In cases where material embrittlement caused by hydrogen is a concern, evaluations using fracture mechanics to assess the reliability and integrity of steel pipes exposed to cyclic loads are necessary.

There are many excellent changes and updates in the new edition of API 579, including significant technical changes and improvements. In this FFS Forum article, I’ll go through many of what I believe to be the most important changes.

This issue of Damage Control offers a perspective on how to assess the different forms of wet H2S damage using modern FFS and computational analysis techniques with the safe operation of damaged pressure vessels, piping, and associated components.

This follow-up article discusses the important topic of establishing Heat Exposure Zones and Level 1, 2, and 3 fitness-for-service assessments following a plant fire.

Part 1 presents a brief overview of the process of assessing equipment in a post-fire "return-to-service" effort and discusses some common issues that may arise during that process.

Our proprietary furnace tube inspection system, FTIS is an ultrasonic inspection technology capable of rapid, automated fired heater coil inspection in refinery fired heaters. The data captured by our furnace tube inspection system is...

This article addresses some of the advantages and disadvantages of acoustic emission testing and discusses a few examples of its typical applications.

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

Globally accepted FFS procedures for non-metallic components, such as reinforced thermoplastic pipes, do not exist. There may be opportunity in adapting existing procedures for metallic components and their damage mechanisms to composite components.

FFS assessments usually originate from inspection results and often end with a recommended inspection plan. This FFS Forum tries to provide a little better understanding of one particular inspection method: Acoustic Emission Testing.

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.

InVista is a lightweight, hand-held ultrasonic in-line inspection tool (intelligent pig) capable of detecting pipeline wall loss and corrosion in unpiggable or difficult-to-inspect pipelines. The pipeline geometry inspection data captured by the...

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.

Conventionally, three primary fatigue analysis methods have been used to estimate fatigue life; these are the stress-life (S-N) approach, the strain-life (ε-N) approach, and the fracture mechanics (crack growth) approach.

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.

Fracture mechanics is a branch of engineering that describes the behavior of cracks – how they grow and when they fracture. Fracture of cracks is particularly dangerous because it can happen without warning under normal operating conditions.

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?

AET is a powerful, non-intrusive inspection technique to verify the structural integrity of pressure vessels, spheres, high-temperature reactors and piping, coke drums, above-ground storage tanks, cryogenic storage tanks, and more.

This article provides an overview of brittle fracture, details on several industry failures, and a summary of deficiencies and concerns with current published methods for screening susceptibility of equipment to potential brittle fracture failures.

There are many places where brittle fracture risk can sneak into your plant and many reasons why a new or revised brittle fracture assessment may be required when reviewing your pressure systems. Don’t overlook this dangerous failure mechanism.

FMR is a useful tool in many situations. It allows nondestructive evaluation of the surface microstructure that is entirely adequate in many cases. However, it is not a panacea, and there are many conditions where it is inadequate.

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.

A cornerstone of Level 1 and 2 metal loss assessment methods in API 579 is the concept of measuring thickness on a grid and constructing a “critical thickness profile.” These concepts are fundamental to Level 1 & 2 assessments in both Parts 4...

Auto-refrigeration can impose low temperatures onto process vessels and piping causing them to be at risk of brittle fracture, the sudden break-before leak phenomena that can result in catastrophic rupture of the equipment.

MSDs are an important, but often misunderstood, element of FFS analyses. This column will help readers understand what an MSD is and why it is so important to Fitness-For-Service analysis under API 579.

This is the second of a two-part column on “Creep.” This second part discusses the approach to creep assessment in plant equipment.

This blog article provides examples on addressing widely scattered pitting through the performance of a fitness-for-service assessment using the three conditions set out in the API 510 Pressure Vessel Inspection Code.

This is the first of a two-part column on “Creep”. It presents an engineering overview of the phenomena, answers the question: “What is Creep?”, and provides readers with foundational knowledge for evaluating and managing remaining...

Brittle fracture and material toughness issues are important concerns in equipment design and FFS. These issues increase when temporary start-up and shutdown conditions require more detailed assessments than provided for in vessel and piping codes.

FFS assessment techniques are applicable to a wide range of damage types: LTA's, cracks, creep damage, dents, and more. These are very powerful analytical tools that often allow operators to not only keep the plant running, but to keep it running...

The distinction between primary and secondary loads is certainly important in analysis of pressure systems. But this distinction is also important for plant operations and reliability engineers to keep in mind when dealing with day-to-day problems.

An effective RBI system implementation results in, not only safeguarding your assets & people, but can also reduce unnecessary inspection activities that may be required due to conventional & nonsystematic approaches.

In this edition of the FFS Forum, Greg addresses some issues associated with inspection of vessels that have been in service for a number of decades, and offers some tips for reliability and inspection to follow when inspecting these older vessels.

In this column, I touch on what I see as an underused FFS technique for corrosion assessment: point assessment of corrosion – a technique that does NOT require a thickness grid. The reason I find this technique useful is largely because it’s...

API 579-1 is a complex document covering several different types of equipment that may contain flaws or damage. Due to its complexity, this article condenses it into six things you need to know.

Equity Engineering Practices® (EEPs) are a collection of detailed & customizable Best Practices integrated with a customizable management system. EEPs include: 650+ branded and customizable Best Practice Documents, 225+ Pre-Engineered &...

With no industry consensus documents in existence that provide guidance for determining FFS of FRP, this article provides a case study that illustrates how an existing European design standard on GRP tanks can be used to calculate expected changes...

This article details the experience an oil company had when using FEA to evaluate the implications of a damaged pipeline. Specifically, it presents an efficient method that combines analytical techniques with FEA to determine the pipeline’s...

There is concern in the industry over recent findings of reduced toughness fittings and flanges at risk of brittle fracture. This article provides an overview; possible contributors; measures taken to address; and a proposed FFS approach to address...

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...

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.

Training options to meet your needs. E²G contracts with API to deliver training programs for FFS, Risk–Based Inspection, Damage Mechanisms, and Pressure Relieving Systems. ETI and Customized Training offers specialized courses based on industry...

Due to its high-cost, Level 3 FFS is typically carried out after Levels 1 or 2 and only in extreme cases. However, advancements in inspection technology and improved use of inspection data have made Level 3 analysis more practical and affordable,...

This article will go through the methodology of each process that could be used in determining the structural component for the required pipe wall thickness, but will focus on the use of Beam Flexural Stress calculations and Beam Deflection...

This article exhibits how modern inspection methodologies combined with innovative computational analysis practices demonstrate the value of conducting fitness-for-service (FFS) assessments on sectional piping.

Aging equipment, along with more aggressive service, makes it more important than ever to carry out fitness-for-service (FFS) assessments in support of run/repair/replace decisions. Testing material in the service-degraded condition enables...

Achieving fired heater reliability in conjunction with meeting performance standards can be a challenging feat. Performance is a measure of the degree to which the fired heater is in an operable condition at any given time.

What do you need: CONSULTING - Subject matter experts, consultants, or team of highly skilled engineers to help solve my problem. SOFTWARE - My team requires software, products, or resources that will solve the problem. TRAINING - I require...

To ensure the mechanical integrity and fitness-for-service (FFS) of equipment, facility managers, reliability engineers, and inspection technicians must understand the HTHA damage mechanism.

Asset managers need to know when repairs and replacement are required for many reasons, including safe operation, accurate budgeting, replacement planning, and on-going reliability. When predicting design life based on a simple, linear corrosion...

This article introduces portions of a “Best-In-Class” Fitness-for-Service (FFS) program that includes the performance of regular visual inspections of pipe supports and hangers, coupled with in-situ load testing of suspect supports. This...

In recent years, the growing use of composite repair systems for the rehabilitation of piping systems in the refining and chemical industries has increased the need for associated technologies for their manufacturing, installation, and inspection....

For many years, it has been common practice in the petrochemical industry to use fitness-for-service (FFS) evaluations to determine whether or not a finding during an inspection would prevent a part from being able to be returned to service.

Are you truly prepared for your next Turnaround? Effective work processes are required to successfully plan, manage, review and supervise plant turnarounds. Inspection planning and work scope selection are critical aspects of any turnaround...

There are numerous benefits to adding fitness-for-service (FFS) assessments to energy sector reliability projects. The acceptance of API 579/ASME FFS-1 is increasing across the energy sector and other industries, as these benefits have been...

One of Inspectioneering's most popular topics is Fitness for Service (FFS). This blog post will provide you with some highlights from some of our most popular articles related to FFS. It's only a small sample of what we offer, but it should still...

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...

As an RBI consultant, I frequently get involved in discussions spawned from a misunderstanding of the relation between Risk Based Inspection (RBI) approaches and Fitness for Service (FFS) assessments. Questions like: If thickness is below the...

Inspections, repairs, modifications, or Fitness-For-Service (FFS) assessments on an old, unfired ASME Section VIII (Div. 1) pressure vessel - Which ASME Section VIII (Div. 1) Code Edition should you use?

Inspectioneering and API have teamed up to create the Mechanical Integrity Professional Initiative. The goal of this project is to raise the benchmark on industry knowledge and develop the next generation of SMEs. We believe that equipping MI...

Since important decisions will be based on the results of the fitness-for-service (FFS) determination, you need to be sure that you have a strong FFS team. But what are the key ingredients of a good FFS team? This article provides some guidelines to...

Fired furnaces in the petrochemical and refining industry are critical pieces of equipment that can have a major impact on process unit safety, reliability, and economics. They are complex pieces of equipment, where tubes and other pressure boundary...

While there are many types of damage mechanisms that can occur in a piece of equipment, localized metal loss is one of the most common. If an inspection reveals that metal loss has occurred, many questions are raised...

Auto-refrigeration is a process where an unintentional and/or uncontrolled phase change of a hydrocarbon from a liquid state to a vapor occurs, resulting in a very rapid chilling (refrigeration) of the liquid containing local equipment and/or...

Even though oil and gas pipelines and their related facilities are generally safer for people and the environment compared to other means of transportation, occasional leaks and failures due to corrosion and other defects have become an issue in...

In this interim report, Pinnacle analysts take data from the oil refining industry and dive into how that key sector is being affected by reliability today. Download your free copy!

We’ve been discussing Scalable Accuracy and its use related to Lifecycle Management technologies available to owner/operators. The last few topics have included Risk Based Inspection, Fitness for Service using Accuracy, the approach for Equipment...

This blog post continues our discussion from the previous posts on scalable accuracy. We started with a post outlining the steps prior to using scalable accuracy. Then we walked through the scalable accuracy approach to Fixed Equipment LCM. While I...

Continuing from last week’s blog, I want to go in depth into scalable accuracy for fixed equipment lifecycle management. In this post, I want to outline the scalable accuracy approach to fixed equipment lifecycle management.

In the next few blog posts, we will be going in depth on scalable accuracy. This post walks through the thinking needed prior to initiating. Then we will discuss two technologies immediately available to plant operators for fixed equipment...

Inspection and fitness-for-service assessments of critical in-plant piping systems are a concern for the chemical industry. This presents a potentially insurmountable task and discovery of a number of areas where the condition is at risk.

Download Pinnacle's Economics of Reliability Report - Refining to see how reliability is affecting profitability.

This is my second of three posts on Key Performance Indicators (KPIs) based on requests and discussions on the issue.  In part 1 of this series I provided a brief overview of KPIs and their ability to predict good, poor, and sometimes...

This is a question with which I frequently like to start the API RBI 580/581 training course when I am instructing. It is meant to provoke the attendees to really think hard about why they order an inspection or really think about inspection...

If an operator finds cracking in a furnace waste heat boiler, excessive thinning in an absorption tower, or severe bulging in a converter, FFS assessments—not standard code analyses—are needed to evaluate the unit’s mechanical...

The benefits of adding fitness-for-service (FFS) assessments to energy sector reliability projects are numerous. The acceptance of API 579/ASME FFS-1 is increasing across the energy sector and other industries, as these benefits have been...

An all too familiar scenario in power plants is one in which an inspection finding occurs late in an outage and consequently, the return to service date may need to be postponed to allow time for corrective action. Historically, cracks or thinned...

Traditional pressure vessel inspections often require taking assets out of service. However, MISTRAS’ Non-Intrusive Inspection (NII) programs provide data as good or better than internal inspections, while assets remain in service. NII is...

Thanks to constantly improving technology developments, inspection of atmospheric storage tanks has yielded better data which, when used as input, improves the accuracy of advanced assessment techniques. Coupling the improved inspection data with an...

The various factors of the challenge, e.g. creating effective and then efficient inspection strategies, are at the crux of the decision process. Within each of these factors are questions that must be answered. The answers should be well thought...

The design and fabrication of nuclear pressure vessels and piping components are governed by the rules of Section III of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code. This Code, which aims to to ensure high...

The original article on scalable accuracy which laid the groundwork for the concept was published in the March April 2011 issue of the Inspectioneering Journal, entitled Scalable Accuracy, Key Roles of Risk Based Inspection and Fitness for Service,...

Two technologies, immediately available to plant operators for fixed equipment life-cycle management are Risk-Based Inspection (RBI) and Fitness for Service (FFS), two best practices that optimally work together or can standalone. Both have...

The OmniScan X3 flaw detector is a complete phased array toolbox. Powerful tools, like total focusing method (TFM) images and advanced visualization capabilities, enable you to complete your inspection with greater confidence.

In the first article in this series entitled How to Put It All Together - Guide to Organizing a Successful PEI Program, (1) I provided an overview of the necessary Management Systems (MS) for a successful program to achieve excellence in pressure...

Understanding, predicting, detecting and controlling high-temperature hydrogen attack (HTHA), have been elusive goals of materials engineers and scientists for over 70 years. The destruction of low alloy steel components exposed to hydrogen through...

In the oil and gas industry, pressure vessel integrity is a major concern. After internal and external inspections various anomalies or defects can be reported and repairs could be required for pressure vessels in order to restore its original...

The assessment procedures in this Standard can be used for Fitness-For-Service assessments and/or re-rating of equipment designed and constructed to recognized codes and standards, including international and internal corporate standards.

This is part 2 in a multi-part series. Part 1 set the stage in explaining the basics of RBI. As I am most familiar with API Base Resource Document 581, I will continue to use this technical basis for this article.

Revisions to the California Code of Regulations Title 8 Petroleum Safety Orders are nearly complete and the new regulations should be published late summer 2006. The regulations will affect both drilling and production facilities and refining,...

A few years ago, TWI investigated a corrosion failure in a 30 inch crude oil pipeline that regrettably led to an explosion and fire, and the death of several operating personnel. The pipeline was designed to ASME B31.4 and the investigation found...

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...

API is preparing to release the next edition of API 579 Fitness-For-Service (FFS) the first quarter of 2006. The many major enhancements that have been made to the next edition of API 579 will permit Owner-Users to evaluate new types of damage...

We are happy to announce the 10-year anniversary of the inaugural issue of the Inspectioneering Journal!

The number of FFS assessments carried out by inspection engineers is expected to increase in the future, as operators "sweat" their ageing process equipment. The parameters required for assessments can be quite complex and interdependent. Therefore,...

Several new API inspection recommended practices exist in which inspectors need to be knowledgeable and qualified. This article details some of those standards.

The following is the final part of a 2-part series outlining the relationship between key operating parameters and corrosion that has been used to develop a set of guidelines to define an operating envelope.

We have discussed various factors that can affect the reliability of NDE techniques (i.e., probability of detection - POD and sizing accuracy) in Part 1. In general, it is difficult to quantify these uncertainties. In fact, it is impossible to fully...

Safety, environmental and economic pressures are motivating process industry (e.g. refineries & petrochemical plants) operators to consistently improve equipment reliability performance, optimize expenses and more accurately target resources where...

A typical risk based inspection (RBI) analysis should include past inspection results, tempered by confidence in those results. For example, API's (American Petroleum Institute) RBI methodology and software when calculating the likelihood of failure...

The use of engineering critical assessment (ECA)of "fitness for service", for the evaluation of flaws and local wall thinning in pressure vessels is receiving a lot of attention in the petrochemical and utility industries. A rigorous methodology...

With the publication of API RP 579 For Fitness-For-Service and the planned publication of API RP 580 for Risk Based Inspection in 2001, these technologies will find increasing application in maintenance and inspection planning.

Part 4 of this article continues to outline the 101 essential elements that need to be in place, and functioning well, to effectively and efficiently, preserve and protect the reliability and integrity of pressure equipment (vessels, exchangers,...

The release of API RP579 will bring about some changes to other existing API standards. The plan is to offer an integrated suite of API standards, where information is presented once and the other documents refer and are linked to that information.

The U.S. Department of Energy's Idaho National Engineering Laboratory (INEL) has a substantial interest in predictions for fitness-for-service as well as for lifetime extension. The ability to predict fitness-for-service is applicable to making...

An inescapable law of nature is that engineering materials contain flaws. Perfect materials and welds simply do not exist in the real world. A newly fabricated pressure vessel, for example, contains numerous imperfections and will probably degrade...

Evaluations of aged and critical service vessels such as FCCU's and Delayed Cokers have been aided by the addition of two physical measurements referred to as structural characterizations. These are placed in perspective with the classic...