Information Notice 1990-68, Stress Corrosion Cracking of Reactor Coolant Pump Bolts

Stress Corrosion Cracking of Reactor Coolant Pump Bolts

ML031130215
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:	10/30/1990
From:	Rossi C Office of Nuclear Reactor Regulation
To:
References
IN-90-068, NUDOCS 9010240315
Download: ML031130215 (8)

UNITED STATES K--

NUCLEAR REGULATORY COMMISSION

OFFICE OF NUCLEAR REACTOR REGULATION

WASHINGTON, D.C. 20555 October 30, 1990

NRC INFORMATION NOTICE NO. 90-68: STRESS CORROSION CRACKING OF REACTOR

COOLANT PUMP BOLTS

Addressees

All holders of operating licenses or construction permits for pressurized water

reactors (PWRs).

Purpose

This information notice is intended to alert addressees of a significant event

which occurred at a foreign reactor. The event involves the use of a material

sensitive to intergranular stress corrosion cracking (IGSCC) in the fabrication

of the bolts fastening the turning vanes of the reactor coolant pumps. 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 do not constitute NRC

requirements; therefore, no specific action or written response is required.

Description of Circumstances

The U.S. Nuclear Regulatory Commission (NRC) has received information concerning

cracking of the bolts fastening the turning vanes of the reactor coolant pumps

at a foreign reactor plant. There are 23 bolts fastening the turning vanes in

each of three reactor coolant pumps. Five of these bolts had experienced stress

corrosion cracking. The bolts were made of a stainless steel all'y which is

designated by the American Society for Testing and Materials as A453 grade 660.

The material is commonly described commercially as alloy A-286. The reactor

coolant pumps are similar in design to those manufactured by the Westinghouse

Electric Company.

Considerable information has previously been available regarding the suscepti- bility of alloy A-286 to IGSCC. For example, licensees of U.S. reactors

designed by Babcock and Wilcox (B&W) have noted stress corrosion cracking of

bolts fabricated of alloy A-286. Specifically, bolts fastening the B&W reactor

internals, including the core barrel and lower thermal shield, were fabricated

of alloy A-286. Between 1981 and 1984, bolt cracking and indication of cracking

were documented at Oconee, Rancho Seco, Crystal River and Arkansas Unit 1. In

response, the B&W owners group formed a special task force to study the internal

bolts of the reactor vessel. This task force documented its conclusions in

BAW-1842, "The B&W Owners Group Evaluation of Internals Bolting Concerns in 177 FA Plants," August 1984. The task force concluded that bolts fabricated

9010240315 LA-

IN 90-68 October 30, 1990 of alloy A-286 are subject to IGSCC at peak stresses above 100 ksi. The

occurrence of IGSCC also appeared to be a function of chromium content, fabrication practice and environment. As a result of the task force findings, the design of the reactor internal bolts was modified at B&W plants to use

fastener materials that are less sensitive to IGSCC than alloy A-286-or to

reduce the maximum stress loadings of bolts fabricated of alloy A-286 to less

than 100 ksi.

In addition, the Brookhaven National Laboratory (BNL) performed an extensive

study of bolting which is documented in NUREG/CR-3604, "Bolting Applications,"

May 1984. The report discusses the direct relationship between loading and

IGSCC of bolts fabricated of alloy A-286. In this report, BNL recommended

that alloy A-286 not be used as a reactor structural material because of its

susceptibility to IGSCC.

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

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

technical contacts listed below or the appropriate NRR project manager.

_ *:a~rlesv NM , riector

E.

Division ofOperation-ar Events Assensment*-

Office of Nuclear Reactor Regulation

Technical Contacts: Clifford Sellers, NRR

(301) 492-0703 Walton Jensen, NRR

(301) 492-1157 Attachment: List of Recently Issued NRC Information Notices

Attachment 1 IN 90-68 October 30, 1990 LIST OF RECENTLY ISSUED

NRC INFORMATION NOTICES

Information Date of

Notice No. Subject Issuance Issued to

90-67 Potential Security Equipment 10/29/90 All holders of OLs

Weaknesses or CPs for

nuclear power

reactors and

Category I fuel

facilities.

90-66 Incomplete Draining and 10/25/90 All holders of OLs

Drying of Shipping Casks for nuclear

power reactors

and all registered

users of NRC

approved waste

shipping packages.

88-63, High Radiation Hazards 10/5/90 All holders of OLs

Supp. 1 4robimrria3'ated Incore or CPs for nuclear

Detectors and Cables power reactors.

90-65 Recent Orifice Plate 10/5/90 All holders of OLs

Problems or CPs for nuclear

power reactors.

90-64 Potential for Common-Mode 10/4/90 All holders of OLs

Failure Of High Pressure or CPs for pres- Safety Injection Pumps or surized-water

Release of Reactor Coolant reactors.

Outside Containment During

A Loss-Of-Coolant Accident

90-63 Management Attention to the 10/3/90 All fuel cycle

Establishment and Main- licensees possess- tenance of A Nuclear ing more than

Criticality Safety Program critical mass

quantities of

special nuclear

material.

OL = Operating License

CP = Construction Permit

IN 90-68 October 30, 1990 of alloy A-286 are subject to IGSCC at peak stresses above 100 ksi. The

occurrence of IGSCC also appeared to be a function of chromium content, fabrication practice and environment. As a result of the task force findings, the design of the reactor internal bolts was modified at B&W plants to use

fastener materials that are less sensitive to IGSCC than alloy A-286 or to

reduce the maximum stress loadings of bolts fabricated of alloy A-286 to less

than 100 ksi.

In addition, the Brookhaven National Laboratory (BNL) performed an extensive

study of bolting which is documented in NUREG/CR-3604, "Bolting Applications,"

May 1984. The report discusses the direct relationship between loading and

IGSCC of bolts fabricated of alloy A-286. In this report, BNL recommended

that alloy A-286 not be used as a reactor structural material because of its

susceptibility to IGSCC.

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

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

technical contacts listed below or the appropriate NRR project manager.

Odginal Signed by

Charles E. Rossi, Director Chades E.Rossi

Division of Operational Events Assessment

Office of Nuclear Reactor Regulation

Technical Contacts: Clifford Sellers, NRR

(301) 492-0703 Walton Jensen, NRR

(301) 492-1157 Attachment: List of Recently Issued NRC Information Notices

• SEE PREVIOUS CONCURRENCE

NRR:EAB NRR:EAB TECH ED GPA:IP NRR:EMCB

• WJensen *NPKadambi *KBurke *CSellers

08/01/90 08/13/90 07/27/90 08/21/90 08/10/90

NRR:EMCB NRR:DET NRR: EAB NRR:GCB

• CYCheng *JRichardson *PBaranowsky *CBerlinger

08/27/90 08/27/90 09/06/90 10/19/90 10/290

DOCUMENT NAME: IN 90-68

IN 90-XX

October XX, 1990 of alloy A-2&6 are subject to IGSCC at peak stresses above 100 ksl. The

occurrence of IGSCC also appeared to be a function of chromium content, fabrication practice and environment. As a result of the task force findings, the design of the reactor internal bolts was modified at B&W plants to use

fastener materials that are less sensitive to IGSCC than alloy A-286 or to

reduce the maximum stress loadings of bolts fabricated of alloy A-286 to less

than 100 ksi.

In addition, the Brookhaven national Laboratory (BNL) performed an extensive

study of bolting which is documented in NUREG/CP-3604, "Bolting Applications,"

May 1984. The report discusses the direct relationship between loading and

IGSCC of bolts fabricated of alloy A-286. In this report, BNL recommended

that alloy A-286 not be used as a reactor structural material because of its

susceptibility to IGSCC.

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

you have any questions about this matter, please contact one of the(tiO-

technical contacts listed below or the appropriate NRR project manager.

Charles E. Rossi, Director

Division of Operational Events Assessment

Office of Nuclear Reactor Regulation

Technical Contacts: Clifford Sellers, NRR

(301) 492-0703 Walton Jensen, NRR

(301) 492-1157 Attachment: List of Recently Issued NRC Information Notices

• SEE PdEVIOUS CONCURRENCE

NRR:EAE PRR:EAB TECH ED GPA:IP NRP:EHCB

• VJ1ensen *NPKadambi *KBurke *CSel lers

08/01/90 08/13/90 07/27/90 08/21/90 08/10/90

NRR:EMCE NPR:DET NPR:EAB N :GCE NRR:DOE,

• CYCheng *J~ichardson *P~aranowsky v Berlinger CRossi t

08/27/90 08/27/90 09/06/90 q ecWW 9 09/ /90

201(/l

DOCUIMENT NAME: INBOLT

IN 90-XX

July XX, 1990 materials that are

internal bolts was modified at B&W plants to use fastener the maximum stress

less sensitive to IGSCC than alloy A-286 or to reduce than 100 ksi.

loadings of bolts fabricated of alloy A-286 to less

an extensive study of bolting

The Brookhaven National Laboratory (BNL) performed "Bolting

for the NRC staff. This study is documented in NUREG/CR-3604, direct relationship between

Applications," May 1984. The report discusses the In this report, BNL

loading and IGSCC of bolts fabricated of alloy A-286. structural material

recommended that alloy A-286 not be used as a reactor

because of its susceptibility to IGSCC.

or written response. If

This information notice requires no specific action contact one of the the

you have any questions about this matter, please NRR project manager.

technical contacts listed below or the appropriate

Charles E. Rossi, Director

Division of Operational Events Assessment

Office of Nuclear Reactor Regulation

Technical Contacts: Clifford Sellers, NRR

(301) 492-0703 Walton Jensen, NRR

(301) 492-1157 Attachment: List of Recently Issued NRC Information Notices

DISTRIBUTION:

CRossi DOEA r/f

WJensen EAB r/f

NPKadambi Central Files

CSellers JRichardson

PBaranowsky CBerlinger

V If

• SEE PREVIOUS CONCURRENCE -XGPA: P -rNRR:EMCB c<;

NRR:EAB NRR:EAB *TECH ED

• NPKadambi KBurke CSellers

• WJensen 08/10/90

08/01/90 08/13/90 07/27/90 08/21/90

NRR:DEf4 NRRffM NRR:DOEA

NRR:E CRossi

CYCh d JRichardo P aranowsky

o8.7 o 08'/ IC 6/90

DOCUMENT NAME: INBOLT

IN 90-XX

July XX, 1 0

Page 2 o 2 fastener materials hat are

internal bolts was modified at B&W plants to usereduce the maximum tress

less sensitive to IGSCC than alloy A-286 or to than 100 ksi

loadings of bolts fabricated of alloy A-286 to less

an extensi study of bolting

The Brookhaven National Laboratory (BNL) performed , 'Bolting

for the NRC staff. This study is documented in NUREG/CR-36 elationship between

Applications,u May 1984. The report discusses the direct In ihs report, BNL

loading and IGSCC of bolts fabricated of alloy A-286. s ructural material

recommended that alloy A-286 not be used as a reactor

because of its susceptibility to IGSCC.

written response. If

This information notice requires no specific actio or one of the the

ntact

you have any questions about this matter, please project manager.

technical contacts listed below or the appropria NRR

Charles E. ossi, Director

Division f Operational Events Assessment

Office Nuclear Reactor Regulation

Technical Contacts: Clifford Sellers, R

(301) 492-0703 Walton Jensen, RR

(301) 492-11 Attachment: List of Recently ssued NRC Information Notices

DISTRIBUTION:

CRossi DOEA /f

WJensen EAB f

NPKadambi C tral Files

CSellers Richardson

PBaranowsky Ceerlginger )C, 1+ v

RR:EAB TECH E GPA:IP NRR:EMCB

NRRR:

KBurke CSellers DA CJ (

W NPKadambi .4NA//

O-/

90 07/i/90 &z4 /90 GR/ /90

00///

NRR: T NRR:EAB NRR:GCB NRR:DOEA

JRi ardson PBaranowsky CBerlinger CRossi

07 /90 07/ /90 07/ /90

DOCUMENT NAME: INBOLT