ML20237L365

Unit 2,Regeneration of Support Design Calculations on Rigorously Analyzed Piping,Program Plan

ML20237L365
Person / Time
Site:	Sequoyah
Issue date:	08/21/1987
From:	TENNESSEE VALLEY AUTHORITY
To:
Shared Package
ML20237L142	List: ML20237L140 ML20237L365
References
PROC-870821, TAC-R00201, TAC-R00202, TAC-R201, TAC-R202, NUDOCS 8708280072
Download: ML20237L365 (7)

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ENCLO2URE 1 SEQ'JOYAH NUCLEAR PLANT - UNIT 2 REGENERATION OF SUPPORT DESIGN CALCULATIONS ON RIGOROUSLY ANALYZED PIPING PROGRAM PLAN TABLE OF CONTENTS

1.0 INTRODUCTION

2.0 OBJECTIVES

3.0 BACKGROUND

4.0 PROGFAM LOGIC 5.0 . REVIEW AND REGENERATION OF CALCULATI e3 6.0 PRIORITI8S 7.0 PIPI: EUPPOET DESIGN CRITERIA P0 ACCEPTANCE CRITERIA l

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SEQUOYAH NUCLEAR PLANT - UNIT 2 AND COMMON REGENERATION OF SUPPORT DESIGN CALCULATIONS ON RIGOROUS ANALYSIS PIPING

1.0 INTRODUCTION

This plan provides a description of the program for review and regeneration of pipe support calculations associated with rigorously analyzed category 1 piping systems (referred to as " supports").

2.0 OBJECTIVES The overall program for the review and regeneration of pipe support calculation associated with rigorously analyzed piping includes two major objectives:

a. Determination of ovecall compliance of existing pipe support calculations to licensing commitments.

b. Reg 6neration of all pipe support calculations that are not retrievable or are inadequate as determi-wd in activity A.

3.0 BACKGROUND

The TVA calculation validation program indicates that approximately 6,000 category 1 pipe support calculations will require evaluation / regeneration. The majority of the pipe support calculations generated during the plant construction phase were performed by two vendors: EDS/Impell designing pipe supports inside containment, and f Basic Engineering designing supports outside containment. The balance of the Sequoyah Nuclear Plant (SQN) supports were designed by TVA.

Subsequent to receipt of an operating license, design modifications affecting supports have been performed by TVA.

4.0 PROGRAM LOGIC The plan to establish the pipe support design adequacy involves the following logic:

• quantify and document total scope

• prioritize overall scope for regeneration

• collect pipe support design input

• verify the pipe support as-installed function

• evaluate existing support calculations

• regenerate noneetrievable calculations Figure 1 indicates the program logic.

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-g-5.0 REVIEW AND REGENERATION OF CALCULATIONS l 5.1 Definition of Scope and Collection of Input Information i 5.1.1 Identification of Pipe Support Calculations on Rigorously Analyzed Category 1 Piping Based on a definition of category 1 system boundarios and an index of all rigorously analyzed piping, stress calculations for category 1 systems will be determined. A set of stress analysis problem connectivity diagrams will be developed to list and show connectivity of rigorous stress analysis problems. The support locations will be identified from the mathematical models (stress problem isometric sketches), and all pipe supports on rigorously analyzed category 1 piping will be identified. Additionally, pertinent documentation for each support and analysis problem will be identified and retrieved through the use of the TVA database " Calculation Cross Reference Index System" (CCRIS) and " Records Information Management System" (RIMS).

5.1.2 Functional Verification A field review will be performed for functional verification of all pipe supports by a walkdown of the supports for critical attributes (e.g., directionality, type, location, and etc.). Additionally, the field verification will identify all other attachments on category 1 hangers. The field verification data will be utilized in review and regeneration activities.

5.1.3 Collection of pipe Support Design Input A review will be performed to establish and collect piping loads and movements and other applicable design input for use in the pipe support calculation review and regeneration effort.

5.2 Screening of Pipe Support Calculations At our meeting on June 19, 1987, TVA proposed a screening criteria for prioritizing support evaluations. The purpose of this screening was to segregate the supports that may require modification so that the corresponding calculations could be reviewed / regenerated and resulting modifications identified and installed on a priority basis.

Based on subsequent implementing experience, TVA has determined that the above-described screening was not resource effective. Efforts spent segregating calculations could be better utilized performing necessary support evaluations, thereby ensuring timely resolution of this critical issue.

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1 Accordingly, SQN pipe support calculations will not be evaluated with the recommended priority system based on screening attributes. )

Rather, all evaluations for inside containment supports and outside '

containment cupports will be completed and modifications identified before mode 4. Program documentation and report generation will be finalized by October 19, 1987.

The evaluation and regeneration of the pipe supports will utilize the pipe support design criteria described in section 8.0.

5.3 Pipe Support Calculation Evaluation / Regeneration 5.3.1 Review of Existing Calculations RIMS and business records of contractors involved in the uriginal design will be accessed for all pipe support calculations. All retrieved calculations will be assessed for technical and documentation adequacy and will be reviewed for applicable loading and specific configuration attributes, including data obtained through field verification activity.

5.3.2 Regeneration of Pipe Support Calculations That Are Not l Retrievable or Are Inadequate Support calculations that are inadequate or cannot be retrieved will be regenerated using calculation of record loads, applicable licensing commitments, and design criteria.

5.4 Resolution of Discrepancies Any modifications to pipe support designs identified as a result of this plan will be documented and evaluated in accordance with TVA Quality and Engineering Assurance Procedures. I 6.0 PRIORITIES The priorities for the various tasks and activities involved in this program are arranged in such a manner as to support SQN unit 2 restart.

All support calculations which require modifications inside unit 2 steel containment vessel will be identified and completed as a first step.

This will be followed by evaluation of all support calculations outside unit 2 containment.

7.0 PIPE SUPPORT DESICN CRITERIA The pipe support design criteria established for this review and regeneration effort are consistent with TVA's interpretation of the Final Safety Analysis Repore (FSAR), with the following addition.

Manufacturers' Standardization Society Standard Practice (SP)-S8 design criteria will be used for all standard component supports for which appropriate component load rating data are available. For those

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_4-components that SP-58 data are not'available, e.g., snubbers, struts, ar.d clamps procured to American Society of Mechanical Engineers (ASME). ,

subsection NF code requirements, the methodology and load rating data of NF will be utilized.

The governing code for piping evaluation, in accordance with section 3,9.2 of the FSAR, is ANSI B31.1-1967 Code. Accordingly, structural shapes (supplementary steel in accordance with ANSI B31.1) will comply with the rules 'specified in the American Institute of- Steel Construction

" Manual of Steel Construction," 8th edition (1980), for'" Normal" and

" Upset" loading conditions. Section 3.8 of the FSAR, which limits stresses in steel structures under Safe Shutdown Earthquake loading, will i be utilized for the faulted loading condition.

-Detailed definitions of the requirements used in the pipe support calculation regeneration / evaluation program are given in detail in TVA procedure SQN-DC-V-24.2.

8.0 ACCEPTANCE CRITERIA Supports that do not meet the criteria in section 7.0 will be evaluated in accordance with TVA's Nuclear Engineering Proceudre (NEP)-9.1 (Corrective Action) to determine the corrective action to be taken and

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whether this action is required before restart. The engineering design modification and supporting calculation will be completed'before the restart /postrostart determination and used as input to the NEP-9.1 process.

The restart criteria contained in Volume 2 of the Nuclear Performance Plan will be utilized as the basis of the pre- or postrestart determination.

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ENCLOSURE 2 T/A COMMITMENTS PROGRAM DESCRIPTION FOR UNIT 2 REGENERATION OF PIPE SUPPORI' CALCULATIONS ON RIGOROUS AllALYSIS PIPING

1. Unit 2 - Evaluate pipe support calculations and generate support modification packages for inside and outside containment systems before mode 4.

2. Unit 2 - Complete program documentation and report for pipe support regeneration effort by October 19, 1987.

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AUG 11 '87 13:04 (615) 632-4519

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1. : ' ' ~ FIGURE 1 Sequoyah Nuclear Plant . Unk 2 & Common, PIPE SUPPORT CALCULATION REGENERATION

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LOGIC DIAGRAM TOTAL SCCPE I

1f FUNCTIONAL VERIFICATION

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. i DATA COLLECTION 1

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SUPPORTS WITH SUPPORTS WITH EXISTING CALCULATIONS '

$8 SING CALCULATIONS '

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YES CALCULATIONS , f COMPLETE &

CLOSURE ACCEPTABLE 7 <

J N_O g REGENERATION OF CALCULATIONS

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%- ACCEPTABLE 7 CLOSURE ,

1 NO q r I MODIFICATION ENGINEERED CAOR

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