ML18157A166

Forwards Responses to Listed Questions Re Piping Insps & Replacements,Including Number of Points Inspected & Pipe Sections Replaced,Per 870115 Conversation

ML18157A166
Person / Time
Site:	Surry, North Anna, 05000000
Issue date:	01/27/1987
From:	Hardwick R VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:	Rubenstein L Office of Nuclear Reactor Regulation
References
NUDOCS 8702020729
Download: ML18157A166 (5)

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. I V11101NlA ELEC:TltIC A.NI> POWER COMPANY RicHMOND, V1ac:aun11. S026l January 27, 1987 Mr. Lester S. lubenstein PWR Project Directorate No. 2 D1v1s1on of PWR. Licensing-A U, S, Nuclear leiulatory Cmmniss1on Wa1hington, D, C, 20555

Dear Mr,

Rubenstein:

Per our conver1at1on on January 15, 1987, attached are the responses to your questions regarding the piping inspections and replacement at each of our nuclear power atations, Queations A, Bow many points did we inspect?

B, Where were the in1pect1one?

• D. Row many pipe 1ection1 did ve replace?

If you have any further qua1tioft1, plea1e contact u1, Very truly yours, t<J~~~~

R, J. Hardwick, Jr,

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!.Vm hit 1 A. Over 550 components have been in1pect,d, Each ae,ment of pipe between fittinas, and *ach elbow. wye, tee, and reducer i i con1idered a component, A typical p1pe tee has over 500 in1pection points a~ound the circumference and along the length of the joint. !lbowa have nearly 100 inspection points each. Straight piping run, are inspected at 3, 6, 9, and 12 o'clock at 1,veral locations along thair lengths, Subaequently, over 100,000 inapections have been made on Surry Unit 1 1):lping I

!, Inspectione included the majority of the condenaate and feedwater piping component* from the 4th point feedwater h,at*rs tc the main faedwater resulating valves. the feedwater recirculation linee, 1 of the 3 main feed~ater lines to the containment penttration, and another main ftedwater line to the 1team generator. Aleo inapected were *elected CO?llponents of thet Ccndeneate pipina between the 6th point and 4th point feedwater heaters.

Extraction 1team and main *team ~iping.

Steam generator blowdown piping to the pre111ure conti-ol valves and 1 B" train 1ndde containment and outside containment to the coolets, Auxiliary feedwater pipin&, the_ 3A pump discharge piping to the header and the pump r*circulaticn lin* to the orifice area, Charging pump (atainl*** 1teel) p1pina, the ditcharae header to the flow control valve.

Possible additional in1pection1 may be made on 1elected component& of the chargina letdown pipin1 to the orifice off the re1tn1rative heat exchanger and additional components in the ,team 1eu1rator blowdown piping.

C, Pipe wall thickne1s on Unit 1 ~1pins va1 datarmiued by the ultraaon1c

~ethod of non-de1truct1v1 te1tin1, D, Approximately St o! the total piping componente in1pect1d were below our acceptance criteria for minimum wall, In tome caaea, the component* which required ~*placement due to p1,e wall thinnin1 were 1eparated by 1hort run, of pipe or by pip1n~

component, that would require replacement uext refua11ns, So, 1n thoae ca*** the aeparating component, would alto be replaced for con1truction convenience.

Of the 550 component, 1n1pected 1 approximately 50 component, (leas than 10%) are being replaced.

e e Surn: U111 t 2, A. S1m1lar *to the 1n1pection1 performed on Surry Unit l, over 550 co~ponents are scheduled to be inspected on Unit 2. Thus far, approximately 200 of those co~ponents have been in1pected. Not counting the points examined on the ruptured pipe, over 3.5.,000 inspections have been made on Unit 2 piping.

B. The eccpe of piping to be inspected is the aame as that liated for Surry Unit 1.

C. Pipe wall thickness wa1 determined by the ultrasonic method of non-d11truct1ve testing.

• D. Of the 200 components thus far inspected, approximately 33 components are being replaced.

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e Borth Anna Unit 1 A. Approximately 4.900 inspection points werti examined, and all locations were above the minimum pipe wall thickness required.

Additional piping 1n1peetians *will be performed during upcoming outages.

B, These inapeet1ons were performed .on the main feedwater pump 1uct1cn piping and he&der and on the high pre1sure heater drain pUtUp discharge piping, C. The piping was inepected by using the ultrasonic method of non-destructive testing.

D. the piping wae determined .!!.21 to need replacement.

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e e Worth '1\na Uuit 2 A. Because Unit 2 has operated fewer hours than Unit 1 and because of the favorable results of the Unit l inspections. it waa determined no inspections were required on Unit 2 until the next refueling outage, B, N/A C. N/A D. N/A