ML20126C546

Interim Deficiency Rept:Re Subsurface Defects in Containment Corner Junction T-welds.Caused by Undesirable Weld Nugget or Bead Shape Deposited at Roof.Resultant Cavity Areas Will Rewelded

ML20126C546
Person / Time
Site:	River Bend
Issue date:	01/14/1980
From:	Kirkebo J STONE & WEBSTER ENGINEERING CORP.
To:
Shared Package
ML20126C544	List: ML20126C540 ML20126C546
References
NUDOCS 8004040057
Download: ML20126C546 (54)

Text

.

9 STONE 6 WEBSTER ENGINEERING CORPORATION s

r3 CHERRY HILL OPERATIONS CENTER (s/

3 EXECUTIVE CAMPUS. P.O. BOX 520o CHERRY HILL, NEW JERSEY 08o34 TWX 710 892-0147 710-892 0148 e on U*'o".x MU" "'" " '

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waSMsNGTON D C.

Mr. J.

E.

Booker January 14 1980 Manager - River Bend Project J.O. No. 1$210 Gulf States Utilities Company RBS-4612 P. O.

Box 2951 Response Not Required Beaumont, TX 77704

Dear Mr. Booker:

FILE No. C9.25.1.1 CODE OF FEDERAL REGULATIONS REPORTABLE DEFICIENCY - 10CFR50.55(e)

RIVER BEND STATION - UNIT 1

References:

1.

S&W Letter No. RBS-4466 dated November 19, 1979 2.

Graver report dated December 6,1979 (enclosed) 3.

S&W report dated January 1980 (enclosed)

As a follow-up to your report to the commission on the containment corner junction weld (T-joint) under 10CFR50. 55(e) requirements, we are providing our findings of the cause and corrective action to resolve the deficiencies.

As used in this letter and the enclosed reports, the term " weld defect" or

" de f ec t" is used as defined in the American Welding Society's document AWS. A3.0-76, Welding Terms and Definitions.

The investigations by Craver and S&W, identified in Reference 1, have been completed.

The following is a summary of those investigations:

Graver's Investination (See Enclosure I)

Graver's investigations centered on the cracking being caused by eq ui pme nt and/or procedure.

They proceeded to create conditions they felt were the cause of the cracking present during production welding.

These conditions were to modify the various parameters which could have caused the weld defects.

The evaluated paraneters were:

Nuclear Document Control JAN 161980 80040400 5-7

January 14, 1980 f

RBS-4612

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The effects of the various hook-up connections possible with the DART 2108 dual head submerged are welding equipment l

h b.

Varying the number of shielded metal arc weld root passes c.

Changing the submerged-arc welding electrode flux combination d.

Varying the current and/or voltage e.

Changing the preheat, interpass, and post-heat temperatures.

S&W Investigation (See Enclosure II) i S&W's investigations were based on a metallurgical approach to determine j

the cause and corrective action for the weld defects.

The metallurgical investigation var completed in accordance with the requirements of

(

E&DCR No. P-M-(G)-1046.

i In addition, S&W has investigated to determine if weld deficiencies I

exist in locations other than the root area.

This was accomplished l

by grinding into the Unit I assemblies at the River Bend jobsite.

The investigation showed that the indications of cracks were, in fact, either slag inclusions or erroneous interpretations of UT signals.

There were no cracks in the weld other than in the root area.

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Conclusion of S&W/ Graver Investigation i

S&U's report (Enclosure II) has determined that the cause of the cracking was undesirable weld nugget or bead shape deposited at the root.

If the cracks are removed, the remaining weld material is

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metallurgically acceptable.

The results were confirmed by Figures 9 and 10 of the report which show the open crack surface having a j

globular and not a fibrous structure which confirms a welding-related shrinkage solidification crack.

A more complete summary of F

the cause can be found under the " Discussion, Conclusion, and Recommendation" section of Enclosure II, pages 3 and 4.

f The actual welding technique that was used did not adversely affect j

the metallurgy to impair the toughness of the weld or the heat affected i

zone.

The impact tests indicate adequate toughness.

The tests were i

U performed at 0 F and 40 F.

However, the tests at 40 F are the ones relevant to our discussions, as they meet the ASME III Class MC code I

requirements for the lowest service temperature of approximately 70 F.

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i The specification reguirement for the base material to qualify for impact strength at 0 F is conservative compared to actual service conditions.

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Januan 14, 1980 RBS-4612 JEB 3.

o In their investigation, Graver has come to the same conclusion as S&W for the cause of the problem (see pages 17 and 18, Section 2.4 of j

Enclosure I).

To preclude the problem from recurring, the most l

effective method to accomplish proper bead shape / nugget would be to redefine the weld electrode position and the number of shielded

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metal are weld root passes.

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Safety Implications The containment is a safety-related structure and is described in I

Section 6. 2.1 of the RBS PS AR.

The function of the containment is i

to act as an essentially leaktight structure and limit the release of fission products in the event of a postulated design basis i

accident.

If the weld defects identified in this report were to have f

remained undetected, the integrity of the containment vessel could i

have been jeopardized in the event of a design basis accident.

l Therefore, we have concluded that the weld deficiencies, if they l

had remained uncorrected, could have adversely affected the safety of j

operation of the nuclear power plant.

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Corrective Action E

During the evaluation process for the cause, a more refined UT i

technique was used to evaluate the root zone area.

S&W recommends a sample retesting of two Unit I assemblies using a 60 dual i

transducer search.

If the results reflect a rejection of greater than 50 percent, S&W recommends removing the entire weld which includes the defective root zone from one side only.

For areas having less than 50 percent rejection, the unacceptable ultrasonic indications will be removed and replaced with sound metal.

All resultant cavity areas will be rewelded to restore the containment corner junction welds to the originally specified ASME III, Class MC code requirements.

Detailed work procedures will be developed by Graver and approved by S&W

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prior to rework.

The repair welding will be done onsite using manual and semi-automatic procedures.

i Should you need further clarification of the enclosed reports, please I

contact us.

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Very truly yours,

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CALJ

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i J. A. Kirkebo j

Project Engineer Enclosures DH:SLP End u e r

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EGME O29816 22

4627-2 G19 DEC I P}n% 23 Lwar srsinusx December 6, 1979 f

Project Engineer, J.O. Nos.12210 (Unit 1),12330 (Unit 2)

Attention:

Lead Mechanics Engineer Stone & Webster Engineering Corporation 3 Executive Campus, P.O. Box 5200 Cherry Hill, NJ 08034 i

SUBJECT:

Contract Number RBS-219.710-COS6 Containment Shell Reactor Containment Vessel River Bend Station - Units 1 and 2 Gulf States Utilities Comoany Gentlemen:

Attached is the sumary status report entitled, "Cause-and-Corrective Action Analysis Concerning Sub-Surface Defects Found in River Bend Corner Junction Tee Welds" dated December 4,1979.

This report is the result of findings as reflected in the title of the reocrt and is forwarded for your information.

Very truly yours, GRAVER ENERGY SYSTEMS, INC.

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R. 'M. tanboroug b Contracts Manager Attachment Project Engineer, J.0. Nos.12210 & 12330 (S&W - CH) cc:

Contracts Manager (S&W - Site)

C. G. White (S&W - CH)

Manager, Procurement Quality Control Div. (S&W - Bos) (3)

Gulf States Utilities Co. (4) i r

i Nuclear Document Centrol

.tM 1 61980

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Ob79lateoco(,

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i RIVER BEND PROGRAM, JOB ORDER NO. 61040N l

t CAUSE-AND-CORRECTIVE-ACTION ANALYSIS CONCERNING SUB-SURFACE DEFECTS FOUND i

IN RIVER BEND CORNER JUNCTION TEE WELDS I

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Summary Sta:us Reper:

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f Prepared by:

B. L. Baird Da:e:

December 4,1979 i

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FOREWORD i

This is a summary status report which recaps the results of prior work done on a cause-and-correc ive-ac-Jon analysis I

concerning sub-surface defects found in River Bend corner i

junc. ion tee welds, and presents new information obtained 3

from additional work performed on the investigation of this

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problem.

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CONTENTS SECTION TITLE PAGE FOREWORD 11 I

i CONTENTS 111

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1.0 INTRODUCTION

1 2.0 NEW WORK COMPLETED SNCE THE LAST JOINT SdcW/

GRAVER MEETING 7

i 2.1 WORK COMPLETED UNDER PART A 7

i 2.2 RESULTS OBTAINED FROM THE WORK COMPLETED UN-DER PART A 9

2.3 EdLFRETATION OF THE i

RESULTS OBTAINED FROM THE WORK COMPLETED UN-

. DER PART A 15 2.4 DISCUSSON OF THE RESULTS OBTAINED FROM THE WORK l

COMPLETED UNDER PART A 17 2.5 WORK COMPLETED UNDER PART B 20 s

3.0 REFERENCES

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1.0 INTRODUCTION

l Graver Nonconformance Report (NCR) No. 77 (Reference (1)) covers a non-conformity in River Bend corner junction tee welds which were made, in i

conferrnance with Graver Welding Procedure 302N (Reference (2)), using a dual-head submerged are automatic welding machine manufac:ured by ogden E.ngineering Corporation and marketed under the model name DART 2108.

These tee joints are a full-penetration, double-bevel groove weld After fit i

i up and tacking, one inliial pass is made by hand welding. Subsequen: passes are made using the DART 2108 submerged are automatic welding machine.

This dual-head machine deposits two passes, simultaneously, from both sides of the tee joint.

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The nonconformity covered by NCR No. 77 is identified as "unaccep:able linear dise::ntinuities". Two prior reports, and one reper: supplement, cover-f Ing investigative work done.on this nonconformity have been written. (See References G), (4) and 0).)

f The ' unacceptable linear discontinuity which is te subjec: of de above ear-j lier repercs, as-well-as this particular report, is a c ack produced in de root j

area, taking the-form illustrated in de sketch contained in Figure 1.

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The cause of de nonconformance identified in NCR No. 77 was unacceptable i

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penetration characteristics of the firs: submerged are pass due to; (a) major varia:icns in welding current, and (b) variations in elec: rode pcsition. The primary corree:ive action identified in NCR No. 77 was the medlilcation of de submerged are welding equipment used to make the corner junction tee l

welds in orde- :o permi; welding c.:rrent and electrode pcsition to be l

l controlled.

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After NCR No. 77 was written, Graver management made the de-Nion that no addi:lenal comer junction tee welds would be made using Welding Proce-dure 302N (Reference (2)) un-dl after major med! dica:icns to de DART 2!Ca j

automatic welding machine have been completed. in de interim since this decir.icn was made, de welding of comer junc:!cn tee joints ha.s been accom-plished as a hand operation, in conformance with Graver Velding Procedure i

305N (Reference (6)).

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SKETCH OF Cross-sEcTios o;; CORNER 7UNICTlCN TE E WELb I LLU STRATIN s-THE CHARACTER,lSTic CRACK WHl;CH is THE SUBJECT OF THE CAUS E-ANb -

Co RR.ECTlVE-ACT104 ANALYS I S D1SCU SSED t N T H 1.,s REpo@.7, j

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The cause and cortdve action statements contained in NCR No. 77 were based on the ' investigative work summarized in a Graver report dated 7/2/79.

(See Reference 0).)

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On September 18, 1979, the contents of Reference (3) were reviewed at a joint Stone 6: Webster / Graver meeting. As a result of questions raised at $is mee:ing, a decision was made to re-examine the cause-and-cor dve-ac:fon analysis summariced in Reference O).

Reference (4) is a repoh dated October 25, 1979, summarizing the results of this re-examination, and the j

c=nclusions drawn from it..

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Reference (4) argued that NCR No. 77 (Reference (1)) and the July 2nd repor; i

(Reference O)) were in error with regard to the identifica:!cn of " major l

variations in welding current" ar one of the two causes which produced the

ub-surface cracks that ara the citica.l de ect covered by the nonconform-

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i (The second identified cause descibed in References (1) and Q) was ance I

" variations in ejecrode pcsition". This was not chailanged in the new se: of

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c=nclusiens presented in Reference (4).)

i The Oc:ober 25th report (Reference (4)) concluded the following:

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(1)

The welding current and voltage requirements identified in Welding Procecure 302N (Reference (2) were maintained when the corner junc-tion tee weids were produced using the DART 2103 automatic welding l

machine; and lack cf control of these parameters did not produce the t

sub-surface c acks.

I (2)

The two primary causes cf the sub-surface cacks were:

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(a)

Use of low preheat, interpass, and pos: heat temperatures.

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(b)

Use cf a sub are elec: rode - flux combination which produces f

weid: wit more hardenability thr.n is required.

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Based on the above iden-Jfled causes, the recommended cor ec-ive aCIdens are*

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Wejds to be made in the future usine Weldine P-ocedure 302N:

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Raise the preheat, interpass and pes: hea temperaraes.

l 2.

Change the sub are ele = rode - ilux combination to one which produces welds with min! mum hardenability.

(b)

Existine corner lunction welds oreviousiv made usine Welding Procedure 302N:

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Re-examine the welds using an adequate UT testing tech-ruque.

i 2.

Remove all rejec:able defecer and repair by hand ivelding l

using a we! ding procedure dat includes adequate preheat,

. interpass, and pest heat requiremenu.

On Oc:eber 30,1979, a draf of a plan covering additional work to be done to verify er disprove the conclusions centained in the Oc:cber 23th report (Reference (4)) was prepared. (See Reference (7).) The plan called for de following:

(a)

Weld, UT inspec: and mac o-see: ion four corner junction tee join:

mock-ups. The first would be welded, exac.ly as the corner junction tee joins were welded, using Welding Procedure 302N and the DART 2108 automatic welding machine. The second would be welded identically to the first, except that a minimum prehea:/inte:;, ass / pes: hea:

temperar.:re of 300"F would.be employed. The third would be welded identically to the second, except tha: 6e welding wire would be changed from Linde 40 to L!nc=Inweld L-61 (a lower hardenabill:y c=mposition dan L!nde 40). The four6 would be welded identically to the mird, excepi dat the welding wire would be c".anged to Line:1nweld L-40 (a lower hardenability compositien : nan Line:Inweld L-61).

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(b)

Maka cc:ual or simulated repair welds in the abova four mock-ups using a procedure cailing for 330"F prehea: prior to are gouging, followed by manual repair welding using a minimum preheat /interpass/ post hea:

temperatre of 300 F.

On Oc:ober 31, 1979, the October 25th report (Reference (4)) and the plan covering additional work (Reference (7) were reviewed at a joint Stone &

Webster / Graver meeting. At this joint meeting, S & W expressed some skep.-

i ticism concerning the conclusions contained in the October 25th report con-I cerning the probable influence of both preheat /interpass/ post hea: tempera-ture, and welding rod hardenabill:y, on the initiation of the sui > surface cracks covered by NCR No. 77. S & W also expressed the beilef that the penetration characteristics (degree of penetration of the initial sub are passes into the hand welded area at the root of the joint) of the inliial submerged 4

are passes were cf greater influence dan either of the above.

In deference to the views expressed by S & W at the October 31st meeting, Grave agreed to revise the plan covering additional work as follows:.

(a), The second mock-up would be changed to one welded identi-My to the first (per Welding Procedure 302N, using the DART 2108 automatic welding machine), with the exception that the number of hand passes would be increased from one to four, and the welding current ic be used on the first four sub are passes (made two-at-a-time from both sides of the joint) would be reduced by approximately 20% The additional hand passes and the reduced current on the initial sub are passes would be introduced in order to ' reduce the degree of penetration of the ini:!al sub are passes into the hand welded area at the root of the joint.

(b)

The third mock-up would be deleted.

On November 5,1979, Supplement No. i to the Oc:ober 25th report was wri::en. (See Reference (5).) This supplement was divided into wo parts.

Par I contains a revised pian for additional work, incorporating suggestions which evolved from the joint S & W/ Graver meeting held on October 31st.

Par: 2 contains documentation supporting the conclusion contained in the i

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October 25th report (Reference (4)) $at the welding current rnd voltage requirements identitled in Welding Procedure 302N (Reference (2)) we maintained when the corner junction tee welds were produced using the l

DART 2108 automatic welding machine.

1 In the interim since November 5th, the work descihed in Par I of Reference j

(5) has been completed. This repor presents the results of this new work.

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200, NET WORK COMPLETE.D SINCE THE LAST 3OINT S&W/ GRAVER MEET 1NG f

The plan covering the new work completed since the last joint S 6: W/ Grave i

meeting (held on October 31,1979)is defined in Par: 1 of Reference (3). This I

pian covers a two-part program.

Par: A addresses the development of additional information pertinent to eliminating, or reducing the incidence of, the characteristic sui > surface crack illustrated in Figure 1; in cases involving l

new corner junction tee welds made with the sub are process.

Part B I

addresses the developmen of information which would be used as the basis for a repair procedure to be employed to repair existing corner junction tee joints welded, prior to May,1979, using Precedure 302N and the DART 2108 submerged are automatic welding machine.

t 2.1 Work Comeleted Under Par A 2.1.1 Mock-Ues Four corner juncilon tee weld mock-ups were made using the DART 2108 dual-head submerged are automatic welding j

- machine-The Lincolnweld SA-750 motor generator sets suo-l plying power to the machine were hooked up with the elec-l trede leads coupled to the taps providing a relatively steep voir ampere outpu: curve. This is the book-up used when au I

River Bend corner junc !cn tee welds were made with the DART 2108 machine. The mock-ups were welded as fouows:

I Mock-Uo No.1: Per Welding Procedure 302N Mock-Uo No. 2: Per Welding Procedure 302N with the fol-lowing changes:

(a)

Number of hand passes ine eased frem one to four.

(b)

Current on the initial two dual-head sub are passes reduced by 100 amps. Weld wire diameter reduced fr:m i

1/8 inch to 3/32 inch for these passes.

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Mock-Uo No. 3:

Per Weldng Procedure 302N with the fol-lowing changes:

t Minimum preheat /interpass/ post heat temperature raised to 300"F.

5 Mock-Uo No. 4: Per Welding Procedure 302N with the fol-lowing changes:

l (a)

Minimum preheat /interpass/ post heat temperature raised I

to 300 F.

(b)

Welding wire changed from Linde 40 to Lincolnweld L-60,a. lower hardenability composition.

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i 2.1 2. Instrumentation l

(a)

' Current and Voltage:

t The weldng current and voltage cutput of each of the i

two automatic welding systems feedng power to the DART 2108 automatic welding machine were continu-5 ously recorded.

i (b)

Temperature:

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In the case of Mock-Ups No. I and 2, the preheat and i

interpass temperatures were measured with temperature i

indicating crayons. In the case of Mock-Ups No. 3 and 4, the preheat /interpass/ post heat temperatures were 1

continuously measured by thermocouples and recorded en a chart.

These temperatures were aise checked with temperature indicating c ayens.

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2.1.3 Insoecden (a)

Magnetic Par-lcle:

After completing the root passes, and after completing

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the last sub are passes, the mock-up welds were magnetic particle inspected.

(b)

Ultrasenic Tesdng:

l After completing the last sub are passes, the mock-up f

welds were ultrasonic tested, l

2.1.4 Destruedve Tes-ing After inspection, the mock-ups were cut, and macro-sections i

were made at selected locations, i

t 22 Resuhs Obtained from the Werk Comoleted Under Part A l

i 2.2.1 Mock-Uo No.1 I

e (a)

Current and Voltage Charts:

The chart covering continuous recording of 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />,18 minutes,6 seconds of actual are time was studied. There was no evidence on the chart of abnormal welding current or voltage.

(b)

Magnetic Particle Inspection and Ultrasenic Testing:

No c seks were found.

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(c)

Mac o-Sectioning:

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Mccro-sectioning indcated that tha inidal sub are passe:

had not fully penetra:ed the hand welded root pass. The minimum width of hand welded root pass was in excess of 1/4 inch. (See sketch contained in Rgure 2.)

2.2.2 Mock-Uo No. 2 (a)

Curren: and Voltage Chans:

The chart covering continuous recordng of 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />,11 minutes and 55 seconds of actual are time revealed no evidence cf abnormal welding current or vol: age.

(b)

Magnetic Partide Inspec. ion and Ultrasonic Testing:

No c acks were found.

(c)

Macro-Sectioning:

Macre-secdoning revealed tha: the ini:ial sub are passes had ne: fully penetrated the hand welded root passes.

The minimum width of hand weld remaining in the roo:

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area was in excess of 1/2 inch. (See sketch contained in Rgure 3.)

2.2.3 Meck-Uo No. 3 (a)

Current and Voltage Charts:

1 The chart covering continuous recordng of 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />,10 minutes and 10 seconds of actual are time revealed' no evidence of abnormal weldng e..rea.: or veltage.

(b)

Mapede Partide Inspec-Jon and Ultrasonic Testing:

No cracks were found by magnetic panide inspeedon. _

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1 Ultrasonic ~ inspection indicated the presence of nine f

cracks in the weld root area, ranging in length from i to 11-1/4 inches.

(c)

Maco-Sectioning:

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Maco-sectioning revealed that the initial sub are passes I

had fully penetrated the hand welded root pass.

The sketch contained in Figure 4 illustrates the degree of penetration present.

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2.2.4 Mock-Uo No. 4 The sub are welding on Mock-Up Nc, 4 was stopped after completion cf the first dual-head pass. When the sub are weld was. initiated, one head started erratically and then setted down after about four inches of welding. Therefore, this area j

was are gouged in preparation for hand weld touch-up prior to I

starting the second dual-head pass. The are gouging revealed

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the presence of a cack in the root area, approximately 1/4 inch below the surface, and at leas: 4 inches in lengd. The sub are veld was magnetic particle inspected in the are gouged

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area, and for a distance of abcut 6 inches down stream from the are gouge. This revealed that the cack did not penetrate i

through to the surface of the sub are weld. After magnetic par:Icie inspecting this area cf the weld, a decision was made to discontinue sub are welding and explore the joint by maco-l sectioning.

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Three maco-sections were made; in the are gouged area, 6-3/4 inches down stream from the are gouged area, and 13-1/3 1

incnes down s: eam frem the are gouged area. At 6-3/4 inches down stream from the are gouged area there was no evidence of the crack.

At 13-i/8 inches down stream, the c ack reappeared.

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2.2.8.1 Curren and Voltare Charu 4

The chart covering continuous recordng of 11 t

minutes, 40 seconds of actual are time revealed no evidence of abncrmal welding current or voltage.

2.2.4.2 Macro-Sectioning Macro-sec.icning revealed that the initial sub are passes had fully penetrated the hand welded root pass. The macro-see:!ons showed that 100% of the root pass weld had been melted when the initial dual-head sub are pass was made.

The sketch c=ntained in Figure 5 lilustrates the degree of penetratien which occurred.

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-..-..... Inte cretation cf the Results Obtained frem the Werk Cemoleted Under _

c Par: A The work c=mpleted in Par: A censisted of the making and evaluatien cf

1. cur one-of-a-kind test articles. One is a very small sample size, and there are risks e.ssociated with any attempt to draw definite conclusiens frem a sample of only one. These risks not withstanding, the results obtamed from the work completed in Par: A appear to indicate the following:

(1)

Raising the preheat /interpass/ pes: heat temperature to 300 F will not eliminate the sub-surface cracks, ner reduce their incidence.

Includng the werk reported in References (2) and (3), as-well-as the werk covered by this report,1: has been demonstrated tha: the sub-surface cracks have been produced at preheat temperatures cf (a) ambient temperan:re, (b) 200 F and (c) 200 F.

(2)

Changing the composition of the welding wire to the lowes: har::-

enabill:y c:mpesi:len accep:chie uncer ASME Specifica:icn 3FA l

' 23 will net eliminate the sub-surface c acks.nor reduce their incidence.

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(3)

Preventing deep peneraden cf the hand welded rect pass will reduce the incidence of the sub.sudace cracks, and may even completely eliminate these defects. This can be accomplished by increasing the number of hand passes made befcre commencing sub are welding, and by reducing the welding curren: used on the initial sub are passes..

l 1

(4)

NCR No. 77 (Reference (1)) is incorree Major variations in

~

welding current played no role In the inidation of the sub-surface c acks which are covered by the nenconformance described in NCR No. 77. There were no abnormal current varia:!cns produced when the River Bend corner juncdon tee joints were welded, in conformance with Welding Procedure 302N, using the DART 2108 automade welding machine.

(3)

Repair cf sub-surface c acks in existing comer june:!cn tee welds need. not be done by a spd repair procedure incorperating requirements for preheating prier to are gouging, plus require-

, ments for preheat /interpass/ pest heat tempe.a:ures of 300 F er -

higher.

Repeur may be accomplished using exis:ing Graver Welding Precedures 305N and RF-1 (Reference (6) and (8), res-pec:ively).

Discussien of the Resuits Obtained frem the Werk Cemeleted Under 2.4 Par-A The sub-surface c acks, which are covered by NCR No. 77 (Reference (I)) and 111ustrated in Figure 1, are probably the resui ef a solidification phenomenon, related to the convergence of. two sciidification fren:s.

Crsver 7elding Precedu e 302N "Os for an elecrede spacing (relative dis:ance be:-deen the tips of :ne :ve electodes, measured in a direc !cn par 11e1 to the diree.icn 'ef rave!) cf 1/21.ch :c 2 inches. I: is -'-

Graver shop pracdce to se: this distance befere star:ing a series of r

1 l

I welds, and leave it fixed throughout the series. In the case of the welds l

made on Mock-Ups No.1 - 4, the spacing was set at approximately 2 inches when the welds were made on Mock-Up No.1; and it remained at this distance when the welds were made on Mock-Ups 2 - 4.

l The position af the elec= ode with respect to in orientation relative to t

the center-line of the weld joint is not specified in Procedure 302N. It is Graver shop practice to set this positlen, before C.e initiation of de first dual-head sub are pass, based on a visual check made by the operater, and his judgment regarding proper positiening. As subsequent j

passes are made, the position is checked prior to initiating the weld, and i

adjustmenu are made.

t Differences in elecrode pcsitien probably account der the fact dat en Mock-Up Nc i the initial sub are passes did not ful!y penerate the

[

hand welded root pass, while on Mock-Ups 3 and 4, the initial sub arc passes did fully penetrate de hand welded root pass.

It may be possible to prevent the initiatien of de sub-surface cracks by i

proper adjustment of elecrode position, as desc-ibed in NCR No. 77.

However, elecrode pcsition is not an essential variable identified in

(

i Section IX of the ASME Boiler and Pressure Vessel Code. Furthermere, elecrode position is very difficult to identify quantitatively, and almest impossible to inspect ac=.trately.

i In order to attempt to con =cl electrode position, 0.nd thus prevent de

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initiatien af the subsurfac= cracks, it would be necessary to define values for dimensions @ through @, shown in Figure 6, and inspect to verify adherence to these values prier to initiation of the initial sub are pass.

This would. be very difficult to accomplisit Angle @, in j

particular, would be virtually impessible to conrol, since it is influenced by both tne wear en the bere of tne centac: ne=le anc tne amount of welding wire left en the spoci.

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CONTACT N o?iLE i

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For the abova rcasons, tha approach reflected in Mock-Up No. 2 is probably the only practical method that can be used to prevent, or i

minimize, the initiation of sub-surface cracks when corner junction tee joints are weided using Procedure 302N and the DART 2103 dual-head f

submerged are automatic weiding machine. This would involve changing Weiding Procedure 302N to require that at least four hand passes be made prior to initiation of sub are welding, plus reducing the current used on the initial duaj-head sub are pass by at least 100 amps.

2J Work Comoleted Under Par: B i

2J.i Ult asonic Testing of River Bend Unit 2 Corner Junction Tee Welds i

i i

Four Unit 2 corner junction tee weids were ultrasonic tested, using dual 60 transducers, to inspect for the presence of sub-j surface cracks in the rect area of the joint. The results of this testing are summarized in Table 1.0.

2.5.2 Reoair Welding l

L The three c ack indications in the comer junction identified as 3-E30 (see Table 1.0) were removed by are gouging. The local f

area in the vicinity of the indication was preheated to a minimum temperature of 300 F prior to are gouging.

i The are gouging was interrupted when the indications became i

visihie. Two of the indications appeared to be slag, although this, was not verified The third. Indication had more the-appearance of a c ack than of slag.

i Two of the three defect cavities were rehaired by hand we!d-

[

ing. One was repaired using a minimum preheat /in:erpass/pos, heat temperature of 300*F.

The other was repaired using Graver We! ding ? ocedures 305N (Reference (6)) and RF-i (Reference (S)).

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TAnl.E 1.0 ItESULTS OF ULTilASONIC TESTING Ol illVi.It 11gND UNIT 2 COltNEll JUNCTION TEE WELOS USING DUAL. 60 TilANSDUCEllS 8

Crack Indications in the floot Area of the Joint Identification Length of Number Length Total No.

. Total Lgth.

Total Lgth.

% Total of Unit 2 Corner (Inches) '

of Indica-of all Ind.

of all Ind.

Cor. Junct.

Corner Junct.

Junct. Weld tions In Cor. Junct.

Divided by Lgth. Occupied That was Ul (Inches)

Lgth. of Cor.

by Indications Inspected ed Junct. Inspect-3-E30 123 I

i 3

3-1/2

.028 3

2 1-1/2 3-E30 178-l/2 2

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3 6-3/4

.038 4

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1-3/4 I

2-1/2 6-30 177 1

3 2

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.047 3

1 5-l/4

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22-E30-1 177 3

1 10 21.5

.121-12

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3 8l 1

5-l/2 1

6-l/2 Total length of weld that was UT Inspected = 655.5 Inches Total length of all o ack Indications found in the root area of the joint = 40 Inches l'er cent of total wel.1 length (all four corner junctions) occupied by crack indicatlpns in the root area of the joint = 6.1%

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After completing the repair welds, they were magnetic par-J-cie inspec:ed and ultrasonic tested. No crack indications were found in either repair weid.

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3.0 RETERENCES f

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t (1)

Graver Nenconfermance Report (NCR) No. 77, dated 5/22/79 (signed eff j

on 6/27/79)

I (2), Graver Telding Procedure Sp<.ificaden No. 302N i

l 1

(3)

Graver report dated 7/2/79, Tide: Reeert en Examina-Jen cf Corner Junctien T-Telds & Stiffener Assernblies CSS. River Bend Uni: 1 PD No. RBD-294 i

'(4)

Graver report dated 10/25/79,

Title:

Cause-and-Cer ec-ive-Aeden Analvsis Conce ning Sub-Sudace Defects Found in River Bend Corner i

Junction Tee Telds

' (5)

Supplement No. I to Reference (4), dated 11/5/79 l

P i

(6)

Grave-Welding Precedure Speddication Nc. 30$N,

Title:

P-ocedure r

Soecificatien for Shielded Metal Arc Welding (7)

Draft # 1, dated 10/30/79,

Title:

Plan Coverinz Additional Werk Cen-l cerning Sub-Sudace De#eca Found in River Bend Corner Junction Tee j

7 elds (3)

Graver Welding Precedure Specifica:icn Ne. RP-1, Tide: Procedure for l

7 eld Recair of Base Metal j

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..-,4 85 - Y G/f l

METALLURGICAL INVESTIGATION r-River Bend Units 1 and 2

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Containment Corner Junction Weldment m

I GULF STATES UTILITIES COMPANY Beaumont, Texas l

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I January 1980

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J.O. 12210 I

Prepared by:

Approved by:

T O

l{ LY R. P. Indap A. W. La'tti MaterialsEngin}eering Assistant Division Manager

}

Materials Engineering i

L l

t Nuclear Document Centrol l

STONE & WEBSTER ENGINEERING CORPORATION Cherry Hill Operations Cente" JM416 FSO Cherry Hill, Nev Jersey

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METALLURGICAL INVESTIGATION River Bend Units 1 and 2 Containment Corner Junction Weldment i

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SUMMARY

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This report describes the metallurgical investigation undertaken to determine the cause of cracking in River Bend Units 1 and 2 containment f.

shell to mat embedment plate tee veld (corner junction). This in-vestigation was also undertaken to determine if a proper metallurgical structure exists for the weld and its heat-affected zone if it were "d

decided to simply remove the cracks and use the remaining weld.

It was I

determined that the crack was actually a centerline linear shrinkage-voids, interconnected by fine cracks, which occured during solidifi-cation of the undesirable weld nugget or bead shape deposited at the root.

If the defect is removed, the remaining weld material is metal-lurgically acceptable to the ASME Section III, Class MC Code requirements.

INTRODUCTION The corner junction assembly is designed and fabricated to ASME Sec-tion III, Class MC, 1974 Edition.

It consists of a 1 1/2-inch thick embedment plate made from SA-516 Grade 70, electroslag recelted, nor-malized carbon steel welded to 1 1/2-inch thick containment shell plate, made from SA-516 Grade 70 normalized carbon steel, roll bonded with L

stainless steel Type 304L cladding.

The shell plate was solution annealed at 2,025'F and then normalized at 1,650*F.

Figure 1 shows the weld joint detail design.

A single root pass was made with shielded

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metal are welding (SMAW) using a 5/32-inch diameter, E7018 electrode.

The remaining weld was completed with submerged arc welding (SAW) pro-cess by employing twin electrodes. The equipment used consisted of a DART 2108 automatic welder made by Ogden Engineering Corporation with Lincoln power source. Attachment 1 gives the welding procedure used by Graver Energy Systems to make this weld.

i

[

The completed weld was examined ultrasonically in accordance with ASME Section III, NE-5000 requirements.

The original examination was per-formed by a 45-degree angle beam, and the weld was found acceptable.

Subsequently, it was identified that the technique used was inadequate and that the weld must be reexamined by a 70-degree angle beam as a minimum.

This technique showed that the weld root contains planar indications.

Exploratory grinding and air-arcing confirmed that these indications were the result of a crack-like linear defect in the weld metal root area.

Sections representing the defective weld root area and sound weld were cut from a Unit 2 assembly (No. 3E30-1) for this investigation.

The samples were sectioned as shown in Figure 2.

Section 2 contained root area indications, and Section 1 had a sound weld based on ultrasonic examination.

The f ollowing tests and examinations were perf ormed f or this investigation:

it e

F l

1.

Macroscopic and metallographic examination of weld metal, base metal, and heat-affected zone (HAZ).

2.

Scanning electron microscopy of defect surface.

I 3.

Microhardness survey of defective weld.

4.

Charpy impact of weld metal and heat-affected zone.

i S.

Chemical analysis of the following:

"4 a.

Weld metal near defect.

I b.

Sound weld metal in weld beads away from defect.

i c.

Base metal containment shell plate.

i d.

Base metal embedment plate.

Results of Macroscopic and Metallographic Examination Figure 3 shows a polished and etched cross-section specimen containing i

the defect in the root area.

This specimen shows all weld beads.

The SAW pass in the root area was deposited from both sides of the shell

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plate and forms a single large bead, approximately 1 inch deep by 1/2 inch wide with a centerline defect.

This bead remelts and consumes

~

part or all of SMAW bead.

Figures 4A and 4B show the microstructure near the defect. The microstructure consists of boundary ferrite (light area),

aj acicular ferrite, and carbides (dark etched) (References 1 and 2).

Figure 5 shows the weld metal metallurgical structure away from the root, which is the same as the weld metal structure near the defect.

Figure 6 shows the heat-affected zone in the shell plate. The structure consists of prior austenite grain boundaries surrounding bainite colonies.

Figures 7A and 7B show the base metal structures which are ferrite i

(light areas) and pearlite (dark areas).

These metallurgical structures show expected conditions and are considered normal.

Scanning Electron Microscopy The specimen crack-like defect was opened to expose its surface.

Figure 8 shows the defective surface.

Figures 9 and 10 show this surface as viewed by a scanning electron microscope.

In Figure 9, the surface topography is shown as globular and not fibrous, which confirms a welding-related shrinkage solidification defect.

Microhardness Testing Figure 11 shows the locations where microhardness readings were taken.

Table 1 lists the results of the microhardness survey; the hardness values are within expected values in all areas.

4

1 i

I Charpy Impact Testing l

i Figure 12 shows locations at which Charpy-vee notch (Cv) impact specimens r

i were taken. The Cv testing performed in the embedment plate was a p

through-thickness direction test. The specimens taken from the heat-j affected zone (HAZ) were oriented in such a manner as to include as much of the HA2 as possible, as required by NE-4334.2. The results of Charpy tests are given in Table 2.

A ASME Section III, NE-2300, acceptance criteria require a 20 ft/lb energy value at 30 F less than the lowest service temperature.

Initial testing I

~

temperature was 0 F, which is 70 F below the lowest service temperature.

Specimens which had unacceptable Cv values at 0 F were retested at 40 F I

to represent actual code requirements, and all Cv values were found to be g

acceptable.

8 Chemical Analysis 3j The chemical analysis results shown in Table 3 are typical for the b'ase materials, wire and flux combination used.

j DISCUSSION u

Figure 3 shows that the crack-like defect is located approximately at f

1 the center of the first SAW passes.

Figure 4A shows that the defect L

consists of a series shrinkage-voids connected by the fine cracks. The

[

appearance of the defect can be understood by considering the progress of solidification of the first SAW passes.

5 I

~

Solidification of molten weld metal due to the quenching effect of the l

base metal starts along the sides of the weld metal and progresses inward by growing columnar grains. The last liquid metal to solidify lies in a plane through the centerline of the weld.

If the weld depth is greater than the width of the face, the weld bend surface usually solidifies prior to center solidification.

This prevents flow of liquid weld metal to the center to compensate for liquid to solid shrinkage and causes centerline shrinkage-voids.

Further, the shrinkage stresses rupture or 3

crack any solid weld metal connecting these shrinkage-voids, as shown in

~

Figure 4A.

t The scanning electron microscopy examination of the defect surface showed l

the globular topography interdendritic structure, which indicates that the defect was shrinkage-related, and occured during solidification of j

the weld nugget or bead.

It should be noted that the observed root weld centerline defect is only m

in the first weld pass.

Subsequent passes have proper weld nugget or bead shape and do not have centerline indications or defects.

l i

L.

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i To preclude this type of defect in SAW's requires that neither the depth nor the maximum width in the cross section of the weld metal deposited h

in each weld pass shall exceed the width at the surface of the weld-I d

(Reference 3).

{

The metallurgical structures observed in the weld metal HAZ's and base f

materials are all considered normal and acceptable.

"**' "d"' " """ "" "" *""* ""* ""* "" " ""* " """

I, the weld metal, plate HAZ's, shell plate, and embedment plate.

The Cv testing results indicate that weld metal has more than adequate toughness in all areas.

The Cv specimens from the HAZ show lower toughness than base metal; however, this is considered normal for the l

welding process employed and materials used.

CONCLUSIONS The crack-like defect in the containment corner junction weld consists i

of centerline linear shrinkage-voids interconnected by fine cracks.

This defect was caused by undesirable bead weld nugget or bead shape deposited, due to either insufficient SMAW passes, too high input in SAW initial

}

passes, or insufficient staggering between opposing SAW arcs. Evidence l

of unacceptable metallurgical structure was not observed for properly solidified weld areas.

i 1

i Removing the root defect and rewelding with proper welding parameters l

can be employed to restore the containment corner welds to ASME Section III, i

3 Class MC code requirements.

t 1

2-RECOMMENDATIONS

{

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In SAW, bead shape control is an important factor for making sound welds.

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Special attention should be given to this during development of the

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welding procedure. Neither the depth nor the maximum width in the cross i

section of weld metal deposited in each weld pass should exceed the width at the surface of the weld pass. Weld bead dimension should be checked and measured by sectioning and etching a sample weld.

l IL When the width of deposited weld metal exceeds 1 inch, as in the multiple electrode SAW that was employed, the arcs should be separated to properly i

'j control solidification and crack-free welds. Another improvement would i

be to separate the electrodes completely by more (possibly three minimum)

SMAW root passes, and then back gouge before the twin electrode SAW process is employed.

t REFERENCES I

1.

Glover, e..

G., et al. Weldinc Journal, September 1977, p. 267.

l i

2.

Choi, C.

L.,

and Hill, D.

C., Weldine Journal, August 1978. p. 232.

f, l

3.

AWS D1.1, Structural Welding Code, 1975, American Welding Society.

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CONTAINMENT _i l n

N MAX CLADDING SHELL PL 8

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FIGURE 1 CORNER JUNCTION L

WELD JOINT DET All t

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Embedment Plate I

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• Distance from reference end of the assembly in inches i

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SECTION 1 - SECTION CONTAINING SOUND WELD USED FOR CHARPY f

IMP ACT TEST SPECIMENS.

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SECTION 2 - SECTION CONTAINING CR ACKED WELD USED FOR METALLOGRAPHY, HARDNESS AND CHEMICAL AN ALYSIS SPECIMENS.

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FIGURE 2 CONTAINMENT CORNER JUNCTION T-WELD $ECTION USED FOR MET ALLURGICAL INVESTIG ATION i

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FIGURE 3 CROSS SECTION SHOWING DEFECT IN THE ROOT AREA I

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FIGURE 4 A CENTER PORTION OF THE DEFECT ALONG WITH TWO DIAMOND PYR AMID H ARDNESS INDENTATIONS t

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FIGURE 4B WELD METAL MICROSTRUCTURE NEAR DEFECT. (THE MICROSTRUCTURE CONSISTS OF BOUNDARY FERRITE, ACICULAR FERRITE, AND CARBIDE.)

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FIGURE 5 MICROSTRUCTURE IN THE SOUND WELD BEADS I

AW AY FROM DEFECT. (THE MICROSTRUCTURE

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CONSISTS OF BOUND ARY FERRITE, ACICUL AR I

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EMBEDMENT PLATE I

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LOCATION NO.

IDENTIFICATION 1

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1 BASE METAL - CONTAINMENT SHELL PLATE l

l 2

HAZ - ABOVE SAW LARGE BEAD 3

WELD METAL - S AW LARGE BEAD 4

H AZ - BELOW S AW LARGE BEAD 5

B ASE MET AL - EMBEDMENT PLATE 6

H AZ - AW AY FROM ROOT IN SHELL PLATE 7

WELD METAL - AW AY FROM ROOT PLATE 8

H AZ - AW AY FROM ROOT IN EMBEDMENT PLATE FIGURE 12 SKETCH IDENTIFYING LOCATIONS OF CHARPY V-NOTCH TEST SPECIMENS i

w

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TABLE 1 i

RESULTS OF MICR0 HARDNESS TESTS Hardness

}.

Location Rockwell Hardness Scan A B Scale Vickers No.

.f 1

Base Metal 63.5 114 I

2 HAZ 92.5 207 3

HAZ-98.0 241 F*

4 Weld Metal 100.5 258 l

5 Weld Metal 99.5 249 i,

6 Weld Metal 94.5 219 3

7 HAZ 102.5 271 l

8 Base Metal 94.0 216 i

Sean B 1

Base Metal 88.0 184 l

2 HAZ 92.0 204 i

i 3

HAZ 100.5 258 r

j-5 Weld Metal near Defect 96.5 230 4

Weld Metal 97.0 234 l

6 Weld Metal 97.0 234 i

i 7

Weld Metal (SMAW) 91.0 198 i

t-8 HAZ 103.5 280 t

9 HA2 96.0 230 l

10 Base Metal 90.0 195 e

l 5

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TABLE 2 I

RESULTS OF CHARPY IMPACT TESTS 1

i

~

Temoerature 0 F Temperature 40 F

[

Energy in Energy in Location ft/lbs Average ft/lbs Average 1

47.5 34.0 39.0 i

4 35.6 i

2 27.0 28.5 1

21.5 21.7 23.0 27.1

{

16.5 30.0 l

3 26.5 37.5 41.0 j

59.0 4

15.5

'23.3 i

10.0 14.5 25.8 26.2

}

18.0 29.5 i

t 5

23.0 38.0 18.0 17.7 39.0 40.0 12.0 43.0 6

14.0 51.0

{

18.5 17.5 45.8 52.6 j

20.0 61.0 1

7 50.0 1

57.0 54.8 57.5 8

57.0 32.3 40.4*

i 32.0 i

i

• Specimen orientation caused notch to extend in weld metal.

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TABLE 3 l

RESULTS OF CHEMICAL ANALYSIS 6

Location of f

Sample C

Mn Si S

P Ni Cr Mo Weld-Metal at an r

near crack 0.13 1.33 0.19 0.010 0.005 0.091 0.052 0.19 l

t Weld Metal I

away from crack 0.09 1.48 0.17 0.013 0.005 0.072 0.047 0.37

[

t l

Embedment Plate 0.22 0.63 0.22 0.009 0.005 0.13 0.06 0.07 i

Containment Shell Plate 0.24 1.00 0.18 0.019 0.005 0.18 0.09 0.04 I

i C - Carbon

(

r

.% - Manganese Si - Silicon S - Sulfur P - Phosphorus l

N1 - Nickel r

Cr - Chromium Mo - Molybdenum i

~

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l 6

ATTACIDENT 1 l

a Graver Energy Systems Welding Procedure Specification 302N e

'e L

s h

e r

im b

I i

i E

~ W T6 ^ ~ ~ "

scnu alalIUM. UNIT M 2 r

wuveu p

GULF STATES UilLITIES j

1 WEST FEllClMIA PARISH, LA.

ORDER NO. 61060N Page 1 of 5 J.O. No. Jame.12330 P.O. No. 219 710 C056

~

r3 i 1 A\\/ E A TAN K S. M F G. C O.

I ^TT**"

1 I WF.lDIlC PTOCEDURE SPD'IFICATION NO:

302N SUPPORTING P.O.R.

S-118B Rev. 1-1 3-14 k6 REVISIONS:

Rev.

2-9 77 4

3 X

JOINTS PREHEAT YES NO Grcove Design:

Double Bevel Groove Welds Preheat W rature 1" -200*F.

l 4

1" -100*F Backing:

- 350'F Other:

Interpass Tenperature Preheat Maintenance None FILLER IMTERIAL U

SMAW SAW

]

' F No.

4 Other Mer

~~~

A No.

Other Spec.'No.

5.1 (SFA)

(Ah'S) b Class E7018 Linde #40 MCAL GWNSTICS L

Electrode Size 5/32" dia.

1/8" dia.

Current DC (E-DC)

Electro:ie/ Flux Composition Lincoln 860 Flux-P61arity Reverse F-72 Linde #40 SMAW SAW SMAW SAW Idil -

10103A Ws 14 0-185,4 0 0-65(Dolts 20-24,26-Q J Other Type Mil-B4 i

(range)

(range) 10-20 IPm

' BASE FETAL dW 1

P No.

Group 16.

Other t

to 1

2 ane & Wess er I

p 30, Group No.

POSITICN Engm:enng Cor;::rattn hy;-(7.,gerg-gon t;al (2F)

- Thickness Range 5/8" 1/2" Position of

, ],,;,',j,j b unA::tPTAstr

, Otler Weld Bead, Thickness not to exceed g

. ; c's

-a pOSanD HEAT TFERENT r1nm x

j Yes No 1.0. N Lon pe.,.l.2L/O %

I N

progress:.

s Temperature

-,-r

_7

~

l DATL9lM4"J'7 l

[ 'ime

[au-4rO~y M 1

, Mer i

This docume..

1_...' the data contained here.

in. or herewith. is not to be reproduced, L

used, or disclosd in whole, or in par., to anyone without the permission of Graver l-Tank & Mig. Co, I

r G A AVJE A TA N K S. M F G. C O.

PRDCEDURE SPECIFICTION NrJMBER: 302N l,

Page 2 of 7

' TECFliICUE GAS String or Weave Baad String Shielding Gas N/A T

Initial & Interpass Cleaning

Deslag, I;

Grind or Power Brush Flow Rate N/A Arc Air'Goug or Purge or Backing N/A L-142thod of Back Gouge I

Grind Multiple Multipass or Single g

side Multiple or Single Electrode Multiple Shd N/n.

See Attached Sketch Cup Size Sheet No. 610B680 3/4" 1/4" Cbntact Tube to Work t

Retainer used - None 1

Elec. spacing - 1/2" to 2".

I R E M A R K 5: The welding shall be done using single mounted welding heads, operating independently on either or both sides of the weld joint.

Rev. 1 Requalified in the horizontal position using multiple electrod:

Rev. 2 9-1-77 Corrected electrode type.

We certify that the statements in this record are coirect and that the test welds were l

prepared, welded and tested in accordance with the requirc: rents of Section IX of the ASME Ccde 1974 Edition.

GRAVER TAMK & MFG. CCMPANY An Aerojet-General C m v

(_\\%,M__-

BY o

L DATE dD a, (<;-. tA i 6 6

Psge 3 of 5 a'

J PFCCEEUPS GJALIFICATION REODRD DtdE: 10-14-76 7

PMS CUALIFICA"'ICN PZCO2D N2EER: S-ll8B WPS IR SER: 302N I

D A AV E R TA N K S. M;:G. C C.

[

WELDING PPES(ES): SMAW/SAW TYPES: Manual and' Automatic 1

JOIhTS (10-402) y BASE ?CIAL (G1-403)

[

Material Spec.

SA516

~k*

70 Type or Grade

,?

7 gg 45 1 Gr up 2 1 Group 2 e

P lb.

p I

j 4

Thickness 1~1/4" g

Diareter j

g Other N7 FIIlzR ICIALS (Gi-404)

SAW SMAW POSITICN (G1-405)

Weld Matal Analysis A l'b.

l'

' Position of Groove Horizontal (2G)

Sire of Electrode 1/8"E 5/32"9 Weld Progression N/A 4

NM' #-O Filler Metal F. No.

~~

5.1

~

SFA Specification E70.18 PREHEAT (Gi-406)

AI;S ' classification i

Linde #40, Type Mil-B4 P:deheat Tenperature O'ler Mil-E-18193-A g

Lincoln 860 Flux-F-72 Interpass Te p ture 350a MAX l

Other i

POS'IWELD HEAT TREAre,T (Gi-407)

GAS (Gi-408)

Tcreerature None Type of Gas or Gases N/A Ti: e Chrposition of Gas Plxture Other Other E M.ICAL CHAPA MTICS (Gi-409)

TE3NICUE (Gi-410)

Current DC

. String or Weave Dead String Reverse

!^

Polarity _ SMAW / SAW SMAW / SAW Oscillation

~

Anps 14 0-18 5, 4 0 0, 6 5 0/olts 2 0- 2 4,2 6-3 3 Single or.khltiple Electrodes Multi.ple 10-20 IPM (2)

Travel Speed Other other 1.

Shielded metal arc root

(

pass not to exceed two (2) passes

3. Weld bead thickenss not to excee 1/2 inch.

4. Elec. spacing - 1/2 tc 2"

l b

- pmune -

omvw-mmr-----

icymurumumm "yc,wn j ' DRTO,'IiG NO: 610B680 E1 10/14/7( U$SNf$ift19_Eple N$c$90aeg sr

~

DATE:

(2 9-1-77 Corrected electrode type

~

c. A A\\/E A TAN K S. M P G. C O. !3 4

SPECIFICATIO410.

302N j5 T-5/8" 3/16" max.

T >.1-3/16" 1/2"

.c w

I f---

J

\\

d 48" 3 *

.1/16,'

45 I

45' 35*

b, 1

.1 2:.

Is m

1 t._,, 0 "- 3/3 2 "

}3/16"+1s Notes:

1. Lincoln 860 Flux

2. Linde No. 40 Wire

3. Nose f_ 1/16" First Welded Side (Lead Elec)

Second Welded Side (Trail v1 M Fill-Pass Elec.

! Fillet Elec Pass Speed T et Site 170.

Dia.

Volts Current. Sise Dia.

No.

7olts Current I.P.M 5/8 3/8" l-2 1/8" 26-29 400-500 l 3/8" 1/8" l-2 26-29 400-50C 10-14 a

}

3-4 26-29 400-500 3-4 26-29 400-50C 16-20 1.

1" 3/8" 1-2 1/8" 26-29 400-500 y3/8" 1/8" l-2 p6-29 400-50C 10-14 3-5 26-29 400-500 l 4-5 h6-29 l400-50d 16-20 l

l 1*

5/8" 1

5/32" 22-24 140-175 l

, 1/4 2

1/8" 26-29 450-525 5/8" 1/8" 2

26-29 500-55C 10-16 3-6 ll/8" 29-29 450-550 l 1/8" 3-12 26-29 aso-sse 1 A - 9.0.

1*

5/8" 1

5/32" 22-24 140-175 1/2 2

1/8" 26-29 450-525 5/8" 1/8" 2

26-29 500-550 10-16 3-12 1/8" 26-29 450-550 1/8" 3-12 26-29 450-55b 16-20 1

\\

Notes:

1.

4anmum Interpass Temperature 350*

2. Number of fill pass may vary due to fabrication and fit-up.

3. Manual root pass shall be made with E7018, 5/32" dia. elec.

4. The reverse side of the root pass shall be arc air gouged or groun to remove excessive weld metal and cleaned by wire brushing.

.. oo = m ag Paga 5 of 5 3

i i

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J

~

... PROCEDURE QUALIFICATION RECORD i

(

TENSILE TEST (QW-l'50)

ULTIMATE ULTIMATE CHARACTER OF l

SPECDIEN TOTAL LOAD UNIT STRESS FAILt*EI &

l NO.

. WIDTH THICKNESS AREA LB.

PSI LOCATION l

7 1

.755 1.527 1.15::

95,000 82,400-Base Metal j

6

.780 1.530 1.19:

97,500 81,700 Base Metal HAZ i

7 r

j CUIDED BEND TESTS (qu-160) 1 l

TYPE AND TYPE AND FIGURE NO.

RESULT FICURE NO.

RESULT QW462. 2 (A) 2 Satisfactory QW462. 2 (A) :

Satisf actory -

QW4 62. 2 ( A) 4 Satisfactory QW462.2(A)5 Satisfactory l

tt l

1 t

TOUCl! NESS TESTS (QW-170)

SPECLMEN NOTC11 NOICH' TEST IMPACT

'(

No.

LOCATION TYPE TEMP VALUES

~ LATERAL EXP.

DROP WEIGHT I bnt.AR PML5 b KE.AK

' W EM.AK 1

CW Vee

-35 28 25%

29 2

CW Vee

-35 38 30%

41 r

L 3

CW Vee

-35 30 30%

31

)

t 1

HAZ Vee

-35 40 35%

42 2

BAZ Vee

-35 43 40%

45 u

3 HAZ Vee

-35

,36 35%

37 i

Type of Test.

t OTHER g

• FILLET WELD TEST (QW-180)

Result - Satisfactory N/A penetration into Parent Metal

{

(yes, No)

(yes, No) l Type & Character of Pa11ure.

Hacro-Results l

Welder's Ncme R. Leadingham 1022 Clock No.

gg,,p po, oval 5 j

Tests Conducted by Graver & M.R.L.

Lab Test No. S 118 B T.

Michniewic-l per We certify that the statements in this record are correct and that the tests 1

f welds were prepared, velded and tested in accordance with the sequirements:

of Section IX of the ASME Code 1974 Edition.

t Signed

[ \\(s.D u

)

Date

/ O-M- 7 6 By hd. t [ M G A AV ER TANK & MFG. Co.

I I

f