric Acid Corrosion is an acidic environment "disease" largely associated with polymerization units using phosphoric acid as a catalyst. Dry phosphoric acid catalyst is not corrosive to carbon steel, but wet phosphoric acid can corrode carbon at thousands of mils per year. This type of corrosion can often be found in dead zones and crevices where wet acid can drop out. In places where water is present, upgrading to 304L, 316L, or Alloy 20 may be necessary to prevent this type of corrosion, depending on the temperature.[1]

Damage mechanisms are detailed and covered at length in API RP 571, Damage Mechanisms Affecting Fixed Equipment in the Refining Industry. This document provides an in-depth look at over 60 different damage mechanisms that can occur to process equipment in refineries. It includes a general description of the damage mechanism, susceptible materials of construction, critical factors, inspection method selection guidelines, and control factors.

References

  1. 99 Diseases of Pressure Equipment: Phosphoric Acid

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Articles about Damage Mechanisms
July/August 2021 Inspectioneering Journal

This article discusses how composite materials can be used to mitigate light CUI damage and/or repair and restore structural strength to the affected piping system.

Authors: Casey Whalen
July/August 2021 Inspectioneering Journal

Recent advances in UT technology now allow for inspection and continuous monitoring of sulfidic corrosion to be undertaken while the components are on-stream, at temperature, with high-resolution thickness data.

Authors: Tim Stevenson
July/August 2021 Inspectioneering Journal

The scope of the subject case study reviews an inspection and corrosion control assessment conducted on subsea flowlines and includes evaluating the flowlines’ associated inspection programs and identifying all available NDT technology solutions.

July/August 2021 Inspectioneering Journal

Practical steps to mitigate corrosion under insulation (CUI) damage on fixed pressure equipment and commentary on common mitigation techniques and good engineering practices for external insulation or fireproofing system design and application.

May/June 2021 Inspectioneering Journal

Hydrogen-induced damage mechanisms have been studied endlessly, leading to changes in equipment design and development of new inspection practices. However, the highly localized nature and difficulty of detection of HTHA add additional complexities.

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May/June 2021 Inspectioneering Journal

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May/June 2021 Inspectioneering Journal

In this article, FFS assessment methods are summarized and practical guidance is offered for qualifying CUI damage on carbon and low-alloy steels.

March/April 2021 Inspectioneering Journal

This article provides insights into the AIV damage mechanism, reviews approaches to calculate the probability of AIV failure in piping, provides design practices to prevent AIV failure, and introduces a RBI approach to evaluate risk of AIV failures.

March/April 2021 Inspectioneering Journal

Corrosion under insulation is a form of external corrosion that is caused by trapped water on insulated surfaces. It is an industry problem affecting equipment in the oil and gas, petrochemical, specialty chemical, fertilizer, and related industries.

January/February 2021 Inspectioneering Journal

The first two parts of this series covered the basics of fracture mechanics and how the FAD is interpreted. This article touches on a few practical points regarding the application of fracture mechanics in a plant environment.

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January/February 2021 Inspectioneering Journal

Thermal fatigue, a specific form of fatigue driven by varying metal temperature gradients and ensuing differential thermal expansion, is generally most effectively mitigated by reducing the severity of metal temperature gradients.

January/February 2021 Inspectioneering Journal

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November/December 2020 Inspectioneering Journal

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November/December 2020 Inspectioneering Journal

Every fitness-for-service (FFS) assessment must have a well-defined acceptance criterion. For many damage mechanisms, it’s the “remaining strength factor” (RSF). But for crack-like flaw assessment, it’s the Failure Assessment Diagram, or FAD.

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September/October 2020 Inspectioneering Journal

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September/October 2020 Inspectioneering Journal

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September/October 2020 Inspectioneering Journal

This article reflects the first in a series on damage mechanisms that will appear in this recurring Inspectioneering column entitled “Damage Control.” The inaugural topic discussed in this column is thermal fatigue.

July/August 2020 Inspectioneering Journal

Ideally, all valves should work when needed; but the truth is that valves fail. This article discusses the common failure mechanisms that affect valves as well as what inspectors should look for during an inspection.

July/August 2020 Inspectioneering Journal

Assessment procedures in API 579 are organized by damage mechanism. But what happens when different damage mechanisms are in play since the evaluation criteria may not be compatible?

Authors: Greg Garic
March/April 2020 Inspectioneering Journal

Nelson curves, which are the foundation of the industry’s HTHA programs, can be tied to mechanistic models from several sources, allowing the recreation of Nelson curves for different operational histories and time durations.

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January/February 2020 Inspectioneering Journal

The purpose of this article is to describe some of the pitfalls that operating sites have encountered while trying to implement a program of IOWs in accordance with the guidance in API RP 584, plus how to overcome those pitfalls.

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January/February 2020 Inspectioneering Journal

This article addresses two failure events where inadequate attention to thermal fatigue led to premature equipment failure while specifying guidelines to help prevent such failures that can be a part of a plant's inspection and maintenance programs.

January/February 2020 Inspectioneering Journal

There are many sources and occurrences of metal fatigue in the chemical and refining industries. They range from low-cycle thermal stresses in an FCCU, to the relentless pressure cycling of a PSA, to the ultra-high cycles of a rotating pump.

Authors: Greg Garic
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September/October 2019 Inspectioneering Journal

A damage mechanism review, or DMR, is a structured process performed by a qualified team to gain a better understanding of unit operations, corrosion loops, materials of construction, and potential damage types and locations.

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July/August 2019 Inspectioneering Journal

A significant number of pipeline failures due to external or internal corrosion have resulted from MIC, some with catastrophic consequences. This article demonstrates a three-step failure analysis process used to investigate the failure mechanism.

July/August 2019 Inspectioneering Journal

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May/June 2019 Inspectioneering Journal

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Authors: Nick Schmoyer
May/June 2019 Inspectioneering Journal

A well-implemented and managed reliability program incorporating RBI, DMR, and IOWs can identify potential damage mechanisms, optimize maintenance and inspection activities, reduce risks, and improve the governance in managing Ethane Crackers.

January/February 2019 Inspectioneering Journal

This article provides a summary of the 2019 API Inspection & MI Summit keynote address, which offers a past, present, and future outlook on fixed equipment mechanical integrity from an industry professional with 50+ years of experience.

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September/October 2018 Inspectioneering Journal

This article discusses the advances in NDE that have given owners increased confidence on how to assess equipment integrity in HTHA service providing risk prioritization of equipment as well as providing the ability to make more reliable...

September/October 2018 Inspectioneering Journal

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May/June 2018 Inspectioneering Journal

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May/June 2018 Inspectioneering Journal

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May/June 2018 Inspectioneering Journal

HTHA of hydrogen-containing equipment can be prevented with appropriate material selection and fabrication, appropriate welding procedures, regular inspection of equipment using proven, effective technologies and equipment operated by qualified...

Authors: Samer E. Ibrahim
March/April 2018 Inspectioneering Journal

Hot spots – localized areas of overheating in pressure equipment – can lead to deformation or even loss of process containment. It is important to understand the effects of elevated temperature caused by hot spots on the mechanical integrity of...

January/February 2018 Inspectioneering Journal

Sea water corrosion and erosion issues can affect almost all commonly used metallurgy in a refinery or petrochemical plant. This brief article explains the dangers behind sea water used in plant cooling systems and discusses several metallurgical...

Authors: Ashfaq Anwer
January/February 2018 Inspectioneering Journal

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November/December 2017 Inspectioneering Journal

Thanks to the development of documents such as API RP 571 and API RP 586, as well as the emergence of qualification demonstration testing, we can align NDT techniques and inspection strategies better than ever. This article examines this progression...

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September/October 2017 Inspectioneering Journal

Fired heaters are among the most critical equipment in refineries and chemical plants. This article provides an overview of what a fired heater tube mechanical integrity program should include.

July/August 2017 Inspectioneering Journal

Failure analysis of piping that has experienced corrosion damage provides operators with valuable information needed to prevent future failures. Effective processes and procedures are essential when investigating the cause of corrosion on pipelines...

May/June 2017 Inspectioneering Journal

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May/June 2017 Inspectioneering Journal

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March/April 2017 Inspectioneering Journal

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March/April 2017 Inspectioneering Journal

This article discusses the use of the RBI methodology supplemented by a well-designed IOW program to assess and manage aging in fixed equipment and piping in hydrogen generation units.

January/February 2017 Inspectioneering Journal

This article summarizes a comprehensive survey conducted by the Research & Development Center (R&DC) of Saudi Aramco to understand top corrosion damage mechanisms experienced by its operating onshore surface facilities.

January/February 2017 Inspectioneering Journal

In this article, the roles and responsibilities of the corrosion and materials SME will be outlined as I see them, fully recognizing that there is probably no one person out there with all the knowledge and skills suggested herein.

Authors: John Reynolds
January/February 2017 Inspectioneering Journal

Historically, if asked when or how likely an austenitic series stainless steel component is to crack, the usual answer was “very” or “maybe” or, later, “I didn’t see that coming.” With API’s new risk assessment methodology, the...

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November/December 2016 Inspectioneering Journal

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September/October 2016 Inspectioneering Journal

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Authors: Kimberley Hayes
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July/August 2016 Inspectioneering Journal

This article summarizes a recent finite element analysis (FEA)-based study that employs creep simulation techniques to investigate the elevated temperature response of piping with peaked longitudinal weld seams.

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November/December 2015 Inspectioneering Journal

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November/December 2015 Inspectioneering Journal

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September/October 2015 Inspectioneering Journal

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November/December 2014 Inspectioneering Journal

This article provides background on HTHA, discusses some current developments in HTHA inspection and mitigation, and describes how one refiner is instituting an HTHA risk management plan for its refineries along with challenges they have encountered.

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September/October 2014 Inspectioneering Journal

Maintaining mechanical integrity for aging power boilers can be challenging. This article provides a case study on how mitigating one damage mechanism led to the discovery of another, and how refinery engineers collaborated with industry experts to...

September/October 2014 Inspectioneering Journal

A small leak from top tubesheet-to-tube welds prompted further inspection of the 1¼Cr- ½Mo Ammonia Converter Boiler Feed Water (BFW) Exchanger during a planned shutdown. Further cracks were identified in the top channel to tubesheet butt weld that...

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I've crunched some numbers and have come up with the three most popular damage mechanisms, based on the activity of our readers, that Inspectioneering publishes information on.

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July/August 2014 Inspectioneering Journal

As any refining or petrochemical plant manager knows, corrosion can occur on insulated piping at any facility. CUI has been a major challenge for the petrochemical and refining industries since the first pipelines were insulated with wrappings.

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March/April 2014 Inspectioneering Journal

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January/February 2014 Inspectioneering Journal

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Last week we mentioned three important tips to consider when addressing high temperature hydrogen attack (HTHA). This week, we'd like to provide the reader with a few helpful resources that deal with the topic of HTHA.

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November/December 2013 Inspectioneering Journal

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September/October 2012 Inspectioneering Journal

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July/August 2012 Inspectioneering Journal

We have recently learned of one organized joint industry project (JIP) that was announced at the Spring 2012 API Refining meeting. As information has become available we have decided to present it to our readership.

March/April 2012 Inspectioneering Journal

What I am primarily concerned with, in this article, is erosion corrosion control. Now, what is erosion corrosion? Well, no matter how you might look at it, erosion corrosion involves the degradation of the material by some mechanical action, in...

November/December 2010 Inspectioneering Journal

High Temperature Hydrogen Attack (HTHA) is a long known and still occurring degradation issue for fixed equipment construction materials in the hydrocarbon process industry where hydroprocess plants (hydrogen plus hydrocarbons) are in service....

Authors: John Reynolds
November/December 2010 Inspectioneering Journal

The following references are from the American Petroleum Institute. They are widely used in the petroleum refining and petrochemical industries for managing equipment in HTHA service and are available in the public domain.

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September/October 2008 Inspectioneering Journal

You're at 32,000 feet in an airplane when you look out the window. You observe the wing of the jet moving up and down with the turbulence, like a child bending a coat hanger over and over again until the wire fractures into two pieces. You wonder...

Authors: Richard Green
March/April 2007 Inspectioneering Journal

A myriad of issues need to be considered before welding to or repairing weld overlayed or clad equipment. (By clad we mean roll-bonded or explosion bonded, i.e. basically 100% metallurgically bonded, and not a loose or seam-welded liner, e.g., not...

Authors: John Reynolds
January/February 2007 Inspectioneering Journal

In previous parts of this series, I have covered many corrosion and degradation issues, some environmental cracking diseases, metallurgical degradation mechanisms, issues associated with welding and some external corrosion problems. In part 14,...

Authors: John Reynolds
May/June 2006 Inspectioneering Journal

As noted in the discussion on delayed cracking, when the steel contains hydrogen as a result of service exposure (or corrosion, or high temperature - high pressure hydrogen processing) then a hydrogen bake out may be needed to avoid cracking...

Authors: John Reynolds
January/February 2006 Inspectioneering Journal

After a pressure equipment or piping failure, it’s not uncommon to find out during the failure analysis part of the investigation that the failure initiated at a welding flaw of some sort.

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September/October 2005 Inspectioneering Journal

Temper embrittlement is another form of metallurgical degradation resulting from exposure of susceptible low alloy steels to higher temperature ranges, usually in service, but can occur to some extent even during heat treatment. And, once again, if...

Authors: John Reynolds
September/October 2005 Inspectioneering Journal

Strain-aging problems are another form of metallurgical degradation and thankfully are not very common and becoming less so; but since strain-aging does still occasionally occur, it still makes the list of one of the “99 diseases of pressure...

Authors: John Reynolds
September/October 2005 Inspectioneering Journal

Another form of metallurgical degradation at higher temperatures is called sigma phase embrittlement. As the name implies, a metallurgical phase change occurs in some stainless steels when they are heated above about 1000F (540C).

Authors: John Reynolds
September/October 2005 Inspectioneering Journal

Titanium (Ti) hydriding is another somewhat unusual metallurgical degradation phenomena that can result in brittle fracture. Unlike many other steel embrittlement phenomena, this one most often occurs in thin wall Ti tubes that have been selected...

Authors: John Reynolds
September/October 2005 Inspectioneering Journal

Metals will slowly deform under stress and higher temperatures by the mechanism known as creep. The amount of creep deformation that will be experienced is highly dependent upon the level of stress, level of temperature and material properties....

Authors: John Reynolds
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September/October 2005 Inspectioneering Journal

Spheroidization is a rather technical term that describes a metallurgical aging phenomena that results in loss of mechanical and creep strength. It occurs when carbon and low alloy steels are exposed to temperatures in the range of 850F - 1400F...

Authors: John Reynolds
July/August 2005 Inspectioneering Journal

This bulletin is part of a series of WRC Bulletins that contain the technical background and other information to evaluate damage mechanisms in various industries to facilitate the use of API 579. These bulletins, shown below, will be updated based...

May/June 2005 Inspectioneering Journal

Carbon dioxide (CO2) corrosion is most typically found in boiler condensate return systems that are not adequately treated with corrosion inhibitors (typically amines). Dissolved CO2 in condensate forms carbonic acid (H2CO3) which corrodes steels...

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May/June 2005 Inspectioneering Journal

Boiler feed water (BFW) corrosion is mostly the result of dissolved oxygen in the feed water, but is also related to the quality of the BFW and the quality of the treatment system.

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May/June 2005 Inspectioneering Journal

Cooling water (CW) corrosion may be the oldest form of corrosion in the petrochemical industry, yet the industry still struggles with it for two primary reasons.

Authors: John Reynolds
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May/June 2005 Inspectioneering Journal

MIC is caused by biological growth, i.e. organic slime (typically bacteria, algae, and fungi) in water under low flow or stagnant conditions. The industry experiences it in cooling water systems, piping, vessels and storage tank bottoms where the...

Authors: John Reynolds
May/June 2005 Inspectioneering Journal

Most all flue gases produced by the combustion of fuels contain contaminants that can condense into acid droplets. The amount of contaminants will determine the concentration of the acid droplets.

Authors: John Reynolds
January/February 2005 Inspectioneering Journal

Polythionic Acid Stress Corrosion Cracking (PASCC) is an affliction of many refineries processing sulfur containing feedstocks, and since that is the norm these days, most refiners reduce their susceptibility to PASCC by selecting resistant alloys...

Authors: John Reynolds
January/February 2005 Inspectioneering Journal

Hydrogen stress cracking occurs when corrosion from acids like wet hydrogen sulfide or hydrofluoric acid (HF) cause atomic hydrogen to penetrate hardened or higher strength steels and cause stress cracking.

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January/February 2005 Inspectioneering Journal

HTHA falls into multiple categories of corrosion mechanisms, including environmentally assisted cracking, hydrogen assisted cracking, and high temperature degradation. Sometimes HTHA is confused with low temperature hydrogen cracking mechanisms...

Authors: John Reynolds
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January/February 2005 Inspectioneering Journal

Corrosion fatigue is closely related to mechanical and vibration fatigue cracking, except that it is initiated and accelerated by a corrosion mechanism, especially one that gives rise to pitting, from which cracks often initiate. But that...

Authors: John Reynolds
November/December 2004 Inspectioneering Journal

Accounts with shop validation on carbon steel samples prior to field trials, on an in-service C 1/2 Mo vessel, were reported at a recent industry conference. The studies were successful in the laboratory and appear to make sense in field trials on a...

September/October 2004 Inspectioneering Journal

Corrosion from HCl is a significant problem in many refining and chemical process units, and often the materials solution to HCl corrosion is rather expensive, since the lower cost, more available alloys are usually not resistant to most...

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September/October 2004 Inspectioneering Journal

Corrosion in the refining industry from HFA is not as widespread a problem as it is with HCl because it is only associated with HF Alkylation Units, which are usually fairly carefully controlled in order to avoid potential for a toxic HFA cloud...

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September/October 2004 Inspectioneering Journal

Problems with naphthenic acid corrosion (NAC) are nearly as old as the refining industry. The first paper on the topic that I knew about was written by one of my early industry supervisors over 40 years ago.

Authors: John Reynolds
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September/October 2004 Inspectioneering Journal

Unlike NAC where we’re still on a learning curve, the knowledge of corrosion by sulfuric acid has not changed much in the last quarter century, and there are many good references for it included in API RP 571.

Authors: John Reynolds
September/October 2004 Inspectioneering Journal

Corrosion from phosphoric acid is another “old knowledge” corrosion issue that effects only a few processes in the chemical and hydrocarbon process industry.

Authors: John Reynolds
July/August 2004 Inspectioneering Journal

Catastrophic oxidation can occur when certain contaminants are present in a high temperature environment, i.e. inside furnace fireboxes, in our industry. Those contaminants are typically vanadium pentoxide with sulfur oxide or sodium sulfate.

July/August 2004 Inspectioneering Journal

Though oxidation and sulfidation are quite prevalent high temperature corrosion mechanisms in many of our process units, we now come to a few that are not very common, but still deserve some attention to make sure they don’t lead to...

Authors: John Reynolds
July/August 2004 Inspectioneering Journal

Metal dusting is simply a severe form or extension of carburization in which the extensive carbides that form as a result of carburization lead to grains of metal falling out of the tube or piping and being swept away by the process...

Authors: John Reynolds
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Superior inspection results, a best-in-class user interface, great ergonomics and rugged design, unrivaled connectivity options, and much more. The Krautkrämer USM 100 is a revolutionary ultrasonic flaw detector that uncomplicates your...

May/June 2004 Inspectioneering Journal

Chloride cracking of austenitic stainless steels (300 series SS) is an off-shoot of CUI, and there’s nothing really magical about it. If you have insulated solid stainless steel equipment operating in the CUI temperature range you are likely to...

Authors: John Reynolds
May/June 2004 Inspectioneering Journal

For purposes of this article, external (atmospheric) corrosion is what afflicts process equipment and structural members that are not insulated and exposed to moisture associated with atmospheric conditions, ie rain, condensation from humidity,...

Authors: John Reynolds
May/June 2004 Inspectioneering Journal

Soil corrosion (underground corrosion) is another one of those extensively researched and documented types of corrosion, since so many pipes and pipelines are buried and nearly all storage tanks rest on the soil. An entire industry/ technology is...

Authors: John Reynolds
May/June 2004 Inspectioneering Journal

CUI may be the most well known and widespread corrosion phenomena in our industry. It’s also one of the most difficult to prevent because by and large no matter what precautions we take, water eventually gets into the insulation and begins...

Authors: John Reynolds
March/April 2004 Inspectioneering Journal

API Recommended Practice 571, Damage Mechanisms Affecting Fixed Equipment in the Refining Industry

January/February 2004 Inspectioneering Journal

Casting defects are an age old problem for our industry that seems to be getting worse as foundries in the older industrialized world shutdown for economic reasons.

Authors: John Reynolds
January/February 2004 Inspectioneering Journal

Speaking of stress raisers, they are another insidious type of flaw that can and do lead to equipment failures. Stress raisers (aka stress intensification sites) can be mechanical or metallurgical notches. Undercutting, physical weld flaws,...

Authors: John Reynolds
January/February 2004 Inspectioneering Journal

When we specify that some equipment (vessels, flanges, fittings, etc.) be overlaid with a corrosion resistant alloy, we need to pay attention to making sure that the chemistry of the top layer of alloy welding, that will be exposed directly to...

January/February 2004 Inspectioneering Journal

DMW cracking is another fabrication issue that can and does result in equipment failure. It usually occurs at the weld juncture where carbon steel or low alloy steels are welded to austenitic (300 series) stainless steels in high temperature...

January/February 2004 Inspectioneering Journal

Cracks along the toe of a weld are not uncommon during fabrication, and can occur for a wide variety of reasons involving the metallurgy and process control of the the same issues covered above on repair welds can apply to repair welds on...

Authors: John Reynolds
November/December 2003 Inspectioneering Journal

Liquid Metal Cracking (LMC) (aka "liquid metal embrittlement") is another insidious form of cracking that strikes when you least expect it. It most commonly afflicts austenitic stainless steels, but can afflict other copper, nickel and aluminum...

Authors: John Reynolds
November/December 2003 Inspectioneering Journal

Carbonate cracking (CC) of carbon steel has seen an increase recently in frequency and severity in some refinery cat crackers, especially in fractionator and gas processing overheads. Some gas scrubbing units are also susceptible. CC is a form of...

Authors: John Reynolds
July/August 2003 Inspectioneering Journal

Thermal shock is another one of those pressure equipment afflictions where communication with operating groups is a vital factor in prevention. Thermal shock failures usually involve sudden quenching of high temperature equipment and furnace tubes...

Authors: John Reynolds
July/August 2003 Inspectioneering Journal

Cavitation is the sudden formation and immediate collapse of vapor or air bubbles in a liquid stream when system pressure falls below the vapor pressure of the liquid. The sudden collapse of these tiny bubbles generates enormous, though tiny forces...

Authors: John Reynolds
July/August 2003 Inspectioneering Journal

This is the name given to a form of embrittlement that occurs in 400 series of stainless steels, duplex SS's and less commonly in some 300 series stainless steels containing a metallurgical phase called ferrite. The embrittlement occurs from 600...

Authors: John Reynolds
July/August 2003 Inspectioneering Journal

This failure mechanism is unfortunately all too common in our industry. It's also known as stress rupture, and it is usually entirely preventable by proper maintenance and operating procedures. It occurs when equipment, piping or furnace tubes...

Authors: John Reynolds
January/February 2003 Inspectioneering Journal

Now you say, he's got to be putting me on. What is green rot? I didn't invent it. I first read about it in one of the early texts on corrosion engineering by Ughlig or Fontana, the venerable corrosion professors at MIT & Ohio State. But when I...

Authors: John Reynolds
January/February 2003 Inspectioneering Journal

I already mentioned this common affliction in the introduction. Caustic cracking was long called caustic embrittlement, but since no embrittlement actually occurs that name is fading away.

Authors: John Reynolds
January/February 2003 Inspectioneering Journal

Welcome to a new series of articles about the ninety-nine leading types of degradation, flaws and failure that can and do happen to pressure equipment in the hydrocarbon process industry.

Authors: John Reynolds
November/December 1996 Inspectioneering Journal

Petroleum coke production is an important source of revenue for many refineries. While coking units were initially constructed to deal with a waste product, these units are now of significant economic value.

November/December 1995 Inspectioneering Journal

Nelson Curve changes in the late 1980's provided cause for Shell Oil Company to look at more reliable NDE non-destructive evaluation methods for assessment of materials/equipment in high temperature hydrogen service. The primary change motivating...

    Videos related to Damage Mechanisms
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        Sponsored eBook

        This eBook offers practical guidance for, and real examples of, in-service degradation attributed to corrosion under insulation. It provides a detailed discussion on CUI detection, characterization and evaluation, and mitigation or remediation.

        Sponsored eBook

        This eBook offers practical guidance for, and real examples of, in-service degradation attributed to thermal fatigue. It provides a detailed discussion on thermal fatigue detection, characterization and evaluation, and mitigation or remediation.

        Sponsored Checklist

        This checklist serves as a companion piece to the Inspectioneering webinar, CUI: A Proactive Approach, and contains some elements to consider when looking for data gaps in your CUI program.

        Asset Intelligence Report

        This Asset Intelligence Report on Sulfidation Corrosion serves as a primer to increase your familiarity with one of the most well-known corrosion mechanisms in the oil refining industry.

        Asset Intelligence Report

        This Asset Intelligence Report on the hydrogen bake-out process serves as a primer to increase your familiarity with this technique used to drive hydrogen out of equipment prior to welding.

        Asset Intelligence Report

        Corrosion Under Insulation (CUI) is one of the most well-known damage mechanisms in the O&G and chemical processing industries, yet CUI still makes up a very large percentage of plant maintenance expenditures.

        Asset Intelligence Report

        This primer covers the fundamentals of High Temperature Hydrogen Attack (HTHA). Download and learn about this serious damage mechanism.

        eBook

        This publication outlines 101 Essential Elements that need to be in place and functioning well in order to effectively and efficiently preserve and protect the reliability and integrity of pressure equipment (i.e. vessels, exchangers, furnaces,...

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