ML19207B426

Forwards Request for Addl Info on Steam Generator Water Hammer to Be Sent to Westinghouse & C-E Licensees,For Plants Not Equipped W/Top Discharge Devices on Steam Generator Feedwater Sys & for Which No Mods Are Planned

ML19207B426
Person / Time
Site:	Palisades, Kewaunee, Point Beach, Prairie Island, Turkey Point, Haddam Neck, Robinson, San Onofre, Yankee Rowe, Maine Yankee, Fort Calhoun
Issue date:	08/02/1979
From:	Lainas G Office of Nuclear Reactor Regulation
To:	Reid R, Schwencer A Office of Nuclear Reactor Regulation
References
TASK-05-13, TASK-RR NUDOCS 7908290180
Download: ML19207B426 (7)

Text

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g NUCLEAR REGULATORY COMMISSION 3.** \\ ^ '

E WASHINGTON, D. C. 20555

g 21T9 MEMORANDUM FOR

A. Schwencer, Chief, Operating Reactors Branch #1, 00R R. Reid, Chief, Operating Reactors Branch #4, 00R FROM:

G. Lainas, Chief, Plant Systems Branch, 00R

SUBJECT:

REQUEST FOR ADDITIONAL INFORMATION ON STEAM GENERATOR WATER HAMMER The enclosed request for additional information should be sent to those licensees for Westinghouse and Combustion Engineering plants that are not equipped with top discharge devices on the steam generator feedwater spargers and for which there are no plans co modify the feedwater systems to reduce the probability of steam generator water hamer.

Those plants are listed in the enclosure. Although a steam generator water hammer has not occurred in the present piping systems of those plants, we require some basis for further assurance that it will not occur in the future, that the capability exists for the detection of water hammer and that the NRC would be notified of such an event.

/&

G. Lainas, Chief Plant Systems Branch Division of Operating Reactors

Contact:

S. MacKay X27110

Enclosure:

As stated cc w/ enclosure:

See next page 857 315 790829oggo

cc w/ enclosure:

D. Eisenhut B. Grimes S. Hanauer V. Benaroya G. Lainas E. Adensam E. Reeves S. MacKay Y. Huang D. Christier.sen (EG&G)

J. Reece (Consultant) 857

, ENCLOSURE 1 To PWR licensees for the following plants:

Haddam Neck Kewaunee Point Beach 1 and 2 Robinson 2 Prairie Island 1 and 2 San Onofre 1 Turkey Point 3 and 4 Yankee Rowe Ft. Calhoun Maine Yankee Palisades Gentlemen:

PE: STEAM GENERATOR WATER HAMMER In response to our letter of September 2,1977 regarding steam generator water hamer you indicated that, based on your operating experience, modifications were not necessary to further reduce the probability or consequences of steam generator water hammer at your facility. Although your operating history does not show that such water hamer has occurred in your present piping arrangement, we require further assurance that steam generator water hame. will not occur in the future and that surveillance procedures would be adequate to detect water hamer or damage from water hammer if it were to occur.

Your response to the enclosed request for infomation, together with pre-viously supplied infomation, will provide a basis for a detennination reprding the need for modifications to your feedwater system to prevent steam generator water hammer. Your respor.se is needed within 30 days so that we may maintain our e; hedule for evaluating the potential for water hamer at your facility.

Chief, Ooerating Reactors Branch #

7*7 Division of Operating Reactors 857 a

ENCLOSURE 1 REQUEST FOR INFORMATION REGARDING THE POTENTIAL FOR STEAM GENERATOR WATER HAMMER AT PRESSURIZED WATER REACTORS WITH FEEDRINGS THAT DISCHARGE FROM THE BOTTOM AUGUST 1979 857 MB

1.

Provide information that demonstrates that the feedwater system and steam generator water level at your facility have been subjected to those transient conditions most conducive to water harrer that might be expected as a result of normal operation as well as transients and accidents.

Include the following:

1.1 Describe the expected behavior of steam generator water level as a r;esult of reactor trip from power levels greater than 30". of full power.

Include actual plant measurements of steam generator level and other available related data such as feedwater flow and au:.iliary feedwater ficw.

1.2 Provide the number and causes of loss of feedwater esents during the operational history of the plant.

1.3 Provide the number and causes of loss of off-site power events during the operational history of the plant.

2.

If administrative controls have been adopted to limit the flow of auxiliary feedwater for the purpose of reducing the probability of water hammer, show when they were adopted and give the answers to items 1.1 1.2 and 1.3 for before and after such controls were established.

3.

If administritive controls have been adopted to limit the flow of auxiliary feedwater for the purpose of reducir; the probability of water hammer, show that an adequate water inventory and flow will be maintained to accomodate all postulated transient and accident conditions.

4.

Provide copies of the procedures for governing the control of auxiliary feedwater ficw during normal and emergency operations.

71g 857 ot 5.

NUREG 0578, "TMI-2 Lessons Learned Task Force Status Report and Short Term Recommendations," that was fomarded to you on July 25, 1979, includes the recommendation (page A-31) that the flow of auxiliary feecwater be initiated automatically. Regardless of whether such initiaHon is presently automatic at your facility, please list the signals that will automatically initiate the flow of auxiliary feedwater including the steam generator water level set point. This set point should be above the top of the main feedwater nozzle to reduce the probability of steam generator water hammer.

6.

If auxiliary feedwater flow in your facility is not at present initiated automatically for normal and accident events, present your evaluation of whether automating the actuation of auxiliary feedwater might increase the probability of inducing steam generator water hammer.

If such automation might increase the probability of water hammer in your facility please reconsider the need for modifications to prevent water hammer.

7.

Describe the means that will be used to conitor for the occurrence of steam generator water hamer and possible damage from such an event.

Include all instrumentation that will be employed.

Describe the inspections that will be perforned and give the frequency of such inspections.

8.

Describe the reporting procedures that will be used to document and report water hamer and damage to piping and piping support systems.

Such incidents occurring in safety relatd systems should be reported to the NRC within 30 days.

Since part of the main feedwater piping is used for the delivery of auxiliary feedwater and a water hamer in the feed-857 320

. water system can be transmitted throughout the system, all water hanmers in the main feedwater system should also be reported.

857 321