Managing the Threat of Selective Seam Weld Corrosion Using a State of the Art Ili System

2021 ◽  
Author(s):  
Simon Slater ◽  
Chris Davies
Keyword(s):  
State Of The Art ◽  
Seam Weld ◽  
Weld Corrosion

Development of Selective Seam Weld Corrosion Test Method

2014 ◽  
Author(s):  
J. A. Beavers ◽  
C. S. Brossia ◽  
R. A. Denzine
Keyword(s):  
Base Metal ◽  
Field Testing ◽  
Test Method ◽  
Transportation Safety ◽  
Seam Weld ◽  
Corrosion Kinetics ◽  
Pipeline Failures ◽  
Weld Corrosion ◽  
Pipeline Safety ◽  
Non Destructive

Selective seam weld corrosion (SSWC) of electric resistance welded (ERW) pipelines has been identified as a potential risk to pipeline safety. Due to recent pipeline failures, where seam weld defects may have played a significant role, the National Transportation Safety Board called upon the Pipeline and Hazardous Materials Safety Administration (PHMSA) to conduct a comprehensive study to identify actions that can be used by operators to eliminate catastrophic longitudinal seam failures in pipelines. Battelle contracted Kiefner and Associates, Inc. and Det Norse Veritas (U.S.A.) Inc. (DNV GL) with the objective to assist PHMSA in addressing this issue. The objective of one of the tasks performed by DNV GL was to develop a reliable, rapid, non-destructive, field-deployable test method that can quantify SSWC susceptibility on operating pipelines containing ERW seams. For this effort, two different, field deployable, non-destructive methods were evaluated in laboratory testing. The methods were validated using a standard destructive test for assessing SSWC susceptibility. One method was based on measurement of the local potential difference between the seam weld and the adjacent base metal while the second was based on differences in the corrosion kinetics between the seam weld and the base metal. The method that is based on corrosion kinetics was found to be most effective in identifying SSWC susceptible pipe steels. It utilizes a barnacle cell to conduct linear polarization resistance measurements on small, selected areas of the pipe (e.g., the weldment or base metal). Additional laboratory as well as field-testing is planned to further validate the test method.

New Classification Approach for Dents With Metal Loss and Corrosion Along the Seam Weld

2016 ◽  
Author(s):  
J. Bruce Nestleroth ◽  
James Simek ◽  
Jed Ludlow
Keyword(s):  
Magnetic Field ◽  
Low Frequency ◽  
Metal Loss ◽  
Integrity Assessment ◽  
Seam Weld ◽  
Low Field ◽  
Electric Resistance Welding ◽  
Weld Corrosion ◽  
Pipeline Safety

The ability to characterize metal loss and gouging associated with dents and the identification of corrosion type near the longitudinal seam are two of the remaining obstacles with in-line inspection (ILI) integrity assessment of metal loss defects. The difficulty with denting is that secondary features of corrosion and gouging present very different safety and serviceability scenarios; corrosion in a dent is often not very severe while metal loss caused by gouging can be quite severe. Selective seam weld corrosion (SSWC) along older low frequency electric resistance welding (ERW) seams also presents two different integrity scenarios; the ILI tool must differentiate the more serious SSWC condition from the less severe conventional corrosion which just happens to be near a low frequency ERW seam. Both of these cases involve identification difficulties that require improved classification of the anomalies by ILI to enhance pipeline safety. In this paper, two new classifiers are presented for magnetic flux leakage (MFL) tools since this rugged technology is commonly used by pipeline operators for integrity assessments. The new classifier that distinguishes dents with gouges from dents with corrosion or smooth dents uses a high and low magnetization level approach combined with a new method for analyzing the signals. In this classifier, detection of any gouge signal is paramount; the conservatism of the classifier ensures reliable identification of gouges can be achieved. In addition to the high and low field data, the classifier uses the number of distinct metal loss signatures at the dent, the estimated maximum metal loss depth, and the location of metal loss signatures relative to dent profile (e.g. Apex, Shoulder). The new classifier that distinguishes SSWC from corrosion near the longitudinal weld uses two orientations of the magnetic field, the traditional axial field and a helical magnetic field. In this classifier, detection of any long narrow metal loss is paramount; the conservatism of the classifier ensures that high identification of SSWC can be achieved. The relative amplitude of the corrosion signal for the two magnetization directions is an important characteristic, along with length and width measures of the corrosion features. These models were developed using ILI data from pipeline anomalies identified during actual inspections. Inspection measurements from excavations as well as pipe removed from service for lab analysis and pressure testing were used to confirm the results.

Overview of a Comprehensive Study to Understand Longitudinal ERW Seam Failures

2014 ◽  
Author(s):  
Bruce A. Young ◽  
Steve Nanney ◽  
Brian Leis ◽  
Jennifer M. Smith
Keyword(s):  
Phase I ◽  
Management Practices ◽  
Structural Integrity ◽  
Experimental Studies ◽  
Current Approach ◽  
Transportation Safety ◽  
Seam Weld ◽  
Integrity Management ◽  
Weld Corrosion ◽  
Comprehensive Study

In response to the National Transportation Safety Board (NTSB) Recommendation P-09-1, the Department of Transportation (DOT) Pipeline and Hazardous Material Safety Administration (PHMSA) initiated a comprehensive study to identify actions that could be implemented by pipeline operators to eliminate longitudinal seam failures in electric resistance weld (ERW) pipe. This study was contracted with Battelle, working with Kiefner and Associates (KAI) and Det Norske Veritas (DNV) as subcontractors. The purpose of this paper is to provide an overview of the project with focus on the study objectives, results, and on-going work. Phase I of the project consisted of four major tasks aimed at understanding the current state of the issues. Task 1 analyzed the databases gathered and qualified in five interim reports that dealt with 1) the failure history of vintage ERW seams, including flash-weld (FW) pipe and selective seam-weld corrosion (SSWC); documented in two subtask 1.4 reports, 2) the effectiveness of in-line inspection (ILI) and hydrotesting, and experience with predictive modeling, documented in subtask reports 1.2 and 1.3 and 3) literature concerning SSWC documented in subtask 1.5 report. Task 2 addressed experimental studies designed to better characterize the failure of ERW/FW seams and quantify the resistance of such seams (Subtask 2.1–2.3 and 2.6 reports) and their response to pressure (Subtask 2.4 and 2.5 reports). Task 3 considered aspects related to SSWC with four separate reports from subtask 3.1–3.4. Task 4 focused on integration of the other tasks, trending, and analysis. Phase II has been initiated and consists of five tasks with the following objectives relevant to the ERW and FW process: 1) develop and optimize viable hydrotest protocols for ERW/FW seam defects 2) improve the sensors, interpretive algorithms, and tool platforms in regard to ILI and In-the-Ditch-Methods (ITDM) to better ensure structural integrity with optimized detection and sizing, 3) bridge gaps in defect characterization in regard to types, sizes, shapes, and idealizations. The goal of this subtask is to increase pipeline safety through improvements in the tools needed to implement both ILI and hydrotesting, 4) validate existing models and, where gaps preclude validation, refine or develop models needed to assess and quantify defect severity for cold welds, hook cracks, and selective seam weld corrosion (SSWC) (the primary threats) for failure subject to loadings that develop both during hydrotests and in service, and 5) develop a digitally based framework to support integrity management of seam welds with enough flexibility to benefit from the experience embedded in the stopgap protocol. To date, this study has led to seventeen (17) reports. These publically available reports are located on the PHMSA website: http://primis.phmsa.dot.gov/matrix/PrjHome.rdm?prj=390. Based on the work completed during Phase I, gaps identified in the context of the NTSB Recommendation P-09-1 were supported by the historic records. Additionally, recent improvements in related technologies and integrity management practices point to the practical utility and viability of PHMSA’s current approach to manage the integrity of the U.S. pipeline.

Types of Defects That Affect ERW Seam Integrity in Response to NTSB Recommendation P-09-1, Arising From the Carmichael, MS Rupture

2014 ◽  
Author(s):  
J. F. Kiefner ◽  
J. B. Nestleroth ◽  
G. T. Quickel ◽  
J. A. Beavers ◽  
B. N. Leis
Keyword(s):  
Low Frequency ◽  
Manufacturing Defects ◽  
Integrity Assessment ◽  
Seam Weld ◽  
Stress Cracking ◽  
Service Failures ◽  
Sulfide Stress ◽  
Welded Seam ◽  
Weld Corrosion ◽  
Made In

The types of defects that have caused in-service failures and hydrostatic test failures of natural gas and hazardous liquid pipelines comprised of electric resistance welded (ERW) or flash-welded seams were revealed by a study of 569 seam failure incidents that occurred over a period from the 1940s through the present. This study confirmed that ERW and flash-welded seam manufacturing defects, such as cold welds (lack of fusion) and hook cracks, are frequent causes of hydrostatic test failures. Causes of in-service failures included cold welds, hook cracks enlarged by fatigue, other manufacturing defects enlarged by fatigue, selective seam weld corrosion, hydrogen stress cracking, sulfide stress cracking, and stress corrosion cracking (SCC). An important finding with respect to low-frequency-welded ERW and flash-welded materials was that defects in the bond lines of such materials (e.g., cold welds, selective seam weld corrosion) sometimes failed at much lower stress levels than one would predict based on the toughness of the parent metal. This fact complicates seam integrity assessment by means of in line inspection (ILI) because toughness is needed to prioritize anomalies for examination, and the toughnesses of the bond lines of most pipelines are not known. The findings suggest that conservative assumptions may have to be made in order for a pipeline operator to have confidence in a seam integrity assessment by means of ILI even if the ILI technology accurately characterizes the anomalies.

Managing the Threat of Selective Seam Weld Corrosion Using a State of the Art ILI System

2020 ◽  
Author(s):  
Christopher Davies ◽  
Simon Slater ◽  
Christoper De Leon
Keyword(s):  
Material Properties ◽  
Weld Zone ◽  
Evaluation Process ◽  
Management Plan ◽  
Management Approach ◽  
Metal Loss ◽  
Integrity Assessment ◽  
Seam Weld ◽  
Integrity Management ◽  
Weld Corrosion

Abstract For many years, pipeline safety regulations in the US have defined prescriptive minimum requirements for integrity management combined with a clear expectation that operators should do more than the minimum where appropriate. The regulations have also provided operators with the flexibility to take a performance based integrity management approach leveraging as much information available to manage threats effectively. One the threats that must be managed is Selective Seam Weld Corrosion (SSWC). SSWC is an environmentally assisted mechanism in which there is increased degree of metal loss in the longitudinal weld in comparison to the surrounding pipe body. An appropriate definition is linear corrosion that is deeper in the longitudinal weld zone than the surrounding pipe body. In some cases, the surrounding pipe body may have limited or no corrosion present, and in other cases the pipe body corrosion may have occurred but at a slower rate than the local corrosion in the longitudinal weld zone. Conventional responses to potential or identified threats focus on in-situ investigations, often resulting in expensive and un-planned repairs for features reported by In-line Inspection (ILI) that when assessed properly demonstrate a remnant life well into the next inspection interval. When ILI identifies metal loss indications co-located with the longitudinal seam weld, the current prescribed response is often a blanket call for remediation. Such a response may not be appropriate if an ILI system is deployed to discriminate feature types and integrity assessment is exercised leveraging a sound understanding of the pipe’s material properties. This paper describes an approach that can be taken to manage the threat of SSWC. The foundation of the approach is deployment of an appropriate ILI system incorporating an effective ILI technology, an optimized evaluation process considering the specific threat morphology, material testing and a structured dig program. The evaluation process uses the ILI data and data from the field in combination material properties data and a susceptibility analysis to classify anomalies as “Likely”, “Possible” and “Unlikely” SSWC. This is aligned with the guidance in API RP 1176 “Assessment and Management of Cracking in Pipelines” for defining an appropriate response to ILI calls. Approaching the management of SSWC in this way allows operators to define a structured response for excavation activities to verify the process and remediate features as required. By using likelihood classification the risk to pipeline integrity can be reduced by acting on the most likely SSWC features as a priority, whilst collecting the data needed to make informed decisions on where to focus resources and efforts on what is a very complicated and difficult to manage threat. The output form this work, including a future plan for managing the remaining metal loss features, can be documented in a procedure and incorporated into an existing Integrity Management Plan.

Practical Picture Processing

1974 ◽  
Vol 32 ◽  
pp. 338-339
Author(s):  
T. A. Welton
Keyword(s):  
Radiation Damage ◽  
Coherence Length ◽  
Spatial Information ◽  
State Of The Art ◽  
Coherent Radiation ◽  
The State ◽  
Energy Spread ◽  
Electron Micrograph ◽  
Picture Processing ◽  
Molecular Skeleton

Various authors have emphasized the spatial information resident in an electron micrograph taken with adequately coherent radiation. In view of the completion of at least one such instrument, this opportunity is taken to summarize the state of the art of processing such micrographs. We use the usual symbols for the aberration coefficients, and supplement these with £ and 6 for the transverse coherence length and the fractional energy spread respectively. He also assume a weak, biologically interesting sample, with principal interest lying in the molecular skeleton remaining after obvious hydrogen loss and other radiation damage has occurred.

A Macintosh Interface for the Cameca Camebax-Micro Electron Microprobe

1990 ◽  
Vol 48 (1) ◽  
pp. 438-439
Author(s):  
Carl E. Henderson
Keyword(s):  
Electron Microprobe ◽  
Processing Speed ◽  
Word Processing ◽  
State Of The Art ◽  
Computer Control ◽  
Third Party ◽  
Disk Storage ◽  
The Past ◽  
User Facility ◽  
Instrument Control

Over the past few years it has become apparent in our multi-user facility that the computer system and software supplied in 1985 with our CAMECA CAMEBAX-MICRO electron microprobe analyzer has the greatest potential for improvement and updating of any component of the instrument. While the standard CAMECA software running on a DEC PDP-11/23+ computer under the RSX-11M operating system can perform almost any task required of the instrument, the commands are not always intuitive and can be difficult to remember for the casual user (of which our laboratory has many). Given the widespread and growing use of other microcomputers (such as PC’s and Macintoshes) by users of the microprobe, the PDP has become the “oddball” and has also fallen behind the state-of-the-art in terms of processing speed and disk storage capabilities. Upgrade paths within products available from DEC are considered to be too expensive for the benefits received. After using a Macintosh for other tasks in the laboratory, such as instrument use and billing records, word processing, and graphics display, its unique and “friendly” user interface suggested an easier-to-use system for computer control of the electron microprobe automation. Specifically a Macintosh IIx was chosen for its capacity for third-party add-on cards used in instrument control.

Current Issues: Advanced Digital Technology for Supervising Graduate Clinicians

2010 ◽  
Vol 20 (1) ◽  
pp. 9-13 ◽  
Author(s):  
Glenn Tellis ◽  
Lori Cimino ◽  
Jennifer Alberti
Keyword(s):  
Real Time ◽  
Digital Technology ◽  
Clinical Training ◽  
State Of The Art ◽  
Clinical Skills ◽  
Slow Motion ◽  
Video Capture ◽  
Microsoft Excel ◽  
Clinical Supervisors ◽  
Training And Supervision

Abstract The purpose of this article is to provide clinical supervisors with information pertaining to state-of-the-art clinic observation technology. We use a novel video-capture technology, the Landro Play Analyzer, to supervise clinical sessions as well as to train students to improve their clinical skills. We can observe four clinical sessions simultaneously from a central observation center. In addition, speech samples can be analyzed in real-time; saved on a CD, DVD, or flash/jump drive; viewed in slow motion; paused; and analyzed with Microsoft Excel. Procedures for applying the technology for clinical training and supervision will be discussed.

Behavioral Genetics: Concepts for Research and Practice in Language Development and Disorders

1995 ◽  
Vol 38 (5) ◽  
pp. 1126-1142 ◽  
Author(s):  
Jeffrey W. Gilger
Keyword(s):  
Language Development ◽  
Behavioral Genetics ◽  
State Of The Art ◽  
Genetic Research ◽  
Great Promise ◽  
Behavioral Genetic ◽  
Fine Grained ◽  
Future Goals ◽  
Current State ◽  
Research Designs

This paper is an introduction to behavioral genetics for researchers and practioners in language development and disorders. The specific aims are to illustrate some essential concepts and to show how behavioral genetic research can be applied to the language sciences. Past genetic research on language-related traits has tended to focus on simple etiology (i.e., the heritability or familiality of language skills). The current state of the art, however, suggests that great promise lies in addressing more complex questions through behavioral genetic paradigms. In terms of future goals it is suggested that: (a) more behavioral genetic work of all types should be done—including replications and expansions of preliminary studies already in print; (b) work should focus on fine-grained, theory-based phenotypes with research designs that can address complex questions in language development; and (c) work in this area should utilize a variety of samples and methods (e.g., twin and family samples, heritability and segregation analyses, linkage and association tests, etc.).

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