Fabrication Flaw Density and Distribution in Piping Weldments

Doctor, Steven R

Title: Fabrication Flaw Density and Distribution in Piping Weldments

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Abstract

The U.S. Nuclear Regulatory Commission supported the Pacific Northwest National Laboratory (PNNL) to develop empirical data on the density and distribution of fabrication flaws in nuclear reactor components. These data are needed to support probabilistic fracture mechanics calculations and studies on component structural integrity. PNNL performed nondestructive examination inspections and destructive testing on archived piping welds to determine the fabrication flaw size and distribution characteristics of the flaws in nuclear power plant piping weldments. Eight different processes and product forms in piping weldments were studied including wrought stainless steel and dissimilar metal weldments. Parametric analysis using an exponential fit was performed on the data. Results were created as a function of the through-wall size of the fabrication flaws as well as the length distribution. The results are compared and contrasted with those developed for reactor pressure vessel processes and product forms. The most significant findings were that the density of fabrication flaws versus through-wall size was higher in piping weldments than that for the reactor pressure vessel weldments, and the density of fabrication flaws versus through-wall size in both reactor pressure vessel weld repairs and piping weldments were greater than the density in the original weldments. Curves showing these distributionsmore » are presented.« less

Authors:: Doctor, Steven R

Publication Date:: Tue Sep 01 00:00:00 EDT 2009

Research Org.:: Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

Sponsoring Org.:: USDOE

OSTI Identifier:: 1012896

Report Number(s):: PNNL-SA-66046
401001060; TRN: US1102384

DOE Contract Number:: AC05-76RL01830

Resource Type:: Conference

Resource Relation:: Conference: 20th International Conference on Structural Mechanics in Reactor Technology (SMiRT 20), August 9-14, 2009, Espoo, Finland, 257:393

Country of Publication:: United States

Language:: English

Subject:: 21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS; 36 MATERIALS SCIENCE; DEFECTS; DESTRUCTIVE TESTING; DISTRIBUTION; FABRICATION; FRACTURE MECHANICS; NUCLEAR POWER PLANTS; PARAMETRIC ANALYSIS; PRESSURE VESSELS; REACTOR TECHNOLOGY; REACTORS; STAINLESS STEELS; fabriation flaws; piping weldments; austenitic stainless steel; dissimilar metal welds

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                    Doctor, Steven R. Fabrication Flaw Density and Distribution in Piping Weldments.  United States: N. p., 2009. 
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                    Doctor, Steven R. Fabrication Flaw Density and Distribution in Piping Weldments.  United States.

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                    Doctor, Steven R. 2009.  
        "Fabrication Flaw Density and Distribution in Piping Weldments".  United States.

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@article{osti_1012896,

  title        = {Fabrication Flaw Density and Distribution in Piping Weldments},

  author       = {Doctor, Steven R},

  abstractNote = {The U.S. Nuclear Regulatory Commission supported the Pacific Northwest National Laboratory (PNNL) to develop empirical data on the density and distribution of fabrication flaws in nuclear reactor components. These data are needed to support probabilistic fracture mechanics calculations and studies on component structural integrity. PNNL performed nondestructive examination inspections and destructive testing on archived piping welds to determine the fabrication flaw size and distribution characteristics of the flaws in nuclear power plant piping weldments. Eight different processes and product forms in piping weldments were studied including wrought stainless steel and dissimilar metal weldments. Parametric analysis using an exponential fit was performed on the data. Results were created as a function of the through-wall size of the fabrication flaws as well as the length distribution. The results are compared and contrasted with those developed for reactor pressure vessel processes and product forms. The most significant findings were that the density of fabrication flaws versus through-wall size was higher in piping weldments than that for the reactor pressure vessel weldments, and the density of fabrication flaws versus through-wall size in both reactor pressure vessel weld repairs and piping weldments were greater than the density in the original weldments. Curves showing these distributions are presented.},

  doi          = {},

  url          = {https://www.osti.gov/biblio/1012896},
  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {Tue Sep 01 00:00:00 EDT 2009},

  month        = {Tue Sep 01 00:00:00 EDT 2009}

}

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