ML20062E524
| ML20062E524 | |
| Person / Time | |
|---|---|
| Site: | Calvert Cliffs  |
| Issue date: | 12/05/1978 |
| From: | Lundvall A BALTIMORE GAS & ELECTRIC CO. |
| To: | Reid R Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 7812080096 | |
| Download: ML20062E524 (2) | |
Text
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4 DALTIMORE GAS AND ELECTRIC COMPANY gas AND CLECTRIC BUILDING j
BALTI M O R E. MARYLAN D 21203 ART **um E. LUN0VALL,Ja.
vms P se.asar
- Sweet, Office of Nuclear Reactor Regulation U. S. Nuclear Regulatory Commission Washington, D. C.
20555 h
Attn:
Mr. Robert W. Reid, Chief i
3 Operating Reactors Branch #h Division'of Operating Reactors
Subject:
Calvert Cliffs Nuclear Power Pla.
- UnitirN6s'.~ TTY,~Toeket Nos. 50-317 A 50-318 Inservice Inspection (ISI) Prostram /
d Gentlemen:
The ASME Boiler and Pressure Vessel Code,Section XI currently I
requires that Class 1 and 2 niping be examined to fulfill the requirement for an Inservice Inspection of Nuclear Comnonents. All piping, Class 1 and 2, is to be examined using the examination methods listed in Table IWB-2600 (Class 1) and IWC-2600 (Class 2).
Where volumetric examination is required, ultrasonic inspection is utilized due to restrictions innosed by using radiography.
Pining examination by ultrasonic testing is to be done per the provisions 'of Article 5 of Section V of the ASME code, since Appendix I of Section XI applies only to Class 1 and 2. ferritie vessels, 21/2 inches and over in vall thickness.
Article 5 of Section V requires that all indications with a response greater than 20 percent of the reference level shall be investigated to the extent that the operator can evaluate the ::hape, identity, and loca-tion of all such reflectors.
The above requirement becomes burdensome due to the number of irrelevant indications which could occur in this region due to noise.
Additional difficulties arise because extra examination teams with examiners who are qualified Level II (or better) must be utilized. The use of these highly qualified examiners to record and evaluate indications which are not associated with true defects results in two undesireable conditions:
- 1) The examiners are not available time-vise to conduct meaningful inspections;
- 2) The examiners are unnecessarily exoosed to radiation which increases their total man-ren burden and reduces their ultimate availability for future examinations in high radiation areas.
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In light of the above, we propose the following alternative criteria to Article 5 of Section V of the Code:
All evaluations which exceed 100 percent of reference level vill be evaluated, and all indications which exceed 50 percent of reference level vill be recorded for future reference, as necessary.
For vessels with>21/2 inches of wall thickness, the evaluation requirements of Appen-
. dix I,Section XI of the ASME Code vill continue to apply.
We have discussed these new criteria with Mr. Glenn Walton of the Office of Inspection and Enforcement, Region I, and he has informed us that his office vill consider the criteria to be in effect as of the mailing date of this letter. For record purposes, it is our intention to formally implement the revised criteria as of January 1,1979, and ve,.therefore, ask your concurrence prior to that date.
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Very truly you/ '
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cc - J. A. Biddison, Esquire G. F. Trowbridge, Esquire Mr. E. L.' Conner, Jr. (NRC)
Mr. Glenn Walton, NRC (King of Prussia) e G
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