ML17331A737

Forwards Addl Info to Util 810424 Submittal Re Distributed Ignition Sys Testing & Operation & Proposed Tech Specs & Preinstallation Testing Description of Glow Plug Igniters, in Response to NRC 810519 Request

ML17331A737
Person / Time
Site:	Cook
Issue date:	05/29/1981
From:	Hunter R INDIANA MICHIGAN POWER CO. (FORMERLY INDIANA & MICHIG
To:	Harold Denton Office of Nuclear Reactor Regulation
Shared Package
ML17331A738	List: ML17331A737 ML17331A739
References
AEP:NRC:00500C, AEP:NRC:500C, NUDOCS 8106030203
Download: ML17331A737 (9)

Text

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REGULATOR f INFORMATION DISTRIBUTION SYSTEM

~ (RIDS)

ACCESSION NBR:8106030203 OOC,DATE: 81/05/29 NOTARIZED: NO 4 FACIL:50-315 Donald C ~ Cook Nucl ear Pow'er PlantE Vni t 18 Indiana 0 QM3) 50 316 Donald CD Cook Nuclear Power Plant< Unit 2R Indiana AUTH ~ NAPE AUTHOR AFFILIATION HUNTERRR ~ ST Inrriana 8 ~schizan Electric Co, Director'OCKET REC I P, VA,>E RECIPIE >1 AFFILIATION OENTOtlRH ~ RE Office of Nuclear Reactor Regulationi SUBJECT; Forwards addi info to util 810424 submittal re distriouted ignition sys testing R operation 5 proposed Tech Specs preinstallation testing description of glow plug ignitorsE in response to NRC d10319 reauest ~

OISTRISUT ION CODE: ADO I 8 COPIES RECEIVED:LTR g ENCL SIZE: @+5 TITLE: General Distribution for after Issuance of Operating License NOTES: IIlE:3 copies all material. 05000315 Send 3 copies of all material to I8E ~ 05000316 RECIPIENT COPIES RECIPIENT COPIES ID CODE/<A"E L. Tl'R FNCL ID CODE/NAME LTTR ENCL ACTION: V ALGA 8 S ~ 04 13 13 INTERNAL: 0/DIREHUM FAC08 1 1 0 I R I 0 I jf OF L I C ICE Ob 2 2 NRC POR 02 OFLO 11 1 0 OR ASSESS BH 10 RAO ASsT BR 1 1 EG F I'CE 01 EXTERNAL: AC 1S 09 lo 16 LPDR NSIC 05 1 1 I(

TOTAL NUMBER OF COPIES REQUIRED: LTTR ENCL

4 INDIANA IIt MICHIGAN ELECTRIC COMPANY P. o. Box 18 80WLING GREEN STATION NEW YORK, N. Y. 10004 May 29, 1981 AEP:NRC:00500C U

Donald C. Cook Nuclear Plant Unit'Nos.".1 and 2

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Docket Nos. 50-315 and 50-316 License Nos. DPR-58 and DPR-74 Supplementary Information to AEP:NRC:00500A Mr. Harold R. Denton, Director Office of Nuclear Reactor Regulation U. S. Nuclear Regulatory Commission Washington, D. C. 20555

Dear Mr. Denton:

ty This letter and its attachments provide additional information'o our AEP:NRC:00500A submittal dated April 24, 1981 as per the reques't made by members of your staff during a telephone conversation held on May 19, 1981. In the attachments to this letter, supplementary information is included on the operation voltage and actuation procedures of the DIS, the proposed Technical Specifications and pre-installation testing description of the glow plug igniters. The proposed Technical Specifications have been reviewed and approved by the Plant Nuclear Safety Review Committee and will be reviewed by the AEPSC Nuclear Safety and Design Review Committee at its next meeting to be held on June 9, 1981. The potential for leakage flow into the instrument room is further addressed. Finally, a discussion on the containment air re-circulation fan survivability and on the possibility of ice condenser insulation degradation are also presented in the attach-ments.

As committed to in our letter to you of April 24, 1981, No.

AEP:NRC:0500A, the distributed ignition system installed in Cook Unit 2 will be fully operational by June 1, 1981.

'ery truly yours, gc oI R. S." Hunter.

/os Vice President (cc: attached)

Nr. Harold R. Denton AEP:NRC:00500C cc: John E. Dolan - Columbus R. W. Jurgensen R. C. Callen G. Charnoff D. U. Shaller Bridgman Region III Site Inspector - Bridgman

DONALD C. COOK NUCLEAR PLANT UNIT NOS. 1-AND 2 ATTACHMENT NO. 1 TO AEP:NRC:00500C

Attachment Ho. 1 to AEP:HRC:0500C I

1.0 0istributed~I~nition S stem Testin and 0 eration 1,1 Preb erational Testin The Distributed Ignition System (DIS) will be operated at 14 V ac.

An extensive pre-operational test program was undertaken to ensure that all glow plug igni ters being installed,in'he,Cook"Units >(ere capable

'f. achieving and maintaining a surface tempq'r~ture; of--",1550oF;ow gI eater -.

ap'14V ac operation. A'escr'iption of the test-psrograsm and a discussi'on of the test results follow.

A total of two hundred and eighteen (218) GM-AC glow plug igniters were purchased and tested; one hundred and thirty six (136) of which,

. sixty eight (68) per unit, have or will be installed as part of the Cook I Plant's DIS. A screening test w'as performed on all'the igniters so as to eliminate the potential for installation of defective plugs. The screening test consisted of energizing the igniters for approximately fifteen (15) minutes at 3, 6, and 9 V ac -followed'by'peration at 14 V ac for approximately fou) hours and fifteen minutes (total test him'e is five hours). Glow plug surface temperature was monitored using an optical pyrometer during the 14 V ac operation. *s aa, One hundred and eighty four (184) of the, glow-.plug 'igniters-success-,"

fully passed the'creening test.A random sam'pie'-of,.twenty this group and en'ergize'd for approximately-forty seven igniters'as'ele'cted from (47) hours at 14 V ac (no pre-warmin'g of the igniters was performed). All twenty igniters successfully passed this endurance test with a surface temperature in the range of 1900-2000oF. The remaining one hundred and sixty four (164) igniters were energized at 14 V ac directIy (no pre-warming) for approximately eight hours. All of these igniters success-fully passed this eight, hour test and exhibited a surface temperature in the range of 1900-2000oF.

Subsequent to installation, the DIS was further tested by energizing the supply breakers and measuring the voltage and amperage for the igniter groups. The igniters were visually inspected to verify proper operation (at surface temperatures in the range of 1900-2000oF the igniter glows a bright red).

1.2 Periodic Testin Proposed Technical Specifications for the DIS are contained in Attachment No. 2 to this submittal. Testing of the DIS will be accomplished by energizing the igniter groups and 'verifying that the voltage and amperage measurements taken during the'test are similar to the measurements taken during p.-'-operational testing of the system.

~,,0 Eighteen month surveillance will verify energization of the igniter through visual observation of the glow plug..

1.3 Actuation Criteria

/ The DIS is designed to provide additional hydrogen control cap-abilhty in the unlikely event of a degraded core cooling event in-volving the generation and release into containment, of substantive amounts of hydrogen. Conservative analyses of the containment response to deliberate hydrogen combustion have been performed utilizing the Westinghouse/Offshore Power System's (W/OPS) CLASIX computer code.

The. results of these analyses clearly reflect;,ttj'e ability', of the'DIS, in,conjunction with operation, of the Containment'ir Recirculation/

Hydrogen Skimmer System '(HYS) and the Containment- Spray System (CTS),

to provide adequate control for a S20 event resulting in (approximately)'ighty percent (80%) clad oxidation.

The W/OPS analysis of the S2D event shows th'at Automatic Phase would occur prior to the onset of hydrogen combustion. Phase'B'isolation

'B'ontainment isolation results in actuation of those systems, CTS and HYS, which are required to operate in conjunction with the DIS.

Therefor e, the DIS will be actuated subsequent to the receipt of an automatic Phase 'B'solation signal. Operation 'of -the'DIS is accom-plished by the use of four manual switch'es', two per train, located in the main control room.

2.0 Instrument Room Isolation

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In our AEP:NRC:00500A submittal we, stated that our preliminary review indicated that communication between the instrument room and other lower containment volume compartments was 'limited to the path through the hydrogen skirwer duct work and to potential in- leakage.

. Further review of this matter has revealed several pipe sleeves which are not sealed and a connection between the instrument room sump drain line and the pipe tunnel sump (2.5" diameter).. These small openings would provide paths for limited communication between the instrument room and the other lower volume compartments. We are continuing to review the necessity, or lack thereof-, of installing igniters in this area. We anticipate completion of our review prior to June 30, 1981.

3.0 Containment Air Recirculation/H dro en Skimmer Fan The survival of the containment air recirculation fans depends

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on the magnitude of the pressure differential which may be imposed across the fan in the event of an upper compartment hydrogen burn.

CLASIX results reported in AEP's earlier. submittal AEP:NRC:0500

. predicts a number of burns in the upper compartment. However, recent results of Sequoyah and McGuire analyses, obtained. from the modified version of the CLASIX code,"demonstrate that'hydrogen combustions occur. primarily in the upper plenum of the"ice-condenser and a number of them in the lower compartment.

The Cook specific CLASIX calculations will be done by OPS,in the near future arid as soon as the results become available, a final evaluation of the fans will be completed and the results submitted to the staff. We anticipate transmitting the results of our evaluation to you by June 30, 1981.

4.0 Ice Condenser Insulation The ice condensers in Cook Units 1 and 2 are very similar to those in McGuire and Sequoyah; the one difference which has been identified to be significant in the analysis of insulation degradation pertains to the type of insulation employed. Unlike McGuire or Sequoyah, w)ich employ polyurethane foam,'encapsulated fiberglass insulation is used at the Cook Plant. The insulation is covered by galvanized steel sheets with joints between panels sealed to prevent vapor penetration.

he casing material used to encapsulate the fiberglass is reported to be made of 6 mil polyethylene.

I Based on the heat transfer calculations performed on insulation heat-up for McGuire by Duke Power, the temperature of the surface adjacent to the insulation is estimated to be about 370oF'.the average, insulation temperature is approximately 265oF., Since the ice-condenser air duct configuration at Cook=is'omparable to McGuire's, the results reported by Duke are generally applicable to Cook.

Since fiberglass exhibits-:very stable material characteristics even at high temperatures,- its degrad'ation is not anticipated when

=exposed to thermal environments predicted by Duke Power.

According to Reference 1 polyethylene starts melting at 300 F and at about 600oF decomposition occurs. The energy content of polyethylene is reportedly somewhat higher than that of polyurethane, (20,000 Btu for polyethylene vs. 12,000 Btu for polyurethane).2 Tb Preliminary estimate on the total volume of this material used in each units ice-condenser indicates that only a very small amount of polyethylene is present as part of the insulation panels; and thus the total energy content of this material inside the ice-condenser is not expected to exceed that of, the intermediate deck doors cal-culated by Duke Power.

Therefore, based on analysis of the environment to which the insulation is exposed, it is unlikely that significant degradation of the polyethylene will occur; moreover, even in the event that all the polyethylene is decomposed, preliminary calculations indicate that this only constitutes a minuscule fraction of the energy generated from hydrogen combustion. Final'esults of the detailed study on the potential and impacts of insulation degradation in the Cook Plant ice-condensers will be submitted by June 30, 1981.

The Cook specific CLASIX calculations will be done by OPS in the near future and as soon as the results become available, a final evaluation of the fans will be completed and the results submitted to the staff. >!e anticipate transmitting the results of our evaluation to you by June 30, 1981.

4.0 Ice Condenser Insulation The ice condensers in Cook 'Units 1 and 2 are very similar to those in McGuire and Sequoyah; the one difference which has been identified to be significant in the analysis of insulation degradation pertains to the type of insulation employed. Unlike McGuire or Sequoyah, which employ polyurethane foam, encapsulated fiberglass insulation is used at the Cook Plant. The insulation is covered by galvanized steel sheets with joints between panels sealed to prevent vapor penetration.

The casing material used to encapsulate the fiberglass is reported to be made of 6 mi 1 polyethylene.

Based on the heat transfer calculations performed on insulation heat-up for McGuire by Duke Power, the temperature of the surface adjacent to the insulation is estimated to ge about 370oF'.the average ice-condenser insulation temperature is approximately 265>F. Since the air duct configuration at Cook is comparable to McGuire's, the results reported by Duke are generally applicable to Cook.

Since fiberglass exhibits very stable material characteristics even at high temperatures, its degradation is not anticipated when exposed to thermal environments predicted by Duke Power.

Accord'ing to Reference 1 polyethylene starts melting at 300 F and at about,'00oF decomposition occurs. The energy content of polyethylene's reportedly somewhat higher than that of polyurethane, (20,000 Btu f'r polyethylene vs. 12,000 Btu for polyurethane).2 Preliminary estimate on the total volume of this material used in each units ice-condenser indicates that only a very small amount of polyethylene is present as part of the insulation panels; and thus the total energy content of this material ins,ide the ice-condenser is not expected to exceed that of the intermediate deck doors cal-culated by Ouke Power.

Therefore, based on analysis of the environment to which the insulation is exposed, it is unlikely that significant degradation of the polyethylene will occur; moreover, even in the event that all the polyethylene is decomposed, preliminary calculations indicate that this only constitutes a minuscule fraction of the energy geherated from hydrogen combustion. Final results of the detailed study on the potential and impacts of insulation degradation in the Cook Plant ice-condensers will be submitted by June 30, 1981.

REFERENCES

1. Private Communication, T. McLaughlin of Dupont to K. K.- Shiu of AEP, Hay, 1981

2. Private Communication,.P. S. Cardello of Continental Wire 5 Cable Co.

to T. E. King of AEP, January 17, 1977.