ML17285A634

Provides Addl Info Re Acceptability of Five Installed Items for Use in safety-related Applications,Per Insp Rept 50-397/89-21.Items Include,Potter & Brumfield Relays,Anchor Darling Valve Parts & 600 Volt or Less Fuses

ML17285A634
Person / Time
Site:	Columbia
Issue date:	07/20/1989
From:	Bouchey G WASHINGTON PUBLIC POWER SUPPLY SYSTEM
To:	Faulkenberry B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V)
References
GO2-89-120, NUDOCS 8907310070
Download: ML17285A634 (24)

Text

AC CK1ZRATED DlSTKBUTION DEMONSTRATION SYSTEM REGULATORY INFORMATION DISTRIBUTION SYSTEM (RIDS)

ESSION NBR:8907310070 DOC.DATE: 89/07/20 NOTARIZED: NO DOCKET CIL:50-397 WPPSS Nuclear Project, Unit 2, Washington Public Powe 05000397 AUTH. NAME AUTHOR AFFILIATION BOUCHEY,G.D. Washington Public Power Supply System RECIP.NAME RECIPIENT AFFILIATION FAULKENBERRY,B. Region 5, Ofc of the Director

SUBJECT:

Provides addi info re acceptability of five installed items.

for use in safety related applications,per Insp Rept 89-21.

DISTRIBUTION CODE: IEOID TITLE: General COPIES RECEIVED:LTR J ENCL (50 Dkt)-Insp Rept/Notice of Violation Response g 'SIZE: I NOTES:

RECIPIENT COPIES RECIPIENT COPIES ID CODE/NAME LTTR ENCL ID CODE/NAME LTTR ENCL PD5 PD 1 1 SAMWORTH,R 1 1 INTERNAL: ACRS 2 2 AEOD 1 1 AEOD/DEIIB 1 1 AEOD/TPAD 1 1 DEDRO 1 1 NRR SHANKMAN,S 1 1 NRR/DEST DIR 1 1-NRR/DOEA DIR 11 1

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1 NRR/DLPQ/PEB NRR/DREP/EPB 10 1~ 11 NRR/DREP/RPB 10 NUDOCS-ABSTRACT OGC/HDS2 2

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RES MORISSEAU,D 1 1 RGN5 FILE 01 1 1 ERNAL: LPDR 1 1 NRC PDR 1 1 NSIC 1 1 R

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S PIZASE HELP US IO REDUCE HASTE! CONI'ACT 'IHE DOCUMWI'ONHRL DESK, RDCN Pl-37 (EXT. 20079) KO ELXKBRXR YOUR MHE FKH DZPHUBUTICN LISTS FOR DOCUMEMI'8 YOU IXlNiT NEEDf OTAL NUMBER OF COPIES REQUIRED: LTTR 25 ENCL 25

ti WASHINGTON PUBLIC POWER SUPPLY SYSTEM V

P.O. Box 968 ~ 3000 George Washington Way ~ Richlaiid, "Wa'shinglon 99352 July 20, 1989 "ll: 0~

G02-89-120 Docket No. 50-397 Mr. B. H. Faulkenberry Deputy Regional Administrator U.S. Nuclear Regulatory Commission Region V 1450Maria Lane, Suite 210 Walnut Creek, CA 94396

Subject:

NUCLEAR PLANT NO. 2 LICENSE NO. NPF-21 NRC INSPECTION REPORT 89-21 ADDITIONAL INFORMATION

Reference:

1) Letter, B. H. Faulkenberry (NRC) to D. W. Mazur, dated July 3, 1989

2) Letter, B.H. Faulkenberry (NRC) to D.W. Mazur, dated July 14, 1989 Per the verbal agreement made in our telephone call on July 13, 1989 and the Reference 2) letter, we are providing additional information regarding the acceptability of the five installed items for use in safety related applica-tions, This response includes specific critical characteristics and verifi-cation methods.

This additional submittal provides details on how the current Supply System commercial grade dedication would be performed in accordance with EPRI Standard NCIG-07 guidelines. These evaluations also demonstrate the acceptability of the previous dedication efforts by the Supply System. Both this submittal and the previous submittal concluded that the actions taken by the Supply System were acceptable'e conclude that the items procured and installed are accep-table and of a quality level commensurate with the items importance to safety.

The Supply System has determined that some of the items under review were produced and supplied under 10CFR50 Appendix B gA programs. The application of these gA programs as accepted by the Supply System ensures that characteristics affecting form, fit and function are controlled to a design standard and that quality of the item can be verifi'ed. These items are now essentially bei ng treated as guality Class I items and do not require dedication. Additionally, both submittals were reviewed by our consultant of CYGNA Energy Service. They have reached the same conclusion. CYGNA has been involved in development of the EPRI standards for commercial grade dedication and in the NUMARC training for industry personnel.

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Page Two NRC INSPECTION REPORT 89-21, ADDITIONAL INFORMATION Commercial grade dedication activities have been evolving as. an area of grow-ing concern with the NRC and Utilities over the past several years.. The guidance that has been available to Utilities for commercial grade dedication is only now evolving. This is demonstrated by the issuance of the EPRI/NCIG-07 Standard dated June 8, 1988, the NRC conditional endorsement of the methods developed by this standard in March of 1989 (the same time as the SSOMI per-formed by the NRC at HNP-2) and by NUMARC endorsement of. this standard in March of 1989 with utility implementation planned to be complete by December of 1989.

For all of the five items of concern the original dedications were performed in advance of issuance of the EPRI Standard, the NRC Generic Letter (89-02) and the NUMARC endorsement of the EPRI Standard. These dedications were done by qualified engineers to assur e acceptability, and the judgements, conclusions and basis for dedication were reviewed by qualified engineers'n conclusion, itto isourthededication Supply System's position that process to provide improvements can and added assurance and have been made documentation of acceptability. It is also our position that these items are acceptable for use, that the dedications were acceptable as prepared based on existing acceptance criteria and that none of these items represent a violation of NRC regulations.

Should you have fur ther questions regarding these items we suggest a meeting would be the appropriate format to allow full exchange and resolution of con-cerns.

Very truly your s, G. D. Bouchey,, Directo Licensing 8 Assurance SHP/bk Attachment cc: JB Mar tin - NRC RV NS Reynolds - BCP8R RB Samworth - NRC Document Control Desk - NRC DL Hilliams - BPA/399 NRC Site Inspector - 901A

Page 1 of 12 ATTACHNENT 1 ITEN NO. 1: POTTER 8( BRUNFIELD RELAYS Item Description - Relay, control 8PDT contacts rated 0.8 amp 125VDC resistive, 125VDC continuous duty coil, NIL-R-19523A(SHIPS), operating voltage general service (80 to 110K), endurance category A, ambient temperature 65 degrees C, shock class 1 Additional Su 1 S stem Res onse These relays are "like for like" replacements for the origina'1 installed relays.

Critical Characteristics Determination Function of the Item Active electrical, this relay is energized on a "loss of offsite power" signal. Hhen picked-up it enables/causes a diesel auto start.

Failure Nodes/Effects - 1) Coil short circuit/failure of diesel to start. 2)

Coil open circuit/failure of diesel to star t. 3) Coil short to ground/failure of diesel to start. 4) Contact failure to change to energized state/failure of diesel to start. 5) Contact failure to change to de-energized state/makes, it difficult to stop DG, use of "emergency stop" switch will stop DG. Returning switch to normal would cause DG ,to star t, (acceptable, DG running is safe condition). 6) Contact chatter in energized state/could cause air start motors to stop operating. This is not considered a credible failure as the K16 relay which is in series with the K52 and K54 relays would also have to drop out and then air start motors (pneumatic) would stop. 7) Contact chatter in de-energized state/could cause diesel start (acceptable- DG running is safety condi ti on) .

Cri ti cal Characteri sti cs

1) Relay operation'al -endurance 500,000 operati ons

2) Relay operation frequency - 10 cycles per minute (minimum)

3) Ambient temperature - 65 degrees C

4) Seismic capability

5) Coil rated voltage 125 VDC

6) Coil operating voltage - 80 to 1105 of rated

2) Coil pick-up voltage 80% of rated (maximum)

8) Coil duty - continuous

9) Contact configuration - 8PDT

10) Contact rating - 0.8 amp continuous at 125 VDC resistive

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Page 2 of 12 r

Verification Method The manufacturer has a gA program which has been audited by Wisconsin Electric Power Company (audit A-Y-88-20). This audit determined that the manufacturer's program was acceptable.

The manufacturer is an approved vendor of these NIL Spec. Relays by listing on Federal ()ualified Products List (APL 19523-13).

The manufacturer has a ()A program which has been audited by Washington Public Power Supply System. This audit determined that the manufacturer is acceptable for the supply of commercial grade items for use in safety applications. The audit specifically covered the manufacturing of NDR relays to the requirements of NIL-R-19523A(SHIPS). This audit gives us reasonable assurance, that state-ments made by the manufacturer with respect to the design, testing and inspec-tion of the relay are correct..

MIL-R-19523A(SHIPS) requires qualification testing of the following critical characteristics and assurance that the above defined acceptance criteria are

. met. It also requires periodic testing and testing after "...any change in design which .affects performance characteristics." LNote that the following critical characteristics are considered performance characteristics by NIL-T-19523A(SHIPS)].

Relay Operational Endurance Relay Operational Frequency Ambient Temperature Coil Operating Voltage Coil Pick-up Voltage Coil Duty Contact Rating Seismic capability was originally established for the relay by testing. The applicable test report is Wyle Labs. Report 43735-.1, dated 9/20/78. This test qualified the relay as part of the panel E-CP-DG/EP1.

MIL-R-19523A(SHIPS) requires vibration testing of the relay after "...any change in design which affects performance characteristics." The test requires that the relay's resonant frequency be determined by test. This test requires a 0.010 single amplitude vibration applied for 15 seconds at 1 Hz. steps from 4 to 33 Hz. The relay is then vibrated from 4 to 50 Hz. (in 1 Hz. steps) for. 5 minutes at each frequency [amplitude as specified in MIL-R-19523A(SHIPS)]. The relay is then vibrated at its resonant frequency [amplitude as specified in MIL-R-19523A(SHIPS)3 for two hours. Although the amplitude/frequency combina-tions required by the tests do not attain the levels required by the OID (assuming that the relays ar e not rigidly mounted) the NIL tests are of such extended duration that is it our judgement that the NIL testing imposes suffi-cient design constraints such that similarity is established to the relays tested by. Wyle. Acceptance criteria in MIL-R-195523A(SHIPS) is no mechanical damage, contact chatter or failure to operate to either the energi zed or de-energized p'osition. Operation will be checked at each frequency.

Page 3 of 12 Coil rated voltage is specified in the purchase document and is stated on the relays nameplate. It is normal procedure for the receipt inspection to verify by comparison that the received item's nameplate data matches the purchase documents description. The audited manufacturer's ()A program gives us reason-able assurance that the correct nameplate is attached to the relay.

MIL-R-19523A(SHIPS) requires routine testing of each relay subject to MIL-R-19523A(SHIPS). This testing includes:

o Visual and mechanical examination to verify the materials, design, con-struction, dimensions, weight, marking and workmanship.

o Measuring the coil resistance value required by the design.

to determine if it is within 10K of the o Measuring limits.

of the insulation resistance to determine if it is within design o Measure of the pick-up and drop-out voltages at maximum operating tempera-ture to determine that they are within specified limits.

o A dielectric test.

The routine testing gives us reasonable assurance that the relays supplied are of high quality and that- the problem documented by Palo Verde Unit 3 LER, Docket Number 50-530, does not exist for the supplied relays. Control over relays with know deficiencies identified by specified data code has been estab-lished to assure none are installed, available for installation or procured by the Supply System. Post maintenance testing would also reveal this problem.

Contact configuration is verified at time of installation by post maintenance testing.

Per the INPO NPRDS records on 968 MDR relays there have been 35 failures based on records fr om 12/8$ to 10/88. The failure rate for this relay type is approximately 3 X 10 . This is considered by the Supply System to indicate a high reliability factor.

The Supply System has obtained certification that the relays supplied through Newark Electronics were manufactured by Potter 8 Brumfield to the purchase order requirements and the Potter 8 Brumfield gA program as verified by serial numbers on relays. A Supply System ()A Auditor has verified that the tests and inspections required by the MIL Spec. were accomplished on 2/10/87 or 2/12/87.

Conclusion The Supply System concludes that all critical characteristics of the relay have been verified by a combination of manufacturer's testing/inspection (Method 1*), Supply System testing/inspection (Method 1), audit of manufacturer (Method 2), performance history (Method 3) and approved 'vendor certification.

Therefore, the relay installed by MNR AV1684 is acceptable for its application.

• Exception methods as defined in NCIG-07

Page 4 of 12 ITEM NO. 2: ANCHOR DARLING VALVE PARTS Item Descriptions-Item 2-1 stem, yoke ASTM A-564 Gr 630 HT 1150 F, with collar (P/N 19-2-01) for 12" 900 lb. Anchor Darling double disc gate valve. Part No. 94-13401-19-2, Dwg. No. 94-13401, item 19-2.

Item 2 wedge, upper yoke ASTM A-216 Gr WCB with Stellite for 12" 900 lb.

Anchor Darling double disc gate valve. Part No. 94-13401-14-5, Dwg. No. 94-13401, item 14-5.

Item 2-3 - wedge, lower ASTM A-216 Gr WCB with Stellite for 12" 900 lb. Anchor Darling double disc gate valve. Part No. 94-13401-15, Dwg. No. 94-13401, item 15.

Item 2-4 - pin, wedge ASTM A-108 Gr 1018 (AISI 1018) for 12" 900 lb. Anchor Darling double disc gate valve. Part No. 94-13401-82-14, Dwg. No. 94-13401, i tern 82-14.

Additional Su 1 S stem Res onse The Supply System re-evaluation of these items has concluded that the items are available and were originally manufactured under the Anchor-Darling ()uality Assurance program. ~ We have revised this evaluation to require these parts to be supplied as equality Class I. ~ Anchor Darling has provided certification under a r evision to the original purchase order that the items supplied meet the requirements of this program. ~

The Supply System has audited the Anchor Darling equality Assurance Program and its implementation on numerous occasions. Anchor Darling is maintained on the Supply System's Evaluated Suppliers List (ESL) as a 10CFR50 Appendix B ()uality Class I supplier. The current full audit was performed in June of 1987, six (6) months before the subject parts were procured. This audit was the basis for inclusion of Anchor Darling on tHe Coordinated Agency of Supplier Evalua-tions (CASE) list of approved suppliers.

Additional inspections to assure implementation of their program occurred in February of 1988, April of 1988, June of 1988, October of 1988, December of 1988 and January of 1989. These inspections pr ovide additional assurance of supplier performance history.

Anchor Darling was audited by a team of auditors from 3 utilities on October 11 13, 1988 as a Nuclear Supplier equality Assurance Committee joint utility audit. This audi t also concluded that Anchor Darling's OA Program "was evaluated as effective and satisfactory". This audit specifically addresses piece parts supplied, including commercial grade parts.

The Supply System concludes these items 'are acceptable as installed

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Page 5 of 12 ITEM NO, 3: FUSES (600 VOLTS AND LESS)

Additional Su 1 S stem Res onse Standard Procurement and Use Policy No. 6, "Fuses (600 volts and under)" was issued on 6/30/87 to define procurement and dedication requirements for these items.

This policy was prepared by an engineer from the Supply System design engineer-ing organization, reviewed by an engineer matrixed to Plant Technical from design engineering, and approved by the Supervisor of Plant Technical Electri-cal Group and the Manager of Electrical/18C group of design engineering.

The Supply System policy and acceptance of the fuses in questions is based on an understanding of the manufacturer's processes, Underwriter's Laboratory (UL) activities and our experience with fuses.

To confirm our, policy we contacted the manufacturers in question on 6/27/89.

These conversations provided the following:

o Bussmann

1) Bussmann fuse production quality is governed by the Bussmann ()uality Assurance Manual.

2) The ()A Manual includes:

a. Physical checks to verify compliance to design requirements and workmanship,

b. 100K resistance checks, and

c. UL specified tests.

o Gould

1) Gould production testing is governed by their (}A Manual.

2) UL listed fuses are subjected to quarterly testing at the factory by UL.

Additionally, Supply System, Procurement QA made contacts with the QA 'Manager of Bussmann in June of 1985 to ascertain their testing requirements. The contact concluded that "in-process testing consisted of gaging for length and DC resis-tance testing at 100K of rated amperage". Also "On a random basis, ()C con-ducts audits of the in-process manufacturing. -

During these audits, fuses are sele'cted for destructive testi ng; i,e., subjected to anywhere from 130 - 500K of rated amperage. All Bussmann fuses are subjected to these tests."

Page 6 of 12 On 3/16/88 Gould-Shawmut was added to our "commercial grade" suppliers list based on review of a ()A audit performed by American Electric Power on 9/17/86.,

This audit concludes: "Gould, Inc. is an established manufacturer of circuit protection (fuses). Although Gould does not claim to do nuclear work, their'()A program is written to 10CFR50 Appendix B, ANSI N45.2 and 10CFR21. In general, Gould's OA program and implementation is adequate for the manufacture of fuses.

Both of these manufacturers produce UL listed fuses. UL independently tests these fuses to assure 'acceptability. The performance of these tests was audited .by Niagra Mohawk in April of 1988 and concluded UL listing was a "cri tical characteristic" of a listed product. Our review of this audit and UL standards concludes that UL activities constitute a significant quality assur-ance effort involving certification by an independent 'laboratory that the products meet the published industry standard. Observance of the requirements of the UL Standards by a manufacturer i.s a condition of continued listing of the product.

UL Standards specify requirements for, construction, dimensions and performance.

Performance testing is completed on samples of eacH type of material (or design). Tests include:

1) . Capacity test fuses must carry 110K of rating indefinitely.

2) Temperature test - fuse temperature must not exceed specified temperature limits when subjected to 110K rated current.

i Clearing time current test - fuses must clear (open) within specified time limits when subjected to'a combination of current values. Test values are 135%, 1505, 200$ and 500K based on fuse type.

4) Other design verification tests (i.e. interrupting ability, m~ximum energy, maximum threshold ration, let-through current and clearing I t.). ~

The Supply System's use of fuses is controlled by procedure (PPM 1.3.47) which requires evaluation of the fuse log and identification of repeated failures of fuses. . This evaluation would reasonably b'e expected to identify a concern with fuse quality.

PPM 1.3.47 requires:

1) Inspection of fuses for evidence of overheating.

2) Replacement of fuses wi th like in kind fuses.

3) Requirement to replace known incorrect fuses with the proper fuse as found.

Page 7 of 12

4) Requirement to log fuses as replaced to provide a record of fuse replace-ments.

5) Requirement to replace all fuses when one fuse is replaced in the circuit, i:e., both sets of isolation fuses, all three fuses in three phase appli-cations, both fuses for DC applications. This practice limits the possi-bility of fuse again causing a problem of inadvertent opening.

6) Requirement for checking fuse integrity after installation.

7) Requirement for a technical review of replacements every three months to assure fuse configuration is being maintained and to identify recurring failures or other design problems.

Critical Characteristics Oetermination Functions of the Items - Fuses are used in safety related equipment electrical circuits to prevent severe equipment damage in the event of faults or shorts, to protect 1E motors and transformers from overloads and to provide isolation of non-1E circuits from 1E circuits. The fuses have been sized with the consi-deration for the total loads the fuse would be expected to experience under all conditions. This sizing is done in a conservative manner (at least 125K of full load current) to preclude the event of a fuse opening in any condition other than a real fault or overload, and minimize impact of commercial product tolerances. ~

Failure Nodes and Effects Fuses have two failure modes of concern: I) inad-vertent opening with no fault or overcurrent condition and 2) fai lure to open when a fault or overload exists. ~

Inadvertent opening could result in loss of downstream safety related equipment operability. . Random loss of a fuse in one division and subsequent loss of downstream safety related equipment would not affect the ability of the redun-dant division's equipment to perform the required safety fuctions. In all cases this loss of function would be repairable by fuse replacement in a mini-mal amount of time.

Failure to open on a fault or overcurrent condition could cause the upstream circuit protection devices to open potentially resulting in loss of additional safety related equipment operability of the same division but would not affect the ability of the redundant divisions equipment's ability to perform the required safety functions.

Critical Characteristics Critical characteristics for fuses include manufacturer's part number and

.current rating, and UL listing where fuse is UL listed.

Page 8 of 12 Yerification Methods Industry Standards govern the manufacture of fuses. These controls provide an acceptable level of assurance that the items have sufficient quality. Audi,ts of UL activities described above provide further assurance of product accep-tabi lity (Method 2). Historical performance of fuses provide an additional level of assurance (Method 4). Receipt inspection verifies proper rating, part number, and UL listing where fuse is UL listed by comparison with procurement requirements (Method I). Controlled application of fuses and fuse trending program provide further assurance of fuse acceptability.

Conclusion Our acceptance of fuses has not been based solely on installation checks to verify fuse quality. Tests at the time of installation verifies that the fuse replacement has restored circuit integrity. Testing which will .verify that a fuse wi 11 perform in a manner consistent with its design parameters will generally result in destroying the fuse. We are further unaware of any industry consensus concerning receipt testing of fuses.

Fuses are relatively simple devices which operate on physical principles that are well characterized. We know of no basis for doubting that modern designs can perform their intended function. Application of specific fuses by design engineers includes adequate margin to account for production tolerances. ~ Our experience with these fuses has not identified a quality concern.

The Supply System is aware of a utility doing extensive inspection of procured fuses and'are rejecting significant levels of fuses based on failure to pass a load test. These failures have primarily been with non UL listed fuses. ~ We have been in contact with this utility and are reviewing their program to see if a similar or joint effort is warranted. We are also aware that these tests are difficult to perform without a controlled environment and the results of this testing may be questionable.

The Supply System concludes the installed Fuses are acceptable as installed'

Page 9 of 12 ITEN NO. 4: PRESSURE SWITCH Item Description Switch, pressure, range 10 - 250 psi, differential 23 - 25 psi, maximum allowable pressure 300 psi. double pole double throw contacts rated 10 amps at 600 VAC, with form W-1 (NENA 4 watertight enclosure). Square D Part number 9012 ACW-29.

Additional Su 1 S stem Res onse These switches were procured as commercial grade because the Supply System understood the manufacturer no longer offered them as (}uality Class I. We have subsequently learned that the manufacturer always offered these 'tems as

(}uality Class I but was accepting orders only for replacements. We expect to revise our procurement evaluation to a (}uality Class I purchase, audit the manufacturer and add them to our ESL.

The manufacturer's (}uality Assurance department stated that these switches were made under the same (}A program even while not offered as (}uality Class I.

Critical Characteristics Determination Function of the Item - These pressure switches monitor the air pressure in the Division I and 2 diesel generator air receivers. Their function is to start and stop the non safety related air compressors to maintain a specified range of air pressure in the air receivers and provide low air pressure alarms. The switches perform a passive mechanical integrity function (prevent air leakage from the air receiver due to switch leak).

Failure Nodes and Effects - In the event of loss of mechanical integrity of the switch the switch will provide a start signal to the compressor upon reaching the low setpoint. The makeup capacity of the compressor is greater than the leakage capacity through the switch so this is of minor significance.

In the event of failure of the pressure switch to start the compressor at the low pressure setpoint due to contact seizure, binding or other causes, the pressure switch will provide a low pressure alarm to the control room which will allow the operator to manually start the air compressor.

. Nechanical integrity is the only concern for seismic qualification, contact chatter does not pose a problem in this application.

The switch can easily be serviced without declaring the DG inoperable, there is a totally redundant system in service which provides sufficient air for multiple start attempts.

This switch has minor safety significance due to the failure effects and the redundancy provided.

Page 10 of 12 Critical Characteristics

1. Range 10 to 250 psi

2. Contact rating - 10 amps 600 YAC

3. Part No. 9012 ACH-29

4. Contact Configuration - DPDT

5. Differential 23 - 25 psi

6. Seismic integrity Yerification Methods Items 1, 2, 3, and 5 were verified by comparison of nameplate/tag data with the procurement requirements, as part of standard receipt inspection and have been reverified on installed switches (Method 1).

Item 4 was verified as part of installation checks, calibrations and post maintenance operability tests (Method 1). Installation included QC inspection of the work performed.

Item 6 is assured by the switch being a like for like replacement. The manufac-turer has stated that no significant design changes occurred which would effect the mechanical integrity of these switches. Original switches were qualified by Supply System in Qualification Information Documentation (QID) file 256015.

Additionally'he switches have a pressure rating such that a safety margin greater than two times exists.

The Supply System has contacted Stoneway Electric and obtained a copy of their invoice for the switches supplied by Square D Company which provides trace-ability to the manufacturer.

These verifications provide adequate assurance the switches are acceptable.

Conclusion The Supply System concludes tha't the switches as installed are acceptable.

Page 11 of 12 ITEN NO. 5'ETAL 0-RINGS Item description Item 5 O-ring, metallic, 2.262" OD (as measured prior to plating) 0.125" free height 0.010" wall thickness, Inconel X-750 w/0.001" minimum silver plate, American Engineering P/H 2262-125X010 AMS5582Ag.

Item '5-2 - O-ring, metallic, 1.656" OD (as measured prior to plating) 0. 125" free height 0.010" wall thickness, Inconel X-750 1656-125X010 - ANS5582Ag.

Addi ti onal Su 1 y S stem Res onse Dedication requirements are stated in Design Change Package DCP 83-0056-OA dated 4/22/85. A CNTR was not required for the metal O-rings-, but was received .

with the purchase as it is that vendor's practice to always provide the CNTR from the material supplier as a courtesy to the purchaser.

Generation engi neering has determined that the effects of temperature cycling on these 0-ring seals are negligible in this application.

These 0-rings are specifically exempted as pressure boundary parts by the ASNE Code. However to assure all possible safety functions are evaluated the Supply System provided the following evaluation.

Critical Characteristics Determination Function of the Item -, These 0-ring seals constitute a part of the containment pressure boundary between ECCS system relief valves and the containment suppression pool. The discharge strainer in the suppression pool is below the water level. The sole safety function of the 0-rings is to provide a pressure tight seal at the discharge flange of RHR-RV-18.

Failure Modes/Effects Seal leakage or failure is the only plausible failure mode.

1)'elief Valve Opera'tion Seal failure would cause a small leak in the RHR heat exchanger room if any of the various system relief valves sharing. the common discharge path to the suppression pool were to'ift. The leak would stop as the valve re-seats.

2) LOCA Event The containment pressure that would be required to push suppression pool water from 466'-3/4" elevation to a relief valve height of 585'-9/16" is approximately 51.4 psi, which is higher than the 45 psi containment design pressure and significantly higher than the highest postulated accident pressure in containment. The water seal would therefore mai ntai n containment integrity. If the water seal were lost, the effects would be insignificant due to the small size of the leak.

Page 12 of 12 Cri ti cal Char aeter i sti cs

1) The 0-ring diameter must be of correct size to properly fit into the associated groove on the flange.

2) The 0-ring height (tube diameter) must be of correct size to provide a seal when installed.

Verification Method DCP 83-0056-OA required a "Type 8" leak test in accordance with'0CfR50 Appendix J t'o determine adequacy of installed material and workmanship (Method 1). This was performed at installation and documented on the installing MWR.

Seal integrity is tested periodically pursuant to 10CFR50 Appendix J.

Conclusion The Supply System concludes that the 0-rings are acceptable, as installed.

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