ML20214S888

Safety Evaluation Rept Granting Relief from Hydrostatic Testing After Repair to ASME Code Section Xi,Class 1,reactor Coolant Pump Seal Injection Line

ML20214S888
Person / Time
Site:	Summer
Issue date:	06/03/1987
From:	NRC
To:
Shared Package
ML20214S886	List: ML20214S883 ML20214S888
References
NUDOCS 8706100032
Download: ML20214S888 (4)

Text

f SAFETY EVALUATION REPORT VIRGIL C. SUMMER NUCLEAR STATION DOCKET NUMBER 50-395 RELIEF RE00EST - ASME CODE SECTION XI REOUIREMENTS I. INTRODUCTION license was issued on TheVirgilC.SummerNuclearStationoperatina)requiresthatthroughout August 6, 1982. Paragraph 10 CFR 50.55a(g)(4 the service life of a boiling or pressurized water-cooled nuclear power facility, components (including supports), which are classified as ASME Code Class 1, Class 2, and Class 3, shall meet the requirements set forth in the applicable Section XI Editions and Addenda of the ASME Boiler and Pressure Vessel Code to the extent practical within the limitations of design, geometry and materials of construction of the components.

the South Carolina Electric & Gas By a letter(the Company dated May)29, licensee 1987, relief from hydrostatic testing requested after repair to the ASME Code Class 1 reactor coolant pump seal injection line. In lieu of the required hydrostatic test, nondestructive examinations consisting of surface and visual examination of the welds and an inservice leak test at nominal pressure were proposed.

II. EVALUATION OF RELIEF REOUEST The licensee has requested written relief f rom an examination require-ment that he has determined to be impractical in accordance with paragraph 10 CFR 50.55a(g)(5)(iii). We have evaluated the information in the referenced letters and have determined that the examination requirement, from which relief is requested, is impractical, as discussed in the following paragraphs.

RELIEF REQUESTED The licensee intends to perform penetrant test (PT) examinations on the repairs made to the reactor coolant pump seal injection piping and to perform an inservice leak test VT-2 examination at nominal operating pressure and temperature. These tests are being proposed in lieu of performing the hydrostatic testing, as required by ASME Code /Section

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XI,1977 Edition, through and including the Sumer 1978 Addenda. The hydrostatic testing is proposed at the end of the 10 year interval.

1 CODE REQUIREMENT i

Subsequent to repairs or modifications by welding, which penetrate ,

the pressure boundary on piping greater than one inch diameter, conduct a hydrostatic test on piping where such repairs or modifi-cations were performed.

Pursuant to ASME Code,Section XI, 1977 Edition, through and including Sumer 1978 Addenda, hydrostatic test pressure is 1.10P or 2574 psig at 100*F where P isthenormaloperatingpressureofsSalinjection at100%ratedreEctorpower.

BASES FOR REQUESTING RELIEF The licensee has requested relief from the hydrostatic test on the reactor coolant pump seal injection piping because:

1. the repair work complies with Section XI; l

2. catastrophic failure of repair would not represent an unanalyzed condition, i.e., small break LOCA; and

3. since there are no isolation valves on this line, a hydrostatic >

test of this weld would require raising the entire connected reactor coolant system to hydrostatic test pressure. Such a test would expend a pressure test cycle for the reactor coolant system which may adversely affect fatigue capability of the system.

In addition, the licensee stated that performance of the required hydrostatic test on the reactor coolant pump seal injection piping subsequent to the weld repair would not be desirable for the following reasons-l

1. potential for damage to the reactor coolant pump seal I assemblies;

2. isolation and preparation of the reactor coolant pump seal injection system woubi result in additional radiation exposure to personnel;

3. requirement for removal and replacement of the reactor coolant system pressurizer safety valves;

4. requirement for defueling and refueling the core creates the possibility of damaging the fuel;

5. needless exposure of the reactor coolant system and the reactor coolant pump seal injection system to thermal and hydraulic cyclic stresses could cause otn.r problems to occur; and

6. potential damage to system int < mentation.

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. PROPOSED ALTERNATIVE EXAMINATIONS & TESTS Prior to entering Mode 2, the following examinations will be performed on the affected reactor coolant pump seal injection piping welds, except Item 5, which will be completed at the end of the next inservice inspection interval:

1. examination on the root pass weld surface pursuant to ASME Code Section V, Article 5;

2. PT examination on each groove weld pass and final groove weld pass surface pursuant to ASME Code Section V, Article 5;

3. PT examination on the final reinforcement pass weld surface pursuant to ASME Code Section V, Article 5;

4. performance of inservice leak test VT-2 examination at nominal operating pressure and temperature; and

5. performance of hydrostatic test at the end of the 10 year interval.

The alternate examination, items 1 through 3, will be perfonned in accordance with approved written procedures by qualified personnel during and upon completion of the Reactor Coolant Pump Seal injection pipe weld repair. The performance of an inservice leak test will be performed during heat up prior to entering Mode 2.

III. CONCLUSIONS We have determined that relief from the Code required hydrostatic test on the reactor coolant pump seal injection piping is justified because: a fuel hydrostatic test would unnecessarily expend a pressure test cycle for the reactor coolant system; performance of the inservice leak test is conducted at fuel operating pressure while the hydrostatic test is conducted at only a slightly higher pressure, 110% of operating pressure; catastrophic failure of the repair would not represent an unanalyzed condition; and the repair work complies with Section XI. The effort required to comply with the hydrostatic test does not provide a comensurate gain in safety of the plant. We, therefore, conclude that relief from the hydrostatic test requirements of Section XI of the ASME Boiler and Pressure Vessel Code, 1977 Edition, i through Sumer 1978 Addenda, may be granted pursuant to paragraph ,

10 CFR 50.55a(g)(6)(i) for the repair as requested.  !

We have concluded, based on the considerations discussed above, that: (1) certain specific requirements of Section XI of the ASME Boiler and Pressure Vessel Code,1977 Edition through Sumer 1978 Addenda are impractical and (2) such relief is authorized by law, will not endanger life or property or the comon defense and security and is otherwise in the public interest giving due consideration to the burden upon the licensee if such relief j were not granted. 1

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Principal Contributors: J. Hopkins, Project Directorate 11-1 J. Hayes, Project Directorate 11-1 W. Hazelton, Materials Engineering Branch C. Sellers, Materials Engineering Branch Dated: g, w ms my 1

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