ML19270G993

Responds to V Stello 790525 Ltr Re Possible Design Problem W/Feedwater Piping.Forwards Isometric Drawings of Feedwater Lines in Containment & All Pipe Supports & Results of Stress Analyses for Feedwater Lines

ML19270G993
Person / Time
Site:	Calvert Cliffs
Issue date:	06/19/1979
From:	Lundvall A BALTIMORE GAS & ELECTRIC CO.
To:	Reid R Office of Nuclear Reactor Regulation
References
NUDOCS 7906220315
Download: ML19270G993 (6)

Text

s BALTIM ORE GAS AN D E LECTRIC CO M PANY GAS AND ELECTRIC DUILDING BALTIMOR E, M ARYLAN D 21203 June 19, 1979 ARTHUR E. LU NOVALL,JR.

vics Pass.or e sv a Office of Nuclear Reactor Regulation U. S. Nuclear Regulatory Commission Washington, D. C. 20555 Atta: Mr. Robert W. Reid, Chief Operating Reactors Branch #h Division of Operating Reactors

Subject:

Calvert Cliffs Nuclear Power Plant Unit Nos. 1 & 2, Docket Nos. 50-317 & 30-318 Feedvater System Desien Information

Reference:

NRC letter dated 5/25/79 from Stello to PWR Licensees, same subject.

Gentlemen:

The enclosed infor:aation is being submitted in response to the referenced letter, which described a possible design problem with feedvater piping. This information covers only items 1 through h of the request.

The remainder vill be fe w ded in our 60-day response.

1) Enclosed are two isometric drawings of the feedvater lines in the containment, one drawing per unit. All feedvater piping in the containment is 16" diameter schedule 80. Also enclosed are forty-nine drawings detailing all pipe supports on these lines.

Enclosure 1 cross-references the pipe support drawings with the notations used on the stress isometric drawing to show the location of the pipe supports.

All check valves are 900 # valves made of cast carbon steel ASTM A-216, Gr. WCB, buttvelded with a pressure seal cap or bolted body joint. The valves have tilting disk, a velded or integral seat ring and are stellited.

2. The basic results of the stress analyses for these feedvater lines are enclosed as Enclosure 2. Each pipe is designated on the calculation sheets. The computer printouts resulting from these stress calculations are over six hundred pages in length and are not included in this submittal. They can be made available upon request. What is included are the pipe supports, no::le, and penetration loadings as well as a flexibility analysis for each line. An explanation of the data presented is included as Enclosure 3.

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, ,F2brication History

1. The feedvater piping is made of carbon steel ASDf A-106 Gr. C.

Feedvater nozzle bodies are made of SA 508 Class II material with the safe ends made of SA 508 Class I materf al. Reducers are AS7M A-23h Gr. WPC. Elbows are made from ASDI A-23h Gr.

WPB. The feedvater ring is also ASTM A-106 Gr. C.

2. There is no piping velded to the feedvad;er ring. Elbows are shielded metal arc (SMA) velded using a preheat temperature of 60 - 350 F and no post-veld heat treatment. All piping velds are either manual gas tungsten arc (GTA) velds or SMA velde.

Preheat temperature was under 200 F. Post-veld heat treatment consisted of stress relieving to 1150 P. The joint confis:uration is open butt with a single bevel and no backing ring.

If you have any questions concerning this infor=ation, please contact us, Very trulv yours, d ss l

r, ec: J. A. Biddison, Esquire G. F. Trowbridge, Esquire Mr. E. L. Conner, Jr. - NRC Mr. J. W. Brothers - Bechtel 2348 ()95

Enclosure No. 1 Unit No. 1 Stress Iconetric Drawing No. 91-093B (SK-M-600)

Pipe Support Number

( As denoted on stress isometric ) Pine Sunnort Drawine Number (s)

Pipe Line # 16"DB1-1018 H-1 12600-2690, 2691 R-1 12600-2692 R-2 12600-2693, 269h, 2695 R-3 12600-2696, 2697, 2698 Pipe Line # 16"DB1-1019 H-2 12600-2700 H-3 12600-2701 R-1 12600-2702, 2703 H-h 12600-2704 R-2 12600-2705, 2706 H-5 12600-2707, 2708 R-4 12600-2709 H-6 12600-2710 H-7 '12600-2711 R-5 12600-2712 R-3 12600-2713, 271h H-7 12600-2715 Unit No. 2 Stress Isometric - Drawing No. 91-h07-B (SK-M-998)

Pipe Line # 16"DB1-2018 H-1 13600-3186, 2187 R-1 13600-2188, 2189 R-2 13600-2190 R-3 13600-2191, 2192 2348 096

Pipe Line # 16"DB1-2019 H-3 13600-2193 Hh 13600-2194, 2195 R-10 13600-.2196, 2197 H-5 13600-3198 R-h, R-5 13600-2199, 2200 H-6 13600-2201, 2202 R-8 13600-2203 H-7 13600-220h H-8 13600-2205 R-9 13600-2206 R-7, R-6 13600-2207, 2208 H-2 13600-2209 2348 097 t

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ENCLOCURE NO. 3 Restraint Loadincs For each restraint, (labeled as R-X on the stress isometric drawing) the thermal, operating basis earthquake (OBE), design basis earth-quake (DBE) and seismic restraint lo,ds are presented. Seisnic restraint loads are loads resulting frcm the differental pipe movements which would occur during the earthquake. The total restraint design load is the absolute swenstion of the thermal, DBE and seismic restraint loads rounded off to the next highest thousand pounds. The thermal and seimsic pipe movements in the three directions are also presented.

Hanner Loadings For each hanger (labeled as H-X on the stress isometric drawing) the thermal load, the weight of the pipe, insulation and operating fluid are listed in addition to the seisnic anchor movement and the DBE loads.

For spring hangers which are not subject to thermal leading, the loading used to design the hanger spring component is equal to the sum of the weights of the pipe. insulation and operating fluid or that figure rounded off the the next highest 500 pounds. The load used to design the support steel (also referred to as " dead weight" load) is equal to the cwn of the weights of the pipe, insulation and operating fluid multiplied by a factor of 1.07 and rounded off to the next highest 500 pounds.

For rigid supports the sw=mation of the loads depends on the direction of the thermal and dead weight loads. If the two act in the'same direction (i.e. both loads act in the negative direction), thr> absolute value of these loads are added to the seicmic loads, and the total is rounded off upwards to the next 1,000 pounds. If the therral and dead weight loeds do not act in the same direction, the higher of these two loads is using absolute summation to the loads due to seicnic anchor move-ment and DBE loads.

If two sets of thermal loads are listed, the upper value refers to the normal operating condition, and the lower value applies to the accident condition thermal load value. The higher of these values is used to calculate the total load for support steel and rigid hanger ccmponent design.

Penetration Loading For the feedwater penetration, the thermal expansion loads, dead weight loads, OBE loads, DBE loads and seismic nnchor movement loads are listed along with the movements associated with all these forces. The two sets of therral loads and movements refer to the nornal operating ecndition (upper value) and the accident condition (lower value).

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Nezzle Loadings For the steam generator nozzles. the thermal and dead weight loads and coments are listed alcng with the OBE, DBE, and seismic anchor loads and moments. For the analysis on Unit No. 1 two values are listed for the OBE and DBE leads. These represent loadings in the X-Y and Y-Z planes which are stated separately because of the limited capability of the ecmputer code used at the time. The Unit No. 2 analysis lists the total seismic loads resulting fran an updated code that ec=bised all seicnic leads into a single value. The total net design load is the absolute surmation of the thermal, dead weight, OBE, and seismic anchor movenet' loads.

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