ML20247D230
| ML20247D230 | |
| Person / Time | |
|---|---|
| Issue date: | 05/05/1989 |
| From: | Rossi C Office of Nuclear Reactor Regulation |
| To: | Bernardini A LITTON SYSTEMS, INC. |
| References | |
| REF-QA-99900401 IEIN-89-023, IEIN-89-23, NUDOCS 8905250255 | |
| Download: ML20247D230 (6) | |
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UNITED STATES
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lj WASHINGTON, D. C. 20S$5 May 5, 1989
-l Mr. A. J. Bernardini, President Veam Division Litton Systems, Inc.
100 New Wood Road Watertown, Connecticut 06795-3339
Dear Mr. Bernardini:
Thank you for your letter of March 31, 1989, concerning NRC Information Notice
-(IN) 89-23, " Environmental Qualification of Litton-Veam CIR Series Electrical 1
Connectors," dated March 3, 1989. We regret that you feel IN 89-23 casts doubt on all possible applications of CIR series connectors.
In fact, IN 89-23 clearly addresses environmental qualification (EQ) for LOCA conditions; it does not address non-safety applications or locations outside the reactor containment.
The vast majority of environmentally qualified applications of CIR series connections that have come to our attention involve licensees who rely on CombustionEngineering,Inc.(CE)forqualificationsupport;specifically, 39 of 42 plant applications with which we are familiar involve CE-supplied instrument systems. These applications represent over one-third of the commercial nuclear power reactors in the country. This sample provides more j
than adequate basis to alert all licensees to a potential generic problem.
]
We cannot, as you request, provide you with a copy of the CE test report 1
because the report is proprietary.
It has been freely made available to us for review during inspections of CE and licensets. Yeur request for a copy l
of the report should be directed to CE.
i Your letter states that you "have always certified" your products to a maximum radiation dose of 150 Mrad. Environmental qualification requirements of Section 50.49 of Title 10 of the Code of Federal Regulations are not based on certification of a radiation resistance level, bvt rather on application-
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specific analyses supplementing type test reports.
IEEE Standard 323-1974 has long been the nuclear industry guideline for suggested generic test conditions.
For a Loss of Coolant Accident (LOCA) in Pressurized Water Reactors, IEEE 323-1974, Appendix A, suggests 150 NRad as a typical accident dose, Comonly 4
50 Mrad is added for a normal oparation dose, and a 10 percent margin as j
prescribed by IEEE 323-1974, giving a total dose for generic tests of about j
220 Mrad. The CE testing was reported to be consistent with this dose. The CE I
j test dose was (1) consistent with typical LOCA qualification test doses in the j
1 industry and (2) the dose actually used by one-third of the operating plants l-for qualification purposes. Your letter also states that IN 89-23 makes no 1
yl mention of the use of Grafoil seals or why CE developed their " clamp" remedy.
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Mr. A. J. Bernardini May 5, 1989 IN 89-23 references NRC Inspection Report No. 99900401/88-01, dated January 10, 1989, which is available in all NRC Public Document Rooms and is enclosed for your information.
The inspection report discusses CE's testing and development
. of remedies for their test failures in detail.
IN 89-23 specifically describes why remedies were developed by CE.
We trust that this letter resolves your concerns.
Please do not hesitate to contact us if you have further concerns in this matter or wish to bring additional information to our attention.
Sincerely, Onginal mgned by Charles E. Rossi Charles E. Rossi, Director Division of Operational Events Assessment Office of Nuclear Reactor Regulation
Enclosure:
Combustion Engineering Inspection Report No. 99900401/88-01 DISTRIBUTION (Central Files ?
PDR VIB' Reading' DRIS Reading TMurley JSniezek FMiraglia BGrimes EWBrach UPotapovs RWilson CERossi CBerlinger (LETTER TO MR. BERNARDINI)
- Previously concurred.
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- CBerlinger DATE :04/25/89
- 04/25/89
- 04/26/89
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Mr.- A. J. Bernardini May 5, 1989 IN 89-23 references NRC Inspection Report No. 99900401/88-01, dated January 10, 1989, which is available in all NRC Public Document Rooms and is enclosed for your information. The inspection report discusses CE's testing and development of remedies for their test failures in detail.
IN 89-23 specifically describes why remedies were developed by CE.
We trust that this letter resolves your concerns.
Please do not hesitate to contact us if you have.further concerns in this matter or wish to bring additional information to our attention.
Sincerely, Original Signed by Charles E. Rossi Charles E. Rossi, Director Division of Operational Events Assessment Office of Nuclear Reactor Regulation
Enclosure:
Combustion Engineering Inspection Report No. 99900401/88-01 DISTRIBUTION d Central Files!
PDR VIB Reading DRIS Reading TMurley JSniezek FMiraglia BGrimes EWBrach UPotapovs RWilson CERossi CBerlinger l
(LETTER TO MR. BERNARDINI)
- Previously concurred.
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- BC:GCB:NRR :DOEA:NRR NAME :RWilson:jh*
- UPotapovs*
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- BGrimes*
- CBerlinger DATE :04/25/89
- 04/25/89
- 04/26/89
- 04/26/89
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Mr. A. J. Bernardini.
IN 89-23 references NRC. Inspection Report No. 99900401/88-01, dat'ed January 10, 1989, which is available'in all NRC.Public Document Rooms and is enclosed for your information. The inspection report discusses CE's testing and development of remedies for their test failures in detail. ilN'89-23~specifically describes why remedies were developed.by CE.
We trust that this letter resolves your concerns. Please do not hesitate to contact us-if you-have further concerns in this matter or wish to bring additional information to our attention.
Sincerely, Charles E. Rossi, Director Division of Operation Events Assessment Office of Nuclear Reactor Regulation
Enclosure:
" Combustion Engineering Inspection Report N';.. 99900401/88-01 DISTRIBUTION
' Central Filess PDR VIB Reading DRIS. Reading TMurley JSniezek FMiraglia BGrimes EWBrach UPotapovs RWilson i
l (LETTER TO MR. BERNARDINI)
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Your letter also states that IN 89-23 es no mention of the use of Grafoil seals Q why CE developed their "cla
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IN 89-23 references NRC Inspection Report No. 9990040/88-01, dated January 10, 1989, which is available in all NRt\\Public Document Rooms [ The inspection report discusses CE's' testing -
and development of remedies for their test failures in detail.- IN 89-23 specifically ' describes why remedies were developed by CE.
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We trust that thiksletter resolves your concerns.
Please do not,h'esitate to contact us if you have further concerns in this matter or wish,to bring additional information sto our attention.
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L Your 1etter also states that IN.89-23 makes no mention of the se of Grafoil seals or why CE developed their " clamp" remedy.
IN 89-23 ref ences NRC Inspection Report No. 9990040/88 01,. dated January 10, 1989, hich is available in all NRC Public Document Rooms. The inspection report discusses CE's testing and development of remedies for their test failures in detail.
IN 89 23 i
specifically d cribes why remedies were developed by CE We trust that th s letter resolves your concerns.
Please do not hesitate to contact us if you'tave further concerns in this matte ver wish to bring additional information to our attention.
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.~'f NUCLEAR REQULATORY COMMISSION, 7,e,x g
WASMHWOTON. D. C. 30586 l t.
JAN 161989 1j u
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i Docket No. ' 99900401/88-01'
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Mr. Walter D. Mawhinney, Vice President j
Nuclear Quality Systems i
Combustion Engineering,-.Inc.
Power Systems Group 1000 Prospect-Hill Road Windsor, Connecticut 06095
Dear Mr. Mawhinney:
' This letter addresses the inspection of your facility at Windsor, Connecticut :
conducted by Mr. Richard C. Wilson of this office on November 8-10, 1988, and the discussions of his findings with Mr. J. J. Holloway and members of your-staff.at the conclusion of the inspection.
The inspection was conducted-as a result of an allegation concerning moisture effects on the environmental qualification of Litton-Veam electrical connectors used in1 Core Exit Thermocouple and Reactor Vessel Level Monitoring Systems supplied by Combustion Engineering. Areas examined during the NRC inspection
. and our findings' are discussed in the enclosed report. This inspection con-sisted of an examination of procedures and representative records, interviews with personnel, and observations by the inspector.
Within the scope of this inspection, we found no instance where you failed to meet NRC requirements. However, documentation reviewed during this inspection clearly does not establish LOCA qualification of unclamped Litton-Yeam connectors for any application other than vtry low voltage thermocouple circuits. Further, the connector behavior during the LOCA tests indicates 1 unsuitability for any other use requiring LOCA qualification.
In accordance with 10 CFR 2.790 of the Commission's regulations, a copy of this letter and the enclosed inspection report will be placed in the NRC's Public Document Room.
If this report contains an information thet you believe to be exempt from disclosure under 10 CFR 9.5(a)y(4), yon must (a) notify this office by telephone within 10 days from the date of this letter of your intention to file a request for withholding and.(b)' submit within 25 days from the date of this letter a written. application to this office to withhold such information.
If your receipt of this letter has been delayed so that you have less than three days for your review, please notify this office promp(b)y(1), any tl so that a new due date may be established. Consistent with 10 CFR 2.790 1
application for withholding must be accompanied by an affidavit executed by the owner of the-information that identifies the document or part sought to be withheld and that contains a full statement of the reasons which,are basis for ENCLOSURE Nd IOb
JAN 161989 Mr. Walter D. Mawhinney 2
the claim that the information should be withheld from public disclosure.
10 CFR 2.790(b)(1) further requires that the statement specifically address the considerations listed in 10 CFR 2.790(b)(4). The information sought to be withheld shall be incorporated as far as possible into a separate part of the affidavit.
If we do not hear from you in this regard within the specified periods noted above, the enclosed report will be placed in the Public Document Room without changes.
Should you have any questions concerning this inspection we will be pleased to discuss them with you.
Sincerely, Original signed by E. Williarn Brach E. William Brach, Chief Vendor Inspection Branch Division of Reactor Inspection and Safeguards Office of Nuclear Reactor Regulation
Enclosure:
Appendix A. Inspection Report 99900401/88-01 DISTRIBUTION RIDS Code IE:09 VIB Reading DRIS Reading BGrimes EBrach UPotapovs RWilson(2)
JCraig
- SEE PREVIOUS CONCURRENCE PAGE.
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NAME :RCWilson:mkm*
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DATE :01/03/89
- 01/04/89
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ORGANIZATION: COMBUSTION ENGINEERING, INC.
POWER SYSTEMS GROUP WINDSOR, CONNECTICUT REPORT INSPECTION INSPECTION NO.:*99900401/88-01 DATE:
11/8-10/88 ON-SITE HOURS:
16 CORRESPONDENCE ADDRESS: Mr. Walter D. Mawhinney, Vice President Nuclear Quality Systems Combustion Engineering Inc.
Power Systems Group 1000 Prospect Hill Road Windsor, Connecticut 06095 ORGANIZATIONAL CONTACT: Mr. Thomas R. Swift, Manager, Nuclear Quality Systems TELEPHONE NUMBER:
(203) 285-9204 NUCLEAR INDUSTRY ACTIVITY: CE has had NSSS contracts for 16 domestic reactors, and has support service contracts for approximately 40 reactors worldwide. -
ASSIGNED INSPECTOR: [@f[h t/3 R. C. Wilson, Engineer, Special Projects ate Inspection Section OTHERINSPECTOR(S):
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Uldis Potapovs. Chief, Specfpl Projects Inspection Date Section, Vendor Inspection Branch, DRIS, NRR INEPECTION BASES AND SCOPE:
A.
BASES:
10 CFR Parts 21 and 50 B.
SCOPE: This inspection was made as a result of an allegation concernirg moisture effects on the environmental qualification of Litton-Veam elec-trical connectors used in Core Exit Thermocouple (CET) systems and Reactor.VesselLevelMonitoring(RVLM)systemssuppliedbyCombustion Engineering.
I PLANT SITE APPLICABILITY: Numerous; see Section E.4 and Table I at end of report.
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' ORGANIZATION:. COMBUSTION ENGINEERING, INC.
POWER SYSTEMS GROUP
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WINDSOR. CONNECTICUT 1
REPORT INSPECTION NO.:.99900401/88-01 RESULTS:
PAGE 2 of 10 A.
VIOLATIONS:
None
)
B.
NONCONFORMANCES:
None C.
UNRESOLVED ITEMS:
None j
D.
STATUS OF PREVIOUS INSPECTION FINDINGS:
None are applicable to the scope of this inspection; none were addressed during this inspection.
.i l
E.
INSPECTION FINDINGS AND OTHER COMMENTS:
1.
Allegation scope The allegation consists of two specific concerns, both relating to multi-pin electrical connectors supplied by CE as portions of instrumentation systems required to be environmentally qualified to 10 CFR 50.49. The concerns are as follows:
a.
It was alleged that Core Exit Thermocouple systems are subject to signal errors larger than reported by CE based on qualifi-cation test report CE NPSD-230-P. Qualification can only be accomplished by a retrofitted improvement for the original connectors or use of an improved connector, either of which prevents moisture ingress into the connector.
b.
It was alleged that Reactor Vessel Level Monitoring systems supplied by CE and using the Heated Junction Thermocouple (HJTC) principle require periodic testing to maintain qualifi-cation because an undersized connector gasket can permit moisture ingress.
Undersized gaskets may have been manufac-tured undersized or may have been compressed during service.
These two concerns were conveyed to CE and were addressed during this inspection.
l
ORGANIZATION: COMBUSTION ENGINEERING, INC.
' POWER SYSTEMS GROUP
~
WINDSOR.-CONNECTICUT REPORT INSPECTION NO.: 99900401/88-01 RESULTS:
PAGE 3 of 10 2.
Core Exit Thermocouple System The CE Core Exit Thermocouple (CET) system is intended to satisfy Regulatory Guide 1.97, and must be environmentally qualified for Loss of Coolant Accidents (LOCAs) and other accidents. The area of concern is a connector that electrically and mechanically joins two multi-conductor, mineral-insulated, metal-jacketed cables, one from the core exit thermocouple and the other to the containment electrical penetration assemblies. The connector is exposed to the containment atmosphere.
CE's original CET connector. environmental qualification is based on qualification report CE NPSD-230-P, " Class 1E Qualification of the Core Exit' Thermocouple - Mineral Insulated Cables," April 1983 (Proprietary).
It covers testing of 8-pin size 20 connectors in the CIR series manufactured by Veam Division of Litton Systems, Inc.
used with cable manufactured by Electronic Resources Division Inc.
of Whittaker Corp. Size 16 connectors are similar. This report had been reviewed previously during EQ inspections of licensees, and it was reviewed again during this inspection.
Report CE NPSD-230-P documents moisture ingress into the connectors tested. Post-test inspection is reported showing that the face seal gasket was completely degraded, and that the elastomeric inserts used to support pins and sockets were covered with a flaky gray material produced by interaction of the elastomer with borated water which "had obviously leaked into the connector."
A variety of anomalous behaviors occurred during the LOCA test.
In evaluating them the inspector reviewcd the detailed test report TR-ESE-495 (Proprietary) dated January 7,1983 and original strip chart recordings of the thermocouple signals. Of particular con-cern was the impact of periodic cable insulation resistance measure-ments at 50 vde, which appeared to charge the cables and cause spurious signal spikes for as long as an hour after voltage appli-cation. These tests also decalibrated the recorder amplifiers; the recorder was in fact replaced with a different type midway through 4
the 30-day LOCA test. Thermocouple showed different time responses to temperature changes because of varying thermal masses and junc-i.
tion types (grounded and ungrounded); when intervals between actual temperature' changes were rather small, the slowest response thermocouple signal deviated considerably from others because of obvious time lags. The temperature cycling was reduced by more closely controlling the temperature in the reference oven.
i L __. _ __ __
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' ORGANIZATION: COMBUSTION ENGINEERING. INC.
-POWER. SYSTEMS GROUP WINDSOR. CONN MTICUT REPORT INSPECTION NO.: 9990-0401/88-01 RESULTS:
PAGE 4 of 10 Anomalies were processed for these abnormalities as required by test procedure 00000-ESE-391 Rev. 01 (Proprietary) dated 1
September 1, 1982.
In particular Notice of Anomaly No. 2 j
dated October 14, 1982 states the following reason for apparent 5
thermocouple signal errors greater than the 122'F allowed by the test procedure (of the order of 45'F):
j "It is proposed that Meger (sic) testing prior to initiating transients created a capacitor. Wher: the specimen was exposed to a steam environment the Litton connector leaked and humidity or wetting of the pins created leakage paths for stored charge."
Qualification report CE NPSD-230-P also discussed this anomaly, concluding that the temporary perturbation of the thermocouple signals caused by insulation resistance checks should not be considered in the evaluation of CET system performance. Strip chart excerpts demonstrating the transient behavior are included in CE NPS0-230-P. Bench tests with line resistances simulating 180-190 foot Chrome 1/Alumel cables and a simulated 1000 ohms connector resistance further showed acceptable performance.
Qualification report CE NPSD-230-P and its supporting documenta-tion thus convey the following representations concerning LOCA qualification of the Litton-Veam connectors in the CET system.
The connectors are environmentally qualified for an overall system accuracy of 122'F; the connectors experienced moisture ingress and disintegration of the face seal gasket; and tran-sient spikes as large as 45*F had been evaluated as a test anomaly.
This report was issued in April 1983.
The attention of the CE engineers then apparently focused on the Reactor Vessel Level Monitoring (RVLM) system addressed in Section E.3 of this inspection report. The RVLM system feeds heater current through the connectors, so the low insulation resis-tance of a moisture filled connector was recognized as unacceptable.
CE then proceeded with activities intended to develop a " dry" connector for RVLM use, as described in Section E.3 below.
In October 1985 CE formed a small task force to investigate the possibility that moisture ingress into the CET connectors could generate a " battery effect," such that the LOCA test 45'F spikes
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ORGANIZATION: COMBUSTION ENGINEERING, INC.
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. POWER SYSTEMS GROUP WINnRnD r_nNNrrT f rilT REPORT INSPECTION NO.: 99900'401/88-01 RESULTS:
PAGE 5 of 10-t may have been real rather than anomalous performance. -The task force was unable to rule out the possibility of a battery effect, and in December 1985 recommended exploratory testing. Such testing was performed late in 1986 as reported in NPSD-230-P Supplement 1 (Proprieu y), undated but distributed to customers by letters dated May 11, 1987. A summary of the testing was also transmitted to the NRC sy letter dated May 22, 1987.
In the " battery effect test" conn 2ctors in thernmouple circuits were thoroughly wetted.
The signal emfs from the thermocouple in a 400*F oven were contin-uously monitored while the connectors' were dried in a 200'F oven, so that the effects of varying amounts of moisture down to and including a very thin film could be observed. To maximize errors, a long run of cable was coiled in the oven (1000 ohms resistance from thermocouple to connector).
The supplemental test showed that moisture ingress into the Litton-Veam connector can produce spurious signal spikes of 45'F in the CET system, as had been observed in the 1982 testing but attributed to anomalies. The May 1987 letters cited in the previous paragraph provided analyses to show the acceptability of this error in CET systems. Another CE letter issued during this inspection November 9, 1988 - provides additional data analysis to show that in fact the originally claimed 122*F is indeed valid.
-The inspector reviewed all of this material and found it to be satisfactory subject to ongoing review of the NRC Plant Systems Branch to address (1) the acceptability of the quoted t45'F error and (2) the basis for subsequently reducing the error to 222*F.
The inspector concludes that CE's activities with respect to the CET portion of the allegation appear adequate.
3.
Reactor Vessel Level Monitoring System The CE Reactor Vessel Level Monitoring (RVLM) system uses a combina-tion of normal and Heated Junction Thermocouple (HJTCs) to monitor vessel level, on the premise that an HJTC will be cooler if sur-rounded by water than by steam. As noted above, moisture ingress into HJTC connectors is unacceptable because of the heater current transmitted through the connectors.
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POWER SYSTEMS GROUP WfNDSOR. CONNFTICUT l
REPORT INSPECTION NO.: 99900401/88-01 RESULTS:
PAGE 6 of 10 CE developed two alternatives to the Litton-Veam connector for RVLM use. Each uses an inorganic Grafoil gasket ir, place of the Litton-Veam gasket. Grafoil is a graphite gasket material manufac-tured by Union Carbide Corporation.
One of the alternatives is a connector supplied by the CET and RVLM cable manufacturer. Electronic Resources Division Inc. of Whittaker Corporation. This is a conventional type threaded connector that applies a positive loading force to the Grafoil gasket. The inspector reviewed the qualification documentation for this connector, including report CE NPSD-275-P "Sununary Report:
Class 1E Qualification Test of the Electronic Resources Division (ERD) Electrical Connectors and Mineral Insulated Cable" dated November 1984 (Proprietary). The test specimens were models 16-26-00200-2 and -4.
Both CET and RVLM applications were addressed. The documentation was found satisfactory. With respect to gasket compression by repeated connects / disconnects, the test specimens were subjected to ten mechanical cycles.
One test specimen admitted water during the LOCA test.~ This deviation was addressed in the qualification report and in NTS Hartwood Fonnal Report No. 558-1572, " Nuclear Qualification Testing of Class IE ERI Mineral Insulated Cable and Connector Assemblies" dated October 31,1984(Proprietary)whichwas selectively. reviewed by the inspector. Change of Procedure No. 6 and Notice of Deviation No. 8, both contained in Appendix B of the test report, document that the leaking connector had been found loosely mated during incoming inspection after the gamma irradi-ation test preceding the LOCA test, and was retorqued. Since the other test specimens did not leak during the 30-day LOCA test or a subsequent 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> submergence test, it was assumed that the leakage was caused by shipping or handling damage to or from the irradiation test.
It appears reasonable to assume type qualifi-cation for ten cycles aging..
The other alternative developed by CE consists of modifying the Litton-Veam connector to (1) replace the elastomeric gasket with a Grafoil gasket and (2) add provisions for loading the Grefoil gasket with a threaded arrangement that is tightened on the connector plug after the bayonet joint between plug and receptacle is engaged.
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1 ORGANIZATION:. COMBUSTION ENGINEERING, INC.
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POWER SYSTEMS GROUP WINDSOR. CONNECTICUT REPORT INSPECTION NO.: 99900401/88-01 RESULTS:
PAGE 7 of 10 i
The connector is seal-welded to the metal-sheathed cable in order to keep its mineral insulation dry. The retrofit modification was designed to be added to existing cables with integral Litton-Veam connectors, whereas the ERD connector could only be used for new manufacture. Environmental qualification of the retrofit was based on the ERD connector qualification testing supplemented by analysis addressing differences in the two designs.
The CE qualification report for the retrofit is CE NPSD-296-P,
" Qualification Summary Report for the Grafuil Gasket Retrofit for Litton Connectors," May 1985 (Proprietary). This report supplements the'RDE connector qualification report by providing descriptions and analyses.of differences in the two designs and by describing several tests performed on the retrofit design. LOCA was addressed by analysis of torques, densities, seal pressures, and the like.
Radiation and thermal aging were also addressed by analysis. Tests addressed mechanical cycling (Grafoil gasket and Belleville spring),
thermal cycling,. vibration aging, and seismic. One of th'e four test specimens had received radiation and temperature aging. The inspector concluded that qualification of the retrofit cesign is based on a reasonable combination of test and analysis as allowed by 10 CFR 50.49 paragraph (f)(2).
The RVLM portion of the allegation deals with the retrofit modifi-cation of the Litton-Veam connector.
If the Grafoil gasket is too thin, the clamping device may simply achieve a metal-to-metal bottoming instead of loading the gasket. A possible method of assuring that the gasket is thick enough is to ensure that the travel of the threaded clamp before bottoming is less with the plug mated to its receptacle than with the unmated plug. In this regard the inspector questioned CE personnel and also reviewed installation instruction 0000-CCE-GL80-14, Revision 02, " Guidelines for Litton Connector Grafoil Gasket Retrofit," dated November 11, 1980.
CE stated that control of gasket dimensions and density assure proper fit.
In addition, step 8.1.3. of the installation instruc-tions, which addresses the bayonet action of joining the plug and receptacle, states " Observe a tactile click as the coupling nut rotates past cams." The tactile click occurs when the grafoil gasket partially relieves compression'as the bayonet coupling action is completed.
Finally, if the gasket is loaded a gap is-evident between the clamp locking sleeve and coupling sleeve (thetwolarge,externalpiecesoftheclamp).
....-...-.e
4 ORGANIZATION:. COMBUSTION ENGINEERING, INC.
POWER SYSTEMS GROUP utwneno enwwrrTienT REPORT INSPECTION NO.: 99900401/88-01 RESULTS:
PAGE 8 of 10 Although the gap is not mentioned in the installation instruction, it is shown in Figure 1 of the instruction. With respect to comp-ression of the gasket during use, the type qualification limit of ten disconnect cycles and the information described above appear adequate. However, modification of the installation sanual to address the gap to specify a minimum dimension, and to alert plant maintenance personnel to address the tactile click and minimum gap each time a connector is reconnected, would appear to be reasonable enhancements.
The inspector concludes that CE's activities with respect to the RVLM portion of the allegation appear reasonable. Adequate qualifi-cation basis appears to exist for both the retrofit and ERD con-nector designs. The retrofit installation instructions also appear to be adequate to ensure Grafoil gasket loading, although they could be enhanced as noted in the previoet paragraph.
I The inspector noted that various other designs had been considered prior to CE's decision to proceed with the selected retrofit designed. These were not reviewed since only the retrofit design considered was supplied to customers and claimed to be environ-mentally qualified. Comparison of alternate designs was outside the scope of the inspection except for the similarity argument described above in qualification of the retrofit design.
4.
Conclusions Both parts of the allegations clearly address legitimate technical concerns. The inspector concludes that in each case CE has acted in a reasonable manner and has adequately addressed the area of concern.
No violation or nonconformances were identified, either directly related to the allegation or in other inspected areas.
Table I of this inspection report shows the domestic plants using Combustion Engineering CET or RVLM systems, together with the type of connector believed used in each case.
The following plants are also known to have used Litton-Yeam connectors in applications other than CE-supplied CET or RVLM systems:
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ORGANIZATION: COMBUSTION ENGINEERING. INC.
POWER SYSTEMS GROUP WINDSOR. CONNECTICUT REPORT.
INSPECTION N0.: 99900401/88-01 RESULTS:
PAGE 9 of 10 Plant Docket No.
Litton-Veam Connector Usage Haddam Neck 50-213 head vent solenoid valves i
Main Yankee 50-309 non-CE CET system Millstone 3 50-423 transmitter seals, other Documentation reviewed during this inspection clearly does not establish LOCA qualification of unclamped Litton-yeam connectors for any application other than very low voltage thermocouple circuits. Further, the connector behavior during the LOCA tests indicates unsuitability for any other use requiring LOCA qualification.
F.
PERSONS CONTACTED:
W. D. Mawhinney, Vice President, Nuclear Quality Systems
- J. J. Holloway, Vice President, Nuclear Services
- T. R. Swift, Manager, Nuclear Quality Systems
- W. A. Goodwin, Director, Nuclear Quality Systems
- S. A. Toelle, Manager, Licensing
- J. M. Burger, Manager, Mechanical Systems E. A. Siegel, Manager, Plant Structures
- J. M. Betancourt, Senior Consulting Engineer, Licensing
- C. M. Molnar, Senior Consulting Engineer, Licensing i
- D. M. Amidon, Engineer, Quality Programs
)
- Attended exit meeting.
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l ORGANIZATION: COMBUSTION ENGINEERING INC.
1, POWER SYSTEMS GROUP WINDSOR. CONNECTICUT REPORT-INSPECTION NO.:. 99900401/88-01 RESULTS:
PAGE 10 of 10 TABLE I. PLANT USEAGE OF CE CONNECTORS IN CET AND RVLM SYSTEMS 1
i CET System RVLM System Plant (s)
Docket No.(s)
Conn. Type Conn. Clamped Braidwood 1, 2 50-456, 457 N/A only HJTCs Byron 1, 2 454, 455 N/A only(HJTCs Catawba 1, 2 413, 414 Litton-clamped N/A DP)
Comanche Peak 1, 2 445, 446 N/A Yes D.C. Cook 1, 2 315, 316 ERD N/A(DP)
Farley 1, 2 348, 364 ERD Yes Fort Calhoun 285 Litton Yes Haddam Neck 213 Litton-clamped N/A IndianPoint(future) 247 ERD N/A McGuire 1, 2 369, 370 Litton-clamped
~N/A(DP)
Millstone 2 336 Litton Yes Millstone 3 423 N/A Yes Palo Verde 1, 2, 3 528, 529, 530 Litton Yes Prairie Island 1, 2 282, 306 Litton N/A(DP)
St. Lucie 1, 2 335, 389 Litton Yes Salem 1, 2 272, 311 Litton Yes San Onofre 2, 3 361, 362 Litton Yes South Texas 1, 2 498, 499 N/A only(HJTCs Summer 395 Litton N/A DP)
Trojan 344 ERD
? (DP)
Turkey Point 3, 4 250, 251 Litton Yes WNP-3 508 Litton Yes Zion 1, 2 295 304 ERD Yes(DP) e N/A designates system and connectors not supplied by CE.
DP designates differential pressure level instrument.
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