ML18040A162

Rev 2 to 25A5583, Shroud Repair Hardware.

ML18040A162
Person / Time
Site:	Nine Mile Point
Issue date:	01/16/1995
From:	Trovato J GENERAL ELECTRIC CO.
To:
Shared Package
ML17059A889	List: ML17059A888 ML18040A162 ML18040A237
References
25A5583, 25A5583-R02, 25A5583-R2, NUDOCS 9508080031
Download: ML18040A162 (14)

Text

25A5585 SH WO.

GENm&iar&wrgy REV.2 1

EIS IDENT: SHROUD REPAIR REVISION STATUS SHEET DOCUMENT TITLE SHROUD REPAIR HARD'WARE TYPE: DBSIGN SPECIFICATION FMF: NINE MILEPOlNT 1 MPLNO: PRODUCT

SUMMARY

SECTION 7 DENOTES CHANGE THIS ITEM IS OR CONTAINS A SAFETY-RELATED ITEM YES REVISION Q NO + EQUIP CLASS CODE P RM-01607 11/11/94 J. L. TROVATO 12/19/94 RJA RM-01832 CHK BY: J. L. TROVATO 2 J;L. TROVATO J~~ f g )g95 RJA CONTROL ISSUE CN-02080 CHK BY: J. L. TROVATO PRINTS TO MADE BY APPROVALS GENBRAI. ELECTRIC COMPANY 175 CURTNER AVENUE J. L. TROVATO 10-24-94 W. F. FARRELL 11-09-94 SAN.IOSB CALIFORNIA95125 CHKD BY: ISSUED J. L. TROVATO 11-09-94 R.J. AHMANN11-11-94 CONT ON SHEET 2 MS-WORD (Ol/16/95 2:28 PM) 950S08003i 950i23

,PDR ADOCK

' 05000220

'.P", .PAR

25A5588 se No. 2 GENacfaar &wrgy REV. 2

1. SCOPE 1.1 This document defines the design and performance requirements for stabilizers and H8 support brackets for the core shroud which will functionally rcplacc wclds Hl through H8. A sketch of the welds and their nomenclature is given in Figure 1 ASME Code requirements

~

arc given in thc document of Paragraph 2.1.l.b.

2. APPLICABLE DOCUMENTS 2.1 . Thc following documents form a part of the specification to the extent specified herein.

2.1.1

a. Liquid Penetrant Examination ESOYP22

b. Shroud Repair, Code Design Specification 25A5586

c. Fabrication of Shroud Stabilizer 25A5584

d. Nine Mile Point 1 Shroud Data 105E1418A 2.1.2 c. Documents under thc following identities are to bc used with this specification:

a. Reactor Components 888HA7I5

b. Essential Components 22A8041 2.2 . Thc following documents form a part of this specification to thc cxtcnt specified herein.

2.2.1

a. Section III,Appendices, 1989 Fdition.

b. Section III, Subsection NB, 1986 Edition

c. Section III, Subsection NG, 1988 Edition with Addenda through Summer 1984.

d.Section IX, Welding and Brazing Qualifications, 1989 Edition

25A558S sH No. S REV. 2 2,5 QFSAR, Nine Mile Point 1, Rcv. 12

b. NMPC, Licensing Basis Seismic Analysis Data for the Reactor Building, NMPl (Soil Stiffness Data), Faxed on 8/27/94

c. NMPC, Licensing Basis Reactor Building Analysis data extracts, Faxed on 8/27/94 and 9/6/94

d. NMPC, Licensing Basis Reactor Support Structure Dynamic Analysis Data Extracts, Faxed on 9/9/94 c Design Criteria Document, "Criteria for Seismic Analysis", ¹ DCD-115, Rev, 0 S. GENERAL DESCRlPTION 3,1 Thc purpose of thc shroud stabilizers and H8 weld support brackets is to structurally replace welds Hl through H8, as defined in thc document of paragraph 2.l.ld, Wclds Hl through H6B are all of thc circumferential wclds in the shroud. Weld H7 is thc shroud.to shroud support ring weld. Weld H8 is thc bimetallic weld of thc shroud support ring to thc shroud support conc. These wclds werc required to both vertically and horizontally support the core top guide, core support plate, and shroud head; and to prevent core flow bypass into thc downcomer region. The core top guide and core support plate horizontally support thc fuel assemblies and maintain thc correct fuel channel spacing. thereby assuring control rod I

insertion.

4. REQUIREMENTS 4.]

4.1.1 The Shroud Stabilizer and H8 Support Brackets are not classified as ASME Code components. Howcvcr, material properties for the design analysis of these items shall bc obtained from the document in Paragraph 2.2.l,a, and welding qualification shall be performed in accordance with the document in Paragraph 2.2.l.d. Thc nomenclature for stress intensity used in this document is thc sarnc as that used in the documents of Paragraph 2.2.l.b and 2.2.l.c. The Shroud Stabilizers and H8 Support Brackets shall mcct or. exceed thc original construction requirements for the shroud.

4.2 4.2.1 Ail structural analysis shall be performed in accordance with thc criteria given in the document in Paragraph 2.S.a and the additional requirements of this specification. All of the load combinations given in Paragraph 4.5.5 shall bc shown to satisfy the primary and

25A5588 sH No. 4 RF.V. 2 secondary stress limits given in Section XVl, A,2.7 of the document listed in Paragraph 2.8.a with values of SFmin as dcflned in Paragraph 4.3,6. The appropriate SFmin values have been incorporated into the allowable stress intensity values given in Paragraphs 4.2.1.1 and 4.2.1.2.

4.2.1.1 Thc primary stresses {Pm, Pl, and Pl+ Pb) in the existing shroud, during normal and upset events, shall be shown to be less than Sm, 1.5Sm, and 1.5Sm rcspcctivcly. During emergency events, the allowable stresses are increased by a factor of 1.5 times the values for normal and upset events. During faulted events, the allowable stresses are increased by a factor of 2.0 times the values for normal and upset events, 4.2.1.2 The stresses (Pm, Pm+ Pb, and Pm+ Pb+ Q) in the repair hardware, during normal and upset events, shall be shown to bc less than Sm, 1.5Sm, and 3.0Sm respectively. During emergency events, the allowable primary stresses are increased by a factor of 1.5 times thc values for normal and upset events. During faulted events, thc allowable primary strcsscs arc incrcascd by a factor of 2.0 times the values for normal and upset events. Secondary stresses are notlirnited during emergency and faulted events.

4.2,2 The values of Sm and Sy for fnconcl alloy X-750 at operating temperature (defined in paragraph 4.3.8.1) are 47,500'psi and 92,800 psi, rcspcctivcly. The Sm values for the Inconel SB168 shroud cone and thc 304 stainless steel shroud arc 23,300 psi and 15,800'psi, rcspcctivcly. For all other applications, the values of Sm and Sy as well as any other required ntaterial property shall bc obtained from thc document in Paragraph 2.2,1.a. If Certifie Material Test Reports (CMTRs) are available, the value of Sm may bc dctcrmincd using the tncthod in Appendix Ill of the document in Paragraph 2,2.l,a, 4.2.3 The maximum permanent deflectio of any point on thc shroud adjacent to either thc li2 or the H3 weld shall bc less than 2.l inches divided by SFmin, during all of the load combinations specified in Paragraph 4,3.5, The maximum permanent dcflcction of any point on the shroud adjacent to either the HGA or HGB weld shall bc less than 0.75 inch divided by SFn~in, during all of the load co>nbinations spcciflcd in Paragraph 4.8.5. The maximum transient clastic dcflcction during the seismic event adjacent to cithcr the H6A or H6B weld shall bc less than 1.68 inch diridcd by SFmin spccifled in Paragraph 4.8.6.

4.3.1 +~]. Thc shroud repair hardware shall be designed to horizontallysupport the top guide, core support plate, the fue) assemblies and theshroud head. Thc shroud repair shall bc designed to prevent vertical displacement of the shroud and shall provide its vertical support in the event of a complete H8 weld failure. The design features controlling thc horizontal and upward movements may bc diffcrcnt than thc features providing thc vertical support. The shroud repair shall be designed for a design life of 25 years (thc remaining design life of thc plant, plus possible life cxtcnsion beyond the current operating license), to include 20 Ffrcctive Full Power Years. All shroud repair hardware shall be designed so that they can be removed and rcplaccd. This is to provide full access to thc annulus area for

25A5588 SH NO. 5

~

REV. 2 possible future inspections and/or maintenance/repair activities that may prove necessary in the future.

5 " * 'P""5'" ' 5"' '" P' bending deflection greater than the deflection resulting from the limiting design upset condition, exclusive ofseismic events.

Th "5 '

5 5% for the springs.

4.3,S

.P..l ~. Th*5 55 *5 *5 h* P5 h d *'55'F.

operating temperature is 515-585'F. Operating temperature may be used for emergency and faulted evaluations.

h 4.8,8.2 RadiaQgn. The maximum neutron radiation level at the shroud repair hardware is 4x10" neutrons/cm>/sec, which will have no effect on material properties. This will'not afTect the properties of the shroud repair hardware over the remaining life of the plant.

4.8.4,1 The shroud repair hardware shall restrain the shroud during all of the load combinations in Paragraph 4.8.5. The allowable permanent deflection is dependent on the safety signiTicance of the portion of the shroud under consideration. The allowable permanent deflectio for those portions of the shroud, which affect control rod insertion, is given in Paragraph 4,2.S. For the portion of the shroud above H2, the allowable deflection is 2.8 inches, which assures that the core spray lines are not impacted by the shroud.

4.8.4.2 Tlie shroud repair hardware must provide features which facilitate handling during installation. The upper and lower springsshall be movable without removing the tie rod and without welding, in order to permit inspection of the reactor pressure vessel with GERIS 2000 and ABB RF012 tool.

4.8.4,8 All parts shall be captured and held in place by a method that will last for the design life given in Paragraph 4.8.1.

4.8.4.4 The design shall be removable to accommodate the installation of the recirculation nozzle plugs.

4.S.4.5 The design shall address the feasibility of installing the Overhead Grid Spray Sparger.

25A5585 sH No. 6 REV. 2

..5 ~Th*f 'l*d*li ~

• h h d p i I d The only earthquake is a design basis carthquakc {DBE), rcfcrcncc 2.S.a, Section iV-7.1.

Event Dead Prcssure OBE DBE WelSht (~ DBE)

Normal Vpsct Nortnal Upset Stcam line Exa lnlct Reclrc Redrc Normal ~

Upset Ii Upset F ~

Emergency I'mergency S'mergency l

S'ault Fault S Fault S

"~ Design Basis Load Contbinatlon as speclllcd ln reterencc Z3>.Secdon XVIE7 l.

4.5.5.1 The pressure differences for these events arc given in the Table below. Positive direction indicates that the pressure inside of the shroud is higher than that outside of thc shroud, and the prcssure below the core plate is higher than above the core plate.

Component Normal Upset Prcssure Steam Line Recirculation Prcssure (psi) LOCA Pressure Linc LOCA (psi) (psi) Pressure

.(psi)

Shroud Support 21.2 25,6 65.0 -125.0 Core Plate 15.9 18.5 41.0 -182.0 Shroud Head 59 8.9 22.0 7.0 4.5.5.2 A new seismic analysis based on the documents in Paragraph 2.5 shall bc performed, which includes the shroud repair. The shroud repair shall function for thc cntirc continuum from an uncrackcd shroud to a shroud with all horizontal welds (Hl-H8) containing through wall cracks, Therefore, multiple conditions must be'analyzed, for both thc OBE and the DBE

25A5588 sH No. 7 REV. R events, The minimum shroud conditions analyzed are as follows: an uncracked shroud with the installed repair, a shroud with a through wail 360 degree crack at the H8 weld with the installed repair, and a shroud with a through wall 360 degree crack at the HGB weld with the installed repair.

4,8.5.8 Two steady state thermal conditions shall be evaluated, The first is normal operation with the shroud and H8 support brackets at 5SO'F, and the stabilizer assembly at 515'F. The second condition is an upset transient (scram with loss of feedwater pumps) with the shroud and HS support brackets at 422'F, and the stabilizer at 300 F.

4.8.5.4 Asymmetric pressures in the annulus between the shroud and the RPV during the exit recirculation line LOCA event (Emergency 8 and Faulted 3) shall be considered.

4,8,6 ., The minimum safety factors (SFmin) for shroud displacement 4,8,7 vibration,

' 'he (Section 4.2.8) shall be 2.25 for normal and upset, 1.5 for emergency, and 1.125 for faulted.

shroud repair design shall consider potential sources of 4.4 M~~/. ASTM specification niaterial is acceptable for the Shroud Repair. CMTRs are required for all material. Material requirements are contained in the document in Paragraph 2.1 .l.c, 4.5 Zero leakage is not required. The design shall ensure that cracked welds do not separate under normal operating conditions. The desigrt shall account for leakage from the region inside the shroud into the annulus region during normal operation.

4.6 ~i~~

surfaces of Liquid penetrant examination shall be perforined on all final machined all new hardware and on all structural welds per ESOVP22A (Paragraph 2.1.1.a).

4,7 +h..tt;~n The fabrication requirements are contained in the document in Paragraph 2,1.1.c,

5. QUALHYASSURANCE 5.1 The shroud repair hardware components are Safety Related as referenced in Paragraph 2,1.2.b. Design, fabrication, installation, and other construction activities shall be controlled per a QA, Program, which satisfies 10CFR50 Appendix B, in order to assure safe and reliable components.