ML19257A281

Final Rept Re Pressure Testing of Fuel Pool Cooling & Cleanup Sys Piping for All Units Above Aci 318-71 Limits. Portions of Two 2-inch Pipes Tested Above Limits.Caused by Designer Failure to Specify Alternate Testing

ML19257A281
Person / Time
Site:	Hartsville
Issue date:	12/06/1979
From:	TENNESSEE VALLEY AUTHORITY
To:
Shared Package
ML19257A278	List: ML19257A277 ML19257A281
References
NCR-HNP-A-072, NCR-HNP-A-72, NUDOCS 8001030542
Download: ML19257A281 (2)

Text

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ENCLOSURE HARTSVILLE NUCLEAR PLANT, ALL UNITS FUEL POOL COOLING AND CLEANUP LINES PRESSURE TESTED ABOVE ACI 318-71 LIMITS 10CFR50.55(e) REPORT NO.1 (FINAL) '

NCR ENP-A-072 On November 9, 1979, TVA notified NRC-0IE Region II, Inspector R. W. Wright,

, of a potentially reportable condition regarding pressure testing of fuel pool cooling and cleanup (FPCC) system piping for all units to pressures above ACI 318-71 limits. Ihis is'the final report on the subject reportable deficiency.

Descriction of Deficienev Portions of two 2-inch pipes, FPCg-220 and FPCC-264, in all four units were pressure tested to 384 lb/in g in accordance with ASME Section III, ND-6000, after they were embedded in concrete. Since these lines were not sleeved, it.sulated or otherwise protected frem the concrete, the pressure test violated ACI 318-71, paragraph 6.3.2.3, which states, "The maximum pressure to which any piping or fitting shall be subjected shall be 200 psi above atmospheric pressure."

The auxiliary building portion of these pipes was installed and tested and then embedded in concrete. The fuel building portien of these pipes was subsequently installed and tested, which repressurized the sections of the pipes already embedded in the auxiliary building to e level above 2

200 lb/in g.

Cause of Deficienev The deficiency occurred due to the designer failing to either specify alternate pressurization schemes which would permit pressure testing of these lines within ACI 318-71 limits or to provide separation of the pipes from the concrete.

Safety Imolications C. F. Braun has calculated the expansion of the pipe in the concrete to be less than 0.00009 inch. These lines are embedded in six feet of reinforced concrete yhich could not have been damagad significantly by imposition of 384 lb/in on the inside of an equivalent two-inch diameter concrete cylinder.

Therefore, no demage to the concrete structure occurred which would jeopardize the safe operation of the plant.

Corrective Action For the two pipes, FPCC-220 and FPCC-264, involved in the deficiency, no corrective action is necessary since the concrete was not damaged.

1667 287 a001088 '*

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Action to Prevent Recurrence GE informed TVA by letger of all piping which has required test pressures in excess of 200 lb/in and instructed TVA not to pressure test any of the piping which has been embedded but not wrapped or separated from the concrete until further direction is given. TVA has previously embedded portiens of four of the pipes listed by GE (FPCC-26, FPW-ll, FPW-29, and FPW 45 where FPW stands for fire protection water).

GE/C.F.Braunisreducingthesystemdesignpressureforthe{PCC-26 pipe so that the test pressure required will be less than 200 lb/in The embedded portions of the three FPW pipes were hydrostatically tested before embedment as required by specifications. Testing of the connecting lines through a nearby check valve where a blind flange can be placed will be performed pneumatically rather than hydrostatically. This alternate scheme will prevent theemgeddedportionofthepipefrembeingrepressurized above the 200 lb/in ACI 318-71 limit.

The requirement to wrap and thereby separate from the concre;e pipelines to be embedded which have test pressures in excess of 200 lb/in' above atmospheric

• pressure has been incorporated into applienble C. F. Braun specifications (400-03, 400-07, and 400-15).

Implementation of this requirement will prevent recurrence of this problem for future installations for embedded piping.

I667 288

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