ML20071B504

Forwards Revised Justification for Continued Operation, Correcting 830126 Submittal in Response to NRC 821227 SER Re Environ Qualification of safety-related Electrical Equipment

ML20071B504
Person / Time
Site:	Point Beach
Issue date:	02/18/1983
From:	Fay C WISCONSIN ELECTRIC POWER CO.
To:	Clark R, Harold Denton Office of Nuclear Reactor Regulation
References
IEB-79-01B, IEB-79-1B, NUDOCS 8302280366
Download: ML20071B504 (12)

Text

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lHsconsin Becinc meacoum 231 W. MICHIGAN, P.O. BOX 2046, MILWAUKEE, WI 53201 February 18, 1983 Mr. H. R. Denton, Director Office of Nuclear Reactor Regulation U. S. NUCLEAR REGULATORY COMMISSION Washington, D. C. 20555 Attention: Mr. R. A. Clark, Chief Operating Reactors Branch 3 Gentlemen:

DOCKET NOS. 50-266 AND 50-301 REV16ED RESPONSE REGARDING ENVIRONMENTAL QUALIFICATION OF SAFETY-RELATED ELECTRICAL EQUIPMENT POINT BEACH NUCLEAR PLANT, UNITS 1 AND 2 On December 27, 1982, Wisconsin Electric received the Safety Evaluation Reports (SER's) regarding the Environmental Qualification of Safety-Related Electrical Equipment at Point Beach Nuclear Plant, Units 1 and 2. On January 26, 1983 we transmitted our response to the SER's in which we reaffirmed the justifications for continued operation for Point Beach equipment items in NRC Qualification Category I.B, " Equipment Qualification Pending Modifications". This letter also contained an attachment which provided justification for continued operation for Point Beach equipment items identified in the SER's to be in NRC Qualification Category II.A, " Equipment Qualification Not Established". Due to the large-total volume of the SER's (approxi-mately 1,00~0 pages) and the short time available for the requested response (30 days) , the attachment to our January 26 letter contained several minor inaccuracies regarding the designation of the lubricants used in safety-related motors, pumps, and valve operators as well as the associated inspection and maintenance intervals. These inaccuracies were only identified after a detailed review of the attachment by the Point Beach Maintenance and Construction Superintendent. A revised justification for continued operation which corrects these inaccuracies and provides additional information is provided as an attachment to this letter.

These minor revisions do not change our judgment that Point Beach, Units 1 and 2, can continue to operate without undue risk to the public health and safety. We believe that the environ-mental qualification documentation already provided can be supplemented

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Mr. H. R. Denton February 18, 1983 for all Point Beach equipment items assigned to NRC Qualification Category II.A. This supplemental documentation will demonstrate environmental qualification to the provisions of the DOR Guidelines. It is our intention to request a meeting with your staff, specifically Equipment Qualification' Branch personnel, so that this' supplemental documentation can be reviewed. We will make arrangements for such a meeting through our NRC Project Manager as soon as the required additional documentation is assembled.

This letter is affirmed in accordance with the provisions of 10 CFR 50.54(f). We would be pleased to respond to any questions you may have in'this' matter.

Very truly yours, b f Vice Presi ent - Nuclear Power C. W. Fay Attachment Copy to NRC Resident Inspector Subscribed and sworn to before me this 4/gday of February 1983.

dWS WYb:_!& w Notary PdMlic, State of Wisconsin My Commission expires M.- /; /4 %Y.

. l Revision 1 2/18/83 1

JUSTIFICATION FOR CONTINUED OPERATION EQUIPMENT ITEMS IN NRC QUALIFICATION '

. CATEGORY II.A POINT BEACH NUCLEAR PLANT, UNITS 1 AND 2 SER Item PBNP Equipment No. Unit Description Justification for Continued Operation 24 1&2 Safety Injection 1. An analysis in the equipment qualification Pump Motors file justifies an in plant service life of (Westinghouse forty years as explained in Note T of our Thermalastic Epoxy October 11, 1981 response. Periodic in-Class B Insulation) service tests of the pumps performed monthly and meggar checks of the stator and lead wire insulation resistance performed at refueling intervals in accordance with the i PBNP maintenance call-up system should detect any unexpected degradation in the motor or associated leads.

2. The motor-to-lead splices were con-structed with silicon rubber tape (Scotch #70 or equivalent) insulation with a vinyl tape overall. Scotch #70tapegassatisfactorily tested for radiation (2x10 Rads gamma) and steam exposure in WCAP 7829. In addition, FRC Report F-C3694 documents the qualifica-tion including thermal aging of a similar silicon rubber insulation material used on instrumentation cable.

3. The motor bearing system consists of two split-sleeve-type, ring-oiled, radial journal bearings with a housing to keep out dirt and moisture. The motor bearings are lubricated with American Oil Co. ISO-Vg.

No. 68 or equivalent. This type of lubricant hasbeentestedsatisfactorilyforintegrated radiation doses in excess of 10 Rads gamma which exceeds the requirements for these motors.

The oil is replaced at two year intervals in accordance with the PBNP maintenance call-up system. The oil level and the bearing vibration and temperature are checked during operational checks of these pumps performed at monthly intervals in accord-l ance with PBNP inservice testing require-ments. The aging of the bearing / lubricant system is addressed by satisfactory service for over 12 years at PBNP.

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These motors (including the motor-to-lead splices and bearing / lubricant system) meet the qualification criteria of the D0R Guide-lines including the. aging criteria as clari-fied by NRC Generic Letter 82-09, Item 9.

Therefore, these motors are considered quali-fied to the provisions of the DOR Guidelines.

Additional documentation will be provQfed at a later time.

25 1&2 Containment Sprcy 1. See response to Item 24, Paragraphs 1 and Pump Motors 2, for justification for continued operation (Westinghouse Pre- regarding the thermal aging / service life of mium Moisture Re- the motor and the qualification of the motor-sistant Class B to-lead splices, respectively.

Insulation)

2. The motor bearing system consists of two shielded, anti-friction, radial, grease-lubricated, ball bearings with housings to keep out dirt and moisture. The bearing housing is greased at approximately three year intervals in accordance with the PBNP maintenance call-up system with a petroleum-based, lithium-soap-thickened grease. This type of lubricant has been tested satisfac-torily for 1 tegrated radiation doses in excess of 10 9Rads gamma which exceeds the requirements of these motors. These standby motors are checked for proper operation monthly including temperature and vibration measurements of the bearing system in accord-ance with PBNP inservice testing requirements as well as checked at refueling intervals by an operations refueling test. The aging of the bearing / lubricant system is addressed by satisfactory service for over 12 years at PBNP as well as tests of anti-friction bear-ings documented in WCAP 7829.

These motors (including the motor-to-lead splices and bearing / lubricant system) meet the qualifcation criteria of the DOR Guide-lines including the aging criteria as clari-fied by NRC Generic Letter 82-09, Item 9.

Therefore, these motors are considered qual-ified to the provisions of the D0R Guide-lines. Additional documentation will be pro-vided at a later time.

26 1&2 Component Cooling 1. See response to Item 24, Paragraphs 1 and Pump Motors 2, for justification for continued operation (Westinghouse Pre- regarding the thermal aging / service life of mium Moisture Re- the motor and the qualification of the motor-sistant Class B to-lead splices, respectively. No periodic Insulation) inservice tests are performed, however, be-

cause these motors are normally' operated for .

one month on and then one month off on a con-tinuous rotating basis.

2. The motor bearing system consists of two shielded, anti-friction, radial, grease-lubri-cated ball bearings with housings to keep out dirt and acisture. The bearing housing is greased at approximately one year intervals in accordance with the PBNP maintenance call-up system with a petroleum-based, lithium-soap-thickened grease. This type of lubricant has been tested satisfactorily for jntegrated radiation doses in excess of 10 Rads gamma which exceeds the requirements for these motors.

The operating component cooling pumps are checked for proper operation at least once per shift (about once every 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />) as required by the auxiliary operator's log sheets. The standby pumps are started and the operating pumps secured by a periodic check on a monthly-basis. The aging of the bearing / lubricant system is addressed by satisfactory service for over 12 years at PBNP as well as tests of anti-friction bearings documented in WCAP 7829.

These motors (including the motor-to-lead splices and bearing / lubricant system) meet the qualification criteria of the DOR Guide-lines including the aging criteria as clar-ified by NRC Generic Letter 82-09, Item 9.

Therefore, these motors are considered qual-ified to the provisions of the DOR Guidelines.

Additional documentation will'be provided at a later time.

27 1&2 Residual Heat 1. See response to Item 24, Paragraphs 1 and Removal Pump Motors 2, for justification for. continued operation

! (Westinghouse Therm-regarding the thermal aging / service life of

. alastic Epoxy Class the motor and the qualification of the motor-l B Insulation). to-lead splices, respectively.

2. The motor bearing system consists of two shielded, anti-friction, radial, grease-lubricated, ball bearings with housings to keep out dirt and moisture. The bearing housing is greased at approximately one year intervals in accordance with the PBNP main-tenance call-up system with a petroleum-based, lithium-soap-thickened grease. This type of lubricant has been tested satisfactorily foy integrated radiation doses in excess of 10 Rads gamma which exceeds the requirements

of these motors. These mot. ors are checked for proper operation monthly including temper-

3. ature and vibration measurements of the bear-ing system in accordance with PBNP inservice testing requirements as well as checkee at refueling intervals by an operations refueling test. The motors are also operated each refuel-

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ing during Residual Heat Removal system opera-tion. The aging of the bearing / lubricant system is addressed by satisfactory service for over 12 years at PBNP as well as tests of anti-friction bearings documented in WCAP 7829.

These motors (including the motor-to-lead splices and bearing / lubricant system) meet the qualification criteria of the DOR Guidelines including the aging criteria as clarified by NRC Generic Letter 82-09, Item 9. Therefore, these motors are considered qualified to the provisions of the D0R Guidelines. Additional documentation will be provided at a later time.

28 1&2 Containment Emer- 1. An aging analysis was performed which gency Fan Motors justifies an in plant service life (Westinghouse of forty years based on the qualifica-Thermalastic Epoxy tion tests documented in WCAPs 7829 Class F (Class A and 8754. Meggar checks of the motor and Temp. Rise) Insula- lead insulation resistance at refueling tion). intervals and disassembly, cleaning, inspection, and overhaul of the motor, as necessery, at every third refueling are performed in accordance with the.P8NP maintenance call-up system. This mainten-ance should detect any unexpected degrada-tion of the motor o- leads. The motor-to-lead splice and bearing / lubricant system qualification are addressed in items 29 and 53, respectively. These motors are con-l sidered qualified to the provisions of the DOR Guidelines.

2. The effects of plateout of Beta emitters l

on the stator insulation materials does not i have to be considered since the motor is totally enclosed. The only time the contain-ment atmosphere enters the enclosure is in the first ten seconds or so of an accident when a pressure equalization valve opens to admit enough air and/or steam to equalize pressure between the containment and the enclosure (see WCAP 7829, Figure 18). It is physically unrealistic for any radioactive fission products to have been released to the containment atmosphere in that time.

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l 29 1&2 Motor-to-Lead These splices were remade several years Splices for Item ago at PBNP to conform to the splices 28 -tested and qualified by WCAP 7829. Wes-tinghouse Drawing No. 206C391 is the basis  ;

for this splice. . Separate effects tests for radiation and steam exposure were also conducted satisfactorili on the individual splice materials. Therefore, the splice is considered qualified to the DOR Guide-lines.

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, ' 42 1&2 Okonite Instru- Documentation on our purchase orders estab-mentation Cable lish that the cable tested in FRC Test Report F-C3694 (Group II cables, Item 4A) is similar to our cable. The differences were analyzed and determined to have no effect on the qualification status of these cables. Our cables have a PVC jacket in lieu of an overall glass braid. The insula-tion material is identical as confirmed by a telephone conversation with Dr. Jack Lasky of Okonite Company. Therefore, this cable is considered qualified to the DOR Guide-

lines. Additional documentation will be pro-l vided later.

, 50 1&2 Safety Injection These pumps have one anti-friction, oil-Pump Bearing lubricated, radial, ball bearing and one anti-Lubricant (Ameri- friction, oil-lubricated, thrust ball bearing can Oil Co. Indus- with housings to hold the oil and to exclude trial No. 68 oil) dirt and moisture. This type of oil has been tested satisfactorily 7for integrated radiation doses in excess of 10 Rads gamma which exceeds the requirements for these pumps. The oil l 1evel and the bearing vibration and tempera-l ture are checked during operational checks of the pumps performed at monthly intervals in accordance with PBNP inservice testing re-quirements as well as during operation refueling tests. The oil is replaced at two year intervals in accordance with the PBNP maintenance call-up system. The aging of the bearing / lubricant system is also addressed by satisfactory service for over 12 years at PBNP as well as tests of anti-friction bearings documented in WCAP 7829.

T.he bearing / lubricant systems meet the qual-ification criteria of the DOR Guidelines including the aging criteria as clarified by the NRC Generic Letter 82-09, Item 9.

Therefore, these bearing / lubricant systems are considered qualified to the provisions i

of the DOR Guidelines. Additional documenta-I tion will be provided later.

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51 1&2 Component Cooling These pumps have one anti-friction, oil-Pump Bearing Lubri- lubricated, radial, hall bearing and one cant (American Oil anti-friction, oil-lubricated, thrust, ball Co. Industrial No. bearing with housings to hold the oil and to 46 oil) exclude dirt and moisture. This type of oil hasbeentestedsatisfactorilyforintegrated radiation doses in excess of 10 Rads gamma which exceeds the requirements for these pumps. The operating pump (one of two for each PBNP unit) is checked once each shift in accordance with the auxiliary operator log sheets. The standby pump is started and the operating pump secured at monthly intervals in accordance with the PBNP per-iodic check system. The oil is replaced at one year intervals in accordance with the PBNP maintenance call-up system. The aging of the bearing / lubricant system is also addressed by satisfactory service for over 12 years at PBNP as well as tests of anti-friction besrings documented in WCAP 7829.

ihe bearing /iubricant systems meet the qualification criteria of the DOR Guide-

< lines including the aging criteria as clarified by the NRC Generic Letter 82-09, Item 9. Therefore, these bearing / lubricant systems are considered qualified to the pro-visions of the DOR Guidelines. Additional documentation will be provided later.

52 1&2 Containment Spray These pumps have one anti-friction, oil-and RHR Pump Bear- lubricated, radial ball bearing and one anti-ing Lubricant friction, oil-lubricated, thrust, ball bearing (American Oil Co. with housings to hold the oil and to e>clude Rykon Industrial dirt and moisture. This type of oil has been No. 32 oil) tested satisfactorily 7for integrated radiation doses in excess of 10 Rads gamma which exceeds the requirements for these pumps. The oil level and bearing vibration and temperature are checked during operational checks of the pumps performed at monthly intervals in accordance with PBNP inservice testing re-quirements as well as operations refueling tests performed at refueling intervals. In

! addition, the RHR pumps are operated during I refueling outages during operation of the RHR l

system. The oil is replaced at one year in-tervals on the RHR pumps and three year inter-vals on the containment spray pumps, which are used for standby service only. The aging of the bearing / lubricant systems is also addressed by satisfactory service for over 12 years at PBNP as well as tests of anti-friction bearings documented in WCAP 7829.

The bearing / lubricant systems meet the qualification criteria of the DOR Guidelines including the aging criteria as clarified by the NRC Generic Letter 82-09, Iter 9.

Therefore, these bearing / lubricant systems are considered qualified to the

. provisions of.the DOR Guidelines.

Additional doccmentation will be provided later.

53 1&2 Containment Emer- The containment emergency fan cooler motors gency Fan Cooler use open anti-friction, grease-lubricated, Bearing Lubricant radial ball bearings with sealed housings.

(Chevron SRI The bearings are air-cooled by the same inte-grease) gral, air-to-water heat exchanger assembly which provides closed-cycle cooling and protection from accident environments for the motor. The bearings are checked and greased at refueling intervals with Chevron SRI grease in accordance with the PBNP maintenance call-up system.

The motors are disassembled including cleaning, inspection, and regreasing of the bearings every third refueling. The motors and fans are checked for proper operation including checks for noise, vibration, air and cooling water flow, and running current on a monthly inter-val in accordance with PBNP periodic l check and Technical Specification require-ments. In addition, the motors are normally running at approximately one-third design load and a vibration switch i

alarms in the control room if vibration exceeds a pre-set level. The bearing lubricant tested in the qualification tests documented by WCAP 7829 was Westing-house Style No. 773A773 which is Chevron BRB #2 grease. Chevron and Westinghouse both discontinued this grease several years ago but Chevron now supplies SRI grease which is documented to be equivalent (actually better) than BRB #2 grease.

The Chevron BRB #2 grease was tested for irradiation and " working" to simulate the conditions in containment following a design-basis LOCA as documented in the PBNP FSAR, pp. 6-3-16 through 19. The resultsshowthatthegreasewasstigl suitable after irradiation to 1.8x10 Rads gamma which exceeds the requirements of these motors. Based on the above e

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l l documentation and the satisfactory service at PBNP for over 12 years, it is concluded that the bearing / lubricant system will. perform its safety function satisfactorily. Additional documentation will be provided later.

. 2. The fan bearings consist of open anti-friction, grease-lubricated, spherical roller bearings with sealed pillow-block housings. The bearings and seals are

> disassembled, cleaned, inspected, and regreased at refueling intervals and the be.arings are greased once in between refuelings in accordance with the PBNP maintenance call-up system. The same.

grease is used for the fan bearing as described in paragraph 1 for the motor bearings (i.e., Chevron SRI). The grease used in the labyrinth seals of the bearing housings and qualified by WCAP 7829 was Westinghouse Style No. M-53701TT which is E.I. Dupont de Nemours & Co.,

Inc. Krytox 240 AC Fluorinated grease.

Based on the above documentation and the satisfactory service at PBNP for over 12 years, it is concluded that the bearing / lubricant system will perform its safety function satisfactorily.

Additional documentation will be provided later.

54 1&2 Limitorgue Valve These greases are petroleum-base greases Motor Operator with lithium or calcium-soap-thickeners and Lubricant (Ameri- extreme pressure (EP) additives. A number can Oil Co. Amolith of similar greases were yadiation tested

1. 1 EP or AMDEX #2 satisfactorily to 2.7x10 Rads and higher as EP greases) documented in an ASLE paper. This radiation level exceeds the requirements of these motor operators at PBNP. These operators are checked for proper operability at refueling intervals and/or quarterly in accordance with PBNP inservice testing requirements. These oper-ators are overhauled including replacement of greases at five year intervals in accor-dance with PBNP maintenance call-up system.

The greases have shown excellent service in over twelve years of operation at PBNP.

Similar greases have been used in numer-ous qualification tests of Limitorque

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operators under LOCA and SLBA conditions.

Therefore, continued safe operation of PBNP is assured until additional documentation is generated regarding similarity and aging.

, 55I 1&2 Pump Motor See response to Items 25, 26, and 27 regarding

! . Bearing Lubricant the motor bearing / lubricant system qualifica-(American Oil Co. tion.

Amolith #2 grease) 56 1&2 Limitorque Valve Mobil 28 grease is a synthetic lubricant Operator Geared which has been g radiation tested satisfac-Limit Switch torily to 3x10 Rads mixed gamma / neutron Assembly Lubricant radiation and tested satisfactorily in (Mobil Oil Co. bearings at temperatures of 580*F. These No. 28 grease) operators are checked for proper operabil-ity at refueling intervals and/or quarterly in accordance with PBNP inservice testing requirements. These operators are overhauled including replacement of greases at five-year intervals in accordance with the PBNP maintenance call up system. This grease is listed as an acceptable lubricant by Limitor-que for qualified Model SMB valve operators.

Therefore, this lubricant is considered qual-ified for use on all Limitorque valve oper-ator geared limit switch assemblies at PBNP.

61 1&2 Power Operateo This item is not required to mitigate a LOCA Relief Valve or HELB accident and is not considered Blocking Valve safety-related. Therefore, lack of quali-Limitorque Motor fication documentation does not affect Operators (Peer- plant safety.

Less Motor with Class B insulation) 62 1&2 Safety Injection These valves are administrative 1y maintained Line Valve in their required shut position for safety Limitorque Motor injection and are,therefore, not normally Operators (Peerless required to operate on receipt of a safety Motor with Class B injection signal. These valves may be insulation) opened within 14 hours1.62037e-4 days <br />0.00389 hours <br />2.314815e-5 weeks <br />5.327e-6 months <br /> of a small-break LOCA to aid in coolant mixing to prevent boron precipitation. As discussed in Mr. Sol Bursteins' letter to your staff l

dated May 7, 1975 regarding "ECCS Long Term 1 Cooling," boron precipitation is not a problem at PBNP even if these valves failed to open within 14 hours1.62037e-4 days <br />0.00389 hours <br />2.314815e-5 weeks <br />5.327e-6 months <br /> of a LOCA. There-l fore, PBNP can continue to operate safely i until this item is resolved.

.~ 1 63 1&2 Safety Injection Tnese valves are administrative 1y mairi-Line Valve tained open during normal operation which Limitorque Motor is their required position upon receipt Operators (Reli- of a safety injection signal. If these ance Motors with valves were initially closed, they would l Class B insulation) open immediately upon receipt of a safety injection signal. Their required operating

, time should be 1/2 hour and not 14 f.ours as stated on the SCEWs. Similar valve operators operated satisfactorily for 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> in simulated LOCA conditions as documented in WCAP 7410L. Therefore, PBNP can continue to operate safely until this item is resolved.

65 1&2 Auxiliary Feedwater Limitorque has confirmed that the valve Pump Steam Supply motor operators at PBNP.are identical Valve Limitorque to those tested in Limitorque Test Operators (Peerless Report No. 80003 except for the Peerless Motor with Class B motors. A Limitorque analysis has deter-Insulation) mined that Peerless motors with Class B insulation are equivalent to the Reliance motors with Class B insulation environmentally tested as documented in Limitorque Test Report No. B0003 and Westinghouse WCAP 7410-L.

Since the temperature / pressure profile used for qualification of these valves is extremely conservative, the operators are judged to be able to perform their safety function based on a combination of the two test reports. Since these valves are located in an area normally maintained between 65*F and 85*F and based on their satisfac-tory service for over 12 years at PBNP, no significant thermal aging degradation has occurred up to this point. Therefore, the continued safe operation of PBNP is assured l until this item is resolved.

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