Information Notice 1989-01, Valve Body Erosion

Valve Body Erosion

ML031180473
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:	01/04/1989
From:	Rossi C Office of Nuclear Reactor Regulation
To:
References
IN-89-001, NUDOCS 8812300119
Download: ML031180473 (4)

-s UNITED STATES NUCLEAR REGULATORY

COMMISSION

OFFICE OF NUCLEAR REACTOR REGULATION

WASHINGTON, D.C. 20555 January 4, 1989 NRC INFORMATION

NOTICE NO. 89-01: VALVE BODY EROSION

Addressees

All holders of operating

licenses or construction

permits for nuclear power reactors.

Purpose

This information

notice is provided to alert recipients

to a potential

generic problem pertaining

to erosion found in carbon steel valve bodies in safety-related systems. It is expected that recipients

will review the information

for applicability

to their facilities

and consider actions, if appropriate, to preclude a similar problem. However, suggestions

contained

in this notice do not constitute

NRC requirements;

therefore, no specific action or written response is required.Description

of Circumstances:

During the Brunswick

Steam Electric Plant, Unit 1 refueling

outage, inspections

performed

on December 13, 1988, indicated

areas of significant

but localized erosion on the internal surfaces of several carbon steel valve bodies. The affected safety-related

globe valves were the 24-inch RHR/LPCI system injection and 16-inch suppression

pool isolation

valves. Subsequent

ultrasonic

testing of identical

valves on Unit 2, which was operating

at power, indicated

similar erosion. Additional

valves used for throttling

service (such as high pressure coolant injection)

have indicated

less erosion possibly due to the fact that they have seen less service.Discussion:

The valve bodies that have been ultrasonically

tested indicate that the minimum measured wall thicknesses

are approaching

the minimum code allowable

thicknesses.

Minimum Wall Thickness

-inches Valve Unit 1 Unit 2 Code Allowable

Nominal RHR/LPCI Train A 2.7 2.6 1.47 4 RHR/LPCI Train B 1.7 1.9 1.47 4 Suppression

Pool Train A N/A 0.8 0.49 2 Suppression

PmT I Train B 0.7 0.6 0.49 2 7 881230119 IN 89-01 January 4, 1989 The obvious safety concern is that continued

operation

without weld repair or replacement

could lead to rupture of safety-related

valve bodies.The root cause assessment

of this erosion phenomenon

has not been finalized.

The licensee currently

believes that the erosion may have resulted from throttling

the globe valves below their design flow range. Excessive

throttling

can promote cavitation

which enhances internal valve body erosion.A similar problem appears to be occurring

at Hatch Unit 1. On November 17, 1988, a severe banging noise was heard coming from the line which connects the "B" loop of the RHR system to the Condensate

Storage and Transfer System. At the time, the "B" loop of RHR was in the shutdown cooling mode. Further investigation

revealed that the cause of the banging was cavitation

of the 24-inch RHR/LPCI system injection

globe valve. The Unit 1 shift supervisor

took action to alleviate

the problem by repositioning

the valve to increase the flow rate, thus reducing the cavitation.

Examination

of the valve body wall thickness has not been reported to date.Past Related Generic Communications:

NRC Information

Notice No. 88-17, "Summary of Responses

to NRC Bulletin 87-01,'Thinning

of Pipe Walls In Nuclear Power Plants'," dated April 22, 1988, provides additional

information

on erosion downstream

of turbine-driven

reactor feedwater pump minimum-flow

control valves. LaSalle Unit 1 experienced

through-wall

ero-sin in th-e-expa-fde-rdire-tly

dt-ons-tream-of-the-cone-shaped1sc- in-the minimum-flow

control valve.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.bar1_ esE.,irector

'Division of Operational

Events Assessment

Office of Nuclear Reactor Regulation

Technical

Contact: Frank J. Witt, NRR (301) 492-0823 Attachment:

List of Recently Issued NRC Information

Notices

Attachment

IN 89-01 January 4, 1989 Page'1 of 1 LIST OF RECENTLY ISSUED NRC INFORMATION

NOTICES Information

Date of Notice No. Subject Issuance Issued to 88-46, Supp. 2 88-101 88-100 88-99 Licensee Report of Defective Refurbished

Circuit Breakers Shipment of Contaminated

Equipment

between Nuclear Power Stations Memorandum

of Understanding

between NRC and OSHA Relating to NRC-licensed

Facilities

(53 FR 43950, October 31, 1988)Detection

and Monitoring

of Sudden and/or Rapidly Increasing

Primary-to- Secondary

Leakage 12/30/88 12/28/88 12/23/88 12/20/88 All holders of OLs or CPs for nuclear power reactors.All holders of OLs or CPs for nuclear power reactors.All major nuclear materials

licensees and utilities

holding CPs and OLs.All holders of OLs or CPs for PWRs.88-98 88-97 88-96 88-95 88-94 88-93 Electrical

Relay Degradation

Caused by Oxidation

of Contact Surfaces Potentially

Substandard

Valve Replacement

Parts Electrical

Shock Fatalities

at Nuclear Power Plants Inadequate

Procurement

Requirements

Imposed by Licensees

on Vendors Potentially

Undersiled

Valve Actuators Teletherapy

Events 12/19/88 12/16/88 12/14/88 12/8/88 12/2/88 12/2/88 All holders of OLs or CPs for nuclear power reactors.All holders of OLs or CPs for nuclear power reactors.All holders of OLs or CPs for nuclear power reactors.All holders of OLs or CPs for nuclear power reactors.All holders of OLs or CPs for nuclear power reactors.All NRC medical licensees.

OL = Operating

License CP = Construction

Permit

IN 89-01 January 4, 1989 The obvious safety concern is that continued

operation

without weld repair or replacement

could lead to rupture of safety-related

valve bodies.The root cause assessment

of this erosion phenomenon

has not been finalized.

The licensee currently

believes that the erosion may have resulted from throttling

the globe valves below their design flow range. Excessive

throttling

can promote cavitation

which enhances internal valve body erosion.A similar problem appears to be occurring

at Hatch Unit 1. On November 17, 1988, a severe banging noise was heard coming from the line which connects the "B" loop of the RHR system to the Condensate

Storage and Transfer System. At the time, the "B" loop of RHR was in the shutdown cooling mode. Further investigation

revealed that the cause of the banging was cavitation

of the 24-inch RHR/LPCI system injection

globe valve. The Unit 1 shift supervisor

took action to alleviate

the problem by repositioning

the valve to increase the flow rate, thus reducing the cavitation.

Examination

of the valve body wall thickness has not been reported to date.Past Related Generic Communications:

NRC Information

Notice No. 88-17, "Summary of Responses

to NRC Bulletin 87-01,'Thinning

of Pipe Walls In Nuclear Power Plants'," dated April 22, 1988, provides additional

information

on erosion downstream

of turbine-driven

reactor feedwater pump minimum-flow

control valves. LaSalle Unit 1 experienced

through-wall

erosion in the expander directly downstream

of the cone-shaped

disc in the minimum-flow

control valve.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

Technical

Contact: Frank J. Witt, NRR (301) 492-0823 Attachment:

List of Recently Issued NRC Information

Notices ECEB:DEST:NRR

D:DEST:NRR

C:O CB:DOEA:NRR

FJWitt LShao CHBerlinger

CERossi 12/ /88 12/ /88 12/3o/88 12Wg88 1~Z, f A. 5