IR 05000528/1993024

Page 27 Inadvertently Omitted from NRC Inspection Repts 50-528/93-24,50-529/93-24 & 50-530/93-24

ML20056E720
Person / Time
Site:	Palo Verde
Issue date:	08/06/1993
From:	Miller L NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V)
To:
Shared Package
ML20056E520	List: IR 05000528/1993024 ML20056E518
References
50-528-93-24, 50-529-93-24, 50-530-93-24, NUDOCS 9308250105
Download: ML20056E720 (1)

Text

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- 27 corrosion ultrasonic test inspections and records, component

, evaluations (engineering evaluation reports), and corrective maintenance work orders. The NRC inspector found that the licensee had performed random quality assurance reviews of the erosion -

corrosion program in accordance with licensee in service inspection / inservice testing /special process module

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(ISI/IST/Special Process Module) Quality Monitoring Manua Personnel Interview and Review of Lamination Area Mao t

Interview The inspector interviewed the licensee erosion corrosion NDE UT thickness inspector who performed the examination which produced i different results than the NRC NDE mobile laboratory inspectors.

l The licensee's NDE inspector did not recall noting any abnormal t l

wall thickness readings or. piping flaws during the inspection of  ;

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interest. The NDE inspector also stated that he typically applied

! couplant, measured piping thickness by UT, and wiped off couplant  !

on three lines of an inspection grid at a time, i i

l The NDE inspector discussion of the UT pipe wall thickness l measuring procedure and process that he utilized, indicated that he i l

was both knowledgeable and capable of performing the UT pipe wall l l thickness measuring procedure. The NDE inspector appeared credible l l and convincing to the NRC inspector. In addition, reinspection of a  ;

sample of his previous inspections confirmed the adequacy of those inspections. The NRC inspector concluded that the licensee i inspector had performed the inspection in accordance with licensee  ;

procedures and within the skills of a level II nondestructive test i (NDT) inspecto l i

lamination Mao Review i 8 The inspector reviewed the laminar indication mapped by the  :

licensee. The inspector found that the lamination appeared in an t area that included thirteen 3"x 3" grid inspection squares. Each  !

of the grid inspection squares indicated a portion of the (

lamination. The lamination was not detected in 100% of any one of l the thirteen grid inspection squares. In one of the thirteen 3"x l 3" grid inspection squares, the lamination covered approximately 90% of the square. This square had the largest area of recorded lamination. The remaining grid inspection squares varied from one at approximately 60% recorded lamination to the remaining eleven at ,

approximately 5% to 40% recorded lamination within the grid l inspection square The inspector concluded that the licensee NDE UT inspector could have obtained the recorded thickness measurements in all of the grid inspection squares using licensee procedure, 73TI-0ZZO2, Revision 04.01, Ultrasonic Thickness Measurement. The grid that was 90% occupied by the lamination would have necessitated

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9308250105 930806 PDR ADOCK 05000528 O PDR

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