ML20038A093

Updated RO 76-05 on 760327 Insp of Steam Drum Relief Valves Revealed Surface Cracking on Nozzles.Cause Attributed to Stress Corrosion in High Oxygen Steam Environ.Valves Repaired & Returned to Svc

ML20038A093
Person / Time
Site:	Big Rock Point File:Consumers Energy icon.png
Issue date:	07/19/1976
From:	CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.)
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
References
76-05, 76-5, NUDOCS 8110060062
Download: ML20038A093 (1)

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• 15 23 28 30 31 32 UE DOCKET NUMBER fvENT cATE GEPo#f Daff' O 1 CONT l l l l0j [IJ. [0 l5 l5 l-l01115 l 5 l l Ol 3l 2l 7l7161 l 0 l 7 l 11 o l 716 l' cataconv Sg Sj 56 59 60 61 68 69 74. 75 80 7

t N bESCAIPTON Q p_ :ia: nd -d::rme bspection of steam drum relief valves revealed surface crack-l 00 7 8a q

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lir on the nozzle of $1ve of :n ca valves a a ytant. During seir! welding of re-l o

80 7 89

-vaivas, dye penetrant indications were noted in all valve l

Q l placement nozzi e

80 7 89 o5 lbodies adjacent to the seal veld area. The valves were repaired me&wreseed to amece l

60 7 89 icna, requirezents and returned to service. (a0-5-76) l oe 80 7 89 pasa

'N CN CoM9aNENT coog unsu aCit a votafou E Icici [_Ej lV l A l1. l V l E l Xl (NJ lC l7 l1l0 l

[NJ 7 89 to 11 12 17 43 44 47 48 CAUSE DESCAIPTON l Nozzle cracking ifr-etnr'19-9UC~ material is postulated to have been caused by stress l

oe 60 7 89 09 l corrosion in the high oxygen steam a=_m_ine environment. Body cracking is costulated l

EO 7 89 3 lto be propagation of minor easting defects _dwrine-thermal stress conditions of adiaeend "oN0:0v'

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'sNs' oscovtRY oESCR9fCN s powen ofwen status DE l0 l 0 l 0 l l N/A l W l Inservice Inspection-Dye Penetrant Tds 9_

10 12 13 44 45 45 60 7 8

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12 80 7 8 9

10 11 44 45 PEASCNNEL EXPCSUAES

%wSER 7788 CESCA8fCN 12 l0 l 0 ! 0] yl N/A l

60 7 89 11 12 13 PEASONNEL INJUQTS l

tot uGE R CESCAPTCN l0l0l0l l N/A 14 60 7 89 PRO::ABLp 12

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Q l Postulated complete cracking uay have caused primary system leakage 60 7 89 LOSS OA DAMAGE TO FACluTY f*81 De 5CE9f CN l

QW] N/A 80 7 89 10 PUBLCTY gg l N/A l

80 7 89 ACOITONAL FACTORS H Causa Description-Centd) nozzle seal welding. Inspection frequency increased to j

( ie 60 7 89 l two-units per operating cycle.

l i9 60 7 89 pDRACOCK110060062 760719 05000155 g

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