News & View, Volume 48 | Fatigue Adjustment Factors for Increased Cyclic Life

News & Views, Volume 48 | Fatigue Adjustment Factors for Increased Cyclic Life

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By:  Bill WeitzeNews & View, Volume 48 | Fatigue Adjustment Factors for Increased Cyclic Life

100% of thermal stress was treated as nonlinear gradient stress and linear bending stress was about 12% of the moment stress. Structural Integrity’s (SI’s) review of the stress terms used in piping analysis show that pressure stress does create bending stress in components…

EPRI Report 3002014121 “Development of Fatigue Usage Life and Gradient Factors” has developed fatigue usage adjustment factors that account for: 1) increased cyclic life associated with the growth of potential engineering size fatigue cracks in thicker components (thickness factor, TF; also called life factor, LF), and 2) the presence of through-thickness stress gradients (gradient factor, GF). (TF is used in the issued Code Case.)  These factors are applied to cumulative usage factor, U, in air.

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News & View, Volume 48 | Examination Optimization for PWR and BWR Components

News & Views, Volume 48 | Examination Optimization for PWR and BWR Components

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By:  Scott Chesworth, Bob Grizzi, and Dilip Dedhia

Optimizing the inspection interval for high-reliability components whose examinations have a significant outage impact.News & View, Volume 48 | Examination Optimization for PWR and BWR Components

Welds and similar components in nuclear power plants are subject to periodic examination under ASME Code, Section XI.  Typically, examinations are performed during every ten-year inspection interval using volumetric examination techniques, or a combination of volumetric and surface examination techniques.  Nuclear plants worldwide have performed numerous such inspections over the plant history with few service induced flaws identified.  Since personnel health and safety, radiation exposure, and overall outage costs associated with these inspections can be significant, Structural Integrity (SI) was contracted by the Electric Power Research Institute (EPRI) to review the technical bases for the inspection intervals for select components.  The goal was to determine whether the frequency of current inspection requirements was justified or could be optimized (i.e., reduced in order to devote more attention to higher-value inspections and thereby maximize overall plant safety).  Special priority was given to components demonstrating an exceptional history of reliability and whose examinations have a significant outage impact.

News & Views, Volume 48 | Environmentally-Assisted Fatigue Screening and Managing EAF Effects in Class 1 Reactor Coolant Components

News & Views, Volume 48 | Environmentally-Assisted Fatigue – Screening and Managing EAF Effects in Class 1 Reactor Coolant Components

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By: Dave Gerber and Terry HerrmannNews & Views, Volume 48 | Environmentally-Assisted Fatigue Screening and Managing EAF Effects in Class 1 Reactor Coolant Components

Environmentally-Assisted Fatigue (EAF) screening is used to systematically identify limiting locations for managing EAF effects on Class 1 reactor coolant pressure boundary components wetted by primary coolant.  This article provides an overview of the methods developed and used by Structural Integrity (SI) for Class 1 components having explicit fatigue analyses performed using ANSI/ASME B31.7(1) and ASME Section III(2).  A future article will discuss how this is performed for Class 1 piping designed and analyzed to ASME/ANSI B31.1(3).

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News & View, Volume 48 | SI-FatiguePro Version 4.0 Crack Growth Module Application Case Study; Complex Multi-Cycle Nuclear Transients

News & Views, Volume 48 | SI:FatiguePro Version 4.0 Crack Growth Module – Application Case Study Complex Multi-Cycle Nuclear Transients

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News & View, Volume 48 | SI-FatiguePro Version 4.0 Crack Growth Module Application Case Study; Complex Multi-Cycle Nuclear Transients

By: Curt Carney

As plants enter their initial or subsequent license renewal period one of the requirements is to show that fatigue (including environmental effects) is adequately managed.  For some locations in pressurized water reactors (PWRs), it can be difficult to demonstrate an environmental fatigue usage factor less than the code allowable value of 1.0.  Therefore, plants are increasingly turning to flaw tolerance evaluations using the rules of the ASME Code, Section XI, Appendix L.  Appendix L analytically determines an inspection interval based on the time it takes for a postulated flaw (axial or circumferential) to grow to the allowable flaw size.  For surge line locations, this evaluation can be very complex, as the crack growth assessment must consider many loadings, such as: insurge/outsurge effects, thermal stratification in the horizontal section of the line, thermal expansion of the piping (including anchor movements), and internal pressure.  Trying to envelope all of these loads using traditional tools can lead to excess conservatism in the evaluation, and short inspection intervals that reduce the value of an Appendix L evaluation.

News & Views, Volume 48 | Metallurgical Lab Case Study – Grade 91 Elbows Cracked Before Installation

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By:  Wendy Weiss and Terry Totemeier

News & View, Volume 48 | Metallurgical Lab Case Study - Grade 91 Elbows Cracked Before InstallationStructural Integrity (SI) personnel visited a power plant construction site to examine four Grade 91 elbows (ASTM A234-WP91 20-inch OD Sch. 60) that were found to contain axially oriented surface indications. The elbows had not yet been installed. The indications were initially noticed during magnetic particle testing (MT) after one end of an elbow was field welded to a straight section and post weld heat treated (PWHT). Subsequently, three additional similarly welded elbows were inspected and indications were found at both the welded (inlet) and open (outlet) ends of three elbows. The elbow with the most significant indications was selected for SI’s on-site examinations. Figure 1 shows the inlet and outlet ends of the selected elbow.

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News & View, Volume 48 | Bypass Line Spray Issues

News & Views, Volume 48 | Bypass Line Spray Issues

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News & View, Volume 48 | Bypass Line Spray IssuesBy:  Ben Ruchte and Kane Riggenbach

To provide operating flexibility, combined cycle plants are typically equipped with bypass systems (high pressure routing steam to cold reheat and hot reheat routing steam to the condenser).  These bypass systems include conditioning valves designed to reduce steam pressures followed by outlet desuperheaters which inject water to reduce steam temperatures.

This service environment exposes the downstream piping to a high frequency of temperature transients making these areas one of the most prominent ‘industry issues’.

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News & View, Volume 48 | Considerations of Pin Cracking in Finger Pin Turbine Blade Attachments

News & Views, Volume 48 | Considerations of Pin Cracking in Finger Pin Turbine Blade Attachments

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By:  Cliff Lange and Matt Freeman

OEMs recommend periodic inspection of pinned finger turbine blade attachments for detection of service-induced damage as part of ongoing rotor maintenance activity. 

This article provides an example where ultrasonic inspection detected cracking in several pins of finger attachments and outlines an engineering assessment to support continued operation and identify a re-inspection interval.  This approach can be applied to other pinned finger blade attachments to determine suitability for service.

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News & View, Volume 48 | SI Field Service Quality and Efficiency Solutions

News & Views, Volume 48 | SI Field Service Quality and Efficiency Solutions

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By:  Robert Chambers and Trey RippyNews & View, Volume 48 | SI Field Service Quality and Efficiency Solutions

To help meet demanding outage schedules and stay within lean operation and maintenance budgets, Structural Integrity Associates, Inc. (SI) has implemented several new field data collection and analysis tools that enable delivery of a higher-quality final inspection product in a more efficient manner. These include customized software tools for streamlining the NDE data acquisition, analysis, and reporting processes. Moving forward, these tools will reduce time-on-pipe for inspections, as well as the associated analysis and reporting time.

For large inspection scopes, collecting, tagging, managing, transferring, and documenting data can be a very labor-intensive process with opportunities for human performance errors. While inspection instruments and analysis software typically have built-in reporting capabilities, these tend to be very general so they can be applied to a wide variety of applications. This can make it cumbersome to tailor these features to a specific application.

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News & View, Volume 48 | Post Seismic Certification - What Do Manufacturers Do to Keep Their Products TRU Listed?

News & Views, Volume 48 | Post Seismic Certification: What Do Manufacturers Do to Keep Their Products TRU Listed?

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By:  Galen Reid and Katie Braman How does TRU or the public know the manufacturer is continuing to produce a product that complies with the certified construction and configuration without retesting periodically? Certification of products to withstand extreme event loading can open many opportunities for manufacturers to sell high value products when others have a […]

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News & View, Volume 48 | SI Supports Parsons' “DetectWise Modular COVID Test Facility

News & Views, Volume 48 | SI Supports Parsons’ “DetectWise” Modular COVID Test Facility

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By:  Zach Withall and Matthew Naugle, PENews & View, Volume 48 | SI Supports Parsons' “DetectWise Modular COVID Test Facility

The health facility is designed to fully separate patients from medical workers, protecting both parties and minimizing the PPE required to operate the suite.

COVID-19 has presented humanity with unprecedented challenges.  As economies reopen, solutions are needed that allow businesses to operate while protecting the health, safety, and security of the general public.

In an effort to positively impact that change, Structural Integrity Associates (SI) is working with Parsons Corporation, a global technology leader, to design a self-contained, mobile health screening facility for rapid, efficient and scalable testing.

The mobile facility is part of Parsons’ DetectWise™ suite of health solutions meant to combat the COVID-19 pandemic. SI provided structural design services for the facility.

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