IR 05000259/1985021

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Insp Repts 50-259/85-21,50-260/85-21 & 50-296/85-21 on 850401-04.Violation Noted:Inadequate Design Calculations on Pipe Support HPCI R-86,R2
ML20127F513
Person / Time
Site: Browns Ferry  Tennessee Valley Authority icon.png
Issue date: 04/19/1985
From: Blake J, Liu W
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
To:
Shared Package
ML20127F482 List:
References
50-259-85-21, 50-260-85-21, 50-296-85-21, NUDOCS 8505200474
Download: ML20127F513 (6)


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Report Nos.: 50-259/85-21, 50-260/85-21, and 50-296/85-21 Licensee: Tenessee Valley Authority 500A Chestnut Street Chattanooga, TN 37401 Docket Nos.: 50-259, 50-260 and 50-296 License Nos.: DPR-33, DPR-52, and DPR-68 Facility Name: Browns Ferry 1, 2, and 3 Inspection Conducted: April 1-4, 1985 Inspector:-

W. C. Liu

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Date Signed Approved'by: #34 &

J. J. BlaW6; Section Chief

  1. ///Ir"1-Date Signed Engineering Branch Division of Reactor Safety SUMMARY Scope: This routine, unannounced inspection entailed 26 inspector-hours on site

.in the areas of seismic analysis for as-built safety-related piping systems (IE Bulletin 79-14), and pipe support baseplate designs using concrete expansion anchor bolts (IE Bulletin 79-02).

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Results: One violation was identified - Inadequate Design Calculations On Pipe

. Support HPCI R-86, R .

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8505200474 850426 PDR ADOCK 05000259 G PDR

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REPORT DETAILS Persons Contacted

' Licensee ~ Employees

' *G. Jones, Plant Manager

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  • R. Guthrie, Design Service / Nuclear Power
  • J. Marshall, Jr., Civil Design Project Engineer, DETS
  • D. Miss Engineering Group Supervisor
  • B. Morris,' Compliance
  • R. Lewis, Senior Shift Manager-J.~ Beason, Civil Engineer, Office of' Engineering R. Baird, Civil Engineer, Office of Engineering

.0ther . licensee employees contacted included engineers, security force members, and office personne NRC Resident Inspectors

  • G. Paulk, Senior Resident Inspector
  • C. Patterson, Resident Inspector
  • Attended exit interview Exit Interview The inspection scope and findings were summarized on April, 4,1985, with those persons indicated in paragraph above. The inspector ' described the -

areas inspected -and discussed in detail the inspection findings listed

.below. No dissenting comments were received from the license (0 pen) Violation 296/85-21-01, Inadequate Design Calculations on Pipe Support HPCI R-86, R2, paragraph '

(0 pen) Unresolved Item 259,260,296/85-21-02, Shear Force Distribution ~ for IEB 79-02 Design Calculations, paragraph (0 pen) Unresolved Item 259,260,296/85-21-03, Frequency / Deflection Criteria Used For Pipe Support Analysis, paragraph (0 pen) Inspector Followup Item 259/85-21-04, Design Calculation for Support No. CS R-11, paragraph The licensee did not identify as proprietary any of the materials provided to or reviewed by the inspector during this inspectio _

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2 .icensee Action on Previous Enforcement Matters This subject was not addressed in the inspectio . Unresolved Items Unresolved items are matters about which more information is required to determine whether they are acceptable or may involve violations or devia-tions. -Two new unresolved items identified during this inspection are discussed in paragraphs 5 and .- Seismic Analysis for As-Built Safety-Related Piping Systems (IE Bulletin 79-14). Program Status The inspector held discussions with licensee representatives with regard to the implementation of the IEB 79-14 and 79-02 program It was noted that the schedule for engineering design verification had been revised as follows:

Unit N Completion Date Scheduled Outage 1 March, 1987 6/87 - 3/88 2 September, 1986 11/86 - 6/87 3 December,1987 2/88 - 10/88 Discussions held with licensee representatives revealed that Browns Ferry pipe support group was responsible for implementation of both the IEB 79-14, pipe support design, and IEB 79-02, baseplate and anchor bolts analysis. Based on the current information, there are approxi-

, mately 5500 pipe supports involved in the program; piping stress analysis is about 50% complete; pipe support design is 40% complet However, no single piping system was finally issue Design Calculations

The inspector reviewed portions of the following design calculation packages in the areas of the IEB 79-14 and 79-02 programs

l Support N Piping System BFN Unit No.

l CS R-11, Rev. 3 Core spray 1

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CS R-21, Rev. 2 Core spray 1 L HPCI R-27, Rev. 1 High pressure coolant 2

! injection (HPCI)

RHR R-18. Rev. 1 Residual Heat Removal 2 l (RHR)

RHR R-90, Rev. 1 RHR 2

  • HPCI R-86, Rev. 2 HPCI 3

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  • Discrepancies identified during the revie The above design calculations with respect to-pipe support design and baseplate / anchor bolts analysis were ' reviewed for. conformance. to

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analysis criteria,' applicable code, NRC-requirements, and the licensee

< commitments. In addition, these calculations were evaluated during the s

review for: thoroughness, clarity, consistency,-- and ' accuracy. 'In

'7 general, the calculations appeared to be adequate in terms .of using

% . design input, assumptions, references, equations and tables, with the e exception of the following two supports:

(1) . Support No. HPCI R-86, Rev. 2, in the Unit 3 high pressure coolant

, injection system was examined. It was noted that portions of the desigri calculations had not been performed in accordance with licensee commitments ard the NRC requirement , - Sheet-2 of the calculation specified a 5/16-inch fillet weld to one-inch plate. The as-installed plate was li-inch thic The 5/16-inch weld which was subject to 12,000 pound load was simply evaluated by engineering judgement. No weld calculations were included in any part of the support calcula-tion to justify the weld size Sheet-3 specified a 3/4-inch plate for qualification, actual-

-.4 calculation was based on li-inch thick. Cross sectional area- -

of the plate showed A = 8 square inches, actual cross sec-

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tional area should be 12 square inche N

- - Sheet 5 showed two W6 x 15.5 structural members, one vertical

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- and one sloped, these two members had been removed, there were no notes to indicate that these members were either void-

, _ or supersed-ed. Furthermore,-weld calculation for the two attachment plates, li" x 8" x 8", as shown 'on the as-built

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. drawing could not be identified from the calculation packag .

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Sheet 6 specified plate size 11" x 12" x l'-2" with 3/4"

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i diameter bolt. There were no notes to indicate that the L plate had been revis~ed to li" x 15" x l'-3", and bolt size L had been changed to li" diameter. As-built drawing showed a E

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i-inch all around weld .for' the strut connection to the

horizontal steel bea But no weld calculations were per-formed.

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b 'N - Sheets 10 thru 13 showed Support No. R-90 and support detail assembl There were no notes to identify that the R-90 and

. the support assembly were void or superseded.

! TVA's Engineering procedure 3.03, Design Calculations, paragraph

[ g2 .3 states that all design calculations shall be checked for I

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adequacy by a qualified person. The checker must be able to provide independent review; paragraph 4.5 states that any configura-tion change given by an as-constructed drawing must be reconciled with 'the associated calculations. Calculations are often worked during . development to preserve history, with corner-to-corner-diagonal lines and _words such as " void", or " superseded". The

, preparers must ensure that each sheet is identifiable with the document, that the status of each sheet is clear, and that the document has continuity. Figure 11 of the procedure provides

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example revisions to calculation sheets that should be implemented

, by all design personnel.

The improper design analyses performed in the aforementioned support calculations are violations of 10 CFR 50, Appendix 8,

. Criterion III, and -is identified as Violation 296/85-21-01, Inadequate design calculations on pipe support HPCI R-86, R (2) Support No. CS R-11, Rev. 3,.in the Unit I core spray system was i reviewed. It was noted that the baseplate had two structural

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attachments. Each attachment had three forces and three moments.

g The baseplate had a thickness of 3/8-inch and was analyzed by hand

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calculations. Sheet 2 of the calculation was revised on March 9, 1983, but was not signed by the checke The inspector hel < discussions with the licensee representative with respect to the

baseplate analysis. It was determined that the baseplate will be reanalyzed by the computer applications to ensure that the plate stress and the anchor bolt loads are to be within the allowable Pending further review of the design calculation. This matter is

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identified as Inspector Followup Item 259/85-21-04, Design Calcula-tions for Support No. CS R-11.

  • ' Design Consideration Browns Ferry Design Criteria No. BFN-50-D707, Rev. 2, Analysis of

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as-built piping systems, was partially reviewed with respect to pipe

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support . design requirement It was noted that. the frequency / deflection criteria for the pipe support design were not addressed in the documen The inspector held discussions with 11cen-see representatives in the areas of piping stress analysis and pipe

support design. It was found that the pipe support group was not instructed to verify whether the supports were able to meet-the rigid requirements when the piping stress engineer modeled the supports as t_'

rigid in the stress analysi The designing of rigid pipe supports c without ' verifying frequency / deflection requirements had created incon-C sistencies between the pipe support designs and the piping stress

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, analyses, pending further evaluations with regard to the above

't.oncerns, this matter -is identified as Unresolved -Item 259, 260, 296/85-21-03, Frequency / deflection criteria used for pipe support

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analysi Within the areas inspected..one violation was identifie s

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6 .~ _ Pipe Support Baseplate Designs Using Concrete Expansion Anchor Bolts (IE Bulletin 79-02) Factor of Safety The inspector reviewed six pipe supports in the areas of the baseplate and anchor bolt calculations. It was noted that the factor of safety of anchor bolts used in the calculations met the IEB 79-02 require-ments.- Tension Shear Interaction Civil design standard DS-C1.7.1, Rev. 2, General Anchorage to concrete, was partially reviewed, paragraph 5.3 states that the shear capacity of the individual anchors is inversely proportional to the tensile load in the anchor. The inspector held discussions with licensee represen-tatives with regard to the above concern. It was found that Browns Ferry pipe support group had performed design calculations in accor-dance with the aforementioned instructions in that the shear force could be reduced to zero when the anchor bolt tensile load approached the allowable value. As a result, the verification of anchor bolt tension-shear interaction had become meaningless in terms of imprac-tical . shear force distribution to the anchor bolts, pending further evaluations with respect to the aforementioned concern, this matter is identified as Unresolved Item 259, 260, 296/85-21-02, shear force distribution for IEB 79-02 design calculation Within the areas inspected, no violations or deviations were identified.

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