ML20132C715

Summarizes 850204 Discussions Re Appropriateness of NDT Methods for Structural Steel Fillet Weldments.Magnetic Particle Testing Only Appropriate Method Other than Visual Insp for Small Fillet Welds

ML20132C715
Person / Time
Site:	Wolf Creek, 05000000
Issue date:	02/14/1985
From:	Liaw B Office of Nuclear Reactor Regulation
To:	Novak T Office of Nuclear Reactor Regulation
Shared Package
ML20132C642	List: ML20132C638 ML20132C645 ML20132C691 ML20132C715 ML20132C719 ML20132C740 ML20132C755 ML20133B565 ML20133B641 ML20133B686 ML20133B738
References
FOIA-85-161 NUDOCS 8502250076
Download: ML20132C715 (2)

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• UNITED STATES c NUCLEAR REGULATORY COMMISSION j I WA5mNCTON, D. C. 20556 s FEB 141985 Docket No. 50-482 i

MEMORANDUM FOR: Thomas M. Novak, Assistant Director i for Licensing i Division of Licensing THRU:

William Materials,V. Johnston, Chemical Assistant Director

& Environmental Techno [lo Division of Engineering

]

FROM: B. D. Liaw, Chief g Materials Engineering Branch e Division of Engineering '

SUBJECT:

EVALUATION OF NONDESTRUCTIVE TESTING METHODS 9

~ APPROPRIATE TO STRUCTURAL STEEL WELDMENTS e (WOLF CREEK)  :

The purpose of this memorandum is to summarize discussions on February 4, 1985, concerning the appropriateness of various nondestructive testing methods for structural steel weldments. These discussions were the result of concerns for the adequacy of the visual inspections through coatings of some of the structural steel weldments at Wolf Creek Generating Station. There are four '

commercially accepted nondestructive testing methods; two surface inspection methods (liquid penetrant and magnetic particle) and two volumetric (radiography and ultrasonic). The method or methods used in a given situation depend on many factors. Structural steel weldments are usually fillet welds, a major factor for determining the appropriate inspection method.

For radiography, the short, discontinuous lengths of welds and welds being located back-to-back, access and source locations make placing of the film very difficult. With fillet welds, their triangular cross section gives a very wide range of density to the film image such that it is difficult to interpret or assign meaning to an indication. For this reason, standards have not been developed for the radiography of fillet welds. Accordingly, radiography of structural steel weldmer)ts (fillet welds) is not performed.

Ultrasonic testing has very similar limitations, and it is also not appro-priate for fillet welds. .

Making a choice of surface inspection method between liquid penetrant and magnetic particle involves several other considerations. That many of the welds at the Wolf Creek site have been coated makes the liquid penetrant method ineffective. The paint covers or fills the cracks and other type voids / defects such that the liquid penetrant method would not detect them.

Contact:

D. Smith

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Thomas M. Novak FEB 141985 However, the paint does not affect t'he magnetic characteristics of the steel and defects detectible by magnetic particle would probably be detected. It is the only nondestructive method of inspection other than visual which would be effective for inspection of the rather small fillet welds normally seen in structural steel welding.

It must be cautioned that qualified procedures, equipment, personnel, etc.

and agreed-upon standards of what are significant indications must be used for the inspections to be meaningful.

Ori;inzi signed by <

B. D. Liaw B. D. Liaw, Chief Materials Engineering Branch

. Division of Engineering

- cc: J. P. Knight W. Johnston E. Sullivan S. Pawlicki W. Hazelton C. Y. Cheng

. Klecker IEEEilh37, DISTRIBUTION:

DMB - Docket Files MTEB Reading Files MTEB Wolf Creek Files SEE PREVIOUS CONCURRENCES SHEET

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<9f; s . n al l OFC : DE:MTEB  : DE:MTEB  : DE  :

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NAME :D. Smith: jar :W.Hazelton : B.D. iaw :W.V. Johnston  :  : :

DATE : 2/11/85  : 2/ /85 : 2/ () /85 :2/ 1 5 /85 :  :  :

0FFICIAL RECORD COPY