ML19350B268
| ML19350B268 | |
| Person / Time | |
|---|---|
| Site: | Calvert Cliffs  |
| Issue date: | 02/27/1981 |
| From: | Grier B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| To: | Lundvall A BALTIMORE GAS & ELECTRIC CO. |
| References | |
| NUDOCS 8103200193 | |
| Download: ML19350B268 (1) | |
Text
m-UNITED STATES
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NUCLEAR REGULATORY COMMISSION g.*;
e REGION I e,
- 8 631 PARK AVENUE
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KING OP PRUSSIA, PENNSYLVANIA 19406 n
Docket Nos. 50-317 N'
FEB 2 71981 g g(( j (/33 50-318 h 'C
.6, g %,, %S p,, l a g Baltimore Gas and Electric Company ATTN:
Mr. A. E. Lundvall,, Jr.
13 Vice President, Supply w%
P. O. Box 1475 g,
Baltimore, Maryland 21203 N
1&TTf Gentlemen:
The enclosed IE Information Notice No. 81-04, " Cracking in Main Steam Lines" is forwarded to you information.
No written response is recuired.
If you desire additional information regarding this matter, please contact this office.
Sincerely, ESnt/<+-N s bl VV e H. Grier 1 rector
Enclosures:
1.
IE Information Notice No. 81-04, with 2 attachments CCNTACT:
L. E. Tripo (215-337-5232) cc w/encis:
R. M. Douglas, Manager, Quality Assurance L. B. Russell, Plant Superintendent T. Sydnor, General Supervisor, Operations QA R. C. L. Olson, Principal Engineer J. A. Tiernan, Manager, Nuclear Power R. E. Denton, General Supervisor, Training and Technical Services b108200\\
SSINS No.
6535 Accession No.:
8011040265 IN 81-04 UNITED STATES NUCLEAR REG'JLATCRY CCV.MISSICN OFFICE OF INSPECTICN AND ENFORCEMENT WASHINGTCN, D.C. 20555 February 27,1931 IE Information Notice No. 81-0?:
CRACKING IN.v.AIN STEAM LINES Description of Circumstances:
The Virginia Electric Power Company prcmptly notified the NRC on February 23, 1931 that a radiography examination, during the ongoing steam generator replacement cutage at Surry Unit 1, had revealed a lengthy crack indication in the I.D. counterbore area of a weldment en the in-line "T" fitting whith connects the vertical n.n of 30-inch piping to the safety relief valve header and 30-inch =ain steam line of Steam Generator "A".
This piping connection is located outside the containment penetration i=ediately u; stream of the main steam isolation valve as shown in the attached sketch.
A visual and dye penetrant examination on the pipe I.D. surface of the welc ent nearest the containment penetration established that the cracking extended about 120 9 around the fitting counterbore between the ? o' clock to 8 o'cicck position.
Cracking was also observed in the weld counterbore at the cpposite end of the T-fitting during visual examir.ation of the piping interior.
Radic-graphic examination of "B" and "C" main steam line T-fitting welds disclosed crack indications at similar locations.
Metallurgical specimens of the cracking were trepanned from the T-fitting of the "A" eain steam line for analysis. Centrolled excavation and depth measurements of the crack at its mid-length indicated a crack depth of about 0.090" in this location.
The cause of cracking has not yet been established.
VEPCO has planned an ultrasonic examination.of similar weld.ents in Surry Unit 2 main steam lines utili;:ing " Hot Piping" ultrasonic techniques.
Preparations are also being made to ultrasonic examine similar weldments at North Anna Unit 1, currently in cold shutdown for refueling.
Recc=endation to Licensees:
This information is provided as an early notification of a significant safety matter that is still under review by the NRC staff.
It is expected that recipients will review the information for possible applicability to their '-
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plants.
For those plants having are currently in a refueling or i
that a ultrasonic and/cr radiogr DUPLICATE DOCUMENT counterbore areas of the T-fitti operations, unless some current Entire dccument previously is available.
entered into system under:
E0 //d//024,5 Am No. of pages:
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