PLA-5462, Comments on Draft Regulatory Guide DG-1112, ASME Code Cases Not Approved for Use
| ML021560434 | |
| Person / Time | |
|---|---|
| Site: | Susquehanna  |
| Issue date: | 05/20/2002 |
| From: | Shriver B Susquehanna |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| PLA-5462 | |
| Download: ML021560434 (2) | |
Text
Bryce L. Shriver PPL Susquehanna, LLC Senior Vice President and 769 Salem Boulevard Chief Nuclear Officer Berwick, PA 18603 t
Tel. 570.542.3120 Fax 570.542.1504 blshriver@pplweb.com v
pp k~TM 2 0 2`C)Qý U. S. Nuclear Regulatory Commission Attn: Document Control Desk Mail Station OP 1-17 Washington, DC 20555 SUSQUEHANNA STEAM ELECTRIC STATION COMMENTS ON DRAFT REGULATORY GUIDE DG-1112, "ASME CODE CASES NOT APPROVED FOR USE" Docket Nos. 50-387 PLA-5462 and 50-388 The following are PPL, Susquehanna LLC's comments on Draft Regulatory Guide DG-1112, "ASME Code Case Not Approved."
Comment # 1 Code Cases N-561 and N-561-1 Alternative Requirements for Wall Thickness Restoration of Class 2 and High Energy Class 3 Carbon Steel Piping,Section XI, Division I.
Regulatory Guide
Description:
Neither the ASME Code nor the Code Case has criteria for determining the rate or extent of degradation of the repair or the surrounding base metal. Reinspection requirements are not provided to verify structural integrity since the root cause may not be mitigated.
Comment:
These reasons do not appear applicable to published Code Cases N-561 and N-561-1, which contain the following specific requirements:
3.1 (d) - The predicted maximum degradation of the overlaid piping and the overlay over the design life of the restoration shall be considered in the design. The predicted degradation of the piping shall be based on in-situ inspection and established data for similar base metals. If the weld overlay is predicted to become exposed to the corroding medium, the predicted degradation of the overlay shall be based upon established data for base metals or weld metals with similar chemical composition to that of the filler metal used for the weld overlay.
6.0 (d) - Follow-up inspection shall be scheduled as necessary to confirm any design assumptions relative to rate or extent of future degradation.
Document Control Desk PLA-5462 Comment # 2 Code Cases N-562 and N-562-1 Alternative Requirements for Wall Thickness Restoration of Class 3 Moderate Energy Carbon Steel Piping,Section XI, Division I.
Regulatory Guide
Description:
Neither the ASME Code nor the Code Case has criteria for determining the rate or extent of degradation of the repair or the surrounding basemetal. Reinspection requirements are not provided to verify structural integrity since the root cause may not be mitigated.
Comment:
These reasons do not appear applicable to published Code Cases N-562 and N-562-1, which contain the following specific requirements:
3.1 (d) - The predicted maximum degradation of the overlaid piping and the overlay over the design life of the restoration shall be considered in the design. The predicted degradation of the piping shall be based on in-situ inspection and established data for similar base metals. If the weld overlay is predicted to become exposed to the corroding medium, the predicted degradation of the overlay shall be based upon established data for base metals or weld metals with similar chemical composition to that of the filler metal used for the weld overlay.
6.0 (d) - Follow-up inspection shall be scheduled as necessary to confirm any design assumptions relative to rate or extent of future degradation.
Sincerely, B. L. Shriver copy: NRC Region I Mr. S. L. Hansell, NRC Sr. Resident Inspector Mr. T. G. Colburn, NRC Sr. Project Manager