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Title: Acceptance criteria for reactor coolant pumps and valves

Abstract

Each of the six primary coolant loop systems of the Savannah River Site (SRS) production reactors contains one reactor coolant pump, one PUMP suction side motor operated valve, and other smaller valves. The pumps me double suction, double volute, and radially split type pumps. The valves are different size shutoff and control valves rated from ANSI B16.5 construction class 150 to class 300. The reactor coolant system components, also known as the process water system (PWS), are classified as nuclear Safety Class I components. These components were constructed in the 1950`s in accordance with the then prevailing industry practices. No uniform construction codes were used for design and analysis of these components. However, no pressure boundary failures or bolting failures have ever been recorded throughout their operating history. Over the years, the in-service inspection (ISI) was limited to visual inspection of the pressure boundaries, and surface and volumetric examination of the pressure retaining bolts. Efforts are now underway to implement ISI requirements similar to the ASME Section XI requirements for pumps and valves. This report discusses the new ISI requirements which also call for volumetric examination of the pump casing and valve body welds.

Authors:
; ;
Publication Date:
Research Org.:
Westinghouse Savannah River Co., Aiken, SC (United States)
Sponsoring Org.:
USDOE, Washington, DC (United States)
OSTI Identifier:
10159788
Report Number(s):
WSRC-MS-93-182; CONF-930702-19
ON: DE93012758; TRN: 93:015207
DOE Contract Number:
AC09-89SR18035
Resource Type:
Conference
Resource Relation:
Conference: 1993 American Society of Mechanical Engineers (ASME) pressure vessel and piping conference,Denver, CO (United States),25-29 Jul 1993; Other Information: PBD: [1993]
Country of Publication:
United States
Language:
English
Subject:
22 GENERAL STUDIES OF NUCLEAR REACTORS; PRODUCTION REACTORS; PUMPS; VALVES; SPECIFICATIONS; SAVANNAH RIVER PLANT; FAILURES; INSPECTION; WELDED JOINTS; REACTOR COOLING SYSTEMS; FASTENERS; FRACTURE MECHANICS; CRACKS; 220600; 220200; RESEARCH, TEST, TRAINING, PRODUCTION, IRRADIATION, MATERIALS TESTING REACTORS; COMPONENTS AND ACCESSORIES

Citation Formats

Gupta, N.K., Miller, R.F., and Sindelar, R.L. Acceptance criteria for reactor coolant pumps and valves. United States: N. p., 1993. Web.
Gupta, N.K., Miller, R.F., & Sindelar, R.L. Acceptance criteria for reactor coolant pumps and valves. United States.
Gupta, N.K., Miller, R.F., and Sindelar, R.L. Sat . "Acceptance criteria for reactor coolant pumps and valves". United States. doi:. https://www.osti.gov/servlets/purl/10159788.
@article{osti_10159788,
title = {Acceptance criteria for reactor coolant pumps and valves},
author = {Gupta, N.K. and Miller, R.F. and Sindelar, R.L.},
abstractNote = {Each of the six primary coolant loop systems of the Savannah River Site (SRS) production reactors contains one reactor coolant pump, one PUMP suction side motor operated valve, and other smaller valves. The pumps me double suction, double volute, and radially split type pumps. The valves are different size shutoff and control valves rated from ANSI B16.5 construction class 150 to class 300. The reactor coolant system components, also known as the process water system (PWS), are classified as nuclear Safety Class I components. These components were constructed in the 1950`s in accordance with the then prevailing industry practices. No uniform construction codes were used for design and analysis of these components. However, no pressure boundary failures or bolting failures have ever been recorded throughout their operating history. Over the years, the in-service inspection (ISI) was limited to visual inspection of the pressure boundaries, and surface and volumetric examination of the pressure retaining bolts. Efforts are now underway to implement ISI requirements similar to the ASME Section XI requirements for pumps and valves. This report discusses the new ISI requirements which also call for volumetric examination of the pump casing and valve body welds.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Sat May 01 00:00:00 EDT 1993},
month = {Sat May 01 00:00:00 EDT 1993}
}

Conference:
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  • The results of Stage 2 of the Regulatory Instrument Review are presented in this volume. Selected regulatory instruments, such as the Code of Federal Regulations (CFR), US Nuclear Regulatory Commission (NRC), Regulatory Guides, and ASME Codes, were investigated to determine the extent to which these regulations apply aging management to selected safety-related components in nuclear power plants. The Regulatory Instrument Review was funded by the NRC under the Nuclear Plant Aging Research (NPAR) program. Stage 2 of the review focused on four safety-related structures and components; namely, cables, containment and basemat, reactor coolant pumps, and motor-operated valves. The review suggestsmore » that the primary-emphasis of the regulatory instruments was on the design, construction, start-up, and operation of a nuclear power plant, and that aging issues were primarily addressed after an aging-related problem was recognized. This Stage 2 review confirms the results of the prior review; (see Regulatory Instrument Review: Management of Aging of LWR Major Safety-Related Components NUREG/CR-5490. The observations indicate that the regulations generally address management of age-related degradation indirectly. Specific age-related degradation phenomena frequently are dealt with in bulletins and notices or through generic issues, letters, etc. The major recommendation of this report, therefore, is that the regulatory instruments should more directly and explicitly address the aging phenomenon and the management of the age-related degradation process.« less
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