ML20055D486

Requests Authorization to Use Encl ASME Boiler & Pressure Vessel Code Case N-395 Re Laser Welding for Sleeving Process Described by Oct 1990,per 10CFR50.55a,footnote 6

ML20055D486
Person / Time
Site:	Farley
Issue date:	07/02/1990
From:	Hairston W ALABAMA POWER CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
NUDOCS 9007090008
Download: ML20055D486 (3)

Text

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' Alabama Power Company 40 inverness C:nt:t Parkway.

Post Office Box 1295 Birmingham. Alabama 35201

, Telephone 205 868-5581 W. G. Hairston, lil Senior Vice President uiear operanons Alabama Power July 2, 1990- msmern ercsnrern 10CFR50.55a i

-Docket Nos. 50-348 =i 50-364 l U.S. Nuclear Regulatory Commission .li ATTN: Document Control Desk '

Washington, D.C. 20555 Gentlement Joseph M. Farley Nuclear. Plant

• ASME Code Case N-395, Laser Velding 1 Alabama Power Company is currently developing contingency plans for. steam .

'i generator maintenance for Farley Unit 2. . The Unit--2 refueling outage is.

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scheduled to start in mid-October:1990. Dependent on the steam generator

! tube eddy current testing results, tube sleeving may be required. As presented at a meeting with the NRC Staff oniJune 7, 1990,.Vestinghouse is developing a laser velded steam generator tube sleeve for'use in the Fall' j of 1990.

ASME Boiler and Pressure Vessel Code Case N-395, Laser Velding (attached), ,

l has not been' authorized for use by;the.NRC-Staff in accordance with L

10CFR50.55a, footnote 6. In that this code case-provides guidance for use ,

l of the laser velding process, the NRC Staff ~is requested:to review Code  !'

Case N-395 and-authorize its-use at Parley Nuclear Plant'for the sleeving process described above by October'1990. y i

If you have any questions, please advise. -j Respectfully u nitted,  !

,i V. G. Ilairston, III ..

-l VGil,III/ REM:mgd 21.28 Attachment cci Mr. S. D. Ebneter Mr.'S. T. Hoffman f

.Mr. G. F. Maxwell- 810 I 9007090000 900702 i-P PDR -ADOCK 05000348 I PDC k,  ;

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, r CASE N-395 1 CASES OF ASME BOILER AND PRESSURE YESSEL CODE Approval Dess: February 30,1984  ;

See Numerica!Inden hw espiretten

• end any reetfirmation deten.

Case N 396 wire feed,'or prior weld metal buttering of one or both ,

Laser Welding joint faces.

Section lil, Division 1 (d) Postweld Rest Treatment  ;

i (a) the addition or deletion of postweld heat j

. treatment;

' Inquiry: .May laser welding be ned under Section (6) a change in the postweld heat treatment ',

III, Division '1, to join P Nos. 8,10G,41,42,43, and 44 temperature and time nonge, materials not exceeding */4 in,in thicknem?

(5) Ces (a) a change from a single shielding gm to any ,

i Reply: It is the opinion of the Committee that leer' other single shielding' gas or to a mixture of shielding welding may be used under Section Ill, Division 1, to gases, or a change in specified percentage composition of '

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. join P.Nos. 8,10G, 41,42,43, and 44 materials not shielding gas mixture; 4 4

exceeding */4 in. In thickness, provided that: (6) the addition or deletion of one or more of L (a) a Welding Procedure Specification shall be p:e. the following: shielding gas, trailing shielding gas, back.

i pared and qualified in accordance with the require. ing gas, or plasma removing gas; _

ments of Section IX; the following essential variables (c) a change of more than 5% in the flow rate shall apply: of one or more of the following: shielding gas, trailer.-

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- (1) Joints shielding gas, backing gas, and plasma-removing gas; (a) a change in the type of groove; (d) any change of environment shielding, such

, (6) the addition or deletion of a backing; as from vacuum to an inert gas or vice+ersa; -l

- (e) an increase in the qualified fit up gap. (e) a change in the position or_ orientation of r

(2) Base Metals _ plasma removing gas jet relative to the workpiece_(e.g.,

(a) a change in base metal P. Number, type,or coaxial transverse to beam).

grade. When joints are to be made between base metals (6) Dectrical Characteristics ,

from two different P-Numbers (and two different (a) any change in the beam pulsing frequency-i' groups), a procedure quali6 cation must be made for the and pulse duration from that quali6ed; _

s applicable combination of base metals even thaugh pro- (6) a change in one or more of the following:

cedure qualification tests have been made for each of the lens focal length, focal distance, and spot aise; - .

two bue metals welded to itself. (c) a change in mode of operation from pulsed I

. (6) Where the measurement of penetration can to continuous or vice versa;c i '

be made by visual or mechanical means, requalification (d) a change in the wattage of more than 12%

is required where the base metal thicknem differs by from that quali6ed; 20% from that of the test coupon thickness. Where the (e) a change in energy distribution'across the measurement of penetration cannot be made, requalifi- beam (i.e., multimode or gaussian);

cation is required where the base metal thickness differs (f) a change in energy received by the work ,

i by 10% from that of the test coupon. piece.

(3) FillerMetals _

(7) Technique

- (e) the deletion or addition of filler metals;, (a) the addition or ddetion of beam oscilla- >

, (6) for filler metal additions, any change from tion; the nominal specified anasysis of the filler metal quali- (6) a change in width, frequency, or dwell time

Sed; of beam oscillation;

, (c) any change in the method by which filler (c) a change from single to multiple pass or metal is added, such as preplaced shim, top strip, wire, vice versa;:

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CASE (continued). l 1

L ' N-395 CASES OF ASME BOILER AND PRESSURE VESSEL CODE ,

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(d) a change in the type or model of the laser (i) the addition of a wash pass, welding equipment; (6) Requalification is required for any changes of ,

j (e) a change in welding speed of more than the essential variables from those quali6ed.

12%, or lens to work distance of more than 15%, from (c) The performance qualification for laaer weld.

those qualified; .

ing operators shall duplicate the test coupons, test speci.

- (f) a change from the melt.in technique to , mens, and requirements of the Welding Procedure .

the keyhole technique of welding, or vicewems; Specification.

(g) a change from welding from one side to (d) This Case number shall be shown on the Data ,

welding from both sides or vice verse; Report Form.  !

(h) a change in the method ofinitial and inter-paw cleaning; i

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