ML20073G388
| ML20073G388 | |
| Person / Time | |
|---|---|
| Site: | Limerick  |
| Issue date: | 09/27/1994 |
| From: | Hunger G PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| NUDOCS 9410040145 | |
| Download: ML20073G388 (4) | |
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A 10CFR50.55a(g)(5)(HI)
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Nuclear Group Headquarters v
965 Chesterbrook Boulevard l
i Wayne, PA 19087-5691 September 27,1994 Docket No. 50-353 License No. NPF-85 r
i U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555 Subject-Limerick Generating Station, Unit 2 Request Relief for First Ten Year interval inservice Inspection Program Regarding System Hydrostatic Pressure Testing Gentlemen Attached for review and approval is Relief Request No. RR-17 for the Limerick Generating Station (LGS), Unit 2, First Ten Year Interval inservice Inspection (ISI) Program. Relief Request No.
RR-17 requests relief from the requirements of Subsection IWA-4400 of Section XI of the American Society of Mechanical Engineers (ASME) Bouer and Pressure Vessel (B&PV) Code, 1986 Edition, which requires that a system hydrostatic test be pedormed as stipulated in Subsection IWA-5000, following repairs by welding, or the installation of replacement items by welding, on Class 1,2, and 3 components.
PECO Energy Company is requesting relief from the ASME Code required pressure test, as Indicated above, in order to facultate implementation of a Unit 2 plant system modification designed to eliminate portions of the piping network (i.e., cut and cap) associated with the Main Steam isolation Valve Lankage Control System. This modification work is planned for the next refueling outage at LGS Unit 2 which is currently scheduled to begin at the end of January, t
1995. Performing the elevated hydrostatic pressure test following the piping modification as required by the ASME Code, would impose a burden since the level of safety yielded by pedorming the test at normal system pressure (1005 psig) is commensurate with pe1aiiviirig the test at an elevated pressure (1085 psig). In lieu of performing the required ASME Code hydrostatic test following implementation of this modification, we propose to follow the criteria delineated in ASME Code Case N-416-1, 'Altemative Pressure Test Requirement for Walded Repairs or installation of Replacement items by Welding Class 1,2, and 3 Section XI. DMsion 1,"
to satisfy the requirements for the post-repair pressure testing of this modification.
The detals and justification for relief are explained further in the attached Relief Request. We '
would appreciate your cooperation in providing an expeditious review of Relief Request No.
RR 17, and request that the NRC grant relief from pedorming the ASME Code required hydrostatic post-repair pressure test by January 15,1995.
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9410040145 940927
- f a PDR ADOCK 05000353 l
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September 27,1994 Page 2 If you have any questions or require additional information, please do not hesitate to contact us.
Very truly yours, b.0./bar k,
G. A. Hunger, Jr.
,V Director - Licensing Attachment cc:
T. T. Martin, Administrator, USNRC, Region I (w/ attachment)
N. S. Perry, USNRC Senior Resident inspector, LGS (w/ attachment) i I
i
Umerick Generating Station, Unit 2 First Ten-Year Interval inservice Inspection Program RELIEF REQUEST NO. RR-17 i
Docket No. 50-353 Page 1 of 1 Limerick Generating Station, Unit 2 RELIEF REQUEST NO. RR-17 Revision 0 1.
IDENTIFICATION OF COMPONENTS 1
2' Oass 1, Main Steam isolation Valve Leakage Control System piping (Unes DBA-211), associated with Modification P00017.
II.
CODE REQUIREMENTS FROM WHICH RELIEF IS REQUESTED ASME Code,Section XI,1986 Edition, IWA-4400 requires a system hydrostatic test to be performed in accordance with IWA-5000, after repairs by welding, or the installation of replacement items by welding, on Class 1, 2, and 3 components. Relief is requested from this post-repatr/ replacement hydrostatic test requirement.
lit.
BASIS FOR RELIEF i
I Modification P00017 requires the cutting and capping of each of four existing 2' Main Steam isolation Valve Leakage Control System pipes, near their connection to the Main Steam piping l
(between containment isolation valves). The weld joining the cap to the remaining pipe stub requires j
a Section XI hydrostatic test. Because of the configuration of piping in this area, this weld cannot i
be appropriately isolated from the remainder of the Cass 1, Main Steam Piping System. (e.g. using the Main Steam isolation valves as the test boundary valves could result in damage to the inboard valve, due to pressurization under the valve disc). This would then require pressurization of the entire Class 1 boundary to the required hydrostatic test pressure of IWB-5222 (1.08 times the nominal operating pressure corresponding with 100% rated reactor power, when tested at 200*F).
The burden imposed by the described situation is not commensurate with the increased level of safety yielded by the higher pressures associated with the hydrostatic test as compared to the pressures associated with the normal system leakage test (e.g.1085 psig vs.1005 psig). Therefore, this specific request is made for permission to use ASME Section XI Code Case N-416-1, to satisfy the requirements for the post-repair pressure testing of this modification.
IV.
ALTERNATE PROVISIONS The subject weld will be pressure tested during the conduct of the routine Class 1 Leakage Test, which will be conducted at the end of the refueling outage. The test pressure associated with this test is the nominal operating pressure associated with 100% rated reactor power. The test temperature used will be the normal Class 1 Leakage Test temperature. Additionally, the construction Code NDE performed on the subject welds will be in accordance with the methods and acceptance criteria of the 1992 Edition of ASME Section 111.
Use of the Code Case will be documented on the NIS-2 Form associated with this repair actMty.
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