Information Notice 1994-25, Failure of Containment Spray Header Valve to Open Due to Excessive Pressure from Inertial Effects of Water

Failure of Containment Spray Header Valve to Open Due to Excessive Pressure from Inertial Effects of Water

ML031060483
Person / Time
Site:	Beaver Valley, Millstone, Hatch, Monticello, Calvert Cliffs, Dresden, Davis Besse, Peach Bottom, Browns Ferry, Salem, Oconee, Mcguire, Nine Mile Point, Palisades, Palo Verde, Perry, Indian Point, Fermi, Kewaunee, Catawba, Harris, Wolf Creek, Saint Lucie, Point Beach, Oyster Creek, Watts Bar, Hope Creek, Grand Gulf, Cooper, Sequoyah, Byron, Pilgrim, Arkansas Nuclear, Three Mile Island, Braidwood, Susquehanna, Summer, Prairie Island, Columbia, Seabrook, Brunswick, Surry, Limerick, North Anna, Turkey Point, River Bend, Vermont Yankee, Crystal River, Haddam Neck, Ginna, Diablo Canyon, Callaway, Vogtle, Waterford, Duane Arnold, Farley, Robinson, Clinton, South Texas, San Onofre, Cook, Comanche Peak, Yankee Rowe, Maine Yankee, Quad Cities, Humboldt Bay, La Crosse, Big Rock Point, Rancho Seco, Zion, Midland, Bellefonte, Fort Calhoun, FitzPatrick, McGuire, LaSalle, Fort Saint Vrain, Shoreham, Satsop, Trojan, Atlantic Nuclear Power Plant
Issue date:	03/15/1994
From:	Grimes B Office of Nuclear Reactor Regulation
To:
References
IN-94-025, NUDOCS 9403210215
Download: ML031060483 (13)

UNITED STATES

NUCLEAR REGULATORY COMMISSION

OFFICE OF NUCLEAR REACTOR REGULATION

WASHINGTON, D.C. 20555 March 25, 1994 NRC INFORMATION NOTICE 94-25: FAILURE OF CONTAINMENT SPRAY HEADER VALVE TO

OPEN DUE TO EXCESSIVE PRESSURE FROM INERTIAL

EFFECTS OF WATER

Addressees

All holders of operating licenses or construction permits for nuclear power

reactors.

Purpose

The U.S. Nuclear Regulatory Commission is issuing this information notice to

alert addressees to the potential for valves to fail to open because of

unexpectedly high differential pressures caused by the inertial effects of

water moving in partially filled piping systems. It is expected that

recipients will review the information for applicability to their facilities

and consider actions, as appropriate, to avoid similar problems. However, suggestions contained in this information notice are not NRC requirements;

therefore, no specific action or written response is required.

Description of Circumstances

On September 13, 1993, at the Waterford Steam Electric Station, Unit 3, the

train A containment spray header isolation valve failed to open when it was

actuated following the successful completion of a test on the containment

spray system.

The containment spray system configuration includes a shutdown cooling heat

exchanger and two check valves located in the piping between a containment

spray pump and the subject isolation valve (Attachment 1). The isolation

valve is a 25-cm [10-inch] WKM solid gate valve, which is closed by air

pressure and opened by a spring, and is designed to open with a differential

pressure of 2070 kPa [300 psi] across the gate. The design rating of the

piping near the valve is 2170 kPa [300 psig] and the design shutoff head of

the pump is approximately 2000 kPa [275 psig].

During the test, the operators had successfully cycled the isolation valve

open and closed as required by the inservice surveillance testing program.

Subsequently, the operators started the containment spray pump. These two

functions are tested separately to prevent the actual spraying of water into

the containment. After completing this testing, the operators attempted to

open the isolation valve to refill the containment spray riser, but the valve

94032i02JS >

~ No-Kcc, qq-oA. 9 4q3)S

9403102$ >-z/C

IN 94-25 March 25, 1994 would not open. Therefore, the licensee declared train A of the containment

spray system Inoperable. The header subsequently became depressurized and the

operators were able to open the valve.

The licensee performed a special test on train A of the containment spray

system to determine the pressures that were developed in the piping. With the

isolation valve closed, the pump was started, run, and shut down while

pressure measurements were made at various locations in the piping. The

discharge pressure of the pump, which was run with minimum recirculation flow, was measured at 1900 kPa (260 psig]. The pressure at the inlet of the heat

exchanger, downstream of the first check valve, was measured at 2230 kPa

[308 psig]. The pressure between the second check valve and the containment

isolation gate valve reached 3330 kPa [469 psig] and then stabilized at

3210 kPa [450 psig], 1310 kPa [190 psi] higher than the pump discharge

pressure. Data gathered during this testing also indicated:that air had been

allowed to enter the piping system during maintenance activities.

Discussion

The licensee concluded that excessive differential pressure across the

isolation valve, which had developed during the earlier surveillance test, had

prevented the isolation valve from opening on September 13. Apparently the

air in the piping had allowed the pump discharge water to accelerate to a

higher-than-normal velocity. As the air was forced into the space between the

isolation valve and the check valves, it was compacted to a pressure that was

higher than the pump discharge pressure by the inertia (the hydraulic ram

effect) of the water. This excessive pressure was then trapped against the

isolation valve when the second check valve closed.

The licensee initially believed that the high pressure would occur only during

the surveillance tests because during an emergency actuation the isolation

valve was expected to open before the pump started. However, further

investigation revealed that, if offsite power was maintained, the containment

spray pump might start before the isolation valve opened. This could cause

the valve to remain shut under accident conditions. Consequently, as an

interim solution, the licensee has requested and received a technical

specification amendment allowing the train A isolation valve to remain open

during normal operation. In order to prevent the inadvertent spraying of the

containment, the licensee is taking compensatory measures such as-disabling

the pump or closing and disabling the isolation valve before performing

maintenance on the system.

The licensee performed an evaluation and determined that the system was not

degraded due to the overpressure condition. The licensee also performed

system evaluations on containment spray train B, and concluded that, due to a

shorter piping configuration and a better capability for venting this system, train B should be considered operable until a permanent solution is

• :IN 94-25 March 25, 1994 implemented. This conclusion was supported by testing which showed that, although somewhat higher-than-expected differential pressures did occur in

this train also, the containment isolation valve would consistently open.

The licensee is exploring various options for a permanent solution. These

include using a different isolation valve or delaying the pump starting time

to ensure that the isolation valve will open before pressure build-up can

occur.

The event illustrates that valve stroke-time inservice testing alone does not

ensure the capability of a valve to operate under all postulated design

conditions. This event also indicates that the inertia of water (hydraulic

ram effects) may not have been accounted for in the design of certain systems.

This information notice requires no specific action or written response. If

you have any questions regarding this matter, please contact one of the

technical contacts listed below or the appropriate Office of Nuclear Reactor

Regulation project manager.

Brian K. Grimes, Director

Division of Operating Reactor Support

Office of Nuclear Reactor Regulation

Technical contacts: Thomas F. Westerman, RIV Paula A. Goldberg, RIV

(817) 860-8145 (817) 860-8168 Linda J. Smith, RIV Patricia L. Campbell, NRR

(501) 968-3290 (301) 504-1311 Attachments:

1. Figure: Containment Spray System (Typical of Two Trains)

2. List of Recently Issued NRC Information Notices

7F

Containment Spray System

(Typical of Two Trains)

Isolation

Valve

Check Check

Pump Valve Valve

To

Pump - Containment

Suction- Sources

C

(D n0 %OM

I.."'1 Z-rt

Pto. s

rto

• w :s

%O

n -

Attachment 2 IN 94-25 March 25, 1994 LIST OF RECENTLY ISSUED

NRC INFORMATION NOTICES

Information Date of I

Notice No. Subject Issuance Issued to

Inadequate Maintenance 03/24/94 All holders of OLs or CPs

of Uninterruptible Power for nuclear power reactors.

Supplies and Inverters

94-23 Guidance to Hazardous, 03/25/94 All NRC Licensees.

Radioactive and Mixed

Waste Generators on the

Elements of a Waste

Minimization Program

94-22 Fire Endurance and 03/16/94 All holders of OLs or CPs

Ampacity Derating Test for nuclear power reactors.

Results for 3-Hour Fire- Rated Thermo-Lag 330-1 Fire Barriers

94-21 Regulatory Requirements 03/18/94 All fuel cycle and materials

when No Operations are licensees.

being Performed

Common-Cause Failures 03/17/94 All holders of OLs or CPs

due to Inadequate for nuclear power reactors.

Design Control and

Dedication

94-19 Emergency Diesel 03/16/94 All holders of OLs or CPs

Generator Vulnerability for nuclear power reactors.

to Failure from Cold

Fuel Oil

Accuracy of Motor- 03/16/94 All holders of OLs or CPs

Operated Valve Diag- for nuclear power reactors.

nostic Equipment

(Responses to Sup- plement 5 to Generic

Letter 89-10)

OL = Operating License

CP = Construction Permit

IN 94-25 March 25, 1994 implemented. This conclusion was supported by testing which showed that, although somewhat higher-than-expected differential pressures did occur in

this train also, the containment isolation valve would consistently open.

The licensee is exploring various options for a permanent solution. These

include using a different isolation valve or delaying the pump starting time

to ensure that the isolation valve will open before pressure build-up can

occur.

The event illustrates that valve stroke-time inservice testing alone does not

ensure the capability of a valve to operate under all postulated design

conditions. This event also indicates that the inertia of water (hydraulic

ram effects) may not have been accounted for in the design of certain systems.

This information notice requires no specific action or written response. If

you have any questions regarding this matter, please contact one of the

technical contacts listed below or the appropriate Office of Nuclear Reactor

Regulation project manager. Original signed by

Brian K, Grimes

Brian K. Grimes, Director

Division of Operating Reactor Support

Office of Nuclear Reactor Regulation

Technical contacts: Thomas F. Westerman, RIV Paula A. Goldberg, RIV

(817) 860-8145 (817) 860-8168 Linda J. Smith, RIV Patricia L. Campbell, NRR

(501) 968-3290 (301) 504-1311 Attachments:

1. Figure: Contai nment Spray System (Typical of Two Trains)

2. List of Recentl y Issued NRC Information Notices

• SFF PRFVIOUS CONCURRENCE

OFFICE *OGCB/NRR *TECH ED *REGION IV *REGION IV *REGION IV

NAME DCKirkpatrick RSanders TFWesterman PAGoldberg LJSmith l

DATE j 12/06/93 12/08/93 ,01/11/94 01/11/94 101/11/94

• EMEB/DE *C:EMEB/DE *D:DE *PDIV-1 *REGION IV *C:EAB/DORS

PCampbell JNorberg MWHodges DWigginton SCollins AChaffee

01/05/94 01/05/94 01/06/94

7 j01/10/

7_ i It/

01/11/94 01/28/94

• C:SCSB/DSSA *AC:OGCB/DORS D WN R fr

RLobel for AJKugler / d

RBarrett __

02/10/94 03/03/94 03/Z//94 DOCUMENT NAME: 94-Zb.IN

IN 94-xx

March xx, 1994 implemented. This conclusion was supported by testing which showed that, although somewhat higher-than-expected differential pressures did occur in

this train also, the containment isolation valve would consistently open.

The licensee is exploring various options for a permanent solution. These

include using a different isolation valve or delaying the pump starting time

to ensure that the isolation valve will open before pressure build-up can

occur.

The event illustrates that valve stroke-time inservice testing alone does not

ensure the capability of a valve to operate under all postulated design

conditions. This event also indicates that the inertia of water (hydraulic

ram effects) may not have been accounted for in the design of certain systems.

This information notice requires no specific action or written response. If

you have any questions regarding this matter, please contact one of the

technical contacts listed below or the appropriate Office of Nuclear Reactor

Regulation project manager.

Brian K. Grimes, Director

Division of Operating Reactor Support

Office of Nuclear Reactor Regulation

Technical contacts: Thomas F. Westerman, RIV Paula A. Goldberg, RIV

(817) 860-8145 (817) 860-8168 Linda J. Smith, RIV Patricia L. Campbell, NRR

(501) 968-3290 (301) 504-1311 Attachments:

1. Figure: Cont ainment Spray System (Typical of Two Trains)

2. List of Recen tly Issued NRC Information Notices

• SEE PREVIOUS CONCURRENCE

OFFICE *OGCB/NRR *TECH ED *REGION IV *REGION IV *REGION IV

NAME DCKirkpatrick RSanders TFWesterman JPAGoldberg LJSmith

DATE ,12/06/93 1 12/08/93 01/11/94 J01/11/94 , 01/11/94

• EMEB/DE *C:EMEB/DE *D:DE *PDIV-1 *REGION IV *C:EAB/DORS

PCampbell JNorberg MWHodges DWigginton SCollins AChaffee

01/05/94 ,01/05/94

_ , _

101/06/94 01/10/94 101/11/94 , 01/28/94

• C:SCSB/DSSA *AC:OGCB/DORS I D:DORS/NRR

RLobel for AJKugler BKGrimes

RBarrett

02/10/94 03/03/94 02/ /94 DOCUMENT NAME: HYDRORAM.DCK

IN 94-xx

March xx, 1994 implemented. This conclusion was supported by testing which proved that, although somewhat higher-than-expected differential pressures did occur in

this train also, the containment isolation valve would consistently open.

The licensee is exploring various options for a permanent solution. These

include using a different isolation valve or delaying the pump starting time

to ensure that the isolation valve will open before pressure build-up can

occur.

The event indicates that valve stroke-time inservice testing does not ensure

the capability of a valve to operate under all postulated design conditions.

This event also indicates that hydraulic ram effects may not have been

accounted for in the design of certain systems.

This information notice requires no specific action or written response. If

you have any questions regarding this matter, please contact one of the

technical contacts listed below or the appropriate Office of Nuclear Reactor

Regulation project manager.

Brian K. Grimes, Director

Division of Operating Reactor Support

Office of Nuclear Reactor Regulation

Technical Contacts: Thomas F. Westerman, RIV Paula A. Goldberg, RIV

(817) 860-8145 (817) 860-8168 Linda J. Smith, RIV Patricia L. Campbell, NRR

(501) 968-3290 (301) 504-1311 Attachment:

List of Recently Issued NRC Information Notices

• SEE PREVIOUS CONCURRENCE

OFFICE *OGCB/NRR *TECH ED *REGION IV *REGION IV *REGION

NAME DCKirkpatrick RSanders TFWesterman PAGoldberg LJSmith

DATE 12/06/93 12/08/93 01/11/94 01/11/94 01/11/94

• EMEB/DE *C:EMEB/DE *D:DE *PDIV-1 *REGION IV *C:EAB/DORS

PCampbell JNorberg MWHodges DWigginton SCollins AChaffee

01/05/94 , 01/05/94 ,01/06/94

.

, 01/10/94

.1

,01/11/94 101/28/94

• C:SCSB/DSSA AC:OGCB/DORS D:DORS/NRR

RLobel for AJKugler BKGrimes I

RBarrett 0

_____ /94

02/10/94 0~o3/94 02/ /94 DOCUMENT NAME: HYDRORAM.DCK

IN 94-xx

January xx, 1994 implemented. This conclusion was supported by testing which proved that, although somewhat higher-than-expected differential pressures did occur in

this train also, the containment isolation valve would consistently open.

The licensee is exploring various options for a permanent solution. These

include using a different isolation valve or delaying the pump starting time

to ensure that the isolation valve will open before pressure build-up can

occur.

The event indicates that valve stroke-time inservice testing does not ensure

the capability of a valve to operate under all postulated design conditions.

This event also indicates that hydraulic ram effects may not have been

accounted for in the design of certain systems.

This information notice requires no specific action or written response. If

you have any questions regarding this matter, please contact one of the

technical contacts listed below or the appropriate Office of Nuclear Reactor

Regulation project manager.

Brian K. Grimes, Director

Division of Operating Reactor Support

Office of Nuclear Reactor Regulation

Technical Contacts: Thomas F. Westerman, RIV Paula A. Goldberg, RIV

(817) 860-8145 (817) 860-8168 Linda J. Smith, RIV Patricia L. Campbell, NRR

(501) 968-3290 (301) 504-1311 Attachment:

List of Recently Issued NRC Information Notices

• SEE PREVIOUS CONCURRENCE

OFFICE *OGCB/NRR *TECH ED *REGION IV *REGION IV *REGION

NAME DCKirkpatrick RSanders TFWesterman PAGoldberg LJSmith J

DATE 12/06/93 12/08/93 01/11/94 01/11/94 01/11/94

• EMEB/DE *C:EMEB/DE *D:DE l *PDIV-1 l *REGION IV *C:EAB/DORS

PCampbell JNorberg MWHodges DWigqinton SCollins AChaffee

F

01/05/94 , 01/05/94 01/06/94 !01/10/94 I01/11/94 01/28/94 SSA AC:OGCB/DORS D:C )ORS/NRR

r< AJKugler BK(Grimes

0 /a/ 02/ /94 02/

/ /94 DOCU NAME: HYDRORAM.DCK

to jQ&

sC

.I

IN 94-xx

January xx, 1994 implemented. This conclusion was supported by testing which proved that, although somewhat higher-than-expected differential pressures did occur in

this train also, the containment isolation valve would consistently open.

The licensee is exploring various options for a permanent solution. These

include, using a different isolation valve or delaying the pump starting time

to ensure that the isolation valve will open before pressure build-up can

occur.

The event indicates that valve stroke-time inservice testing does not ensure

the capability of a valve to operate under all postulated design conditions.

The event also indicates that hydraulic ram effects may not have been

accounted for in the design of certain systems.

This information notice requires no specific action or written response. If

you have any questions regarding this matter, please contact one of the

technical contacts listed below or the appropriate Office of Nuclear Reactor

Regulation project manager.

Brian K. Grimes, Director

Division of Operating Reactor Support

Office of Nuclear Reactor Regulation

Technical Contacts: Thomas F. Westerman, Region IV

(817) 860-8145 Paula A. Goldberg, Region IV

(817) 860-8168 Linda J. Smith, Region IV

(501) 968-3290

• SEE PREVIOUS CONCURRENCE

OFFICE *OGCB/NRR *TECH ED *REGION IV *REGION IV *REGION

NAME DCKirkpatrick RSanders TFWesterman PAGoldberg LJSmith

DATE 12/06/93 12/08/93 01/11/944

• EMEB/DE *C:EMEB/DE I *D:DE *PDIV-1 *REGION IV I C:EkBJDAZ%

PCampbell JNorberg MWHodges DWigginton SCollins e V

DCh P

01/05/94 01/05/94 I 01/06/94 01/10/94 01/11/94 01A/ I

I - - 1 I_ _ _- _ _ _ _ _ _

C:OGCB/DORS D:DORS/NRR

0c I2)t , . ,

Ck~A . GHMarcus BKGrimes i1 I -dr qW

01/ /94

-4.

01/ /94 D ,UMNNAE . HYDRORAM.DCK

DOCUMENT NAME:

D. A.D

IN 94-xx

January xx, 1994 supported by testing which proved that, although somewhat higher-than-expected

differential pressures did occur in this train also, the containment isolation

valve would consistently open.

The licensee is exploring various options for a permanent solution. These

include, using a different isolation valve or delaying the pump starting time

to ensure that the isolation valve will open before pressure build-up can

occur.

The event indicates that valve stroke-time inservice testing does not ensure

the capability of a valve to operate under all postulated design conditions

such as water hammer. The event also indicates that water hammer effects may

not have been accounted for in the design of certain systems.

This information notice requires no specific action or written response. If

you have any questions regarding this matter, please contact one of the

technical contacts listed below or the appropriate Office of Nuclear Reactor

Regulation project manager.

Brian K. Grimes, Director

Division of Operating Reactor Support

Office of Nuclear Reactor Regulation

Technical Contacts: Thomas F. Westerman, Region IV

(817) 860-8145 Paula A. Goldberg, Region IV

(817) 860-8168 Linda J. Smith, Region IV

(501) 968-3290

• SEE PRFVTAiS rnNCURRFNCF

OFFICE *OGCB/NRR *TECH ED REGION IV REGION IV REGION IV

NAME DCKirkpatrick RSanders TFWesterman PAGoldberg LJSmith

DATE 12/06/93 12/08/93 01/ /94 101/ /94 01/ /94 J

• EMEB/DE IC . D:DE. 1.,4 1lPDII--- l REGION IV liC;. AdV/ ?)5)

PCamDbell Jo rbre' qg I MWHoges DW MY inton I SCollins I Cc

01/05/94 i 01/ 794 01/ U/944 41r 01//1/94 i 1!/9J To/,/ '?d('

-~~ .1 I- d

D:DORS/NRR ll #1VAN

C:OGCB/DORS

GHMarcus BKGrimes

a

01/ /94 01/ /94 DOCUMENT NAME: HYDRORAM.VLK

IN 94-xx

January xx, 1994 This information notice requires no specific action or written response. If

you have any questions regarding this matter, please contact one of the

technical contacts listed below or the appropriate Office of Nuclear Reactor

Regulation project manager.

Brian K. Grimes, Director

Division of Operating Reactor Support

Office of Nuclear Reactor Regulation

Technical Contacts: Thomas F. Westerman, Region IV

(817) 860-8145 Paula A. Goldberg, Region IV

(817) 860-8168 Linda J. Smith, Region IV

(501) 968-3290

• SEE PREVIOUS CONCURRENCE

OFFICE *OGCB/NRR *TECH ED REGION IV REGION IV REGION IV

NAME DCKirkpatrick RSanders TFWesterman PAGoldberg LJSmith

DATE 112/06/93 J12/08/93 101/ /94 101/ /94 ,01/ /94 J

EMEB/DEc ,1lC: EMEB/DE l PDIV-1 REGION IV

PCampbell JNorberg I V; l DWigginton SCollins

01/ b/94 01/ /94 [01/ /94 1 01/ /94 1101/ /94 ]

C:OGCB/DORS D:DORS/NRR I

GHMarcus BKGrimes

01/ /94 01/ /94 DOCUMENT NAME: HYDRORAM.DCK

'IL K>

IN 93-xx

December xx, 1993 This information notice requires no specific action or written response. If

you have any questions regarding this matter, please contact one of the

technical contacts listed below or the appropriate Office of Nuclear Reactor

Regulation project manager.

Brian K. Grimes, Director

Division of Operating Reactor Support

Office of Nuclear Reactor Regulation

Technical Contacts: Thomas F. Westerman, Region IV

(817) 860-8145 Paula A. Goldberg, Region IV

(817) 860-8168 Linda J. Smith, Region IV

(501) 968-3290

OFFICE OGCB/NRR TECH ED REGION IV REGION IV REGION IV

NAME DCKirkpatrick R. J44tdeA4- TFWesterman PAGoldberg LJSmith

DATE 12/1 /93 112/S /93 12/ /93 12/ /93 112/ /93 EMEB/DE C:EMEB/DE I D: DE PDIV-1 REGION IV

PCampbell JNorberg JTWiggins J DWigginton j SCollins

12/ /93 12/ /93 1

112/ /93 12/ 9

/93 C:OGCB/DORS D:DORS/NRR I1 GHMarcus BKGrimes

12/ /93 NAM: HYUKUKAM1.UCK

r

UULUUMtNi