ML19323D207
| ML19323D207 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 04/21/1980 |
| From: | Engelken R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V) |
| To: | Papay L SOUTHERN CALIFORNIA EDISON CO. |
| References | |
| NUDOCS 8005210262 | |
| Download: ML19323D207 (1) | |
Text
T/C so nora s
o UNITED STATES
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NUCLEAR REGULATORY COMMISSION n
i REGION V
- 8, 1990 N. CAllFORNI A BOULEVARD o
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SulTE 202, WALNUT CREEK PLAZA e,,,*
WALNUT CREE K, CALIFORNIA 94S96 April 21, 1980 Docket flos. 50-206, 50-361, 50-362 h
Southern California Edison Company P. O. Box 800 2244 Walnut Grove Avenue Rosemead, California 91770 Attention:
Dr. L. T. Papay, Vice President Advanced Engineering Gentlemen:
This Information flotice is provided as an early notification of a possibly significant matter.
It is expected that recipients will review the information for possible applicability to their facilities, fio specific action or response is requested at this time.
If further flRC evaluations so indicate, an IE Circular or Bulletin will be issued to recommend or request specific licensee actions.
If you have questions regarding this matter, please contact the Director of the appropriate IIRC Regional Office.
Sincerely,
.NT7me_CC-R. H. Engelken Director
Enclosures:
1.
IE Information flotice flo. 89-15 2.
List of Recently Issued IE Information flotices cc w/ enclosures:
J. M. Curran, SCE R. Dietch SCE
~ Seesano Qg
o SSINS No.: 6870 Accession No.
UNITED STATES 8002280660 NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT U
WASHINGTON, D.C.
20555 k
April 21,1980 IE Information Notice No. 80-15 AXIAL (LONGITUDINAL) ORIENTED CRACKING IN PIPING On fiarch 8,1980, the Commonwealth Edison Company reported to the NRC that slight leakage was observed from the "A" loop core spray injection piping during a reactor coolant system leakage test at their Guad-Cities Unit 2 Nuclear Power Station. The source of leakage was subsequently identified to be located adjacent to a shop weld joining a 90 elbow and a wedge section of elbow material used to extend the elbow to 105. Subsequent ultrasonic inspections revealed additional cracking in several other elbows in "A" and "B" core spray loops.
The cracks are located adjacent to welds and oriented transverse to the weld in the axial (longitudinal) piping direction.
The affected elbows have been removed and currently failure analyses are in progress.
Preliminary results from liquid penetrant examinations of the elbow interior surface in the counter bore / weld root area revealed axial oriented cracks on both sides of the weld in the counter bores adjacent to the weld roots.
From the limited metallography perfomed to date, the cracking mode appears to be intergranular stress corrosion cracking. The cracking, however, only appears to be slightly branched. A detemination as to whether or not the cracking extends into and across the welds cannot be made at this time.
It is significant to point out that these service sensitive lines, as defined by NUREG 313, had been examined on an augmented basis per NUREG 313 requirements.
Two of the affected welds were inspected ultrasonically at the current outage prior to the leakage being observed at the pressure test with no indication of cracking reported.
Further ultrasonic examinations, using standard AS!!E Section XI methods, performed after discovery of the leak clearly revealed the cracking (approximately 100% over the reference level).
Licensees are requested to inform NDE inspection personnel of the above stated information and to emphasize the need for care when performing circumferential UT scans of the weld and adjacent areas in piping components.
Particular importance should be stressed when the examinations are performed on BWR service sensitive 304 stainless steel piping and on PWR 304 stainless steel piping in stagnant systems.
This Information Notice is provided as an early notification of a possibly significant matter that is still under review by the NRC staff.
It is expected that recipients will review the information for possible applicability to their facility.
No specific action or response is requested at this time.
If you have any questions regardinq this matter, please contact the Director of the appropriate NRC Regional Office, i
o IE Information flotice No. 80-15 Enclosure April 21, 1980 RECEtiTLY ISSUED IE INFORMATION fl0TICES Information Subject Date Issued To flotice flo.
Issued 80-14 Safety Suggestions From 4/2/80 All power reactor Employees facilities with an OL or CP 80-13 General Electric Type SBM 4/2/80 All light water reactor Control Swiches - Defective facilities holding power Cam Followers reactor OLs or cps 80-12 Instrument Failure Causes 3/31/80 All holders of power Opening of PORV and Block reactor OLs and cps Yalve 80-11 General Problems with ASCO 3/14/80 All holders of Reactor Valves in Nuclear Application OL, CP, fuel fabrica-Including Fire Protection tion and processing Systems facilities 80-10 Partial Loss of Non-Nuclear 3/7/80 All power reactor Instrument System Power facilities holding Supply During Operation OLs and cps 80-09 Possible Occupational 3/7/80 All holders of Health Hazard Associated power reactor OLs with Closed Cooling Systems and near term cps 80-08 The States Company Sliding 3/7/80 All power reactor Link Electrical Terminal facilities with an OL Block or a CP 80-07 Pump Shaft Fatigue Cracking 2/29/80 All Light Water Reactor Facilities holder power reactor OLs and cps 80-06 Notification of Significant 2/27/80 All holders of Reactor Events OLs and to near tern OL aoplicants 80-05 Chloride Contamination 2/8/80 All licensees of nuclear of Safety Related Piping power reactor facilities and applicants and holders of nuclear power reactor cps
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