Information Notice 1988-01, Safety Injection Pipe Failure

Safety Injection Pipe Failure

ML031150675
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, 05000000, Zimmer, Fort Saint Vrain, Shoreham, Satsop, Trojan, Atlantic Nuclear Power Plant
Issue date:	01/27/1988
From:	Rossi C Office of Nuclear Reactor Regulation
To:
References
IN-88-001, NUDOCS 8801210097
Download: ML031150675 (10)

A

UNITED STATES

NUCLEAR REGULATORY COMMISSION

OFFICE OF NUCLEAR REACTOR REGULATION

WASHINGTON, D.C. 20555 January 27, 1988 NRC INFORMATION NOTICE NO. 88-01: SAFETY INJECTION PIPE FAILURE

Addressees

All holders of operating licenses or construction permits for nuclear power

reactors.

Purpose

This information notice is to alert addressees to a potentially generic problem

concerning the reliability of piping in safety-related systems-due to valve

leakage which results in thermal cycling of the piping. Recipients are expected

to review the information for applicability to their facilities and consider

actions, if appropriate, to preclude similar problems from occurring at their

facilities. However, suggestions contained in this information notice do not

constitute NRC requirements; therefore, no specific action or written response

is required.

Description of Circumstances

On December 9, 1987, while restarting Farley Unit 2 after a refueling outage, the licensee noted increased moisture and radioactivity within containment.

The unidentified leak rate for the RCS was determined to be 0.7 gpm. After

entering containment to identify the location of the leak, licensee personnel

determined that the leak could not be isolated. The reactor, which was at

33 percent power, was shut down to facilitate repair.

By ultrasonic testing, the licensee found an indication of a crack on the

interior surface of the 6-inch ECCS piping connected to the cold leg of RCS

Loop B. The indication was located at a weld connecting an elbow and a hori- zontal spool, as shown in Attachment 1. Further, the indication was on the

underside of the pipe and extended circumferentially 60 degrees in both direc- tions from the bottom of the pipe. The crack extended through the wall for

approximately 1 inch at the center of the indication. Visual and metallo- graphic examinations showed that the weld had failed as a result of fatigue

after roughly one million stress cycles. The licensee examined the operating

records and determined that the number of stress cycles imposed by starting up

and shutting down and by safety injections was significantly less than the

relevant design criteria.

8801210097

IN 88-01 January 27, 1988 On the basis of this information, the licensee postulated

loads were (1) thermal and created by valve leakage or that the stress

or (2) mechanical and created by flow-induced vibrations.convective flow cells

lations, the licensee replaced the failed piping and installed To test these postu- temperature and acceleration near the location of the sensors for

failed weld and at a

location 25 to 30 inches upstream from the failed weld, side of the check valve. The licensee also installed that is, on the other

tions on the ECCS pipe connected to Loop C. At each sensors at similar loca- were distributed circumferentially around the pipe. location the sensors

Data from the sensors demonstrated that there was an adverse

bution in the Loop B ECCS piping as shown in Attachment temperature distri- temperature difference at the location of the failed weld 1. The circumferential

the temperature at the bottom of the pipe fluctuated as was 2150 F. Further, seconds. This spatial and temporal distribution was caused much as 300 F in 30

valve in the bypass pipe around the boron injection tank by failure of the

The valve, which is shown in Attachment 2, is believed (BIT) to seat properly.

failure of the weld. Leakage through the valve apparentlyto be the cause of

valves in the Loop B ECCS pipe to partially open, or caused the check

tively cold coolant to the unisolable portion of the chatter, admitting rela- and the first check valve. Temporarily redirecting thepipe between the nozzle

valve

from the ECCS manifold changed the temperature distribution, leakage away

Attachment 1. It should be noted that there may be other as shown in

in both PWRs and BWRs which could experience similar fatigue safety-related piping

cycling. due to thermal

Data from the temperature sensors for Loop C indicated

in that pipe were not chattering and that the temperature that the check valves

normal. Further, none of the accelerometers indicated distribution was

stress cycling. adverse mechanical

Examination of the analysis of record for the small-break, accident indicated that double-ended failure of the unisolable loss-of-coolant

not have been enveloped. ECCS pipe may

Discussion:

A generic safety question may exist for those plants having

that are used for charging the RCS with coolant during dual purpose pumps

normal

injecting emergency core coolant at high pressure following operation and

normal operation, with one of the pumps providing charging an accident. During

the normal charging piping and with a leaking valve allowing flow to the RCS via

the ECCS manifold, pressure in the manifold will exceed coolant to flow to

valves in the ECCS piping will open admitting relatively RCS pressure and check

The flow rate via this additional path or paths is determinedcold coolant to the RCS.

that occurs in the leaking valve. If the check valves by the throttling

pipe open, then more than one unisolable ECCS failure in more than one ECCS

may occur. Subjecting

the flawed piping to excessive stresses induced by a seismic

or some other cause conceivably could result in simultaneous event, water hammer, of more than one ECCS pipe. double-ended failure

IN 88-01 January 27, 1988 Corrective action for this common-mode failure would include redesigning the

piping, instrumenting unisolable and adjacent portions of the piping to detect

cyclic or abnormal thermal stresses, instrumenting the ECCS manifold to detect

pressure resulting from valve leakage, or providing additional surveillance.

No specific action or written response is required by this information notice.

If you have any questions about this matter, please contact the technical

contact listed below or the Regional Administrator of the appropriate regional

office.

Ch .El:.

Ros Dfrector

Division of Operational Events Assessment

Office of Nuclear Reactor Regulation

Roger Woodruff, NRR

(301) 492-7096 Attachments:

1. Farley 2 Temperature Data

2. Farley 2 ECCS

3. List of Recently Issued NRC Information Notices

t.1A .

WITH WiTHOUT

LEAKAGE LEAKAGE

TOP OF PiPE 40F 495F

BOTTOM OF PIPE 225F 490F

' WITH WiTHOUT

LEAKAGE LEAKAGE

TOP OF PIPE I200F

cI

BOTTOM OF P11PE 245F117F  ; 115F

!r

I 8 Eccs

FAILED WI

la

COLD LEG iB

A~~ wC

I

A

m

z

-I

FARLEY 2 TEMPERATURE DATA

r1

ECCS TO RCS

COLD LEGS

NbRMAL CHARGiNG

TO RCS COLD LEG B

(

CHARGiNG/HiGH

PRESSURE SAFETY

INJECTION PUMPS

30

x

m

2 FARLEY 2 ECCS I

h3

,. .

I

Attachment 3- IN 88-01 January 27, 1988 LIST OF RECENTLY ISSUED

NRC INFORMATION NOTICES

Information Date of

Notice No. Subject Issuance Issued to

86-81, Broken External Closure 1/11/88 All holders of OLs

Supp. 1 Springs on Atwood & Morrill or CPs for nuclear

Main Steam Isolation Valves power reactors.

87-67 Lessons Learned from 12/31/87 All holders of OLs

Regional Inspections of or CPs for nuclear

Licensee Actions in Response power reactors.

to IE Bulletin 80-11

87-66 Inappropriate Application 12/31/87 All holders of OLs

of Commercial-Grade or CPs for nuclear

Components power reactors.

87-28, Air Systems Problems at 12/28/87 All holders of OLs

Supp. 1 U.S. Light Water Reactors or CPs for nuclear

power reactors.

87-65 Plant Operation Beyond 12/23/87 All holders of OLs

Analyzed Conditions or CPs for nuclear

power reactors.

87-64 Conviction for Falsification 12/22/87 All nuclear power

of Security Training Records reactor facilities

holding an OL or CP

and all major fuel

facility licensees.

87-35, Reactor Trip Breaker 12/16/87 All holders of OLs

Supp. 1 Westinghouse Model DS-416, or CPs for nuclear

Failed to Open on Manual power reactors.

Initiation From the Control

Room

87-63 Inadequate Net Positive 12/9/87 All holders of OLs

Suction Head in Low Pressure or CPs for nuclear

Safety Systems power reactors.

87-62 Mechanical Failure of 12/8/87 All holders of OLs

Indicating-Type Fuses or CPs for nuclear

power reactors.

OL = Operating License

CP = Construction Permit

IN 88-01 January 27, 1988 Corrective action for this common-mode failure would include redesigning the

piping, instrumenting unisolable and adjacent portions of the piping to detect

cyclic or abnormal thermal stresses, instrumenting the ECCS manifold to detect

pressure resulting from valve leakage, or providing additional surveillance.

No specific action or written response is required by this information notice.

If you have any questions about this matter, please contact the technical

contact listed below or the Regional Administrator of the appropriate regional

office.

Charles E. Rossi, Director

Division of Operational Events Assessment

Office of Nuclear Reactor Regulation

Roger Woodruff, NRR

(301) 492-7096 Attachments:

1. Farley 2 Temperature Data

2. Farley 2 ECCS

3. List of Recently Issued NRC Information Notices

• See previous Concurrence

OFC  :*EAB:NRR  :*EAB:NRR  :*C:EAB:NRR  :*D:DEST :XC:GCB :D:DOEA

NAME :RWoodruff* RLobel* :WLanning* :LShao* :CBerlinger .  :

DATE :1/11/88 :1/11/88 :1/12/88 :1/13/88 :1/15/88 :1L2//88 OFFICIAL RECORD COPY

3 Corrective action for this common-mode failure would include redesigning the

piping. instrumenting unisolable and adjacent portions of the piping to detect

cyclic or abnormal thermal stresses, instrumenting the ECCS manifold to detect

pressure resulting from valve leakage. or providing additional surveillance.

No specific action or written response is required by this information notice.

If you have any questions about this matter, please contact the Regional

Administrator of the appropriate regional office or this office.

Charles E. Rossi. Director

Division of Operational Events Assessment

Office of Nuclear Reactor Regulation

Roger Woodruff. NRR

(301) 492-7096 Attachments:

1. Farley 2 Temperature Data

2. Farley 2 ECCS

3. List of Recently Issued Information Notices

DISTRIBUTION

EAB R/F

WLANNING

RWOODRUFF R/F

RLOBEL

CROSSI

CBERLINGER

LSHAO

TECH:ED:

AThomas

/ /88

• See previous Concurrence

OFC :EAB:NRA :EAB:NRR :C:EAB:NRR :D:DEST :C:GCQ__ 4 < D:DOEA:

NAME :RWoodruff* RLobel* :WLanning* :LShao* :CBerlinger :CERossi  ::

DATE : / /88  : / /88  : / /88  : / /88 1/Ir78  : / /88 OFFICIAL RECORD COPY

I t- K-1d

3 Assurance that this common mode failure does not occur could be provided by

redesign of the piping, instrumenting unisolable and adjacent portions of the

piping to detect cyclic or abnormal thermal stresses, instrumenting the ECCS

manifold to detect pressure resulting from valve leakage, or providing

additional surveillance.

No specific action or written response is required by this information

notice. If you have any questions about this matter, please contact the

Regional Administrator of the appropriate regional office or this office.

Charles E. Rossi, Director

Division of Operational Events Assessment

Office of Nuclear Reactor Regulation

Roger Woodruff, NRR

(301) 492-7096 Attachments:

1. Farley 2 Temperature Data.

2. Farley 2 ECCS.

3. List of Recently Issued Information Notices.

DISTRIBUTION

EAB R/F

WLANNING

RWOODRUFF R/F

RLOBEL

CROSSI

CBERLINGER

LSHAO

TECH:EDa

AThomas V

/ //y/88 OFC :EAB yR :EAB:NRR: :D S :C:GCB MDUDEA:

NAME :RW o un :'db RLobel  : anni g :Lhao :CBerlinger :CERossi  ::

DATE : I/\/88  : I/l /88

• I/l /88 *1/13/88  : / /88  : / /88  :

OFFICIAL RECORD COPY

DATE: LmI6._l%

TO: RECORD SERVICES BRANCH

FROM: TI

CENTRAL FILES VERSION OF MASS MAILING ENCLOSED. NO FURTHER

DISTRIBUTION NECESSARY EXCEPT AS NOTED BELOW.

RETURN DOCUMENT TO