ML19347D995

Forwards Response to IE Bulletin 81-01, Surveillance of Mechanical Snubbers. No Inc Mechanical Snubbers Installed on safety-related Sys or in Storage

ML19347D995
Person / Time
Site:	Farley
Issue date:	04/06/1981
From:	Clayton F ALABAMA POWER CO.
To:	James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
References
IEB-81-1, NUDOCS 8104140590
Download: ML19347D995 (9)

Text

1 McMif"j Address

+T Alabama Power Comhny

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a 600 North 18th Street i Post Office Box 2641 Birmingham, Al:bam335291 Telephone 205 783-6081 )

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U or V President Flintridge Building Alabama Power l

April 6, 1981 Docket N 0-348 -

\' 4 Docket No 0-364 g '

b aE W FED -2 Mr. James P. O'Reilly 2 Apg y 3 y00lb U. S. Nuclear Regulatory Commission BJ Region II gDM_

y 101 Marietta Street, N. W. y -

Suite 3100 .p Atlanta, Georgia 30303 w

Dear Mr. O'Reilly:

In response to I. E.Bulletin 81-01, " Surveillance of Mechanical Snubbers", dated January 27, 1981, Alabama Power Company submits the enclosed response for Units 1 and 2 of Farley Nuclear Plant.

Alabama Power Company expended approximately 2620 manhours in the review and' preparation of the reports required by this bulletin.

In addition, an estimated 48 manhours were expended on the corrective actions required. For Farley Nuclear Plant - Unit 2 no manpower was expended to specifically address the requirements of this bulletin because the actions required by the bulletin had been performed previously as a portion of pre-operational testing.

If there are any questions, please advise.

Very truly yours, h

hhNw F. L. Claytong Jr.

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WGW:bs Enclosures cc: Mr. R. A. Thomas SWORNTOANDSUBSCgIBED Mr. G. F. Trowbridge BEFORE ME THIS I DAY Mr. L. L. Kintner Mr. E. A. Reeves 0F [MM ,1981 "S$$"f!"*Y"d M Notary 84 M .

PgE11c Washington, D.C.

Mr. M. D. Hunt My Conchsion Expires: b I&E Region II 810.41.4 offp- ,

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l ENCLOSURE I RESPONSE TO IE3 81-01 JOSEPH M. FARLEY NUCLEAR PLANT - UNIT 1 REQUESTED ACTION

1. All normally accessible INC mechanical snubbers installed on safety-related systems or in storage shall be visually examined and tested.

RESPONSE

Not Applicable. There are no INC mechanical snubbers installed on safety-related systems or in storage at Farley Nuclear Plant - Unit 1.

REQUESTED ACTION

2. Visually examine and test all inaccessible INC mechanical snubbers installed on safety-related systems.

RESPONSE

Not Applicable. There are no INC mechanical snubbers

-- installed on safety-related systems at Farley Nuclear Plant - Unit 1.

1 REQUESTED ACTION ,

3. Provide a schedule for an inspection program covering mechanical snubbers produced by other manufacturers. As a minimum, this inspection program shall:

a. Include all snubbers installed on safety-related systems;

b. Include the visual examination and manual test described in Iten la for all snubbers;

c. Snubbers which have been examined and tested in a manner comparable to Item 3b above within the last twelve months may be exempted;

d. Require the corrective action and evaluations described in Items ld and 2d; and

e. Be completed prior to the completion of the next refueling outage. Plants which are currently in a refueling outage should perform the visual examination and manual tests of inaccessible mechanical snubbers before resumption of operations unless some .other basis for assurance of snubber operability is provided to the NRC.

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RESPONSE

Since Farley Nuclear Plant - Unit 1 was in a refueling outage when IEB 81-01 was issued, the visual examination and manual  ;

test described in Item la of IEB 81-01 were perfonned on all installed safety-related mechanical snubbers before beginning

_ the Unit 1 return to power. All corrective actions and evaluations were completed prior to Unit I returning to power.

REQUESTED ACTION

4. Submit a report of the results of the insnections, testing i and evaluation requested in Item 1 to NRC within 45 days of  ;

the issuance date of this bulletin. Report the results of the inspections, testing and evaluation requested in Item 2 within 30 days after the inspection and testing have been .

completed. The response to Item 3 shall be submitted within '

60 uays of the issuance date of this Bulletin. The results of the inspections perfonned for Item 3 shall be submitted within 60 days after the completion of the inspection.

The reports shall contain the following: .

, a. A description of the visual examinations and tests performed.

b. Number of snubbers examined and tested. Grouping by manu-facturer name, model number, and size is acceptable.

c. Number of failures identified; manufacturer name, model number, size, mode of failure, cause of failure, corrective action, snubber location, effect of failure on plant and system safety, and justification for continuing or resuming operation.

d. The above information shall also be provided for the snubbers exempted by Items 1c, 2c, and 3c.

RESPONSE TO Item 4a Visual examinations and tests were performed in accordance with .

the Farley Nuclear Plant Mechanical Snubber Inspection and Functional Test Procedure which included the following actions:

(1) Visual inspection of each snubber for structural damage, corrosion, bending, interferences with adjacent components, and integrity of fasteners.

(2) Verification that each snubber is not at the end of its extended or retracted limits.

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- '- Enclosure 1 Page 3 l ,

(3) Rotation of each snubber about its axis by hand to verify freedom of movement at its pivot points.

(4) Visual inspection of the end connections of each i snubber for damage, corrosion, sufficient thread engagement and tightness of fasteners.  ;

(5) Performance of a functional test by disconnecting each snubber at one end and stroking over the full range of travel in both compression and tension.

Unsatisfactory results were recorded such as, irregular l travel, inability to stroke over full range or indications of internal mechanical interferences.

(6) If the visual inspection or functional test was  !

unacceptable, the snubber was repaired or replaced i as necessary. -

l RESPONSE TO Item 4b ,

A total of 215 safety-related mechanical snubbers were inspected.

All snubbers were manufactured by Pacific Scientific. The number of snubbers tested, grouped by model, are as follows:

PSA-1/4 PSA-1/2 PSA-1 PSA-3 TOTAL 170 16  ; 23 6 21 5 RESPONSE TO Item 4c As shown in the table below, eight (8) snubbers failed the functional ,

test. They were mechanically locked up and would not stroke. All '

eight snubbers are the smallest size used in the Plant and were located on small (2 inch diameter or less) pipe. These snubbers could have been damaged during installation or when work was being

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conducted in the area of the snubber. No snubber damage was considered to be attributed to Plant or system operation. The eight snubbers were replaced and the systems returned to operable status. As an additional margin of safety, the portion of the piping system on which these snubbers were installed was visually inspected to l determine if the locked-up snubbers had caused any deformation or i overstressing. No indications of overstressing or deformation -

l were found.

HANGER MARK NO. MODEL NO./ SIZE LOCATION SS-1992 PSA-1/4 CTMT Bldg.

SS-2024 PSA-1/4 CTMT Bldg.

SS-2990 PSA-1/4 CTMT Bldg.

SS-4168 PSA-1/4 CTMT Bldg.

SS-4300 PSA-1/4 CTMT Bldg.

i SS-4434 PSA-1/4 CTMT Bldg.

l SS-5133 PSA-1/4 AUX. Bldg.

j. FT-426 PSA-1/4 CTMT B1dg.

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= . : .- . _. -

. *. Enclosure 1 Paga 4 RESPONSE TO Item 4d Not Applicable. Prior to the inspection / testing performed in response to this bulletin, no safety-related mechanical snubbers had been tested within the last twelve months.

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l ENCLOSURE II RESPONSE TO IEB 81-01 i JOSEPH M. FARLEY NUCLEAR PLANT - UNIT 2 REQUESTED ACTION

1. All normally accessible INC mechanical snubbers installed on safety-related systems or in storage shall be visually examined and tested.

RESPONSE

.Not Applicable. There are no INC mechanical snubbers installed on safety-related systems or in storage at Farley Nuclear Plant - Unit 2. .

REQUESTED ACTION i

2. Visually examine and test all inaccessible INC mechanical snubbers installed on safety-related systems.

RESPONSE  !

Not Applicable. There are no INC mechanical snubbers installed on safety-related systems at Farley Nuclear Plant - Unit 2.  ;

i REQUESTED ACTION

3. Provide a schedule for an inspection program covering mechanical snubbers produced by other manufacturers. As a minimum, this inspection program shall:

a. Include all snubbers installed on safety-related systems;

b. Include the visual examination and manual test described in Item la for all snubbers;

c. Snubbers which have been examined and tested in a manner comparable to Item 3b above within the last twelve months may be exempted; -

d. Require the corrective action and evaluations described in Items ld and 2d; and

e. Be completed prior to the completion of the next refueling outage. Plants which are currently in a refueling outage should perform the visual examination and manual tests of inaccessible mechanical snubbers before resumption of operations unless some other basis for assurance of snubber operability is provided to the NRC. l 4

Enc 1:sure II -

Page 2

RESPONSE

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All mechanical snubbers (safety-related and non-safety related) l installed in Farley Unit 2 were tested as described in the l response to Item 4a as a portion of the normal pre-operational testing conducted between December 1979 and March 1981.

REQUESTED ACTION

4. Submit a report of the results of the inspections, testing and evaluation requested in Item 1 to NRC within 45 days of the issuance date of this bulletin. Report the results of the inspections, testing and evaluation requested in Item 2 within 30 days after the inspection and testing have been completed. The response to Item 3 shall be submitted within 60 days of the issuance date of this bulletin. The results of the inspections performed for Item 3 shall be submitted within 60 days after the completion of the inspection.

The reports shall contain the following:

a. A description of the visual examinations and tests performed.

b. Number of snubbers examined and tested. Grouping by manu-facturer name, model number, and size is acceptable.

c. Number of failures identified; manufacturer name, model number, size, mode of failure, cause of failure, corrective action, snubber location, effect of failure on plant and system safety, and justification for continuing or resuming operation.

d. The above infomation shall also be provided for the snubbers exempted by Items 1c, 2c, and 3c.

RESPONSE TO Item 4a Testing of mechanical snubbers in Farley Nuclear Plant - Unit 2 included the following actions:

(1) Visual verification of installation noting general snubber condition, orientation, end connections. -

and numbering.

(2) Disconnection of one end of the snubber and the performing of a manual test over the range of stroke in both tension and compression.

a. Each snubber satisfactorily completing the test was reconnected and tagged.

. '. Enclosura II Page 3

b. Each snubber failing th'e test was removed and returned to the vendor for repair and/or replace-ment. The snubber was then appropriately replaced with a spare shown to be functionally operable. ,

i RESPONSE TO Item 4b I A total of 215 safety-related mechanical snubbers were inspected. '

All snubbers were manufactured by Pacific Scientific. The number l of snubbers tested, grouped by model number, is as follows. 3 i

PSA-1/4 PSA-1/2 PSA-1 PSA-3 PSA-10 TOTAL  !

129 39 -26 20 1 21 5 RESPONSE TO Item 4c As shown in the table below, seventeen (17) snubbers failed the functional test. The mode of failure on each of these seventeen snubbers was the same. Either the snubber was locked up, allowing no movement in the range of either tension or compression, or the l movement was restricted, allowing only limited inadequate stroke.

HANGER MARK NO. MODEL NO./ SIZE LOCATION SS-10319 PSA-1/4 CTMT Bldg.

SS-11991 PSA-1/4 CTMT Bldg.

SS-12155 PSA-1/2 CTMT B1dg. i SS-12254 PSA-1/4 CTMT Bldg. ,

SS-12346 PSA-1/4 CTMT Bldg. <

SS-12369 PSA-1/4 CTMT Bldg.

SS-12477 PSA-1/4 CTMT Bldg. l SS-12484 PSA-1/4 CTMT Bldg.

SS-12525 PSA-1/4 CTMT B1dg.

SS-12648 PSA-1/4 CTMT Bldg.

55-12723 PSA-1/4 CTMT Bldg.

SS-12848 PSA-1/2 CTMT Bldg.

SS-12889 PSA-1/2 CTMT Bldg.

SS-12900 PSA-1/2 CTMT Bldg. l SS-12940 PSA-1/4 CTMT Bldg.

CS00R198 PSA-1 CTMT Bldg.

RTDOR175 PSA-1/2 CTMT Bldg.

TOTALS PSA-1/4 11 PSA-1/2 5 PSA-1 1 PSA-3 0 PSA-10 0 Y

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l Enclosure II -

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Page 4 The cause of the snubber failures cannot be determined exactly in each case; however, it is felt that the failyres were caused either by mishandling during installation or during subsequent construction activities on neighboring equipment.

Failed snubbers were replaced with spare snubbers shown to be functionally operable. The failures had no effect on plant or system safety since this was a pre-operational test.

RESPONSE TO Item 4d All mechanical snubbers (safety-related and non-safety related) installed in Farley Unit 2 were tested as described in the response to Item 4a as a portion of the nonnal pre-operational testing conducted between December 1979 and March 1981.

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"8%q#o, UNITED STATES H,.O. i. ! ._ ~~

8  % NUCLEAR REGULATORY COMMISSION J' O* S*

u I REGION 11 b # 101 MARIETTA ST N.W., SUITE 310o. e- -

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ATI.ANTA, GEoAGIA 30303 U.C i!.

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RII:JPO O.c.:t ,

50-348 50-364 Alabama Power Company ATTN: R. P. Mcdonald Vice President-Nuclear Generation P. O. Box 2641 B4 mineh=, AL 35291 Gentlemen:

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The enclosed IF. Bulletin No. 81-01 is forwarded for your action with regard to your nuclear power facility. .

To assist the NRC in evaluating the value/ impact of each bulletin on all licensees, it would be helpful if you would provide an estimate of the manpower expended in the review. and preparation of the report (s)' required

- by the bulletin. Please estimate separately the manpower associated with corrective actions required by this bulletin.

4.

Should you have any questions regarding this bulletin or the actions required by you, please contact this cffice.

Sincerely, I

- . - A3 ,

C TNE__ _ _ .

James P. O'Reilly Director

Enclosures:

1.

2.

IE Bulletin No. 81-01 List of Recently Issued g

IE Bulletins cc w/ encl: \ ~

i W. O. Whitt, Executive Vice President ,. ;

F. L. Clayton, Jr., Senior Vice President fe? .~.0 2s3' 6 H. O. Thrash, Manager-Nuclear Generation ,[ ' *-

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0. D. Kingsley, Jr., Manager, Nuclear Engineering and Technical Services gg >'

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J. W. McGowan, Manager-Operations Quality Assurance ,. _

W. G. Hairston, III, Plant Manager .

W. C. Petty, Manager-Quality Assurance (Design and Construction) ~

R.. E. Hollands, Jr. , QA Supervisor