ML20141K467

Trip Rept of 850923-26 Site Visit W/Teledyne Engineering Svcs Re Audit of S&W as-built Verification Walkdown

ML20141K467
Person / Time
Site:	Comanche Peak
Issue date:	10/11/1985
From:	Shao L NRC - COMANCHE PEAK PROJECT (TECHNICAL REVIEW TEAM)
To:	Noonan V NRC - COMANCHE PEAK PROJECT (TECHNICAL REVIEW TEAM)
References
NUDOCS 8601220536
Download: ML20141K467 (4)

Text

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6 p" "% - UNITED STATES -

y & NUCLEAR REGULATORY COMMisslON -

o WASHINGTON, D. C. 20555 g

oc$p$.os:/ 50-445/50-446 OCT 111985

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MEMORANDUM FOR: Vincent S. Noonan, Director, Comanche Peak Project FROM: Larry C. Shao, Manager, Engineering Group, Comanche Peak Project

SUBJECT:

TRIP REPORT

SUMMARY

- AUDIT OF CPSES AS-BUILT VERIFICATION BY SWEC On September 23-26, 1985, the staff and its consultants from Teledyne Engineering Services (TES) performed an audit of the Stone & Webster Engineering Corporation (SWEC) as-built verification walkdown at the Comanche Peak site. The SWEC walkdown was performed based on a random sample of large bore pipe supports and valves. The purpose of the staff audit was to verify the adequacy of SWEC walkdown. The staff audit included: 1) a review of the as-built walkdown procedures and results report, 2) a review and walkdown of a sample of the SWEC as-built walkdown packages, 3) a walkdown of two large bore piping stress isometric drawings, and 4) a review of the as-built reverification of snubber, strut, and valve orientations by TUGCO.

As-Built Walkdown Procedure and Results Report The staff reviewed a draft copy of Project Procedure CPPP-5, " Field Walk Procedure - Unit 1" (Revision 1), and a preliminary copy of the result report entitled, "Large Bore Field Walkdown Report." The purpose of the SWEC 'as-built walkdown was to verify that the as-built documentation is adequate to initiate the pipe stress analysis. The SWEC as-built walkdown was not intended to verify the adequacy of the as-built program. The Construction Assessment Program will assess the adequacy of the existing as-built documentation against the construction tolerances.

The SWEC walkdown verified the adequacy of four attributes obtained from a random selection of 680 large bore supports and valves. The four attributes were:

1) Valve location (sample size of 80),

2 Pipesupportlocation(samplesizeof200),

3 Pipe support function (sample size of 200), and 4 Valve and support orientation (sample size of 200).

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Of the four attributes evaluated, several. discrepancies were noted in" the valvet and support orientation attribute which exceeded the sampling' acceptance A criterion. As-a> result. TUGCO.had initiated corrective actions to reverify 100P of. snubber,'~ strut, and valve orientations for the large bore' piping systems tod be reanalyzed'by'SWEC.*The staff review of this corrective action is further discussed later in this memorandum.

g 860122 36 951011 "

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v V. Noonan OCT 111985 Staff Walkdown of As-Built Verification Packages The staff and consultants selected a sample of approximately 10 percent of the ShEC as-built walkdown packages for each of the four attributes. The staff review consisting of three 2-man teams independently verified each as-built package for the respective attribute checked by SWEC. Additionally, the staff checked the support or valve in each walkdown package for other attributes which can potentially affect the validity of the piping stress analysis. The staff walkdown of the SWEC as-built packages provided the staff with a clear understanding of how Project Proecedure CPPP-5 was implemented. The results and conclusions of the staff walkdown will be documented in a summary report currently in preparation.

Staff Walkdown of Piping Stress Isometrics The staff consultants selected two piping stress problems (which consisted of several piping isometric drawings) for an independent engineering walkdown. The staff walkdown was intended to provide an engineering assessment of the attributes associated with the IE Bulletin 79-14 as applicable to the two piping stress problems. The walkdown focused on those attributes which could impact the stress analysis results and should be considered in the piping analytical model. As-a-result of-the walkdown, the staff noted several-instances where the piping run geometry and clearances were not clearly identified in the piping isometric drawings. The staff requires additional information for resolution and this item will be discussed further with the applicant.

Reverification of Snubber, Strut, and Valve Orientation The applicant is currently in the process of performing a 100% reverification of snubber, strut, and valve orientations for large bore piping systems to be reanalyzed by SWEC. The staff review in this area consisted of two parts.

First, the staff reviewed the 200 support and valve drawings which were included in the SWEC sample population for this attribute in order to establish the homogeneity of the population. Second, the staff accompanied a TUGC0/ Brown

& Root as-built team who was performing the reverification walkdown.

Conclusions Contingent upon an acceptable resolution of the above identified item regarding piping run geometry and clearances, the staff concludes the following. Based on the staff review of the SWEC as-built walkdown results, the staff finds the ShEC walkdown to be well-documented and easily verifiable. The dimensions obtained in the staff's walkdown verified the accuracy of the SWEC dimensions as marked in the SWEC as-built walkdown packages. As a result, the staff concurs with the conclusions reached by SWEC regarding the acceptability of the four as-built attributes evaluated. The staff found no significant deviations with respect to valve location, support type, and support location. For support and valve orientation, the staff walkdown confinned ShEC's finding that several support and valve orientations exceeded their tolerance. The staff review of the reverification effort initiated by TUGC0 as a corrective action L _ _ . . - - - ____._________.___--_---a

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y Noonan -3.. OCT 111985 fjnds._the actions taken by TUGC0 adequately addresses the concern identified by the SWEC _walkdown.' .L W1th respect,to other. as-bullt attributes .(e.g., pipe

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run geometry, clearances, etc.), the SWEC walkdown must be supplemented by a TUGC0 or CPRT as-built walkdown.to assure the adequacy of the previous as-built program,' associated with IE Bulletin 79-14 '

., w L. C. Shao, Manager 1, Engineering Gre'ip Comanche Peak h*oject cc: D. Eisenhut, NRR C. Transrell, DL ,

R. Bosnak, DE '

'D. Norkin, IE S. Hou, TRT R. Masterson, TRT V. Ferrarini, TRT D. Landers, TES

! R.Hookway,TES(5)

D. Terao, TRT '

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'i V. Noonan -4 '

OCT 111985 -

. NRC Staff and Consultants D..Terao NRC/TRT R. D. Hookway .TES M. F. Moran TES J. J. Rivard TES W. J. Carey TES P. 'J. Hurley TES-Personnel -Interviewed J. Finneran TUGC0 J. Burgess. CPPE-

~-J. Oliver SWEC C. Watters SWEC.

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.________.________1________________.___.______.. . _ _ _ . _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ . _ _ _ _ _ . _ . _ _ _ _ _ _ _ _ . _ _ . _ _ _ _ _ _ _ _ . _ . . _ __ _._._.____1__ _ _ _ _ _ _ _ _ _ _ . _ _ _ _ ._______;