ML18113A439

LER 1976-09-00 for St. Lucie Unit 1, Mechanical Pipe Restraints Supplementary Report No. 1

ML18113A439
Person / Time
Site:	Saint Lucie
Issue date:	06/10/1976
From:	Schmidt A Florida Power & Light Co
To:	Moseley N NRC/IE, NRC/RGN-II
References
PRN-LI-76-143 LER 1976-09-00
Download: ML18113A439 (14)

Text

NIIC FOflM 195 U.S.NUCLGAA flGOULATOIIV COMMIS ION DOCKET NUMOEf1 I 2-701~t NBC DISTBIOUTION Fol I ART 50 DOCKET MATERIAL 50-336 FILE NUMOL'll INCIDI',NT REPORT N.C.Mgs'eley FRoM:Flordia Power.8'ight Co.Miami, Flordia A.D.Schmidt DATE OF DOCUMENT 6-10-76 DATE RECEIVED 6-17-.76 QLCTTEA QOAIGINAL EICOPV ONOTOAIZGD

@UNCLASSIFIED PROP INPUT FOAM NUMOGA OF COPIES AGCEIVFD DESCRIPTION Ltr..trans the.following......,.'0 ENCLOSURE Licensee Event Report (R.O.76-9)on.,3-31-76

~Concerning Mechanical Pipe Restraints Supplementary Report 81.......(30 Carbon Signed Cys.Received)(4 Page's)PLANT NAME: St.Lucie 8 1 ACKNOWLEDGED,.D>>OT aZMOVz NOTE: IF PERSONNEL EfiPOSURE XS'INVOLVED., SEND DIRECTLY TO KREGER/J.COLLINS SAFETY BRANCH C11IEF: N 3 CYS FOR ACTXON LIC;ASST': K'ee FOR ACTION/INFORMATION ENVIRO M/-CYS Acss16 css.KiBIBHRII ssz ic is.FXL NRC PDR I&E 2 (3 SCHROEDER/XPPOLITO 04 NOVAK C111'CK R MES INTERNAL DISTRIBUTION tier hHMHi TEDI'.SCO/I IACCA Y E.N I'AER SIIAO VOT.Lt I I'.R./II UNC I I KREQQQJ~OLQ~NS LPDR: Ft.Pierce F.TXC NSIC EXTEIINAL DISTRIBUTION CONTROL NUMBER 6135.'

0 I~" Mtl h'l hh, heal'~~\~4~their hh-)'hhl hW)g'hi"~+Pg, hhh*"h~e~~~~~~"~Itl'~>h I~"3h"'<>f'" O h a I<<g hg hhhh hf Ih hh I h h'll Re 8'ulg)0 P.O, BOX 013100,>MIAMI, FLORIDA"3101 I//cg//g~Co~R Rg0I 77 1$5gpN I0RL t".:.','a.'~>>'>~I l.>///yygx-H FLORIDA POVsER B LiGHT GOl:><<t!Y June 10, 1976 PRN-LI-76-143 Mr.Norman C;Moseley, Director, Region II Office of Inspection and Enforcement U.S.Nuclear Regulatory Commission 230 Peachtree Street, N.N., Suite 818.Atlanta, Georgia ,30303

Dear Mr.Moseley:

.00CKOEO VS'>P 5oel'>>>>>gob~C4>I>, REPORTABLE OCCURRENCE 335-76-9 ST.LUCIE UNIT 1 DATE OF OCCURRENCE:

MARCH 31'976 MECHANICAL PIPE RESTRAINTS SUPPLEMENTARY REPORT NO.1 The attached Licensee Event Report is being submitted to supplement our initial report of April 12, 1976.Very truly yours, Vice President Power Resources MAS/cpc At tachment cc: Jack R.Newman, Esquire-Director, Office of.Inspection and Enforcement (40)Director,.-

Office of Management Information and Program Control (3) r I h Ui IJ CONTROL BLOCK: 1.UCENSEE'/'AME~01 FLSLZ1 0 0 7 89 14 15 REPOAT, REPORT CATEOORY TYPE SOURCE[001j coN'r~T~L 0 7 8 57 58 59 60 61 EVENT OESCRIPTION Qg P o rational testin LICENSEE EVENT REPORT Sf PRINT ALL Rf QUIRE 0 INFORMATION) 6 UCENSE EVENT UCENSE NUMBER TYPE TYPE 00000-00 41 1 11L000~1I 25 26 30 31 32 OOCKET NUMBER~EVENT OATC AEPORT OATE 5 0-0 3 3 5 0 3 3 1 7 6 0 6 1 0 7 6 68 69 74 75 80 of i in restraints snubbers was bein er-7 8 9 80 Qg'ormed durin the heatu for Post Core Hot Functional testin.At the 7 89[GD4]260'F heatu lateau five INC mechanical snubbers were found to be 80 7 8 9 80 Qo 5 locked u.The immediate action was to replace the defective snubbers 7 8 9 80 toad with o erable snubbers.All of the INC snubbers have since been replace 60 7 8 9 SYSTEM CAUSE COOE COOE[oa~j~zz~z 7 8 9 10 11 12 CAUSE OESCFIIPTION Qg As reviousl PRME COMPOI4ENT SUPPUER COMPONENT MANUFACTURER COMPONENT COOE A N G E R~A'B 2 1 0 43 44 47'N 17 re orted it was determined that oxidation of internal 7 8 9 80 to09 corn onents was the cause of the occurrence.

Subse uent factory labora-7 8 9 80 tor testin and anal sis showed the followin OTHER STATUS N A P>QQ~LE CONSEQUENCES 7 8 9 LOSS OR OAMAGE TO FACILITY TYPE OESCAIPTION EE L~l 7 89 10 PUBLICITY 7 8 9 7 89 FACVPf STATUS 9fi POWER Q~g 0 Loaoo J 7 8 9 10 12 13 FORM OF ACTIVITY COATENT RELEASEO OF RELEASE'AMOUNT OF ACTIVITY t11g~Z Z N/A 7 8 9 10 11 PERSONNEL EXPOSURES 7 8 9 11 12 13 PERSONNEL INJURIES 0ESCRIPTION

~4 0'0 7 8 9 11 12 METHOO OF 06COVERY 44 45 46 44 45 LOCATION OF RELEASE N/A N A N A N A N/A OISCOVEAY OESCRIPTION Preo erational Test Procedure 80 80 80 80 80 80 80 80 AOOITIONAL FACTORS'18 See Pa es 2 and 3 for continuation of Event&Cause Descriptions.

7 89 80 7 89 NAMEI M.A.Schop man PHONE 305/552-3779 80 GPO IIAI~6/7 REPORTABLE OCCURRENCE 335-7 6-9 SUPPLEMENTARY LER NO.l PAGE TWO Event Descri tion (Continued)

C by Pacific Scientific snubbers.Cause.Descri tion (Continued)

S/N 000377 The front.and rear caps of the snubber were removed.A thin layer of oxidation was found on the inside of both caps, and there was water inside the rear cap.The ball screw was opera-tional, and clearances between'internal components were normal.However, there was a large amount of rust sludge and water inside the center section which, caused rotational binding.The rotational binding resulted in resistance to thermal move-~ment.Also, the thrust bearing was installed incorrectly at.the factory, but this did not cause the snubber malfunction.

S/N 000343 This snubber was found to have an improper end fitting (i.e., no ball bushing), and its indicator bar was slightly bent.With the correct-end fitting, the snubber was opeiational, therefore, it was not disassembled.

S/N 000525 The front and rear caps were removed and the snubber interior was found to be clean..The ball screw was operational, and the clearances between internal components were normal.However,'here was slight, rotational binding in the center section.When the adaptor assembly was rotated one revolution, the.snubber began to operate,.but with a higher.than normal resistance to movement.The adaptor assembly was removed and a small amount of oxidation was found on the thrust bearing.The amount of oxidation was considered large enough to have caused the snubber malfunction.

S/N 000695 Same description as for 000525.

'i~'REPORTABLE OCCURRENCE 335-76-9 SUPPLEMENTARY LER NO..1 PAGE THREE Cause'escri tion (Continued)

S/N 000632": The'ront and rear caps were'removed.and'he snubber-interior:was found to be clean.'The ball screw.was operational, and the clearances between internal components were normal;However,;there-was rotational binding in the center section.The adaptor assembly was removed and a large amoun't of oxidation was found on~the thrust bearing..The oxidation caused the snubber malfunction.

FLORIDA POWER 8, LIGHT COMPANY June 10, 1976 PRN-LI-76-143 Mr.Norman C.Moseley, Director, Region II Office of Inspection and Enforcement U.S.Nuclear Regulatory Commission 230 Peachtree Street, N.W., Suite 818 Atlanta, Georgia 30303

Dear Mr.Moseley:

REPORTABLE OCCURRENCE 335-76-9 ST.LUCXE UNIT 1 DATE OF OCCURRENCE:

MARCH 31, 1976 MECHANICAL PIPE RESTRAXNTS SUPPLEMENTARY REPORT NO.1 The attached Licensee Event.Report is being submitted to supplement our initial report of April 12, 1976.Very truly yours, Vice President Power Resources MAS/cpc Attachment cc: Jack R.Newman, Esquire Director, Office of Inspection and Enforcement (40)Director, Office of Management Xnformation and Program Control (3)HELPING BUILD FLORIDA 0 r 4 1~~.~~P I I hl~~~f' CONTROL BLOCK: LICENSEE EVENT REPORT[PLEASE PRINT ALL REQUIRED INFORMATION) 6 UCENSEE'NAME~01FLSLS100 7 89 14 15 UCENSE NUMBEA 0 0 0 0 0-0 0 25 UCENSE TYPE.EVENT TYPE 41 1 11~01 26 3Q 31 32 REPORT REPORT CATEGORY TYPE SOURCE~01 cON'T~~T L 0 7 8 57 58 59 60 61 EVENT OESCRIPTION Q5 Prep erational testin~~OOCKET NUMBER 5 0-0 3 3 5 EVENT OATS 033176 REPORT OATE 0 6 1 0 7 6 68 69 74 75 80 1 of i in restraints snubbers was bein er-7 8 9 80 I.foimed durin the heatu for Post Core Hot Functional testin.At the 7 89~04 260'F heatu lateau, five INC mechanical snubbers were found to be 80 7 8 9 80.Qo g.locked u.The immediate action was to replace the defective snubbers 7 8.9 80 Qo 6 with operable snubbers.All of the.INC snubbers have since been replace 7 8 9 SYSTEM CAUSE COBE COOE[oa']~ZZ~S 7 8 9 10 11 12 CAUSE OESCRIPTION As reviousl COMPONENT COOE WPAE COMPONENT SUPPUER COMPONENT MANUFACTUAER ANGERA 17 43 B 2 1 0 N 47 48 re orted it was determined that oxidation of internal 80 7 8 9 80 Qg corn onents was the cause of the occurrence.

Subse uent.factory labora-7 89 FAC~STATUS%POWER Em L~l.7 8 9'10 12 13 FORM OF ACTIVITY CONTENT RELEASEO OF RELEASE AMOUNT OF ACTIVITY t11I~Z.Z N/A 7 8 9 10 11 PERSONNEL EXPOSURES 7 89 11 12 13 PERSONNEL INJURIES NUMBER, OESCRIPTION

'~4~00 0 7 8'9 11 12 OTHER STATUS N A PROBABLE CONSEQUENCES METHOO OF OISCOVEAY OISCOVEAY OESCAIPTION C Preo erational Test, Procedure 44 45 46 LOCATION OF RELEASE N/A 44 45 P N A N A 7 8 9 Qg tor testin and anal sis showed the followin 80 80 80 80 , 80 80 7 89 LOSS OR OAMAGE TO FACILITY TYPE OESCRIPTION Z 7.'8 9'10 PU8LICITY 7 8 9 N A N A N/A 80 80"80 AOOITIONAL FACTORS[]is]See Pa es 2 and 3 for continuation of Event&Cause Descriptions.

7 8 9 80 7 89 M.A.Schop man'HONE, 3 05/552 377 9 80 eFO eeS-eeT v,~

REPORTABLE OCCURRENCE 335-76-9 SUPPLEMENTARY LER NO.l PAGE TWO Event Descri tion (Continued) by Pacific Scientific snubbers.Cause Descri tion (Continued)

S/N 000377 The front and rear caps of the snubber were removed.A thin layer of oxidation was found on the inside of both caps, and there was water inside the rear cap.The ball screw was opera-tional, and clearances between internal components were normal.However, there was a large amount of rust.sludge and water inside the center section which caused rotational binding.The rotational binding resulted in resistance to thermal move-ment.Also, the thrust bearing was installed incorrectly at the factory, but this did not cause the snubber malfunction.

S/N 000343 This snubber was found to have an improper end fitting (i.e., no ball bushing), and its indicator bar was slightly bent.With the correct end fitting, the snubber was operational, therefore, it was not disassembled.

S/N 000525 The front and rear caps were removed and the snubber interior was found to be clean.The ball screw was operational, and the clearances between internal components were normal.However, there was slight rotational binding in the center section.When the adaptor assembly was rotated one revolution, the snubber began to operate, but with a higher than normal resistance to movement.The adaptor assembly was removed and a small amount of oxidation was found on the thrust bearing.The amount of oxidation was considered large enough to have caused the snubber malfunction.

S/N 000695 Same description as for 000525.

REPORTABLE OCCURRENCE 335-76-9 SUPPLEMENTARY LER NO.1 PAGE THREE Cause Descri tion (Continued)

S/N 000632 The front and rear caps were removed and the snubber interior was found to be clean.The ball screw was operational, and the clearances between internal components were normal.However, there was rotational binding in the center section.The adaptor assembly was removed and a large amount, of oxidation was found on the thrust bearing.The oxidation caused the snubber malfunction.

At I