ML20211F733

Forwards Rev 0 of Piping & Structural Design Review Criteria for Millstone Unit 2 Icavp

ML20211F733
Person / Time
Site:	Millstone
Issue date:	08/11/1997
From:	Curry D, Rothen F AFFILIATION NOT ASSIGNED, NORTHEAST NUCLEAR ENERGY CO.
To:	Lieberman J NRC OFFICE OF ENFORCEMENT (OE), NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20211F681	List: B16690, Responds & Updates Reply to NRC Re Violations Noted in Insp Repts Conducted Between 970728-0801.Corrective Actions:Significantly Reduced Number of Vehicles in Protected Area & Mgt Support of Security Visible ML20211F674 ML20211F733
References
EA-97-104, NUDOCS 9710010197
Download: ML20211F733 (3)

Text

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'PARCONO Daniel L. Curry, vu e hewent twts W n Part.ont FWer Group int P075 Atwgantown Road

• fkad ag I'enntvivan>a 1W.07 e (610) f;% 23(.C.

• Iin W10) 65Pw2 September 29,1997 Dockc#, No. 50 336 Parsons NUht2 PPNR-0610 L U.S. Nuclear Re ' %rv Commission Attention: Dm" ment Co; 11 Desk Washington, 1.0,2055!

hiillstone Nuclear Power Station Unit No. 2 Indepsndent Corrective Action Verification Program flCAVP)

Gentlemen:

This letter transmits Revision 0 of the " Piping and Structural Design Review Criteria for hiillstone Unit 2 ICAVP". These criteria were developed for performing Tier i piping system reviews of the pipe stress analysis, pipe support calculations, and structural calculations for cable tray, conduit and duct. U. S.

Nuclear Regulatory Commission review and approval of the sampling approach noted in this submittal is

requested.

Contact me at (610) 855-2366 if you require additional information.

Sincerely, cktlb b A*'i Daniel L. Cu:Ty Parsons ICAVP Project Direc r DLC:djv

Attachment:

Piping and Structural Design Review Criteria for hiillstone Unit 2 ICAVP Revision 0 cc: E. Imbro (2) USNRC

11. Eichenholz - USNRC R. Laud;nat - NNECo J. Fougere - NNECo Rep. Terry Concannon - NEAC 9710010197 970929 PDR ADOCK 05000336 P PDR

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PIPING AND STRUCTURAL DESIGN REVIEW CRITERIA - l MILLSTONE UNIT 2 ICAVP )

The following guidelines are developed for performing the pipe stress, pipe support, and stmetural calculation for cable tray, conduit and duct supports reviews associated with the Tier 1 ICAVP for Millstone Unit 2. This design rniew process is similar to a design verification, with the exception that it will not be performed on a line-by-line basis. In addition to the rniew of calculations, a design review of respectis e design basis documents will be performed against the applicable licensing basis.

These guidelines will be implemented for all systems selected for the Millstone Unit 2 Tier 1 ICAVP.

1.0 PITE STRESS CALCULATIONS 1.1 Large Bore (>2") Piping Stress Calculations A two level process will be implemented for the design review of large bore piping systems. The first level rniew will be performed for the whole population to ensure that the design parameters, as documented by the calculations, are consistent with the applicable licensing and design basis criteria. The second level rniew will include 20% of all large bore pipe stress calculations. Of the 20% selected, half will be a random sample and the other half will be a smart sample.

The 10% smart sampk will be selected based en engineering judgment with consideration for: (1) identification of the organization responsible for the calculation, (2) identification of common attributes bctaca (14 alculatiom which will allow grouping, 0) identincation of most critical calculationr, (4) sections containing motor operated or air actuated valves w hich are srpported by the pipe, and (5) consideration of system multiple train design. The second level review will verify the repetitive tasks of the computer analysis portion of each calculation. Repetitive tasks are defined as modefng of the piping syrtem, preparing the piping computer code input, performing the analysis and obtaining computer output, plus verification of the computed stress values against Code allowable stresses. This review will verify that the design information is correctly and accurately entered into the piping analysis computer code and that the computer output results support the conclusions of the calculation.

This two-level resiew procca4 will provide assurance that the large bore piping analysis qualifications will be subjected to a thorough design review, 1.2 Small Bore (2" and under) Piping Stress Calculations A 20% random sample design rniew of small bore piping stress calculations containing computer analyses will be performed. A 20% random sample design review will be performed for field routed and sug arted small bore piping systems. A minimum of 3 small bore piping stress calculations and 3 field routed piping

, systems will be rniewed.

1.3 -

Tubing Stress Calculations A 10% random sample design review of the total number of tubing stress calculations and/or design documentation will be performed. The sample will include one of each group of redundant transmitters that are used to initiate system operation.

1.4 Vent and Drain Stress Calculations A 10% random sample design review of the total number of vent and drain stress calculations and/or design documentation will be performed. The sample will include one of each interface type that is applicable to the system.

Revision 0 September 29,1997 page1of2

o 2.0 P!PE SUPPORTS in general, pipe supports fall into three categories, (1) component supports, (2) supports built of structural steel, and (3) standard supports. Component supports consist of pipe clamps with a spring, snubber, strut or other star.dar? components from vendor catalogs with a structural steel or baseplate-to concrete attachment.

Structural & I supports are bmit-up box frames consisting of W-shapes or structural angle with U-bolts or straps. Component supports may be attached to structural steel framing Standard pipe supports are generally provided in a design criterion with maximum loadings provided for small bore pipe and tubing.

2.1 Component Pipe Supports The qualifying calculations typically address the evaluation of standard components, welds to steel attaclunents and baseplates, local structural steel evaluations or anchor bolts to concrete, and other common characteristics. All pipe supports will be group ~l by support type, such as variable springs, snubbers, struts, etc. Within each group, supports will ILt.n be categorized by parameters such as critical loading, thermal movements, stress, and geometric configuration. Each group will then be screened and 20% of the total number of supports within each group will be selected for design resiew. Of the 20% selected, half of the pipe support calculations will be based on a random selection and half will be a representative selection. The representative sample will be based on the most critical support parameters and engineeringjudgment. Some supports at pipe rupture locations will be included in the selected sample. This selection process is deemed sufficient due to the repetitive nature of the pipe support calculations. A rtinimum of 3 pipe supports from each grouping will be reviewed.

2.2 Structural Stect Pipe Supports These calculations consist of the evaluation of the structural steel members, welds, local structural attachments, and/or anchor bolts to concrete. All supports will be grouped, categorized, and a 20% population cele.:d for design review as outlined in paragraph 2.1. A minimum of 3 pipe supports from each grouping will be rniewed.

l 2.3 Standard Pipe Supports Each standard or typical pipe support configuration may be used multiple times within a piping subsystem.

Supports configurations within the selected systems will be grouped, categorized, and a 20% population selected for design resiew as outlined in paragraph 2.1. A minimum of 3 pipe supports from each grouping will be reviewed.

3.0 TUBING SUPPORTS Each standard and non-standard tube support configuration may be used snultiple times within a tubing system. Tubing supports configurations within the selected system boundaries will be grouped, categorized, and a 20% population chosen for design resiew as outlined in paragraph 2.1. A minimum of 3 pipe supports from each grouping willbe reviewed.

4.0 CONDUIT, CABLE TRAY AND DUCTWORK SUPPORTS Conduit, cable tray and ductwork supports designs were generated as standard and non-standard configurations. Configurations within the selected systems will be grouped, categorized, and a 20%

population choren for design review as outlined in paragraph 2.1. A minimum of 3 conduit. cable tray, and ductwork supports from each grouping will be resiewed.

Revision 0 september 29,1997 page 2 of 2

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