ML18078A489
| ML18078A489 | |
| Person / Time | |
|---|---|
| Site: | Salem  |
| Issue date: | 11/27/1978 |
| From: | Librizzi F Public Service Enterprise Group |
| To: | Schwencer A Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 7812110150 | |
| Download: ML18078A489 (2) | |
Text
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OPS~G Public Service Electric and Gas Company 80 Park Place Newark, N.J. 07101 Phone 201 /430-7000 November 27, 1978 Mr. Albert Schwencer, Chief*
Operating Reactors Branch #1 Division of Operating Reactors*
U.S. Nuclear Regulatory Commission*.
Washington, D.C.
20555
Dear Mr. SChwencer:
INTERPRETATION OF TECHNICAL SPECIFICATIONS AUGMENTED INSERVICE INSPECTION PROGRAM FOR STEAM GENERATOR CHANNEL HEADS SALEM GENERATING STATION NO. 1 UNIT DOCKET NO. 50-272 In May, 1976, liquid penetrant inspection of the steam generator channel heads on No. 1 Unit revealed the presence of cladding flaws.
Flaw indication was very minimal in Nos. 11, 12, and 13 Steam Generators.
The detected flaws were most heavily concen-trated in a 2-foot by 4-foot area in the upper half of the cold leg side of No. 14 Steam Generator.
To resolve the detected flaws, reference was made to Code Case 1738, in which the ASME Boiler and Pressure Vessel Code accepts surface indications in cladding, pro-vided such indications are confined to the cladding itself.
To determine whether the flaws penetrated the base metal and to provide baseline data for future inspections, an ultrasonic examination was initiated on No. 14 Steam Generator.
The in-spection area was confined to a 12-inch by 18-inch area, roughly in the center of the 2-foot by 4-foot area of No. 14 Steam Gen-erator, exhibiting the heaviest concentration of cladding flaws and being the highest stressed area of the channel head.
Location holes were drilled to permanently delineate this area and to pro-vide attachment of the specially designed ultrasonic equipment.
On June 9, 1976, the cladding depth of No. 14 Steam Generator was successfully determined ultrasonically.
On June 10, 1976, a base-line ultrasonic examination was performed on the* previously de-scribed area.
The data, when interpreted, indicated that the cladding flaws previously determined by dye penetrant inspection were detectable by ultrasonic examination from the O.D. of the I
channel head.
Also, it was determined the depth of a major flaw 7 812 110 150 95-2001 (200M) 2-78
Mr. Schwencer 2 -
11-27-78 in this group was indicated to be no greater than 1/8-inch below the cladding surface, and, therefore, within the boundary of the stainless steel cladding.
The ultrasonic inspection of No. 14 Steam Generator now serves as the baseline preservice surveillance examination for the cladding flaws.
Inspection commitments for the next three refueling out-ages consist of monitoring the same area, as defined by the exist-ing locator holes, using the.same ultrasonic procedures.
To supplement the ultrasonic inspection of flaw progression in the specified area of No *. 14 Steam Generator, a visual examina-.
tion technique using a TV camera will be utilized to monitor for surf ace propagation of the flaws on the inner surf ace expanded to include the 2-foot by 4-foot flaw area previously revealed by the initial dye penetrant examination.
The TV examination will be taped for future inspection comparisons.
The inspection of the No. 14 Steam Generator (cold leg side) over the next three refueling outages will provide.a basis* for any con-tinuation or expansion of the augmented ISI Program.
Limiting the inspection to the No. 14 Steam Generator in no way compromises the safety of the other steam.generators.
Documented baseline data and future inspection data will provide*' timely and accurate information as to flaw progression.
In summary, Technical Specification Surveillance Requirement 4.4.10.1.2 is interpreted as limiting the television inspection.
to the No. 14 Steam Generator (cold leg),channel head, since this is the only area where the visual indications could be correlated with an ultrasonic examination.
Very truly yours,
)
- vz;
~-y"'"'
F. P. Libri~zi General Manager -
Electric Production