ML20033H113

Summary of CRGR Meeting 179 on 900207 Re Proposed Bulletin on Loss of Fill Oil in Transmitters Mfg by Rosemount & Review of Proposed Generic Ltr to Correct Deficiency in BWR Critical Power Ratio Calculations

ML20033H113
Person / Time
Issue date:	03/30/1990
From:	Jordan E Committee To Review Generic Requirements
To:	Taylor J NRC OFFICE OF THE EXECUTIVE DIRECTOR FOR OPERATIONS (EDO)
References
NUDOCS 9004180191
Download: ML20033H113 (54)

Text

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+ MEMORANDUM FOR: _ James M.' Taylor Executive Director for Operations FROM: Edward L.' Jordan, Chairman Committee to Review Generic Requirements

SUBJECT:

MINUTES OF CRGR MEETING NUMBER 179 -The Committee; to Review Generic Requirements (CRGR) met on Wedries' day, February 7,1990 from 1:00-4:30 p.m. The following items were addressed at-the meeting-1. S. Newberry (NRR) and C. Berlinger (NRR) presented for CRGR review a proposed bulletin on Loss of Fill-011 in Transmitters Manufactured by. Rosemount. The Committee recommended issuing the bulletin subject to .several revisions to be coordinated with the CRGR staff. This matter is-discussed in Enclosure 2, 2. D. Fieno (NRR) and L. Phillips (NRR) presented for CRGR. review a proposed generic letter to correct a deficiency in BWR critical power ratio calculations involving channel box low. The Committee recommended in favor of issuing the proposed positions,. subject'to a number of revisions, in the form of a bulletin. The revised proposal would be circulated to members on a negative consent basis. No further meetings-were planned. This matter is discussed ^in Enclosure 3. In accordance with the E00's July 18, 1983 directive concerning_" Feedback and Closure of CRGR Reviews," a written response is required from the cognizant. office to report agreement or disagreement with-the CRGR recommendations in these minutes. The response, which is required within five-working days after-receipt of these minutes, is to be forwarded to the CRGR Chairman and,if there is disagreement with CRGR recommendations, to the EDO for decisionmaking. Questions concerning these meeting minutes should be referred to Dennis Allison (492-4148). /. Jordan,Chabman a Commit e to-Review Generic Requ rements

Enclosures:

As stated cc: See next page ()bb,\\ @ okie 06 pf a\\\\ D (

o ) James M. Taylor 2-s L cc w/ enclosures: Commission (5) SECY s J. Lieberman P.' Norry D. Williams Regional Administrators CRGR Members i ? a .i ) 1 ~ 1. l + l l l- -i

4-f 4 l .t Enclosure'1 Attendence-List for CRGR Meeting Number 179 CRGR' Members E.-Jordan S. Lewis (for J. Moore) J. Sniezek i J.-Murphy (for D. Ross) L. Reyes ~ G. Arlotto NRC Staff J. Heltemes-J. Conran D. Allison E. Rossi A. Thadani C. Berlinger S. Newberry J. Ramsey-V. ' Thomas-J. Mauck. L. Whitney P. Khadambi L. Phillips D. Fieno R. Jones l l 'I l l

.E.) ~l . to the Minutes of CRGR Meeting No. 179 Proposed Bulletin on Loss of Fill-Oil in-Transmitters Manufactured by Rosemount F February 7, 1990 .i TOPIC f C. Berlinger (NRR), S. Newberry (NRR), A. Thadani (NRR), and E.- Rossi (NRR), presented for CRGR review a proposed bulletin on' loss of fil1-oil in transmitters manufactured by Rosemount. i Rosemount transmitter Models 1151, 1152, 1133 and 1154 were widely,used in the nuclear industry. It had been reported that they.were susceptible to failure due to loss of full-oil from the transmitters' seals sensing modules. In' addition, transmitters of other manufacturers that;use the.same components' might be susceptible to failures from the same cause. The proposed bulletin would request that licensees identify the subject transmitters, review experience from~ symptoms of oil leakage.,'In this-1 process, licensees would develop acceptance criteria and replace transmitters when needed. Transmitters from suspect lots (which were known.to be highly susceptible to failure) would be replaced on an expedited ~ basis. Licensees-were also requested to develop and maintain bases for continued operation for i the time from identification of oil leakage symptoms until transmitter i replacement. t Licensees would be requested to confirm compliance with the: above actions. Further, they would be requested to-identify all transmitters indicating symptoms of oil leakage (or confirmed failure) for staff review to determine ~ failure rates. They also would be requested to identify. transmitters from suspect-lots. For future symptoms or failures which were not reportable to NRC, licensees would be requested to document and maintain records.of appropriate information. The slides used by the staff in its presentation are provided as Attachment 1 to this enclosure. BACKGROUND l The package submitted by the staff for CRGR review of:this matter was transmitted by a memorandum dated: January 29, 1990, from J. Sniezek to E. Jordan. The package-included: -(1) The proposed bulletin', and' e (2) Contents of packages submitted to CRGR. The Committee was also provided with two sets of comments that had been received from industry groups: L 1. A letter dated February 6,.1990, from S. Wanek, Rosemount,- to !~ C. Berlinger, NRC (Attachment 2 to this enclosure), i 2. A letter dated February 7, 1990, from N. Reynolds, NUBARG, to l C Berlinger, NRC (Attachment 3 to this enclosure)

f _ ;. l-J CONCLUSIONS / RECOMMENDATIONS 3 The Committee-recommended issuing the proposed bulletin subject to the following revisions: 1. The required actions of the bulletin should be. limited to R'osemount I Models 1153B,.1153D, and 1154. This.was the case because there were relatively few known failures in other models and-there were design-1 differences that should make other models less susceptible to the specific concern being addressed.

2..

The bulletin should indicate' that th'e'NRC'was requesting enhanced surveillance consistent with the recommendations of Rosemount, except that the NRC had not accepted Rosemount's ". infant mortality" rationale for excluding transmitters -that had already been in service under'certain: t time and pressure conditions without failing. 3. The bulletin should encourage industry. organizations to-take the lead in-compiling the information on operating experience that would be needed. I i for closure.of the issue or relaxation of the enhanced surveillance requirements. ] 4. The bulletin should make licensees aware that the NRC was continuing to review operating experience with other Rosemount Models (such as 1151 and i 1152) and-the requirements of the bulletin might'be extended-to those models in the future. Licensees should be encouraged (but not required) to report all failures to Rosemount and to include all transmitters in enhanced surveillance programs. =, i 5. The discussion should be expanded to emphasize the potential risk of. l undetected and common mode failures as a basis for taking the actions'in - the bulletin. The revisions should be coordinated with the CRGR' staff. No further review was anticipated. It was noted that this action was considered to be justified as a compliance backfit. I t ~

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BCS-h PDR .3 .; i '( s 4egon File Note and Retum 'j Appresel - For Cleerence Per Conversation Aolleeuented For Correction Propero Reply Circulete For Your informath See Me munment invoetisste sisneture Coordinellen Justih REMARMS This previous Central File material can now be made publicly available. l \\ - 00 NOT use this form es a RCCORD of approvals, concurrences, disposals, ekerencee, and similar actions fit 0M:(Neme, org, symbof. Agency / Post) Room No.-Bidg. / O /1 8 Phone N4'/ 9 P 1

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i Material Related to CRGR Meeting No. 179 to be made Publicly Available 1. Memo dated March 30, 1990 for.J. Taylor from E. Jordan,; subject: Minutes of CRGR Meeting Number 179, including two enclosures which were. not previously released:

a., a-summary

liscussions of proposed bulletin on loss of fill-oil in transmit.tes manufactured by Rosemount, including 3

- t attachments, i

b., a summary of discussions of a proposed generic letter' to correct a deficiency in BWR critical power ratio calculations-involving channel box-low, 1 attachment.

2. Memo dated January 29, 1990 for E. Jordan from J. Sniezek forwarding review materials on a proposed bulletin of loss of fill-oil:in transmitters manufactured by Rosemount. Memo dated January /)*6',1990 for E. Jordan from J. Sniezek forwarding 3. review materials on a proposed generic letter to correct a dpficiency in BWR critical power ratio calculations involving channel boxdow. i Sent to PDR on: 4/27/90 l 4 1 I i m e 4*v-yv m-W W

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s4 ,1 ' k C L L/if ? ,.I 1 4 1 f 4 t PRESENTATION TO THE CRGR. FEBRUARY 7 1990 i LOSS OF FILL-0IL IN TRANSMITTERS MANUFACTURED BY.ROSEMOUNT l- 'l l l l'

I SLIDE 1 l 1 o PRINCIPLE OF OPERATION OF VARIABLE CAPACITANCE TRANSMITTERS SENSING DIAPHRAGM IS PLACED BETWEEN A SET OF PARALLEL CAPACITOR-l ' PLATES l CAPACITOR IS FILLED WITH OIL WHEN PRESSURE'IS APPLIED T0: ISOLATING DIAPHRAGM A FORCE-IS' TRANSHITTED THROUGH OIL CAUSING SENSING DIAPHRAGM TO DEFLECT DEFLECTION OF SENSING DIAPHRAGM CAUSES CHANGE IN DIFFERENTIAL CAPACITANCE CHANGE IN DIFFERENTIAL CAPACITANCE IS CHANGED TO OUTPUT CURRENT: (TYPICALLY 4 TO 20 OR 10 TO 50 MILLIAMPS) l t i I-I l

SLIDE 2 l 0 DESCP,1PTION OF LOSS OF FILL-Olt PHENOMENON l OIL LEAKS FROM. SEALED CAVITY LEAK IS NORMALLY INTERNAL TO SENSING MODULE l DESTRUCTIVE EXAMINATION OF SENSING MODULE IS NORMALLY REQUIRED T0 CONFIRM OIL LOSS s T l l l t S - - ~

.l-f ~' SLIDE 3 o SAFETY SIGNIFICANCE TRANSMITTERS ARE UTILIZED TO MEASURE PRESSURE, LEVEL, AND FLOW TRANSMITTERS ARE RELIED UPON TO PROVIDE INPUT T0: REACTOR CONTROL AND' PROTECTION SYSTEMS TRANSMITTERS ARE RELIED UPON T0' PROVIDE INPUT TO THE ENGINEERED s SAFETY FEATURES ACTUATION SYSTEM TRANSMITTERS WOULD BE RELIED UPON BY OPERATORS WHEN TAKING ACTIONS' TO MITIGATE THE CONSEQUENCES OF AN ACCIDENT PERFORMANCE OF. TRANSMITTERS THAT ARE-LEAKING FILL-Olt GRADUALLY DETERIORATES AND MAY EVENTUALLY LEAD TO FAILURE TRANSMITTER FAILURE DUE TO LOSS OF FILL-0!L MAY' NOTl BE. DETECTABLE DURING REACTOR OPERATION o e ? b ., +,.

s 1 SLIDE 4 o EXTENT OF LOSS OF FILL-0IL PHENOMENON LOSS OF FILL-Olt PHENOMENON IS CURRENTLY CONSIDERED BY-THE STAFF TO . ? BE APPLICABLE TO MODEL 1151, 1152, 1153, AND 1154 TRANSMITTERS AND SENSING MODULES MANUFACTURED BY ROSEMOUNT CERTAIN MANUFACTURING LOTS OF MODEL 1153 AND 1154 TRANSMITTERS HAVE BEEN IDENTIFIED BY ROSEMOUNT AS HAVING EXHIBITED A-HIGH FAILURE FRACTION r THE STAFF IS NOT AWARE OF INFORMATION THAT INDICATES THAT TRANSMITTERS SUPPLIED BY OTHER MANUFACTURERS ARE CURRENTLYJ EXPERIENCING A SIMILAR PHENOMENON t e f -~~-s e e e v

1 SLIDE 5 o CORRECTIVE ACTIONS REQUESTED IN BULLETIN i IDENTIFY POTENTIALLY SUSCEPTIBLE TRANSMITTERS IN USE IN SAFETY-RELATEDANDATWS-(10CFR50.62) SYSTEMS i-ESTABLISH AND IMPLEMENT A PROGRAM TO MONITOR THE IDENTIFIED ~! TPANSMITTERS REPLACE AT THE EARLIEST APPROPRIATE OPPOPT'JNITY THOSE TRANSMITTEP.S THAT ARE FROM THE MANUFACTURING LOTS THAT HAVE EXHIBITED 'A HIGH FAILURE FRACTION AND ARE UTILIZED IN THE RPS OR ESFAS f l l

q SLIDE 6 o' COMMENTS RECEIVED FROM INDUSTRY ON LRAFT BULLETIN INCLUSION OF MODEL 1151 AND 1152 TRANSMITTERS INTO THE ACTIONS RE0 VESTED -f i APPLICATION OF ACTIONS REQUESTED TO TRANSMITTERS ThAT UTILIZE- -FILL-0IL BUT ARE.NOT;-MANUFACTURED BY ROSEMOUNT RESPONSIBLE EFFORT TO ADDRESS DIFFICULT PROBLEM, BUT HAS TECHNICAL-INADEQUACIES THAT NEED CLARIFICATION i i l t l l l l

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PROCESS INPUT i- ~ PROCESS INPUT iud k N.i$$ 'NN .n m-ha hI kh II< m# ea f r g* wj- \\ / 3 e \\ 5 \\ h@ ISOLATING ISOLATING e 5 DIAPHRAGM DIAPHRAGM N \\ u L i FIXED PLATE FIXED PLATE ? SEPSING ' DIAPHRAGM i \\ l I r I l'

l: .ja' Figure 1 - Utility Decision Tree-t Determine all1153 & 1154 transmitters; received

• I t-YES J

No safety concern Do you how any1153 Series A units?.- 1 No-4 g No current safety .YES Are transmitters concern. Return to C spares or not Rosemount for in-service?. module replacement Train YES technicians / operators. Is' operating pressure less than 250 psi? on low oil symptoms and continue operation h P YES Are transmitters in stand by service? U ; YES . Is the pressure x time = > 60k psi-mo(all R3-5). >60k psi-mo(AP/GP R6-10) >130k psi-mo(DP/HP R6-8) ? I NO .-y Continue to operate using diagnostic guideline (s) - until critical pressure x time in service value is met or-untiltransmitter is replaced. 'Model 1153 and 1154 with serial numbers less than 500,000 containing the original sensor module Plant specific analysis of application and transmitter diagnostics - should be considered .,,,.J._ __,m.,

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i, Figure 1-Utility Decision Tree Determine all1153 &

1154 transmitters received

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.u YES Do you have any1153 No safety concern Series A units? .. NO, g No current safety 'YES - Aretransmitters concern. Return to spares or not Rosemount for in service? module replacement . No p technicians operators is opera n8 p,, n psi? on low oil symptoms and continue operation NO' ] h U YES i Are transmitters in m l stand-by service?. U n YES la the pressure x time l = > 60k psi-mo(all R3-5) - >60k pslano(AP/GP R610). >130k psi mo(DP/HP R6-8) ? p. NO Continue to operate using diagnostic guideline (s) t until critical pressure x time in service value is met or: untiltransmitteris replaced.

• Model 1153 and 1154 with serial numbers less than 500,000.

containing the original sensor module Plant specific analysis of application and transmitter diagnostics-should be considered ..-.-.s

=. MAXIMUM TIME IN SERVICE .1 1 7 / 10 - / r/ / / /

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/ / 7 / / / 7 / / / 8~ / / / /. / / - / / i- / / r/ / / >.y / / / / / s _. / / / / / w 8 / / / / / / 7 / / / / ^~ / / / / / / / / / / / / 4-i / / / / / / ~ / / / / / / '~ 7 / / / 7 / / / 7 / / / / / / / / / ~ 7 / / / / / / / / / / / / / / / / / / / \\ ' - / / / / / / / / / 7-r / r / /'/,r/ r/ / / / / / / / r/ / / / / '/ / / / / / / / / / './. ! / / /,, / 0 i i i. i- .. i p i.. i i. _ i._ i i i 0~ 3 6 9 12 15 181 21-24 -27 30 33 36: 39 '42 '45 '48' 51 54 ~ MONTils -This visual aid is.one of ten used-to support ai-verbal presentation.- Interpretations ~of one or more of-thh-overheads without.the accompanying verbal discussion.may' lead-to, inappropriate conclusions.. ~ i -pleann direct any questions regarding thiscinformation.to..Rosemount:Inc; Steve Wanek.'(612) 828-3674. .4 -.. ~,

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= t. f E B.~ "' ~ '30.I1:SO' BC. .p; . pAGE.02; w omets Bishop, COOK. PURCELL & REYNOLDS ~ Woo L $TRttT N.W. WASHINGTON. o.C. RoooSQS02 ? (202)371570o l C -..ma a omwr om trum, eem neeuw w .tsacom soman e o. February 7, 1990' A.,m % ~v. .s Mr. Carl H. Berlinger Chief, Generic Communications Branch' [ United States Nuclear Regulatory. commission 4 + Washington,-DC 20555: J Subj: Comments On Draft NRC Bulletin On Loss Of Fill-Oil In' Rosemount Transmitters

Dear Mr. Berlinger:

The Nuclear Utility'Backfitting and Reform Group -(NUBARG) ~ and the Nuclear Utility Group On Equipment Qualification (NUGEQ) provide the following comments _on the above-referenced draft-. Bulletin. Generally, we. agree with the purpose'of:the subject draft Bulletin; however, our members are concerned that.the: current scope of the draft Bulletin..and the absence of proper backfitting justification will cause-thio' draft Bulletin'to dilute a meaningful effort on the part ofuthe industry to effectively address this concern. Rather than providing you with rodundant observations,1we-begin by stating that our members wholly Anderse the comments, already provided by NUMARC, especially.with regard to the-inclusion of:Model 1151 and 1152 transmitters.. These models; utilize elastomeric o-rings,.rather than' metal-process o-rings,. which do not create the additional stresses needed-to cause-the glass to metal seal failure mechanism. L In addition, our members believe that the Staff'.should reconsider the tremendous amountLof research dataEcompiled by-Rosemount which indicates that transmitter failures can-be correlated to certain " suspect" manufacturing lots havingla failure fraction substantially higher thuntthat of all other l manufacturing lots.. Rosemount hasfalsoLeompiled data whicht demonstraton'that the failure rate for. transmitters isihighest when the transmitters are subjected to high static pressure over a certain period-of time. The. time.in service required toireach th'e-peak failure rate-decreaseswith static pressure r-Pailure i rates drop exponentially with time in service, reaching-acceptably low levelu at times that can be predicted by a product (

FEB .7 f90.11:253 .BC _A PAGE.03f - 1 f. . i lj of pressure and time. We bring this to your attention because many of our members do not believe that. transmitters which have been in service over a long period of time at. full system pressure should'ba required to be replaced-unless there is an..__. -. j indication of fill-oil leakage. 4m2 mv Nevertheless, the draft Bulletin would request licensees to' take : j the-following actions: o ..,,,s wwg..,.,,...,. -. u, g e.. % ~

j 1.

Identify'all Rosemount Model 1151, 1152, 1153,. 1154 transmitters (except-Model 1153 and 1154 Mba transmitters manufactured after July -11, 1989) 1 wh'ich; are in safety related systems or ATWS systems; 2. Review plant records to' determine =whether.any_of.:the4.- identified transmitters exhibit signs of' fill-oil leakage; 3. Develop an enhanced surveillance program toLmonitor' I transmitters for symptoms of loss of fill-oil; 4. Identify whether any Model 1153 and_1154 transmitters from the high failure rate lots are present: 5. Justify continued operation until high failure rate lot transmitters used in the reactor protection system i or ESFAS can be replaced;Eend L i t 6. File requested' reports. The NRC Staff indicates that.the above actions constitute i a backfit under 10 C.F.R. 5 50.109, but that a full.backfit ~ analysis is not required because the backfit is necessary to bring facilities into' compliance with existing-requirements. The requirements cited include General Design Criterion 21', which requires that protection systems be designed for-high functional reliability and with sufficient capability to allow periodic -testing of their functioning when the reactor is in' operation, L and IEEE-279 which requires that means.he_pr.qyided for checking operational availability of: input sensors during. reactor. operation. L In general, facilities already comply with such' system i design and surveillance requirements. At issue is'whether r facilities should develop new programs to address high-failure-rato transmitters installed within thoso systems. We concur ~that transmitters known to be_ susceptible to unacceptable failure rates should be identified and replaced. Therefore,. compliance is appropriate for actions 1-6 above, but only for transmitter ~' M6diilir"n33 and T154 Prom the-known high-futivre rate-16. - ) ~ Transmitter Models 1153 and 1154 from Lots not having high failure raten should.be excluded from the requested actions, as i

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u.. H-w 6 E. 0 4 _.. 2 ... 7 i L should transmitter Models ll51_and 1152. We donnot believe an adequate basis has been shown to conclude.that these transmitters are susceptible to unacceptably high failure rates..Therefore, there Lis no-justification for indicating that protection sgEgpas_ containing these transmitters are not in compliance with: existing _ regulations. Accordingly, a backfit analysis under-10 C.F. i 50.109 is appropriate prior to imposing on licensees the A'e'. y.,.w. r u above-describedirequirements for these transmitters.. l-Use off.hNc'o$p$5ahc ex'6ehlon.to"Shaekfitti ~ section 50.109 (4) (4 ) (1), is not justified'because of the

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o L demonstrated high reliability of Rosemount transmitters, ewsh,-L; L for the high-failure-rate manufacturing lots.: An:appropria W "-- backfit analysis would likely indicate that the cost of including other transmitters in the actions required by this draft Bulletin-far exceed the benefit.which may result from the actions - i, Accordingly, we-recommend that only the known'high. failure-rate transmitters be. included in the scope of the-Bulletin. In the alternative, a backfit analysis should-be performed prior to including transmitters other-than the-high-failure-rate manufacturing lot transmitters, Models~1153 and l 1154, in ' the actions required. We understand-that the NRC would like to identify failure modes of all Rosemount'-transmitters, t i.e.,-those having' acceptably low failure rates, however ~a less manpower intensive and costly. program.vould be more appro,priate than the program of the draft Bulletin. To!this end, we recommend a bulletin notifying licensees to be aware of failures of Model 1151 and 1152 transmitters, and requesting licensees, for example, to return failed transmitters to Rosemount for testing. Sincerely, -N cholas S. nolds John A. MacEvoy-Counsel to;the Nuclear -Utility Backfitting And-Reform Group and the Nuclear Utility Group on-t Equipment Qualification cc: Dennis P. Allison .--..,-~~ --,

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e February 6, 1990 k i Mr. Carl-H. Berlinger Generic Communications Branch. Division of_ Operational Events Assessment-Office of Nuclear Reactor Regulation j Nuclear-Regulatory Commission-Washington, D.C. 20555 1 l t

Dear Mr. Berlinger:

l i l We appreciate this opportunity to comment on the-draft NRC; -Bulletin titled " Loss of. fill-oil in; Transmitters manufactured by Rosemount". Due to the. time restrictions involved, our response is provided in summary fashion and' l with limited detail. Rosemount has.two major concerns with l L the draft bulletin:

1) Rosemount Models 1151 and 1152 are.ossentially free of the glass-to metal seal failure found with certain of the 1153 B & D and 1154 models.

For this reason,-Rosemount believes that the Model 1151, 1152, and 1163A trannmitters :chould not be included in the bulletin. I t

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2) Transmitters which"have exhibited integrity-through f

an' operating time at pressure history have proven -r U they_areLfree of the glass ~to metal seal failure mechanism. We believeLthat intensified monitoring-j_. is.not-required for these transmit.ters.

1 In addition to'these major concerns which will? address.

I first, there are.certain technical inaccuracies and statements that could be misleading which are addressed-beginning on page S. J The~ definition of " loss of. fill oil" used in the Draft is'~ somewhat ambiguous. The gl' ass'to. metal ~s7al failure is:the only non-random failure mechanism which has been identified. Rosemount therefore limits the definition-of oil loss to this glass to metal. seal failure mechanism. This problem is only applicable to Model 1153 B&D and 1154 units. This position is supported by the following information: i f o only Model 1153 B&D and 1154 transmitters"use rigid stainless.uteel o-rings. Rosemount has: determined: i that force due to the stainless steel o-ring;is.the-primary cause for=the glass to met.a1 seal failure. This rigid metal o-ring is required to meet unique nuclear service requirements. Predecessor Models l 1151, 1152, and 1153A utilize a flexible elastomeric o-ring which generates a much-reduced-force. Page 2 2 m --.4--*.,e.. .--c-%,

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o Rosemount has identifiad ono Mode 1L1152 loss of oil ~ l failure of unknown mechanism from a population _ot-I over-18,000 shipments. worldwide. This single l failure occurred in 1985 and cannot be classified as-i a confirmed glass to metal' seal failure.- The Model ~ 1152 is under the.same failure reporting L l requirements in the U.S. as the Model 1153 and-1154. The noted difference in failure rate serves to support the technical position regarding the t stainless steel o-ring as a primary cause. o The Model 1153 serios A, which used an clastomeric o-ring, has had no confirmed glaun'to metal failures, again supporting the previously stated l technical position, o We have only 26 confirmed Model 1151 glass to metal seal failures, none of which: occurred in a nuclear power plant. This incidence isiconsidered random. based on the over 2 million units shipped starting 1970 and continuing to date. Accordingly, Rosemount believes the Bulletin should reference only Model 1153 B&D and 1154-transmitters and the-references to Model 1151, 1152, and 1153 series A be removed from the bulletin. Page 3 1 --e .--.ye a .-..e

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i Paragraph 2 on page 2 of the bulletin the NRC addresses a broad definition of oil loss. This broad definition of oil loss could include the following mechanisms i - Damage to procons isolation diaphrarms - Corrosion to process isolation diaphragns- - Failure of sensor sealing techniquer; e.g. we3d, branes, etc. l - Failure of fill or evacuation ports i - Internal mechanical sonsor failure o.g. glass to metal seal failure If this broader definition of oil loss is to be considered l all pressure transmitters (of any manufacturer) using a sealed liquid or gas system have the potential for loss (or gain) of fluid which would result in an inaccurate output signal. If this was the issue, a notification for fill fluid loss should not be limited to Rosemount transmitters. Rosemount issued a letter on December 22, 1989 to all U.S. utilities at the suggestion of the NRC (see attachment 1) describing the comprehensive issue of oil loss which would apply to pressure transmitters produced by any-manufacturer. We requested that users report to Rosemount any past, present or future transmitter irregularities with symptoms of oil loss involving all Rosemount origin transmitter 1 equipment. We believe this will be an important factor in supporting our data base on the oil loss isnuo. No t Page 4

ci.. ie "-o t.;i II g~:c wr P.006 Cc9> additional failures have been received as a result of this i letter to dato. i In addition, we have provided substantial and conclusive technical information (Technical Bulletin No. 4 and its references) to show that transmitters which have seen a prescribed operational time at pressure can be considered to be free of the glass to metal seal failure mechanism. This information (Rosemount Technical Bulletin #4 and Engineering Report #D8900115 Rev A) should be used by the utilities in { deselopment of their monitoring program. The NRC draft t bulletin indicates that the information supplied by Rosemount is insufficient. We would like the opportunity to understand and discunn this matter more fully, other changes that Rosemount would suggest are as follows: t 1. On page 1 under "Dfd.?ussion of Safety Significance": The comment on non detectability may have been historically true, but using the proposed diagnostic l guidelines, an incipient failuro can be detected or~ a failed unit will identify itself. Also the phrase "it has been reported" is unclear as to who it was reported to, the NRC, Rosemount, NPDRS system? We suggest the following: 1 Page 5

/ of.cc m M:n rotoern p,ocMos j The performance of a transmitter that is leaking fill-oil gradually deterioratas and may eventually 1 lead to failure. Not until Rosemount published ____ I diagnostic guidelines were falling or failed transmitters generally detectable during operation. Historically some failed transmitters have shown symptoms of loss of fill-oil prior to failure while it was reported that in some cases the failure was l l not detectable during operation. Loss of fill-oil ? r i may result in a transmitter not' peri'orming its intended safety function. 2. on pago 2 - 2nd sentence: e t one cannot " visually" confirm a glans to metal seal e oil loss until a destructive analysis is conducted. However, the proposed diagnostic guidelines I (Rosemount Technical Bulletin #4) can detoct suspect j transmitteru without destructive analysis, i We suggest Rosemount has indicated, to date, that failure of approximately 91 Model 1153 and 1164 transmitters 1 due to loss of fill-oil from a glass to metal seal failure have been confirmed. Since the sensing module is sealed, loss of fill-oil due to glass to metal seal failure cannot be visually confirmed without destructive analysis of the sensing module. l r Page 6 . - ~

. 21. %

• O l,0:.; P M D 'itiT P.00Se00?

I !!owever, non destructive diagnostic procedures (Rosemount Technical Bulletin #4) have been developed to identify suspect fill-all failures.-- - 3. Page 2 - 3rd Sentencot This sentence indicates the NRC has. identified additional " failed" Model 1153 and 1154's with symptoms indicative of oil loss. It is not clear if the NRC has received " failed" units or where'this information comes from. We suggest that the word " failed" bo removed. 4. Pago 2 - Iast Paragraph: 1 We suggest the following terminology: Rosemount has indicated that they manufacture Modal 1151 transmitters and transmitter parts (including sensing modules) for other suppliers. Bailey controls was supplied with Model 1152 sensing modules during the 1982 - 1986 time frame which they-employed in the manufacture of transmitters. The Model 1153 and 1154 have only been supplied under-Rosemount label. 3 Y a Page 7 u +, .~ ~ +

l'

• E.N *% 15 4.4. POSD KUT p,oopoog

] L I I 5. Page 2 - Last Paragraph Last Sentence and First i Sentence on Page 3 1 'i We do not know who this is in referones to and may l be double counting a manufacturer mentioned in the next sentence. Just to repeat, Rosemount has only l A sold nuclear sensing modules, Model 1152, to Bailey, i controls, see #4 above. l

6. Page 3 - Paragraph 2 Bullets under symptoms a leaking transmitter may exhibit We suggest the following to more precisely define

~~ symptoms: The symptoms a Model 1153 or 1154 transmitter may ? exhibit during normal operation if it is leaking fill-oil include: A A sustained drift in the output which can vary o from 0.1% to 24% cumulative drift depending on application specifics, An abrupt decreasing drift in the output of high o range gauge or absolute transmitters, i A change in process noise including amplitude o variations, "one sided noise", or asymmetric. noise distributions. I Page 8

) >tt.N *?o 16:a reaon. p,003.co-l l slow response to or inability to follow planned o i l or unplanned plant transients. i l l The symptoms a Model 1153 or 1154 transmitter may exhibit l during calibration activities if it is leaking fill-oil include: Inability to respond over the entire design o range. i slow response to either an increasing or o decreasing test pressuro. A sustained drift in the zero and span output o which can vary from 0.1% to 24% cumulative drift. i 7. Page 4 - Line 5: Transmitters from suspect lots with sufficient time at pressure and are not drifting should be exonerated from suspicion, not replaced. See Rosemount Technical Bulletin #4 and Engineering Report #D8900115 Rev A. l [ Page 9

"tF..N, 'M :6::7 F0ic a n P.002oc; 8. page 4 - Paragraph 2 - Line 6: i Trending as proposed in Roser.ount Technical Bulletin { $4 will detect oil loss before transmitters fail o "as the failure. occurs" in the esse of high range transmitters. This will provide a means for-l checking for the operational availability of each system with a high degree of confidence.- 9. Page 5 - Paragraph 2 Line 7 I The list of OEM's in Attachment 2 was submitted the NRC on December 18, 1989 as confidential information. This list should not have been disclosed publicly until proper release of the confidentiality agreement had-been secured. l

10. Page 6 - Section 4 last sentonce:

only ranges 8, 9, and 0, of the Models 1153 2 & D and 1154, that have trip points well above their operating pressures should be replaced. Other transmitters from all lots should be monitored the enhan'ced surveillance techniques previously defined (Rosemount Technical Dulletin #4) l until they can be exoneratod. l Page 10 m.w.,-- w-- ,----.w .,r-%- - + - - --

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11. Page.6 - Section Ib:

If additional information is=to be requested you t I should consider the following information to prov de ~~~ j the most comprehensive data base. t 1. s Manufacturer 2. Model number r 3. Transmitter serial number.(sensing modula serial number if it has been replaced) 5. Application description k 6. Installation date 7. Cumulative time in service at pressure (time at zero pressure in standby service does not count as time at pressure) 8. Calibrated pressure range 9. Operating static pressure for differential tranumitters or operating pressure ~for gauge and absolute transmitters 10 Failure symptoms observed P 11. Failure analysis results 12. Corrective actions taken \\ 13. Disposition of a removed transmitter t LI. l' Page 11 ~ ~,...-4 4 .. ~,. - -

i et.% 'N le.: Ir p.~;o or :7 P. ON - E ' -t Rosemount has been a long time reputable supplier to the-nuclear industry. We want to continue to be a respected,_ _ quality supplier. We prefer to meet directly with the NRC l and other interested parties to discuss these comments. We are ready to meet with you at your earliest convenience. Respectfully, & E.l. Vfegk, Stephen J. Wanek Vice President operations ~ cc: Mr. Dennis Allison CRGR i l l l ^ l 1 Page 12 v -~- ,_.r e n-w.-

...,~. < vx re.u i t $d["" " P.005 00 ~~ Va * .,, _ s foi1012) Hi 5600 Tame 4310012 ATTACHMD:T 1 7na tem aresome Decemher 22, 1989 i i t ] I i Tor All U.S. Nuclear Energy racilities transmitter equipmentThis letter regarding certain Rosemount t nuclear energy facilitios.is being distributed to all U.S. e identified as Rosemount Transmitter Models 1151The spec 1154, Rosemount Model 1199 and 1159 remote seals , 1152,-1153,- components of such equipment. and sensor these models is the use of contained fill fluid tThe generic d pressure forces. o transmit BACKGROUNDt in 1969 and approximatelyThe Model 1151 design was first introduce been sold since that time. 2,000,000 such transmitters have widely accepted - due in part to excollont'reliabilitThe tra warranty service frequency of less than ;2% based on sa figures. yrand a es Models 1152, to nuclear service requirements.1153 and 1154.were developed in r 10 CFR 21 notice for 1153 In May 1989, and 1154 models because ofwe issued a unusually high failuro-rates due to' loss o (" oil"). seal failure aggravated by stress imposed by a m t l o-ring. ea The metal o-ring is unique-to Model 1153 series B e a. process and D and all Model 1154 Models 1153 and 1154. implemented in July 1989 and we r Process improvements-were i pments of the loss of fill fluid 10 CFR 21 noticeThese shipments are not cover continued to investigate diagnostic techniques which Rosemount has used to predict incipient failure due to loss of oil a d may be results have been distributed through a series of T Bulletins. n-echnical 6 h "~+e"' e-, m -r

.. + M 05: N. Foia t.w p, g,, cgg j non.. n-, 4 Esem >+aw.e MN %3t.4 ATTACHMENTJ TEE 188088: Two additional issues have come to our attention during the investigation described above. The___ first issue deals with loss of oil not limited to glass to i metal seal problemn or Models 1153 and 1154. 011 may be i lost through failure of any of the containment diaphragm or other seals and may result in false output signals. A similar failure may occur in transmitter designs having a gas filled or an evacuated sealed chamber. Information on Model 1151 transmitters returned by all commercial domestic users for all causes and not limited to warranty life has i been reviewed and we find that approximately.2% of units were returned for problems identified with the oil filled I sensor component. A portion of these returns are due to j loss of fill fluid from all causes including damago and r t corrosion. The Model 1152 is very similar to the Model 1151 and we have only one confirmed report of an oil loss failure t for that model. We believe that all-Model 1152's in service. are in licensed facilities. We further believe that such i oil loss failures of Model 1151 and 1152's in nuclear service is of a random nature. The second issue deals with distributicn of Rosemount sensor modules (the oil contained sensor). Many 1151's and i some 1152'n have been sold commercially under private label agreements. We have also become aware that numerous companies have procured used or surplun Rosemount ) transmitters for resale and sometimes for repair or refurbishment before resale. In some instances these transmitters are resold using the Rosemount name but without our authorization. RBOOMMENDATION: Transmitters made by any manufacturer employing a contained fluid are susceptible to failure due to loss of the containment seal. The designated Rosemount Transmitters are~in this category. We advice that you review the application of all such transmitters in your plant and take the action you deem appropriate to ensure your plant integrity. We recommend that you review our Technical Bulletins referred to above and apply the diagnostic techniqueo described as appropriate, copies of these Technical Bulletins are available on request. These recommendations apply to fluid filled transmitters bearing the Rosemount label and to all other transmitters having sensor components made by Rosemount even though they may carry a different name. We request that i Y l- .i

r ,t ,.- rqt.06.'m le:ir r+;c a n p,oorfoa7 j i nanomew in. ~ m tmwe on,. Emun Prare. We $*M i ATTACIDtENT l' l 1 1. You report to us the use of any transmitter or i component in your plant carrying the Rosemount~Ea'~me'but l which was procured from a refurbisher/remanufacturer. I 2. You report to us all failures of Rosemount origin transmitter equipment that you suspect may have been cae to a loss of fill fluid. We are asking for information on past, present and future events. please retain any such suspected failed units and its data so we may perform an analysis of the failure. l Flease communicate your information and inquiries to: f l Mark Van Sloun I Rosemount Inc. Mail Station BS 12001 Technology Drive Eden Prairie, MN 55344 phone (612) 828-3484 i Rosemount remains committed to providing quality products and services to the nuclear power industry. We appreciate l your cooperation on this matter and look forward to meeting l your future needs. l Sincerely, ROSEMOUNT INC. k E7is [q .8Alphw f W.tev,]z, Stephen J. Wanek Vice president, operations j l C -~w-sm., ? i . - ~ - e-e

o' o , to the Minutes of CRGR Meeting No. 179 Proposed Generic Letter on BWR Channel Box Bow Problem February 7, 1990 t TOPIC A. Thadani (NRR) atd D. Fieno (NRR) presented for CRGR review a proposed generic letter on actions to be taken by BWR licensees to address the problem of loss of thermal margin due to excessive fuel channel box bow. Briefing slides used by the staff to guide their presentation and discussion with the Committee at this meeting are enclosed (see Attachment). BACKGROUND The documents submitted to CRGR for review in this matter were transmitted by memorandum dated January 10, 1990, J.H. Sniezek to E.L. Jordan; that review package included the following documents: 1. Proposed Generic Letter (undated), " Correction of Deficiency in BWR Critical Power Ratio Calculation Due To Channel Box Bow", and attachnent: a. NRC Information Notice 89-69, dated September 29, 1989, " Loss of Thermal Margin Cuased by Channel Box Bow" 2. " Response to Requirements for Content of Package Submitted for CRGR Review" CONCLUSIONS / RECOMMENDATIONS As a result of their review of this matter, including the discussions with the staff at this meeting, CRGR recommended in favor of the issuance of guidance to BWR licensees in connection with the channel box bow problem; but the Com-mittee recommended a number of changes, with respect to both the format and the content of the guidance to be issued, as follows: 1. The vehicle for implementing this regulatory action should be an NRC Bulletin instead of a Generic Letter; reference to 10 CFR 50.54(f) should be deleted from the bulletin. The bulletin can be addressed to CP holders (for their information); but no " Actions" or " Reporting Requirements" should be directed to CP holders at this time. 2. The scope of " Requested Actions" should be narrowed to apply only to BWR licensees that currently use channel boxes for a second bundle lifetime; the only action requested of such licensees should be to verify that current technical specifciation CPR limits are met. 3. The scope of " Reporting Requirements" should be similarly narrowed to apply only BWR licensees that currently use channel boxes for a second I bundle lifetime; affected licensees' responses shall include the following:

.g. a. Advise the NRC of the number and disposition of such channel boxes in the core, b. Describe the methods and the associated data base used to account of channel box bow during their second bundle lifetime use, to conformance with the CPR technical specification operating and safety limits. 4. The staff acknowledges that the possibility of any fuel failures as a result of channel box bow in the first bundle life time is remote for U.S. BWRS; so ne " Actions" or Reporting Requirements" should be directed to BWR licensees in those circumstances. The discussion regarding new vendor methodologies (currently under review by NRC), that properly account for channel box bow for first bundle lifetime, does apply to all BWR licensees, and should be retained in the bulletin. The. staff should also indicate in that discussion when the NRC review will be completed and the new methodologies approved for use by the licensees in core reload calculations, and how the channel box bow question will be handled in core reload applications in the interim. 5. The staff should coordinate all changes resulting from CRGR recommend-- ations with the CRGR staff, and resubmit a revised package to the CRGR for final review on a negative consent basis. It was noted that this action was considered to be justified as a compliance backfit. l

c7y rtf h 7 9 ch...,teqth f t ? . PRESENTATION TO~CRGR ON PROPOSED GENERIC LETTER ON DEFICIENCY IN BWR THERMAL LIMITS CALCULATIONS CAUSED BY CHANNEL P0X BOW FEBRUARY 7, 1990 P A tta c h m e n t to Enclo su v c I

1 BACKGROUND o ISSUE DISCUSSED WITH NRC BY ABB ATOM, INC. (ADB) AT MEETING ON JULY 20, 1989 ON OSKARSHAMN 2 FUEL FAILURES OBSERVED DURING AUGUST 1988 REFUELING OUTAGE -o MEETINGS WITH US BWR FUEL VENDORS GE SEPTEMBER 12, 1989 l ANF SEPTEMBER 13, 1989 l o NRC INFORMATION NOTICE 89-69 (SEPTEMBER 29, 1989) l

2 OSKARSHAMN 2 FUEL FAILURE CONCERNS o EXTENSIVE INVESTIGATIONS LED TO THE CONCLUSION THAT THE FUEL FAILURES WERE CAUSED BY DRYOUT (CLADDING 0VERHEATING) CONDITIONS WITH SECONDARY FAILURES CAUSED BY HYDRIDING o DRYOUT CONDITIOP ON FAILED RODS CAUSED BY TWO EFFECTS CHANNEL BOX B0W GREATER THAN EXPECTED INCORRECT MODELLING-IN PROCESS COMPUTER OF SVEA-64 FUEL BUNDLES (THIS IS NOT A CONCERN FOR US BWPs)

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e ta S ,a 1 l j IN 89-69 i September 29, 1989 " " 2 "'2 Figure 1 i Channel Bow 1 l C C -- EFFECT OF CHANNEL BOWING ONCE-BURNED FUEL l FOOOOOOOO' r ,e r O0000000 6 00000000 i j OOOO0000 i FRESH FUEL a OOOO0000 j 00000000 i Failed Fgel Rod ?j o0000000 2 tOOOOOOOO; O [ ] J L CONTROL e ROD a nm... i; er, m.,,.,, n. a,. _., n v % L ( l q 3 FRESH FUEL

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e < 5 APPLICABLE REGULATIONS o GENERAL DESIGN CRITERION 10 ^ THE REACTOR CORE AND.... SHALL BE DESIGNED WITH APPROPRIATE MARGIN TO ASSURE THAT SPECIFIED ACCEPTABLE FUEL DESIGN LIMITS ARE NOT EXCEEDED DURING ANY CONDITION OF NORMAL OPERATION,,,,, o 20 CFR 50,36(c)(1)(1)A RE0ll!RES SAFETY LIMITS TO'BE SET FOR IMPORTANT PROCESS VARIABLES WHICH ARE FOUND TO BE NECESSARY TO REASONABLY PROTECT THE INTEGRITY OF THE PHYSICAL BARRIERS THAT GUARD AGAINST THE UNCONTROLLED RELEASE OF RADI0 ACTIVITY l l l i

i ,y 6 IMPACT OF BWR CHANNEL BOX BOW o POTENTIAL VIOLATION OF THE SAFETY LIMIT MINIMUM CRITICAL POWER RATIO (SLMCPR) AND POTENTIAL FOR FUEL FAILURES IN BWRs o IMPACT ON LINEAR HEAT GENERATION RATE (LHGR) AND FUEL PELLET OVERHEATING o IMPACT ON TRAVERSING INCORE PROBE (TIP) READINGS AND EFFECT ON CORE MONITORING a i r

~ 7 IMPACT OF CilANNEL B0W ON CPR MARGINS o GE D-LATTICE PLANTS DELTA-CPR/ICPR UP TO 03 C-LATTICE PLANTS DELTA-CPR/ICPR UP TO 02 ABOVE ESTIMATES ARE FOR SINGLE BUNDLE LIFETIME CHAPNELS: IMPACT IS MUCH GREATER F0P SECOND BilNDLE LIFETIME CPANPELS Dl1E TO ACCELERATED RATE OF BOW o ANF PRELIMINARY RESULTS COMPARABLE TO GE RESULTS FOR NEW CORE ANALYSIS METHODS CORES ANALYZED BY CllRPENTLY APPROVED METHODS CONTAIN SUFFICIENT CONSERVATISM TO ACCOUNT FOR CHANNEL B0W 1 EFFECTS

g *i,, 4 8 IMPACT OF' CHANNEL BOW ON LHGR MARGINS-IMPACT LESS IN BOTTOM 0F CORE WHERE MARGIN T0 LHGR IS LEAST~ IMPACT GREATER IN TOP 0F CORE WHERE MARGIN TO LHGR IS GRF.ATEP OVERALL IMPACT ON LHGR NOT JtIDGED TO BE SIGNIFICANT-i

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.-l . q q =; IMPACT OF CHANNEL BOW ON TIP-READINGS l !a

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.h NEGLIGIBLE-lMPACT ON GAMMA - TIPS IMPACT ON THERMAL-TIPS - HOWEVER UNCERTAINTY USED IS LARGE-ENOUGH-T0 COVER ANY INCREASE. LIP TIP llNCERTAINTY L ol' .q e l. l~ b_.

a <,., 10 CORRECTIVE ACTIONS REQUESTED BY PROPOSED GENERIC LETTER o ENSURING THAT THE PROCEDURES FOR MONITORING THERMAL LIMITS DURING REACTOR OPERATION WILL PREVENT VIOLATION OF THE MINIMUM CPR OPERATING LIMIT BY THE USE OF AN NRC APPROVED METHODOLOGY THAT TAKES INTO ACCOUNT THE NEW DATA DN FUEL CHANNEL B0 WING, OR o IMPOSIMG ON THE OPERATING CPR LIMIT (OR LIMITING CURVE) A CHANNEL B0W PENALTY OF EITHER 0.03 DELTA-CPR FOR D-LATTICE PLANTS OP 0,02 DELTA-CPR FOR C-LATTICE (0R S-LATTICE) PLANTS AND BY REMO\\'ING ANY CHANNEL B0XES THAT ARE BEING REUSED AFTER THEIR FIRST BUNDLE LIFETIME l

E i.,..... 11' PESPONSE REQUESTED BY-PROPOSED-GEPERIC LETTER o WHETHER UTILITY WILL IMPLEMENT THE CORRECTIVE ACTIONS-FOR THE FIRST RELOAD SCHEDULED AFTER APRIL'30, 1990, INCLUDING THE DATE OF THE RELOAD o WHETHER OR NOT CHANNEL. BOXES ARE BEING USED FOR A SECOND BUNDLE LIFETIME 4. ~~

w . ' ",f.. _ 12 JUSTIFICATION FOR CONTINUED OPERATION r o CONSERVATISM IN SAFETY LIMIT CPR o LOW PROBABILITY OF EXCEEDING THE SAFETY LIMIT CPR DURING j TIME FOR IMPLEMENTING CORRECTIVE ACTION (LOW PROBABILITY OF HAVING LIMITING TRANSIENT) I o LOW PROBABILITY OF A R0D G0ING INTO B0ILING TRANSITION IF THE SAFETY LIMIT CPR IS EXCEEDED P o LOW PROBABILITY THAT ANY SUCH R0D WILL BE IN BOILING TRANSITION FOR A SIGNIFICANT PERIOD OF TIME l r r ?}}