ML20084K269

Interim Deficiency Rept Re Cracked & Broken Piston Rods in Brown-Boveri Electric Type 5HK Circuit Breakers.Recommends Insp for Cracked or Broken Puffer Piston Rods at Normal Maint Intervals

ML20084K269
Person / Time
Site:	Oconee, Fermi, Midland, 05000000
Issue date:	11/29/1983
From:	Rhoads E BBC BROWN BOVERI, INC. (FORMERLY BROWN BOVERI CORP.
To:	Baer R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE)
Shared Package
ML20084K247	List: ML20084K244 ML20084K269
References
IEIN-83-84, NUDOCS 8405110160
Download: ML20084K269 (2)

Text

~

1 -

Brown Boveri Electric, Inc. -

i Manufacturer of l-T-E Electrical Power Equipment

~

-' A 5 3 6 8

===-

145475  :

November 29, 1983 .

. I

~

t Mr. Robert L. Baer, Chief

' Engineering and Generic Comenmfcations Branch }

j  ;

Division of Emergency Preparedness >

j and Engineering Response - j Office of Inspection and Enforcement i

United States Nuclear Regulatory  !

Commission -

Washington, D. C. 20555

Subject:

Cracked and Broken Piston Bods in Brown Boveri Electric. f (yormerly I-T-E) Type SEK Circuit Breakers -

/!

Dear Mr. Baer:

This letter is in iresponse to your' letter of November 23, 1983 which enclosed  !

a Draft NRC 1E Information Notice pertaining to the subject. l

~

\

• Since the submitt'a l 'of the BBE Interim Report on this subject dated October. l 3,1983, some of the broken puffer piston rods were subjected to a micro- i structural analysis wherein the samples were microtomed in the area of the j l failure to enhance the crystaline structure of them for microscopic analysis.  ;

l This analysis revealed that there were some material voids in the broken area  !

l which suggested that there were venting problems with the tool used to sold  :

the puffer piston rod. These voids could also be caused by trapped moisture  !

during the molding process which would weaken the part. Another broken sample j revealed a nonhomogeneity of the crystaline structure which would cause local '

areas of high stress which could result in breakage. The most likely cause?  !

, of'this problem is a non-uniform tool temperature, which was caused by ope 9-/

' ating the tool while it was in the state of initial heat up for molding clie j

part. The few random problems that have been experienced to date for the l most part could be attributed to problems in processing the material by the -

vendor. The fact that failures have been experienced in very few and random areas reinforces this hypothesis. .

3 i

.. i The failed parts have been limited to those made with the material identified - l as Zytel.101 (Nylon 6/6). Since 1980, the parts have been manufactured with a toughened and reinforced material identified as Nylafil. No problems have been reported on the parts manufactured with the Nylafil material.

Recently some puffer piston assemblies were recovered from the Oconee Nuclear Station at Duke Power. Examination of these parts from circuit breakers manufactured in 1969 revealed no defects whatsoever. It appears that the

- l 8405110160 840330 PDR ADOCK 05000329 S PDR Suneshamar Systones o6seien i Sedag Heine, PA 19477 *(2151 828 7400  ;

l

. . . _ . . . . . _ _ . - . . . . . . . . . . . _ . . . . _ . .. . ....- .t Brown Boveri Electric, Inc.

l h-

- Mr. Bibert L. Beer -

i 4 5@aS c 475 November 29, 1983 .

l Page 2 l

l l

t relatively few processing problems that were experienced are random in nature.'  !

It has also been determined that although some parts will crack, they will not necessarily fail. l Some cracked parts returned from Detroit Edison (Farmi 2) I were of cracks. subjected to an endurance test of 1,200 operations without any propagation (

5  !

t The actual number of failed puffer piston push rods (broken) that have been I reported is less than twenty (20). Although others have been reported as being  !

cracked, and the parts should be replaced, they are not considered failures.  !

The total number of puffer piston assemblies installed in 5HK circuit breakers since 1968 is over 75,000. l' Based on the test result's and other information available at this time, the BBE ,

recommendation is to inspect for cracked or broken puffer piston rods at normal  !

maintenance intervals and to replace the puffer piston assembly if this condi-tion is found. .

lr r

In the Draft II Information Notice, the second paragraph under " Description of  !

Circumstances" is a correct statement in that spara puffer piston assemblies '

were found to be defective in receiving inspection at the Fermi plant and were returned to BBE. The parts were determined to be defective becausk of shipping {

l damage and ,other concerns which were not related to cracking or breakage of the l puffer piston push rods. As prescated, this infers that BBE is having similar l problems with the parts currently being.used and this is not the case. j i

Enclosed is a list of SEK circuit breakers that are being used in Class 1E i applications at nuclear power plants. The circuit breakers manufactured after 1980 have puffer piston push rods made with the Nylafil material and there is [

l no. reason to suspect that these will be subject to cracking or breakage. In-  ;

spection of circuit breakers with manufacturing dates of 1981 or later for '

cracking or breakage should not be necessary.

~ m

.Z&~4 E. W. IBOADS  :

Manager Quality Assurance r

( EWE /ja I i

r Enclosure

[

cc: D. D. Duvall

• r

\

C. E. re k.1 '

_ W. E. Laubach t W. Laudan - NRC ,

L. E. Schmidt t A. E. Stringfellow

• 'l i

. (

~

.r 145475  !

SSINS No.: 6835 IN 83.84 l'45368 UNITED STATES l NUCLEAR REGULATORY COMMISSION l OFFICE OF INSPECTION AND ENFORCEMENT  !

WASHINGTON, D.C. 20555 ,

f/ . December 30, 1983 (

t i  !

IE INFORMATION NOTICE NO. 83-84:'

CRACKED AND BROKEN PISTON RODS IN BROWN ~l B0VERY ELECTRIC TYPE SHK BREAKERS '

l Addressees: l l

All holders of a nuclear power reactor operating license (OL) or construction  !

permit (CP).

Purpose:

.l t

This information notice is provided.as n'otification of a potentially significant [

problem pertaining to Brown Bovery Electric (BBE) type SHK 250/350, 1200/2000 t ampere circuit breakers. Addressees'are expected to review the information for  !

applicability to their facilities. No specific action or response i.s required I at this. time. ,

Description of Circumstances:  ;

i On March 21, 1983, Detroit Edison notified the NRC under the provisions of 10 i CFR 50.55(e) of a potential problem with BBE 5HK 4160 volt breaker puffer i piston rods at the Fermi 2 nuclear plant. The puffer piston connecting rods I

developed cracks and one shaft failed. The inanufacturer's part number is 193642B. The cracking and failure occurred at the hole in the shaft where the

-linkage is connected by a pin. These breakers were manufactured in 1973. A i total of five breakers were affected at the Fermi 2 site. l l

. ~ On September 12, 1983, Detroit Edison advised an NRC inspector that during a [

receiving inspection at the Fermi plant, spare puffer piston connecting rods were found to be defective. They were all returned to the vendor. BBE informed j l the NRC on November 29, 1983 that the damage tS these puffer piston connecting  !

l- rods were a result of shipping problems and were not related to the manufacturing  ;

!; process. .

l i

On October 12, 1983, BBE provided the NRC with an' Interim Report pertaining to  ;

.the SHK breaker puffer piston. connecting rod problem. The report indicated that at a Southern California Edison (SCE) non-nuclear plant eight puffer  !

l piston connecting rods were found to be broken. -

i l Puffer pistons in the BBE SHK breakers perform two functions. For low current -

l l interruptions the puffer is needed to assist the magnetic forces to move the i i

h

==

IN 83-84 145368 I45475 $*6f [.

l'8 arc into the interrupting chamber. The arc may not be extinguished if the puffer piston fatis.  ;

The other function performed by the puffer piston is to '

provide a pneumatic cushion which reduces the shock forces imposed on the mechanism and current carrying parts upon opening. A failure of the puffer i piston could reduce the number of operations before maintenance on the breaker would be necessary.  !

BBE indicated that no breaker failed because of a broken puffer piston rod, however, the breaker's capability to interrupt at low current may be impaired.

BBE subjected broken piston rods to failure analysis including microscopic l l

analysis of the failed area and found that failed parts were limited to those  !

made with the material identified as Zytel 101 (Nylon 6/6). Since 1980, the l

parts have been manufactured with a toughened and reinforced material called "Nylatil." No problems have been reported on Nylatil material parts.

l Based on the test results and presently available information, BBE recommends inspecting for cracked or broken puffer.pf ston rods at normal maintenance l intervals and replacing the puffer piston assembly if this condition is found.

It should be noted that the nozzle of the puffer piston must be removed to inspect the rod properly.

• l Attached is a list provided by BBE of SHK circuit breakers that they supplied i for use in Class 1E applications at nuclear power plants, and which may be '

affected. Since breakers can also be obtained from intermediate sources, the list may not be complete. It is suggested that licensees evaluate their cquipment lists to determine if BBE 5HK breakers are used in safety-related cpplications in their plant. Inspection of circuit breakers with manufacturing ,

dates of 1981 or later for cracking or breakage of puffer piston rods should not be necessary.

If.you have any questions regarding this' matter, please contact the Regional Admittistrator of the appropriate NRC Regional Office, or this Office.

//

01~Ak b award L. Jordan irect r DivisionofEmer[gencyPreparedness I and Engineering Response .

Office of Inspection and Enforcement Technical

Contact:

W. Laudan, IE  !;

(301) 492-9759 6 Attachments: '

1. List of SHK Breake'r Customers

2. List of Recently Issued IE Information Notices i

i

, . i

. s -

! l45368 Attachment 1 l 14547,a in 83-84 December 30, 1983 Page 1 of 3 I l

88E TYPE 5HK BREAKER CUSTOMERS l

9 CUSTOMER 88E SALES ORDER DATE OF MANUFACTURE  !

i I

. CEI' -

t Perry 1&2 51958 - 8/78, 9/78 l 10/78 ,

t CFE '

Laguna Verde 53462 11/74 - 1/80 i t  !

l CP&L -

l Brunswick 1 .54792 10/81 l

Brunswick 2 47219 11/71 - 8/72 l 49839 3/74 - 3/79 l Cincinnati G&E Zimmer 51828 6/77 - 11/77 [

Commonwealth Edison LaSalle County 1&2 50080 10/75 - 12/75'  !

526.12 4/78, 5/78  !

l Zion 1&2 45122 5/70 - 2/71  !

t .

Consumers Power i l Midland 1&2 50382 4/75 - 9/75 l 9/75'- 6/76

' l 8/75 - 9/75  !

Detroit Edison l j, Fermi 2

~

47196 12/73 - 9/74 l l-Duke , ,

. Catawba 1 & 2 50465' 4/78 - 4/79  ;

McGuire 1 & 2 48560 9/72 - 11/74  ;

Oconee 3 44349 8/69 - 8/71 - I Duquesne Light Co.  !

Beaver Valley 1&2 46690 8/71 - 8/78 l Florida Power Corp .

Crystal River 3 46256 11/70 f Georgia Power Company -

Vogtle 1 51903 9/81 - 3/82 l Vogtle 2 51904 , 7/81 - 2/83 l

I Attachment 1 IN 83-84 145475 December 30. 1983 Page 2 of 3 145368 BBE TYPE SHK BREAKER CUSTOMERS CUSTOMER BBE SALES ORDER DATE OF MANUFACTURE l

l Gulf States Utilities River Bend 1&2 51126 11/80 - 3/83 )

51128 10/80 - 4/82 Indiana Michigan Electric Co.

Cook 1 44322 8/71 - 3/72 Cook 2 53372 5/79 Mississippi Power & Light Grand Gulf 1&2 50469 1/76 - 5/77 l Northern States Power

! Prairie Island 1&2 44477 2/70 - 1C/71 l

! PE

! Limerick 1&2 47651 3/77 - 5/77

. PSE&G Hope Creek 1&2 52260 10/79 - 1/80 PSI Marole Hill 2 52661 11/80 - 8/82 PSNH Seabrook 1&2 50750 1/77 - 8/77 Portland General Electric Trojan 47354 2/73

,. Sacramento Municipal Utility l . District l Rancho Seco 1 ,

45966 5/71 South Texas Project 1 52769 10/78- 's Project 2 52914 5/79 - 12/79 i Southern California Edison <

San Onofre 2&3 50395 ,

3/76, 4/76 Taiwan Kuo Sheng/ Unit 1&2 50735 5/77 - 12/76, 11/75 - 12/75, 3/76 l

I

. l I45473 Attachment r45368 IN 83-84 oecember 30, 1983 -

LIST OF RECENTLY ISSUED i IE INFORMATION NOTICES Information Date of i

) Notice No. Subject Issue Issued to i I

83-83 Use of Portable' Radio 12/19/83 All power reactor .

, Transmitters Inside Nuclear facilities holding  :

Power Plants an OL or CP -!

(

83-82 Failure of Safety / Relief 12/16/83 All power reactor  !

Valves to Open at BWR - facilities holding [

Final Report an OL or CP '

83-81 Entry Into High Radiation 12/7/83 All licensees autho- I l Areas From Areas Which Are rized to use portable  !

l Not Under Direct Surveillance radiography devices t

+

in radiography (

j programs i l

t i 83-80 Use of Specialized " Stiff" 11/23/83 All power reactor Pipe Clamps facilities holding l

an OL or CP; NSSS 1 and AEs  !

83-79 Apparently Improper Use'of 11/23/83 All power reactor Components in Safety-Related facilities holding '

Systems an OL or CP 83-78 Apparent Improper Modifica- 11/17/83 All power reactor i tion of a Component Affect- facilities holding l

. ing Plant Safety an OL or CP {

83-77 Air / Gas Entrainme*nt Events 11/14/83 All power reactor Resulting in System Failures facilities holding an OL or CP i

83-76 Reactor Trip Breaker Malfunc- 11/2/83 All power reactor tions (Undervoltage Trip facilities holding Devices on GE Type AK-2-25) an OL or CP 83-75 Improper Control , Rod Mani- 11/03/83 All power reactor ,

pulation facilities holding  ;

an OL or CP .l, I

s  !

i OL = Operating License l CP = Construction Permit i

?

?

..~, '

I45475 Attachment 1 I45368 in 83-84 December'30, 1983 Page 3 of 3 BBE TYPE SHK BREAKER CUSTOMERS

( CUSTOMER BBESALESdRDER DATE OF MANUFACTURE VEPCO North Anna 2 48709 9/76, 10/76 WPPSS WNP 1&2 51659 3/78 - 1/79

. e

. \

I. .

9 f

1 i

, _ _ . _ _ _ _ - . _ . _ _ _ _ _ . . . . - . _ _ _ . . _ _ _ . . _ . . ~ _ _ , _ _ _ _ . _ _ _ _ _ _ . _ _ _ . _ _ _ _ _ _ _ . _ . _ _ _

T 4,

lll l{ p 12/1/83 l .

Silk BREAKERS

• Customer BBE Sales Order Date of Mfar.

CP&L/ Brunswick 2

• 47219 11/71 - 8/72 __

i Brunswick 1 54792 10/81 .n- t

, Brunswick 2 . 49839 3/74 - 3/79 ui i co I

Cincinnati G & E/Zimmer 51828 6/77 - 11/77 m co I CEI/ Perry 1 & 2 51958 8/78 [

9/78 __  ;

10/78 ,  !

C.rt s l

Commonwealth Edison / Zion 1 & 2 45122 5/70 - 2/71 .e- -

i

/LaSalle County 1 & 2 50080 10/75 - 12/75 .N  !

! /LaSalle County 1 & 2 52612 4/78, 5/78 ui ,

! i l

i Consumers Power / Midland 1 & 2 50382 4/75 - 9/75 9/75 5/76 li j 8/75 - 9/75 Detroit' Edison / Fermi 2 47196 12/73 - 9/74 Duke /Oconee 3 44349 8/69 - 8/71  !

/McCuAre 1 & 2 48560 9/72 - 11/74 i i

/ Catawba.1 & 2 50465 5 4/78 - 4/79 I i Duquesne Light Co./ Beaver Valley 1 & 2 l 46690 8/71 - 8/7b l

l FloridaPowerCorpICrystalRiver3 46256 11/70 Georgia Power company /Vogtle 1 51903 9/81 - 3/82

{

/Vogtle 2 . 51904 -

7/81 - 2/83 ,

i Gulf States Utilities / River Bend 1 & 2 51126 11/80 - 3/83 i

} 51128 10/80 - 4/82 i l I j Indiana Hichigan Electric

• Co./ Cook 1 44322 8/71 - 3/72 4

/ Cook 2 53372 5/79 .

1 i I

-l l l l 12/1/83 { l' .

.3

~

5HK Brc:ksrc - .

l. . Page 2 [.$. !

i Customer BBE Sales Order, Date of Mfar. ,

Hississippi Power & Light / Grand Gulf 1 & 2 50469 1/76 - 5/77 ,

Northern States Power / Prairie Island 1 & 2 44477 2/70 - 10/71 l P.E./ Limerick 1 & 2 47651 3/77 - 5/77 E*

U1 Portland General Electric / Trojan 4735'4 2/73 to  !

m 52661 11/80 - 8/82 CD

• PSI / Marble Hill 2 PSNH/Seabrook 1 & 2 50750 1/77 - 8/77 I

) PSE&C/ Hope Creek 1 & 2 52260 10/79 - 1/80 .

l Sacramento Municipal Utility District /  !

I Rancho Seco 1 45966 5/71 us ,

Southern California Edison / .a-l i San Onofre 2 & 3 50395 3/76, 4/76 N ,

u, t South Texas / Project 1 52769 10/78 ,

! / Project 2 52914 5/79 - 12/79 1 .

-' 9/76, 10/76 VEP Company / North Anna 2 48709 l

i WPPSS/WNP 1 & 4 51659 3/78 - 1/79 i Taiwan /Kuo Sheng/ Unit 1 & 2 50735 5/77 - 12/76 &.

11/75 - 12/75 &

1 3/76 i * -

CFE/ Laguna Verde 53462 11/74 - 1/80 i

I .

- - - . . . . . -_