Selected CANDU Pressure Tube Degradation Mechanisms and Inspection Related Issues
Ontario Power Generation; Inspection & Maintenance Services Division (IMS) has been operating a variety of inspection systems to perform volumetric and surface non-destructive examinations of the CANDU reactor pressure tubes using ultrasonics. Experience acquired over more than 20 years allows for relatively reliable detection, sizing and characterization of various flaws and artifacts present in pressure tubes. The purpose of this paper is to discuss inspection related issues (detection, sizing and characterization) related to selected pressure tube degradation mechanisms. The discussion will include degradation phenomena common to all CANDU PHWR plants (multi and single unit stations, AECL and Ontario Hydro designs) and phenomena specific to a certain plant configuration or power unit. There are several ways to categorize pressure tube flaws. The categorization can be based on source of flaw (manufacturing, installation or in-service), flaw location (ID, OD or material) and flaw severity. There is also a variety of flaws within the broadly defined categories. The proper categorization and characterization of detected flaws is extremely important for the engineering assessment as some categories of flaws can be assessed as blunt whereas others have to be assessed as sharp. This may have a serious impact on reactors operating restrictions. Thanks to the large number of tubes inspected over the years, OPG-IMS has collected an extensive library of information with respect to the pressure tube flaws. Many of the flaws have been also replicated providing additional information which complements or validates NDE data. This data is now available for both qualitative and quantitative assessments and comparisons.
CANDU pressure tubes flaws inspection ultrasonics.
Michael TRELINSKI
Inspection & Maintenance Services Ontario Power Generation 230 Westney Rd. South Ajax, Ontario L1S7R3 Canada
国际会议
第十七届世界无损检测会议(17th World Conference on Nondestructive Testing)
上海
英文
957-964
2008-10-25（万方平台首次上网日期，不代表论文的发表时间）