ML20087F808

Co Insp Rept 50-219/68-09 on 670929-681104 of Reactor Pressure Vessel Repair Program to Determine Readiness of Reactor for Operational Licensing

ML20087F808
Person / Time
Site:	Oyster Creek
Issue date:	01/06/1969
From:	Harold Denton, Reinmuth G US ATOMIC ENERGY COMMISSION (AEC)
To:
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ML093631134	List: ML18010B195 ML20087F806 ML20087F808 ML20087F815 ML20114E363 ML20114E376 ML20114E393 ML20114E412 ML20114E468 ML20114E472 ML20114E487 ML20114E503 ML20114E514 ML20114E518 ML20114E524 ML20114E628 ML20114E678 ML20114E702 ML20114E729 ML20114E765 ML20114E777 ML20114E794 ML20114E836 ML20114E844 ML20114E871 ML20114E876 ML20114E883 ML20114E887 ML20114E896 ML20114E916 ML20114E941 ML20114E963 ML20114E971 ML20114E988 ML20114E999 ML20114F029 ML20114F032 ML20114F049 ML20114F076 ML20114F121 ML20114F142 ML20114F153 ML20114F189 ML20114F202 ML20114F209 ML20114F221 ML20114F260 ML20114F273 ML20114F279 ML20114F282 ... further results
References
50-219-68-09, 50-219-68-9, NUDOCS 9210120189
Download: ML20087F808 (45)

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{{#Wiki_filter:-_- - f -f',,...s'. " 8. *.21 'i ....o .), - e, q7.' E U. S. ATOMIC ENERGY COW (ISSION l DIVISION OF COMPLIANCE i HEADQUARTERS CO Report No. 219/68-9 REPORT OF REACTOR PRESSURE VESSEL REPAIR PROGRAM Licensee: JERSEY CENTRAL POWER AND LIGHT CO. CONSTRUCTION PERMIT NO. CPPR-15 1 Time Interval Covered: September 29, 1967 - November 4. 1968 Number of Visitis : 30 Place of Visits: 26 to Oyster Creek reactor site 3 to Combustion Engineering, Chattanooga, Tennessee 1 to General Electric Co. San Jose, California Inspections By: G. W. Reinmuth N /~d 69 Reactor Inspector (Program Standards) (Date) Reviewed By: H. R. Denton / [ //4/// Chief, Technical Support Branch '(Date) Proprietary Information: None SCOPE The purpose of this inspection effort was to gather and report factual information relative to the repair of the Oyster Creek reactor pressure vessel; to evaluate the quality of the work performed; to determine that specified repair procedures were followed; and to witness final tests demonstrating that the vessel had.been restored to its original condition. These activities were a part of the Compliance program to determine the readiness of the Oyster Creek reactor for operational licensing. StH4ARY Extensive cracking of the control rod drive (CRD) stub tubes was experienced in the Oyster Creek reactor pressure vessel due to corrosion, stress assisted, intergranular attack. The stub tubes were manufactured from 304 stainless-steel and in the fabricated stat _e were in a fully sensitised condition. . Follow-up investigations disclosed that the sensitised 304 stainless steel parts of the nossle safe ends and a forged ring in the shroud support also had been damaged. In addition to the intergranular attack, welds attaching the CRD housing to the stub tubes, commonly referred to as the field welds, and the in-core flux monitor tube welds also were identified as defective. N %\\b\\'LoNB e c

) . sw. i O 3 0 . ) As a consequence of these events, an extensive repair program was under-taken to return the reactor vessel to a condition equal to or better than its original state. To accomplish the repair, all sensitized areas of the j stub tubes which would be exposed to the reactor environment were clad with -308L material. All sensitized material contained in the nozzle safe ends was either replaced or clad with 308L on both internal and external surfaces. I Since cladding of the shroud support structure was considered to be impractical, a redundant auxiliary _ support structure was installed as a corrective measure. Faulty field welds were completely ground out and replaced.In-core flux monitor tube welds were hand ground to a predetermined depth after which the removed weld metal was. replaced. From numerous observations of the work at the several repair stages, from examination of both intermediate and final test results and from record re-views, it has been concluded that the work was completed according to i procedure and is of an acceptable quality. DETAILS 1. Persons Contacted The following individuals were involved with the repair program and contributed information or aid to the inspectort General Electric Company E. A. Lees, Metallurgical Engineer D. C. Bertossa, Metallurgical Engineer W. R. Smith, Metallurgical Engineer T. F. Robinson, Metallurgical Engineer A. Hubbard, Manager of Materials J. Bland, Welding Engineer D. Tackett, Welding Engineer R. A. Huggins, Project Engineer D. Willet, Test and Startup Manager L. Koke, Resident Manager N. Strand, Resident Manager W. Hess, Startup Engineer R. C. Haynes, Startup Engineer H. Engelking, Lead Engineer-Supervisor W. Royce, Records Manager C. Buckner, Records Manager A. Dunning, Construction Engineer C. Smith, Construction Engineer L. Loeb, Q. C. Coordinator S. Naymark, Manager J. B. Graham, Washington Technical Representative J. Barnard, Manager W. L. Walker, Corrosion Engineer =-

.O iOF. 3.- ) R.'C. Holt, Testing Engineer I. R. Kobsa, Design Engineer; 3 S.:W. Taggart, Stress Analyst d D. Hackney, Metallurgist _ J.' McDaniel, Master Walder - ' L. Finney,- Welding Supervisor -A. Toule, Q. C.. Inspector y Mr. Cortez, Welding Supervisor Mr. Lindemann, Q. C. Inspector A. Tassona, UT Technician J. F. Cage, Project Engineer. S. G. Hall, Q. C. Site Representative (at CE) C. T. Ward, Engineer Jersey Eentral Power and Light Company L. Roddis,'Vice President, General Public Utilities G. H. Ritter, Vice President G. F. Trowbridge D. R. Rees, Project Manager T. McCluskey, Site Manager N. Nelson, Maintenance Foreman Mr. Kossatz, Maintenance Foreman I. Finfrock, Technical Supervisor F. Anderson, Welder D. E. Hettrick, Operations Supervisor Combustion Engineering W. B. Bunn, Metallurgist Consultant E. C. Chapman, Manager R. Lorenze, Manager R. L. Lumpkin, Stress Analyst J. W. Harper, Engineering Supervisor J. J. Barger, Engineer-D. Randolph, Metallurgist E. S. Proctor, Manager, Q. C. F. Hill, Stress Analyst T. M. Pierson, Metallurgist j Wayland Powell, Welder (at 0.C. site) P. Runion, Inspector (at 0.C. site) S. Baxtor, Inspector (at 0.C. site) R. Rockwell, Metallurgical Engineer 'i MPR Associates (JCP&L)(Consultants) L W. R. Schmidt p h r

r b' O 3 1r e II. Introduction A complete description of the Oyster Creek reactor vessel problem and the known considerations believed to have been factors in causing those problems are fully documented in the several amendments submitted by the licensee (Amendments 29, 35, 36, 37, 40, 43, 47). The substance of this report will be limited to documenting the observations of this in-spector in assuring that the vessel repairs were carried out as prescribed in the above amendments. There were two distinct types of problems experienced:

1) inter-granular corrosive attack on furnace sensitized stainless steel components; and 2) faulty welding. Since their correction proceeded in a sequential manner, without regard to cause, this report will also be categorized according to the specific repair work classifications.

To further clarify the several considerations involved in the vessel repair, a detailed chronological history of events and the inspector's activities are given in Attachment A. III. Bottom of Vessel Repair A. _ Initial Observations During the initial field hydrostatic pressure test of the reactor pressure vessel on September 29, 1967, a leak was observed by G-E construction personnel, to be emanating from the vicinity of stub tube 31-46. The leak was described as about a drop per minute. This inspector visited the site on October 19, 1967, for the first time and observed that the vessel was still full of water from the cleaning and hydrostatic pressure test. It was noted that the water was not clear. Furthermore, workmen were installing the storage pool liner plates inanediately above and surrounding the top of the vessel. No pro-tective cover was over the vessel. The possibility and probability of extraneous material falling into the vessel from this work was considered to be high and comments to this effect were made to Mr. Royce of G-E. The vessel was subsequently covered. Also, at this time, the entire south wall of the upper superstructure of the building was open to the environment. These observations are recorded for the purpose of documenting the construction environment to which the vessel was exposed and which may have been a contributing factor to the cause of the problem.

l O ] V. B. Detection and Evaluation of Problems On October 25, 1967, another visit was made to the site at which time the first entry was made into the vessel. Entry was accomplished by crawling through one of the five main recirculation system pumps, up the 26" recirculation system pipe, through a restricting orifice and into the vessel via the inlet nozzle. Tube 31-46 was dye penetrant tested at this time and a linear indication approximately 6" long was observed by the inspector and others at the fusion line between the Inconel shop weld and the stub tube on the { high side (furthest from vessel center). Minor dye indications, all con-sidered within code requirements, were also observed on the surface of the stub tube to control rod drive (CRD) housing weld, commonly referred to as ) the field weld. Since the linear indication was obvious, the assumption by all observers was that the leak must be at this location, probably caused by a lack of fusion between the Inconel shop weld and the stainless stub tube. Following this initial observation, additional selected tubes were dye penetrant tested. These tests showed similar indications in similar locations. As a consequence of these findings, all stub tubes were subsequently tested and of the 137 total, 108 were found with linear indications ranging from approximately " to 8" in length. All indications were on the high side of the stub tube with the longest indications on the outermost tubes, decreasing in severity in a progressive pattern toward the center of the vessel. Those tubes with no indications were located near the center of the vessel. Indications were also found in the field welds but were considered to meet code requirements and to be irisignificant at this time. To determine the nature and possible cause of the cracking, a limited grind-probe was performed on the lenker in the region of the observed indication. Removal of approximately 1/8" of the Inconel weld metal and 1/16" of the stub tube base metal did not disclose the direction of cracking but did succeed in reducing the length of the dye indication. As the probe grinding was inconclusive, a metallurgical sample was trepanned from tube 34-51 which showed a dye indication similar to that of the leaker. The sample was removed so that a section of the stub. tube, the Inconel shop wcld and a portion of undisturbed cracked area were con-tained within the sample. Microscopic examination of this sample disclosed the first evidence of intergranular corrosive attack which was subsequently confirmed by additional metallurgical samples. Reference should be made to Amendment 29 for details of the metallurgical examinations, the results and their interpretation. This sample also demonstrated that the Inconel shop weld was sound.

t. 6-The inspector and Mr. J. Chyle, welding engineer from Parameter, Inc., were at the reactor site on October 31 when this first metallurgical sample was removed. Even with good lighting, a 10X magni-fying glass, and knowing the precise location of the indications, direct examination did tot disclose a clearly discernible crack. Subsequent observation also by Mr. Chyle and the inspector by microscope at the CE laboratory in Chattanooga, Tennessee, confirmed the findings as documented in Amendment 29. Figure 1, page 22 of that amendment is an accurate view of the sample cross-section observed. Since the metallurgical samples showed the Inconel shop welds to be sound and the intergranular attack to be limited in depth, the field weld became suspect as the source of the leak. Further probe grinding of ] the field weld did in fact demonstrate that the leak resulted from a series of welding flaws, primarily lack of fusion and porosity type defects. For details, see Amendment 29, page 20. Further probe grinding of other field { welds indicated a general welding problem which was subsequently confirmed i by ultrasonic tests. With this evidence, G-E made the decision to remove and replace all field welds. With the identification of a basic welding problem, the Inconel welds attaching the in-core flux monitor tubes to the vessel also became suspect. Grind probing and dye penetrant tests confirmed that these too would require repair. Verification of the existence of a stress corrosion type problem led to more detailed and extensive evaluations of the probable causes. Among the efforts were stress analyses of the stub tube-housing design. These analyses showed that the short stub tube length inherent in the design resulted in the highest concentration of stress on the high side of the stub tube in the region of the observed attack. Furthermore, during shop installation of the stub tubes, excess weld metal had been applied and only minimal effort made to smoothly flare and blend the weld metal into the stub tube wall. These actions further reduced the effective length of the i stub tubes thereby accentuating the stress concentration in the affected area. { Following these preliminary analyses in early December 1967, G-E's initial repair plan was to increase the effective stub tube length by grinding out the excessive metal in the Inconel shop welds and smoothly flaring the transition area. All crack indications were also to be removed by grinding according to prescribed procedures. (See Ameniment 29, Figure 10, for geometry limitations.) At this time, Mr. Foley, stress analyst from Parameter, Inc., was requested by Compliance to accompany this inspector to Chattanooga, Tennessee, to review these considerations with CE design personnel. His findings agreed with those of G-E and CE in that increasing the stub tube length and flaring the weld would reduce stress concentrations by redistributing the stresses more uniformly over the length of the tube. I

U l Further dye penetrant tests tended to confirm that the area of attack was limited to the parts of the vessel fabricated of 304 stainless material which had become fully sensitized during the final stress relief. Additional indications were found on the stub tube walls at random loca-tions and generally unrelated to high stress points. Other indications were subsequently found on nozzle safe ends and on the shroud support forging. The extent of attack is described in detail in Amendment 35, Section III. Other tests in both G-E and CE laboratories were conducted in attempts to identHy the specific cause. Fu11 scale mock-ups were constructed by CE 6nd subjected to shop and field fabrication procedures. These mock-ups were observed at Chattanooga. These tests, the results and the conclu-sions are also described in Amendment 35. In essence, the basic conclusion reached was that all sensitized material would be clad with 308L stainless or replaced. Vessel repairs proceeded on this basis. As the need for a major repair program was now evident, preliminary steps were taken at the site to facilitate the work conditions. One of the five recirculation system piping loops was cut loose from the vessel to per-mit easier access into the vessel. Other dismantling work on the in-core 1 monitoring tubes was also performed. C. Field Weld Removal Hcving made the decision to remove the' original field welds and clad the stub tube surfaces, G-E and CE began development of custom tooling for veld removal, automatic weld replacement and automatic stub tube cladding. The progress of this development was followed by this inspector including demonstration of the welding machines on mock-ups. In all cases, the machines and the operators were qualified according to detailed prescribed procedures before production work was permitted in the vessel. i Initial efforts were made to develop two types of weld removal machines; one mechanical, the other electric arc. The electric are method was discarded after the device failed to meet the precision and speed re-quirements. Ultimately, a vertical milling machine was adapted to the job and was successfully employed in removing the welds and preparing the top of the stub tube to the proper contour for rewelding. (See Figure 3-1, Amendment 36.) Operation of these machines (two in number) was observed on three occasions. From these observations and reviews of the accompanying records, this inspector concluded that the operation was carried out in accordance with Repair Procedure RP-3-1 included as part of Amendment 36. l

L. 'l O l.- With the start of the repair work, access control procedures were put into effect to control the entry of extraneous material into the vessel. It was noted that during the machining operation, deminer-alized water was used to lubricate and cool the cutters. Oils were not permitted. Cleanup of chips and a hose-down of the vessel were performed at least once per shift. The diligence used by personnel in wiping material from their feet before vessel entry and continued use of cover-alls without periodic laundering were considered areas where tighter con-trol might have been practiced. D. CRD Housing Removal Access to the field and in-core monitor tube welds with all housings in p' lace was difficult or impossible because of the geometry of the vessel. This was particularly true toward the center of the vessel where the housings extended u'p into the vessel approximately 3-

feet, thus preventing workmen from reaching the subject welds. To permit con-tact work and also to provide space for the automatic welding machines, 79 selected housings were removed.

Removal of the housings was a relatively easy operation following the cutting of the original field weld. This weld, plus a close fit between the stub tube and the housing, holds the housing in the proper location and in alignment. To facilitate removal, the upper part of the housing projecting into the vessel was machined on the out-side diameter.060". Machining was accomplished at the same time as field weld removal using the same milling machine. Removal of the hy-draulic piping from the lower end of the housing was also required. The procedure followed for this work was as described in Amendment 36, RP 3-3. Removal of 79 housings permitted a number of additional obser-vations. Dye tests of the inside of the 79 stub tubes disclosed no intergranular attack on any of the tubes. Testing of two of these tubes was observed by this inspector. Some question was raised about the possi-1 bility of residual stresses in the shop welds if the stub tubes were " bottomed" in the machined socket into which the stub tube is set prior to welding to the vessel. Several of these were visually checked by this in-spector. Of those examined, all had a gap ranging from the width of a finger nail to 1/16". Removal of the housings also permitted additional ultrasonic tests from the inside of the stub tube. These tests did not disclose any cracking which had not been identified by the original dye tests. With improved access permitted by the housing removal, a ) second comprehensive dye test was undertaken for record purposes. These tests disclosed additional indications as well as more extensive indica-l tions in areas previously observed. (See Amendment 35, Section III for i results.) This new information raised the question as to whether the i 1 I t l

y a-F 1,. 4 ] J;. ; f cracking mechanism was continuing. G-E stated that the additional in-dications resulted.from the improved access which allowed better. testing techniques and that the experience achieved by the personnel in conducting ' O extensive dye tests resulted in more careful observation and more conserva-j tive interpretation of.results. From this inspector!s observations, a higher level of diligence was evident in the performance of the tests. E. Contouring of Shop Welds With CRD housing removal, actual repair operations commenced.. Contouring of the shop welds to increase the effective stub tube length to a minimum of 1-1/8" was perfo'rmed on a total of 68 tubes according to ) the procedure documented in Amendment 36, Repair Procedure No. 5. (Also, see Figure 3-1 for dimensional requirements.)' 1 The contouring was accomplished by use of a grinding wheel j -fixture which attached to the stub tube. The stub tube provided a firm j base for the grinding wheel as well as a fixed reference point to prevent i excessive grinding. Movement of the grinding wheel was manual within. the guides of the fixture. Work quality was examined on a sampla of 12 tubes and was; con-sidered satisfactory on the basis of dimensional e.easurements and the 'l finished contour surfaces. Dimensional records were maintained and dye tests performed according to procedure. 'l F. Preparation of Stub Tubes for Cladding Included in this phase of the repair was removal by grinding of' all intergranular attack indications on the stub tube walls; repair welding of the ground areas to restore the original contour of the stub tube; -polishing by light grinding of all the stub tube surfaces to assure a clean condition prior to overlay; a final dye test to assure that no indications-had been overlookd; and finally, cleaning with isopropyl alcohol. These procedures are documented in Amendment 35, RP 6-1 and RP 8-1. Each of these operations was observed at various times during a series of visits to the site. The prescribed procedures were being followed. Vessel work was under the direct supervision of both G-E and CE supervisors, and also separate quality inspectors at all times. Workmen did not appear to be pressured to complete the work within a given time schedule. (hm the basis of these observations and the appearance of the stub tubes prior to cladding, control of the job was considered by this inspector to be adequate. t I -i 4 . a:r ~ ~ ~ K ----:'" " T ' 7 '~ ~ ~

L O 3,. i G. Cladding of the Stub Tubes A substantial and comprehensive joint effort was made by G-E I and CE to develop an automatic weld overlay machine which would perform reliably. The machine as developed utilized a GMAW (gas metal arc weld) process which featured automatic wire feed, a preset rotation speed around the stub tube, automatic indexing from bead to bead, a fixed i angle between the weld wire and stub tube, continuous gas purge, and preset voltage and current inputs. In addition, limit position fingers were provided which changed the direction of rotation to permit cladding the lower portions of the stub tubes which could not be clad by complete rotation around the tube. Qualification of the procedure was completed according to ASME Section IX requirements. Several metallurgical specimens as well as rou-tine bend test samples were prepared to demonstrate weld soundness. All types of specimens were examined by this inspector as well as direct obser-vation of the machine in operation during both qualification runs and in the reactor under production environment. Personnel were given a training program after which they were required to demonstrate their capabilities prior to work in the vessel. The demonstrations were exceptionally stringent in that both G-E and CE engineering personnel had to be satisfied with the individual welder per-formance. These requirements were in addition to those required F the ASME code. Other checks to assure that the applied cladding would be of an acceptable quality included certification checks of the weld wire (all wire used was from a single heat), magnetic checks with a Severn gage, verification of ferrite content (5% -10% limit) by chemical analysis and checking results with the Schaeffler diagram and metallurgi-cal and bend test samples prepared from run-off tabs. These tabs were made by attaching an extension sleeve to a stub tube and continuing the application of clad material onto the sleeve. Four of these run-off tabs, one from each quadrant of the vessel, were prepared. Several of the bend test samples were examined by this inspector and found to be acceptable according to code. In addition, the tops of two of the center stub tubes, which have a greater length than the periphery tubes, were removed for metallographic examination. Samples of these tubes were also directly observed and confirmed to be similar to those shown in Amendment 40, Figura IV-3-A and Figure IV-3-B. In addition to the foregoing checks, dye penetrant examinations were conducted after application of the cladding. If defects were detected, repairs were affected by shallow grinding (minimum thickness of clad was 1/16") or stick electrode metal addition. Approximately 10% of the tubes

9 3 ,. required minor repair. A final dye penetrant test was required which imposed a 1/16" maximum bleedout acceptance criteria. Typical photo-graphs of the cladding operation are shown in Amendment 37, Figures V-1, V-2 and V-3. Figure V-3 is an excellent representation in that the picture was taken with the dye penetrant developer on the tube and illustrates an all " white" condition. Figure V-1 shows the temporary stainless wire which was placed at the bottom of the stub tube at the start of the operation. The purpose of the wire was to furnish a i visual guide to the operator in setting up the machine, so that the stainless cladding would not intersect with the lower Inconel weld metal. During one of the early inspections of the cladding operations, this inspector,was accompanied by Mr.. Collins, Compliance Metallurgical Engineer. Mr. Collins noted a black powder was being deposited on the stub tube surface above the cladding. No effort was made to remove it and as the operation moved up the tube, the powder was absorbed by the weld metal. In Mr. Collins' view, the powder was caused by an inadequate gas purge as the weld bead was applied. During the next visit, it was admitted by the G-E site personnel that one of the gas supply lines was found to be leaking, thus supporting Mr. Collins' view. Investigations of the powder material indicated it to be Fe3 4 G-E personnel considered 0 it not to be detrimental as evidenced by the soundness of the completed work. Another question Mr. Collins raised was the qualification of the procedure on non-sensitized material. As a result of this inquiry, G-E conducted a requalification of the process on sensitized material which demonstrated that weldability was not affected. Bend test samples and metallurgical samples were observed to support this position. Mr. Collins concurred that these results were satisfactory. A third observation made at this time was an apparent brittleness of the stub tube. When the cladding machine was set up on a tube, a collar was first tack welded to the top of the stub tube. After completion of the cladding, the collar was then broken loose and removed. In observing the stub tube in the vicinity of these broken tack welds, the fractured surface looked like a brittle rather than ductile fracture. Subsequent bend tests of actual stub tube material (Amendment 40, Figure IV-1) and microscopic examination of weld samples disclosed the material to be ductile, however. Repair Procedure 6, Amendment 36, describes the use of a mandrel during cladting to control shrinkage. Observations by this inspector con-firmed that mandrels were used. The mandrels were employed to maintain a minimum internal diameter rather than as a means to control residual stresses.

O 3,, H. Inconel Tie-in Welds Following the cladding of the stub tubes, manual Inconel 182 tie-in welds were required at the junction of the Inconel shop weld and the 308L stainless stub tube cladding. Performance of this work was as described by Repair Procedure 6, Amendment 36. From observations of this inspector, more than normal care was taken, as called for in the procedure, to prepare and test the ex-cavated areas prior to deposit of the Inconel weld metal. Since the maxi-mum cracking and subsequent grinding occurred in those areas and because residual stresses sere known to be high, each layer of weld metal was surface ground and dye tested before the next weld bead was placed. This procedure was considered necessary to ensure high quality welds and was followed until the final contour was achieved. Even though this process was slow (five tubes per day), no deviations were made. The final welds were considered to be of high quality by this inspector as evidenced by the smooth contours achieved and the results of intermediate and final dye penetrant tests conducted after the hydrostatic pressure test. (See Amend-ment 47.) I. In-Core Flux Monitor Tube Weld Repairs As previously indicated, these Inconel, field placed welds were found to be faulty in that they contained excessive amounts of slag and porosity. Repair Procedure 4, Amendment 36, was prepared for the repair; however, the procedure as submitted did not include Sketches No. 1 and No. 2. These sketches, showing the limits of grinding and weld build-up, are included as Attachment 2 and Attachment 3 to this report. Of significance in this repair was the need to avoid grinding into the vessel base metal during removal of the defects. The procedure specified dimensional grinding limits beyond which consultation with G-E and CE engineering was required. Several such instances did occur. As a consequence of this experience, templates were subsequently provided and used to define the precise limits of grinding. The weld repairs were conducted using the same techniques as in the Inconel tie-in welds on the stub tubes. Observations of the grinding, in-process welding snd the completed welds were made by this inspector during site visits. The repair is considered to have been performed according to the procedure and the overall quality adequate as demon-strated by successful dye penetrant tests.

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_ Replacement of Field Weld _s_ As with the cladding machine, considerable effort was made by i G-E and CE to provide a fully automatic GMAW (gas metal are weld) welding machine for replacement of the field welds. This device was subsequently developed by rebuilding and modifying the original semi-automatic welder. Because difficulty was experienced during initial welding in the vessel, J a conventional manual, stick electrode procedure was also qualified. Both procedures were ultimately used with approximately 65% of the welds being machine welded. The basic process employed a GTAW (gas tungsten arc weld) root pass, manually applied af ter which the GMAW machine or manual stick SMAW (shielded metal arc weld) method was used for weld buildup. The purpose j of the GTAW pass was to position the CRD housing and to provide a good j root geometry for start of the GMAW welding. Dye tests within the first i 1/3, when the weld was flush with the top of the stub tube, and the completed weld were required. The acceptance standard was a maximum 1/16" i bleedout, the same as that required on all the repairs. In addition to the j dye tests, a UT of each completed weld was required to confirm the quality of the weld. These requirements are spelled out in Repair Procedures 2 and 3, Amendment 36. From observations of the work, and the associated records, the repairs were considered to have been made in accordance with these procedures. Initial attempts to complete a satisfactory weld in the vessel were not successful despite acceptable procedure and welder qualification welds on mock-ups. The first weld was placed in a center tube which was to be cut out to provide metallurgical sampics and is shown in Figure IV-1, Amendment 40. This weld indicated a lack of fusion in the root pass. Sub-sequent changes to the process included making the first weld pass a 360 i 0 traverse rather than an intermittent tack weld; changing the gas purge mixture from 100% argon to a mixture of 75% argon-25% helium; and improving the stability of the power supply. Of the six welds which were removed a second time, five occurred during the time of these improvement efforts. In each case, the decision to replace the weld was made on the basis of UT results, the maximum flaw observed being 1/8" by 1/4" in size. This was considered rejectable and the weld was replaced. As during the cladding operation, mandrels were used on the inside of the CRD bousings to insure a minimum internal dimension. Following placement of the field weld, another manual tie-in weld was necessary on each tube to tie the 308L cladding to the 308L field weld metal. Similar methods were used as in the lower Inconel tie-in welds; principally manual weld metal application, grinding to a smooth contour and dye penetrant testing.

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O G ll~ Observations ' of these operations were made at intervals so as to observe the various stages of the ' operation. Mr. Collins reviewed l s the UT techniques and.the test results and concluded they were acceptable. .In this inspector's view, the work was of a quality equal to or better .than similar work which has been observed in the fabrication shops. j K. Housing Alignment i e With the placement of all new field welds, realignment of the housings was required. Progressive checks were made during welding which. dictated stop-start points to maintain a reasonable alignment. Final alignment, however, was-necessary on almost all'the tubes and was accomplished by adding weld metal at the. junction of the CRD, housing and the field weld on the side of the tube toward which the tube was to be pulled. This work was accomplished according to Repair Procedure 3, Section 4.2, Amendment 40. i IV. Nozzle Safe End Repair A. Identification of Prob 1_em With intergranular corrosive attack observed on the furnace j sensitized 304 stub tubes, all other components made of this material' became suspect. One of the more important areas having safety signifi- . l cance were the 304 stainless transition pieces on'the nozzles, commonly referred to as safe ends. I Early dye tests of the safe ends and the transition welds dis-closed a number of small (< 3/32") spot indications which were considered at that time to be acceptable since they met the code criteria. Documen-l tation of these early results is provided in Amendment 35. As the site personnel became more familiar with the sensitivity of the dye test method and the appearance of intergranular attack indications, additional testing and the removal of metallurgical samples was considered to be j prudent. Although the results were somewhat inconclusive, G-E made the i decision to replace or clad all sensitized.304 material contained in the j safe ends. These included the safe ends on the ten large recirculation i system nozzles, two emergency steam generator nozzles, two core spray J nozzles and one hydraulic return line nozzle. No work was scheduled for 3 the three nozzles in the vessel head. The justification given by G-E was that it would be more economical to perform the work at this time than during operation should a leak later develop. This early work was predicated on the basis that all inter-granular attack was limited to internal surfaces. However, with further-testing intergranular attack was identified on the outer safe end surfaces as well. Subsequently, the work was extended to include the cladding of the external surfaces and also the three nozzles in the vessel head. ,___.,_v. a1

E ~ D 3 +: j,, B. Repair of Safe Ends Results of the investigations and the procedures employed for the repair are documented in Amendments 40 and 43. This inspector observed the progress of the work at varying intervals and concluded that compliance with the procedures was practiced. Included in those items observed were the qualification welds, both procedure and weld:r, and the associated bend test samples. These were satisfactory. Since the cladding work was performed manually, in place, the finished surfaces were not as smooth or polished as those achieved on the. stub tubes. However, all man- [ ual cladding passed the same dye penetrant test criteria, maximum of 1/16" bleed out, thus it is concluded that the work was acceptable. V. Shroud Support Ring i A. Identification of Problem l As with the nozzle safe ends, early dye penetrant tests of this structure were conducted and the results considered by G-E not to be safety significant. The defects, shown by Figure 4, Amendment 35, were removed by grinding. With later discussions and evaluations of the potential problems and confirmation by additional dye and mett11urgical tests, it was concluded by G-E that this structure had also e>perienced intergranular attack and would require repair. These evaluations and findings are documented in Amendments 37 and 40. Because access to the 304 stainless part of this structure was difficult, cladding as a repair method was considered prohibitive. In lieu of cladding, a redundant, auxiliary pin-clevis support structure was de-signed and subsequently installed. Description of these devices, the associated stress analyses, and the installation procedures are spelled out in Amendment 40. B. Observations of Repair Installation of the 36 pin-clevis devices was conducted accord- .ing to procedure and did not entail any unusual considerations. Work access was limited in the shroud area; however, was not prohibitive. All welding was performed manually with stick electrode, j One observation made by this inspector was that the welds were of the filet type rather than full penetration as indicated on Figure VI-2, Amendment 40. G-E responded to the observation by indicating the stress analysis considered the welds as of the filet type. i ..a.- - -- - d

0 3 1 In examining the records, it was also observed that the mill certification reports specified that the yield strength of the pin material was 27,000 psi. Amendment 40 referenced ASIM A-276 as the applicable speci-l fication for the 304 stainless material which states the minimum yield strength must be 30,000 psi. G-E again responded by indicating that the j material used was 304L rather than 304, the 304L having a minimum require-ment of 25,000 psi. Furthermore, the maximum calculated load stresses imposed upon the pin wre below the 27,000 psi test strength. G-E stated ) that Amendment 40 was in error in designating 304 as the material to be used rather than 304L. i Quality of the work was judged to be acceptable by this inspector on the basis of observations of the in process welding and the final dye test results. Test results again met the 1/16" bleedout acceptance criteria. V1. Miscellaneous Aspects of Vessel Repair A. _ Combustion Engineering Participation Active and direct participation by Combustion Engineering personnel in the investigation of the problem and in the repair work was evident through-out most of the repair period. This participation contributed to the assurance achieved by this inspector that the work was properly engineered and properly carried out. High level engineering personnel of proven competence were observed at the site on many occasions. Periodic contact with these in-dividuals at Chattanooga on other pressure vessel work during the course of the Oyster Creek problem, disclosed them to be knowledgeabic of current considerations and in many instances actively engaged in resolving questions independently of the General Electric Company. Crews of supervisory and quality control inspectors from Combustion Engineering were maintained in the pressure vessel during most of the repair. These people were in addition to the General Electric j personnel, thus providing double coverage of the in-place work. CE elected to remove their people following the completion of the cladding and lower Inconel tie-in welding (June). B. Records A comprehensive system of record keeping was established and maintained throughout the program. These are on file by G-E for reference by authorized parties. Several types of data sheets and record forms were i included in the Amendments as samples. To further demonstrate the degree

v o 3 of record control practiced Attachment 4 is attached to this report which shows the amount of detail actually recorded for one specific phase of the repair. The records were examined on a selective and periodic basis to confirm that records were being maintained and that they reflected the work requirements. They were found to be complete and accurate. C. Dye Test criteria Considerable discussion took place during the repair program relating to the sensitivity of tte dye penetrant test method and the interpretation of the observed results. From the Oyster Creek experience, the responsible personnel concluded that the code acceptance criterion was not sufficiently definitive in id'entifying either the spot type inter-granular attack or the weld defect problems actually experienced. For in-stance, the typical " strawberry" type of spot intergranular attack indica-tions were frequently very small and well within code bleedout size limitations. From their experience with extensive dye testing, site personnel formulated their own acceptance standards. These standards enabled the identification of intergranular attack on the outside surfaces of the nozzle safe ends which might otherwise hr.ve been overlooked or considered insignificant by ordinary standards. D. _Use of Mandrels in the published procedures included in the Amendments, there are references to the optional use of mandrels. For record purposes, mandrels were used in the stub tubes (the 79 which had the CRD's removed) during cladding and in the CRD's during placement of all field welds. Noteworthy, hcuever, is that they were used to maintain a minimum internal dimension rather than as a mechanism for reducing fabrication stresses during welding. E. _ Repair of Recirculation Nozzle Arc Strikes During the Compliance quality assurance program review, which was conducted during the same time period as the vessel repair, it was observed that the base metal of the recirculation system nozzles had been damaged by weld arc strikes. Since these are strikes create stress risers which j can lead to cracPing, repairs were necessary. One of the pecularities of the 302B base metal used for the construction of pressure vessels is that it cannot be welded without preheat or post-weld stress relief, thus re-pair by welding under field conditions is generally avoided. The repair actually performed provided for grinding out the defective area and veri-fying by etching that all damaged material had been removed. The procedure for performing this work is included in Amendment 36, Repair Procedure 9.

~ o a l \\ It was verified by this inspector that these repairs were completed according to procedure. Fifteen arc strikes were identified having a maximum depth of 0.007" and ranging in size up to 8" long by 0.035" wide. I VII. Post Repair Hydrostatic Pressure Test l The second hydrostatic pressure test of the reactor vessel at the site was sticcessfully performed on October 5,1968, following the completion of the repair program. The maximum pressure attained was 1,800 psi which is a few percent below the code specified 1507 of vessel design pressure (1,250 psi). G-E stated a higher pressure was not permitted because of a lower design pressure (1,200 psi) of the connected piping. No leaks in the j pressure vessel were detected during any phase of the test. The inspector observed the vessel at pressure and inspected the stub tube region to verify that the repairs were successful from a leak tightness viewpoint. No leaks were observed. The test was conducted according to procedure which had been prepared before performance of the test. The procedure provided detailed check-off 4 sheets for vessel temperature, water chemistry, time-pressure monitoring, as ) well as specific weld joint inspection assignments. These data sheets were properly completed, copies of which were attached to a final report of the test given to the inspector. An unusual occurrence during the test was the detection of chlorides up to 30.9 ppm in the bottom of the vessel during introduction of the TSP (tri-sodium phosphate) solution. TSP was used as a corrosion inhibitor. This degree of chloride concentration was stated to be within the limits of the specified ISP to chloride ratio (5 to 1). The observed concentration was caused by incomplete solution of TSP and mixing in the reactor water during tbs initial introductp, of the TSP. The condition existed for a period r,f about five hours. Cot.xntration of the phosphates ranged up to 5,500 plan during this same time period, well above the specified 5 to 1 ratio. Subsequent to this 5-hour period, the concentration of phosphates stabilized at 450 ppm and the chlorides at approximately 6 ppm. The chlorides originated from the commercial grade TSP which permits a maximum of 0.7% by volume chloride content. Actual test of the material used showed a concentration of 0.0437. chloride. Since the TSP was used as a corrosion inhibitor, G-E did not consider the observed concentrations to be detrimental. 0 Vessel temperature (metal) was maintained at approximately 110 F as measured on the outside surfaces of the vessel and head flanges during the hydrotest period. Water temperatures were approximately 140 F during the same time interval. Filling of the vessel began on October 4 and draining on October 9. Time of the vessel at temperatures above 100 F is estimated 0 at approximately 36 hours. 1

1 0 J _r. Lsg. I i From examination of'the documented test results and the direct-observations made by this -inspector, it is concluded that the-test. a successfully met all objectives. { I -VIII. Post Hydro Inspection Results. ) Inspection consisted of dye penetrant testing all stub tubes surfaces from bottom to top. These surfaces included an approximate i 1" band of the vessel cladding around the' shop weld, the shop weld, the stub tube, the field weld, and approximately 1" of the' CRD housing. In addition, eight stub tubes were ultrasonically tested. Representa-l tive safe end repair locations were also dye tested.- The auxiliary shroud support elevis-pin structures were visually examined. l All test results are documented in Amendment-47. In essence, ] the test results show that the hydrotest resulted in no detectable i changes in the repaired components. Good correlation between pre-hydro and post-hydro test results, both dye penetrant and ultrasonic, i was demonstrated. i In addition to reviewing the test result' records, this inspector observed the dye testing of three stub tubes. The test was conducted l according to prescribed ASME code, Section III procedures and demon-strated an acceptable "all white" no defect condition on the three tubes. From these observations, the results documented in Amendment 47 are 4 considered to be accurate. ) Attachments: 1 Attachments 1, 2, 3, & 4 q _m ~-,a

v 9 9 CHRONOLOGY OF EVENTS 1967 Sept. 29 First field hydrostatic pressure test completed. Water detected leaking from tube Y-31, X-46. Oct. 19-20 First visit to reactor site by this inspector. Vessel observed to be still full of water. Oct. 25-26 First entry into bottom of vessel. Observed dye indication of crack on leaking tube 31-46.. Crack approximately 6" long on high side of tube. J. C. Bertossa, G-E Metallurgical Engineer states G-E will dye test all stub tubes. Oct. 31-Nov. 1 Visited site. Inspector accompanied by consultant J. Chyle. Dye test results of stub tubes (137 total) showed 108 to have indications varying in length from " to 8". Twelve peripheral tubes were probe ground in the cracked areas to 1/8" depth. Grinding failed to eliminate indications but length of crack decreased as grinding progressed into tube. One sample trepanned from tube 51-34 having indication similar to leaker. Sample to be split, half going to Combustion Engineering (CE) in Chattanooga and half to G-E, San Jose, for metallur-gical examination. CE engineers on site to observe dye tests and sample removal. Grinding of all tubes to maximum depth of 7/32" into stub tube wall pro-posed as repair procedure. AEC suggests second sample be removed to confirm findings. Nov. 3 ACRS informed of problem. Nov. 7 Inspector, accompanied by consultant, J. Chyle, visited CE plant in Chattanooga, Tennessee, to observe sectioned sa'ple removed from Oyste; useek m stub tube S1-34. Nov. 8 Information received from reactor site via telephone. Control rod drive (CRD) housing in position 31-46 (leaker) locally hydrostatically pressure tested. Housing leak tight. Leak now believed to be from stainless field weld at top of stub tube joining CRD housing to stub tube. Frobe grinding of weld to depth did not remove porosity. Twenty percent of re-maining field welds also show porosity indications. ATTACHMENT 1

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1 d Lir Grinding 'of stub ' tube surfaces in areas of ' crack' in-dications completed on 45. Most indications are dis-- appearing by. grinding to maximum 7/32" depth. Second~ l sample from position 03-34' removed for metallurgical 'L examination. l ' Site _ personnel state atub tube problem will. delay' fuel ~i loading by two weeks... 9 Nov. 14 I Information from site via. telephone. Indications;ra-- moved.from 70 tubes by grinding. : Six' required grinding. O deeper than 7/32" depth limit. Leaker confirmed to' be in field weld. Dye tests on 60 field welds'show porosity indications on 507.. Two: additional metallur gical samples removed from vessel. G-E, San Jose, con-firms CE metallurgical results on their half of first 'l sample. Grinding on stub tubes and dye. testing of.- field welds continuing. CE engineering personnel con-tinue to observe work. R Nov. 15 G-E-JC-Regulatory meeting in Bethesda to discuss vessel problem and quality control. G-E disclaims. chlorides as contributing cause -- believe cleaning ~ solutions more. likely. G-E taking extensive-investigatory steps.in effort to determine cause. Grinding and contouring of crack areas continuing. Need for stress analysis re-view emphasized by AEC. Fabrication records show stub-tube material to be fully sensitized during final stress relief of vessel. Nov. 16 Dye tests of Niagara Mohawk, Nine Mile Point stub tubes discloses no cracking. Dye tests on two Tarapur, India vessels reported to show similar but more extensive cracking than at Oyster Creek. Nov. 17 Visited. site. Eighty-five of 108 stub tube defects re-moved by grinding. G-E-CE qualifying weld repair-pro-cedure and welders. ' Jersey. Central engages MPR Associates as their consultant. Nov. 21 Inspector and W. Foley, Parameter, Inc., visited CE, Chattanooga to discuss stress analysis considerations. CE and G-E performing independent stress analyses of Oyster Creek vessel design. 'A third party' analysis is also planned.. Results to be available in January. CE fabricating mockup of stub installation for test purposes. Samples confirmed earlier findings. 1 i

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LV Mov. 22 ~ C-E-JC-Regulatory meeting in Bethesdalto further discuss problem and proposed repair. Fabrication-history, cleaning procedures and other background information presented.- Ninety-nine of 108 stub' tube cracks now ground out. AEC requests hold on. representative tubesLfor future reference.' By the time the site is informed, only two tubes remain un-touched. Three of 13 field welds probe ground with. little.or no removal ~of porosity indications. G-E informed by AEC,. repair work could proceed at their. risk. Nov. 28 Site personnel informed-by G-E, San Jose not' to proceed with any weld repair. Nov.'29-Dec. 1 Visited site. Nine metallurgical samples now removed for investigatory efforts. Field continuing to probe grind field welds with generally unfavorable.results. Additional evidence of intergranular' attack on stub-tube walls has been found. CE insisting that welders to be used for repair be requalified to their require-ments. No weld repairs started. Dec. 7 -Amendment 29 documenting problem and investigatory -results received by AEC. Dec. 8 Information from site via telephone. Field welds to be-ultrasonically tested starting today. Six water samples ' collected from low points in reactor system indicated chloride contents from less than 5' ppm up to 131 ppm. Highest chloride found in water from bottom of one of two CRD housings. Dec. 9 Reported status of vessel to ACRS. Dec. 12 CO-DRL meeting to discuss Oyster Creek problem. Engelken suggests licensee be required to submit new safety analysis and inspect all sensitized stainless material in vessel. Dec. 18 Inspector, accompanied by L. Porse, DRL, visited-Chattanooga, Tennessee, to observe stub tube mockup and discuss stress analysis details. Mockup to be used for UT calibration and corrosion tests. Short. stub tube design o;f Oyster Creek vessel indicates J-t- .-._..n n- ~

!.x. ^ 3 - w-o 9 j'.O f {. thermal cyclic stresses will enter plastic zone. Lifetime leakage requirements' questioned. No re-. pairs'will be initiated.at Oyster Creek ~until:. l stress analysis work is completed according to.CE. Dec.;20-21 Visited-site.- Decision made.by G-E tol remove all. field weldsas result of UT. Are currently in '{ process of developing milling machines.- First to be

ready by second week in January.. G-E site construc-i 1

tion manager states repair can be completed in five weeks.' Gene 1,ees, G-E metallurgical. engineer assigned responsibility for vessel repairs'at site. Detailed' 'l mapping-of dye penetrant indications underway. One of { the recirculation loops to be cut for easier access in t to vessel. . i-: f Dec. 29 Information from site via telephone. Recirculation' loop has been cut loose from vessel. i 1968 Jan. 5 Information from site via telephone.. Site to measure ] and forward stub tube ID and OD dimensional profiles .j to ACRS. Work on electric arc milling machine noti l successful. Effort now concentrated on mechanical cutter, currently mocked up at San Jose. Expect to arrive at site mid-January. CE modifying field welding machine to convert it from semi-automatic to fully automatic. Jan. 12' Status reported to ACRS. Jan. 16-17 Visited site. Only minor work in progress on vessel, primarily dye testing. Awaiting tool development. Jan. 26 Visited site. (G-E-JC-Regulatory Quality Control meeting) Comprehensive dye tests show intergranular attack more extensive than originally reported. In-core monitor tube to vessel Inconel welds also found to be defective and { will require repair. First field weld milling machine 7j now at site. Verbal information received that G-E is considering cladding the stub tubes with 308L as permanent fix. ~ ~ -.

7-o a 7,y - i ~ ! ~5- !i Feb. 5 Visited site. Continuing to probe-grind defects in-i in-core monitor welds.. Observed cutting of field welds and obtained chip showing defect._ Four removed. New weld prep surfaces appear to be equivalent to shop quality, i ( l Feb. 6 DRL receives copy of letter, Huggins to Ritter, summa-rizing test findings and proposed repair by cladding. 1 Feb. 9 Status reported to ACRS by Compliance.

l Feb. 16.

Information from site via telephone. Thirty-five field j welds removed by new milling machine.. Selected CRD l housings being removed to achieve work access. Contour-ing of shop welds started by use of special fixture. Three Admiral-Doyle welders sent to Chattanooga to train and qualify stub tube cladding procedure using the I specially developed cladding machine. Feb. 19 Information from site via telephone. Fifty field welds removed. Cutting of field welds also removes 0.8" from top of stub tube and prepares end for reweld. By con-touring lower Inconel shop weld, original length (about 1") of stub tube is maintained.. No weld repair will start until all machining is complete. Inside of one stub. tube with CRD housing removed, dye tested. No indi-cations. No plans to UT inside of stub tubes at'this time. Feb. 20 Inspector and L. Kornblith visited site. Confirmed above information. Total repair expected to be complete by mid-June. Feb. 21 . Briefed representatives of RDT on Oyster Creek problems. Received information about Tarapur in return. Feb. 28 Information from site via telephone. Seventy field welds removed and 11 CRD housings removed. Contouring complete j on five shop welds. Dye tests of stub tubes on insice after housing removal have shown no indications. CRD j housings removed, force working two 9-hour shifts to be sent off site for rework and i cleaning. Work , six i days per week. l 1 ~ .. ~. a ~wm-m b

i +' 4,,. 1, 5, .. - *- = 'j) 1 -6 = Visited site. One hundred four field welds cut and-Mar.z7-8 40 CRD' housings removed.'.. Contouring complete on j seven' tubes. Dye observed on inside of several stub -tubes -- no indications; Cladding machine.at site and being used on mockups to qualify personnel. Observed 3 machine in operation. Also observed the reworked field l weld machine. Obtained sectioned sample from'qualifica'- tion weld.. Sample welds in each quadrant of.the; vessel to be made for test purposes during production welding.1 G-E desires release of the two stub tubes reserved.for - -l g 'the AEC. Access control into vessel tightened up.- ,j Mar. 18 Information from site via telephone. One hundred thirty-five field welds'now removed. Forty-six CRD. housings { out.-- G-E is considering removal of 32 more. Contouring-of, shop welds complete on 20. Welder qualification now complete.- } Mar. 25 Amendment 35 describing latest findings'and proposed repair program received. Regulatory informs G-E that. I repair may proceed at their own risk. j i Mar. 28 Visited' site. Cleanup and final dye testing of stub { tube surfaces in progress preparatory to start of J cladding operation. Further minor surface indications being found on stub tubes.. Sixty-five CRD housings. now out -- 14 others shaved (upper diameter reduced by a few thousandths inches) if removal found desirable. All planned contouring.of' shop welds on high side stub tubes now completed. Total number was 68. Fifty-three-stub tubes with housings removed were checked by UT.. Tests showed nothing..0btained copies of detailed re-pair procedures. 1 t s Mar. 28 4 Amendment-36 containing the repair procedures received. ,j April 3 G-E-JC-Regulatory meeting to discuss Amendment 35. Suit'- ability of shroud support structure questioned in light of corrosion attack. Additional metallurgical samples to-be taken by G-E. April 4 Information from site via telephone. Flushing water used' in vessel checked out at 10 ppb chloride. Seventy-nine housings now out. Cladding of first stub tube expected momentarily.

n E 4.. b if .o -o-9 I ?.'k e ! e . April 4~ Status reported to ACRS.. i F i Briefed DRL consultants (Patriarcha,' Miller) on Oyster April 9 Creek problems and proposed repair procedures. l l April 15 Information from site via telephone. Vessel work de-i layed past week by local labor strike.- ' Strike now over. Seven tubes have been successfully clad. April 17

Inspector. accompanied by W. Collins, 00, Metallurgical ~

j Engineer, visited site. Sixteen tubes clad. Mhadrel being used during welding to minimize dimensional dis-tortion. Interpass temperature being controlled to 6500F. Ferrite checks of as-applied' cladding are checking out at 5-10%. Surface dye checks satisfactory.. Observed black

i soot-like material on stub tubes in process of cladding.

l April 18 Discussed above inspection findings with DRL, DRS personnel.- April 24 Information from site via telephone. Further dye testing and grind probing of in-core monitor tube welds disclose i need for extensive repair. Repair.will be performed after. cladding ~ operation completed. G-E requalifying clad and-l field weld procedures with sensitized material. Are con-sidering cutting off 1" from the top of a clad stub. tube J in center of vessel for metallurgical examination to demonstrate adequacy of repair procedures. April 26 Visited site. Forty-one tubes now clad. Cleaning and final dye test mapping on remainder complete. Two AEC tubes still in original condition. Minor indications on-l stub tube surfaces still being found. Ferrite content of i clad continues to check out greater than 5%. l April 29 Attended Commissioners' Meeting.- Presentation on Oyster-Creek problem given by P. Morris. I 1 May'6 Amendment 37 received. Covers additional information on vessel repair program. G-E states. stress analysis work shows proposed repair is adequate for lifetime of vessel. Inspector, accompanied by R. E. Behmer, Division of Hay 8 Inspection, visited site. ~Eighty-eight tubes now clad. Cladding temporarily halted to permit manual tie-in j welding of stub tube cladding to bottom shop weld. Four tubes partially complete. The manual Inconel welding is I t a l ?

- -~ N A 4' ~ 0. 3 x. ~h.. + 1 ~ requiring more. time than' anticipated.. G-E.now-y -planning removal.'of the tops from two center stub-i ' tubes, one containing a housing welded in by'the re- ~ worked automatic welder. ' Metallurgical samples also-to be removed from sensitized. nozzle safe ends. 'May'9 Briefed DE personnel on results of visit. i May 10 Status reported to ACRS.- i i May 22 .Information f' rom site via telephone. Results of metal-lurgical sample removed from bottom of shroud support l ring shows intergranular attack 30-49 mils deep. One hundred twenty-seven tubes now clad. Inconel tie-in l weld on 14 tubes completed. Center stub. tube samples cut and sent to San Jose for analysis. This included first field weld. May 24 Visited site..One hundred thirty-four of 137 tubes now clad. Tie-in welds complete on 18 tubes. Metallurgical j samples removed from top of shroud support ring and from nozzle safe ends. No results yet. G-E anxious for AEC i to release the two untouched. stub tubes. l May 28 DE, DRS and CO meeting.. L. Porse, Patriarcha, DE con-sultant, and inspector to go to San' Jose to' observe metallurgical samples. Trip to influence decision as to whether or not AEC should release'two untouched stub tubes. June 4 Porse, Patriarcha and inspector visit G-E, San Jose, to '1 examine' metallurgical samples removed from two stub tubes. ) in Oyster' Creek vessel.. Samples also included section of first in place field weld. Samples from Nine Mile Point-vessel also observed ^and showed no. evidence of intergran-ular attack. A decision has been made by.G-E to replace or clad all-304 stainless safe ends at Oyster Creek. Cladding would be limited to the. internal surfaces. De-sign of a redundant auxiliary support structure for the-shroud is currently in progress. June 7 Gave short status presentation to ACRS. June 14 Dr. C. P. Cheng, corrosion consultant engaged by DRL at. 1 recommendation of ACES. Attended DRL meeting to brief Dr. Cheng on history of Oyster Creek problem. Information j from site via telephone indicates work is continuing on manual tie-in welds at bottom of stub tubes. Ninety of I these are complete. i .,7 3 w,

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June 19 Contributed to DRL decision to release two AEC stub tubes for repair.

June 23-24 Visited site. Welding of stub tube to CRD housings (field welds) started with modified procedure. Twelve completed, eight by manual welding following electronic problems with automatic welder. Welds being dye tested at three stages. Completed welds to be UT'd. One hundred fifteen Inconel tie-in welds at bottom of stub tube now complete. Re-dye testing and mapping of in-core monitor tube welds in progress preparatory to repair. June 25 Jersey Central notified by DRL, two AEC stub tubes may be repaired. Some test and measurement conditions recommended. July 5 DRL received telegram from G-E in response to June 25 letter. G-E plans no -sample surveillance program. July 9 Visited site. Collins accompanied inspector. Thirty-six field welds completed using both manual and machine methods. One hundred thirty-five bottom tie-in welds complete. Twenty tie-in welds at top of stub tube be-tween cladding and field weld completed. Setting up grinding machine to remove original field welds on two AEC tubes. One emergency condenser line cut for safe end cladding. Procedure and personnel qualification in progress for cladding work. Contract awarded to Phila-delphia firm to fabricate auxiliary shroud supports -- now a clevis-pin design rather than initial turnbuckle. Witnessed UT of field welds from under reactor vessel using specially designed apparatus. July 12 Gave status report to ACRS. July 23-24 Visited site. Fifty-six field welds complete, 36 by manual welding. Grinding and repair welding of in-core monitor tube welds started -- 22 of 69 completed. Field weld removed from two AEC tubes, outside surfaces clad and bottom tie-in welds complete. Spot checks by dye testing of selected stub tubes af ter completion of all welding have shown no cracking indications. Cladding and/or safe end removal work on nozzles progressing on schedule. No installation of auxiliary shroud supports started. ~ '~

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a 3* : July 25 . Discussed results.of site visit with DRL, DRS and CO.' July 26-Attended DRL meeting with representatives from the Indian government to. discuss Tarapur vessel problems. Problems described as "similar but more extensive" than those at Oyster Creek. August 7 G-E-JC-Regulatory staff meeting to discuss Oyster Creek vessel repairs and results of investigative tests. Cause of cracking still not definitely determined.'Justi-- fication for installation'of auxiliary shroud support T, presented. Visited site, accoinpanied by Dr. Cheng, L. Forse and August 8-V. Stello. Seventy-five field welds now complete, 44 by manual welding. Seventeen CRD housings. replaced as. field welding. progresses in predetermined sequence be-cause of' access considerations. Repair of in-core monitor tubes also in progress, 62 of 69 complete. Housing re-alignment in progress. Dr. Cheng suggested removal of. fiberglass matting placed around completed stub tubes.for mechanical protection. States fiberglass contains chlorides. G-E will comply with suggestion. Nine of ten large recir-culation nozzles now clad. Other nozzle work about 50% l complete. Dye tests show cladding to be satisfactory. J August 9 Presented short status report to ACRS. 4

August 22 Information from site via telephone. In-core monitor i

tube weld repairs completed. One hundred one field-welds complete. UT of welds being perfonned as' they are completed. Results satisfactory to date. Seventy-five-housings.now realigned.. Safe end work about 75% complete. ] Eight of 36 clevis-pin l assemblies welded into vessel as part of redundant shroud support. I August 28 Visited site. One hundred six. field welds complete. s Eighty-five housings aligned. Safe end work about.80%' complete. Twenty-seven'of 36 clevis pin assemblies in-l stalled. Clevis pin welds being dye penetrant tested only. Results OK to date according to Lees. Arc strikes-observed on vessel nozzles in November 1967 have been re-i paired by grinding. Sept. 5 Amendment 40 describing auxiliary shroud support structure plus updated repair program received. i _ _ _ - _ - _ _ _ _ _ _ _ - _ - = ___ _ -. _ _ _ -. ~.

~. Ky a s.- 4 .i i I I ' Sept. 13 Visited site. All housings have been reioscalled' and l .all field and tie-in welds completed.- Twenty tubes re - j main to be realigned.. Dye test and UT of completed i work show the welds meet the acceptance criteria. Safe-7 end work about 90% done. All shroud ~ support work complete. ' Sept. 2C, -Inspector accompanied by Collins visited' site to examine f and discuss UT records of field welds with R. C. Holt.-G-E - ( Test Engineer. Collins reviewed test techniquesL'and re-sults. Work on vessel:in final stages.. Preparations J i, underway to reinstall recirculation pipe removed for i vessel access. G-E will clad outside of safe ends on main recirculation system nozzles and replace safe ends. i on head nozzles after hydro, t Sept. 30- -{ ~ { Oct. 1 Accompanied O'Reilly and Keppler to reactor site'to j discuss quality control aspects other than the pressureL i vessel with JC and G-E. Obtained copy of hydrostatic l pressure test procedure and discussed with G-E personnel.

Reinstallation of recirculation pipe 75%' complete.

Oct. 5-Visited site to observe hydrostatic pressure test. 1 3 Completed as planned with no observed leaks from vessel.. Oct. 17-18 Visited site. Reviewed post hydro dye test results.- Only I 25% of stub tubes dye tested which does not comply with earlier statements. Three tubes were dye tested for in-spector - one not previously checked. All three were " white." No further UT planned.'on field welds. l Oct. 19 Reviewed all literature submitted by licensee relative to 'l the vessel repair to determine test commitments. One. i hundred percent dye tests but no post hydro UT were docu-mented as intended requirements. 3 i -\\ Oct. 21 Attended AEC staff meeting to discuss AEC position relative j to test requirements. G-E to be invited in to discuss. Amendment No. 43 covering additional details of the nozzle safe'end repair. program received. ) Oct. 24 G-E-JC-Regulatory staff meeting to discuss post hydro testing. Dye tests of 47 additional tubes for total of. 79 and UT of 8 were performed between October 18 and this date. No verbal conunitments made by G-E to' perform additional testing.

1 i

i -) 1

4:,. .h .O O - Nov.'1 lACRS updated. Nov.~4 Amendment 47 received documenting post hydro test - .results. One hundred percent dye test of stub tubes -was. performed but no further UT.. Test results _.C-satisfactory. l l =-e.

ff,.' 't, O 3 ?.' TENERAllc) ELECTRIC v e (((([(h ATOMIC POWER EQUtPMENT DEPARTMENT PURCHASE SPECIFICATION g ./ ,.g 8g hyS ki-- CK fff ~hr( O..9 f r1y f/ d ifd//* llmifs fpj-f5 J-/&/ ?? <? 4~! fi:."ap C4d Sn r. ace. = ln fore jh May. l ~~~~ /4 0 (/ S / Y1} ~~~,)' l .N $ ~ Max. V y, + %' l l t ^W. 'Y A,*, y,. H / 'l 9" * (l -/ i / / I / /n/eueclwh l%l 'I / j' l sq,6 - l0. D./>,-(cj @..Me,4 / ~ ~ ~ ~ " l7l / /a j'Z,'0'"'I pio u ai,y l aiNe>-/ny g /l l Y lhcohd Reic' _; e.,,,. Y,Typ. i, V/sid o N e>In1Utn [ X ff/1 Y [ l n & i.. i ';, ~ ' Nofe:; ,. e,..,., j

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/ t Q g,,, 3,z a f q,! \\ fo P.:/e *ae /.1 ~Yd(f g*g."* Ykgp pp .. ^ } Sh -, sp.*dal N, ) l .Pr1CaJttr:n./n 4 j QnW foMs//pe-qbbor. Jkq/lk"(y +9n fo /. pem 7' , f77P/0C Wn fon a 34y cb.4/4 / 3 l v "' f^ / j* ATTACHMENT 2 't. ~i R E w. NO. tsSU E Ds SPEC.NO. V gy, ,i, *'.*s%... t ,.73.gp cons on ensus ou no. ^

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C EN ER AL C) ELECTRIC ATOM!C POWER EQUIPMENT DEPARTMENT PURCHASE SPECIFIC ATION, N 0,ps fe r { r e e k //)-L.or& //pu,.~/ nf. Ele /c/l)he/cf Gf7a k' h /Y} LUM / /7 /.s e nt Co n is. ur y, 7 - + .r,1~ ' ~ ' ' l

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/ f Of ,/ q,y f / ~ \\l/ ~ I i l . /W-s g,,y. p u. . j. 1 '7'" p. i i i ' L.'. s.2 ifa y f I Tyir. 1' i / ./ i / I / ,/ 'j .g.] l i T I .t t ,n - Mits. r'~ :,'r f ' l 1 e /6 ? ^ 's c/: u a I,P.

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~ f 'Y ) N eks ', No / i fOC k 4 5 bk fy/ .WI 0 hOib ~ s s Vai f r-4h 9 / fVCVC s Cf/cThnin9 Wi[l /[ q.. i i i b e per mdicd. v s s \\ s 's i N I ..M} g ATTAC11 MENT 3

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IS SU E D: SPEC.NO. R E W,qo. s epa ,o s / gs {t", e f* * : s y cont ON SMEET Sed NQ. .e ) o

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ST11)PTUNE' WELD REPAlii ~ ~ p 6 ~! i ..+ RECORD P. T.. 7-s y (Referenen:_ Repair Procetlure Numbers 1, 6, 8) ' Stul/ Tub ~c No. 4 Prc Repair D" i Inspector: l Stub Tuho GE p ~ \\ i L270 I l 90 C F' u j Shop Tyelti _ _ D"I" ) 3,. t._.... W t O 90 . )80 2 '.' O O-4 t 180-We):1 Rephir t p i i ,, _.N J ncpector: s GE Stub T.ube t i J270 1 I )0 CE i Shop Wchl. DM c - 2 ........_..._..-mm. ~ 0 90 180 270 0 i .- 4 180 Final o . Jnspector: 7 Stub 'f.ube s GE P.70 < 1 l 90 cg Shop Wel(1 0 90 . 10 270 0 p,3 g ".-.. - ---. y- ~ !B0 WELD REPAIR 1* Proccclure: G E. Dat e: Wclder: N a m e.-- N o. '. G. Ei Supervisor M a.x. Interpann Temp. ........_...._.i ' C. E.. Supervinor i,. Shift Foreman W ci cli ng Cu r r e n t.....

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-. siv.c..... t. ATTACHMENT 4 ),o t N o' -Fo r'ri1 ---- g a-. ..i..m f., -wea***+~**we-'9**********

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o 3 ~ Form OCRPVR 11 MMMY'? STUD TUDE 1.D. HEASUREliEllTS ,',?"" q. Stub Tubo llamber_ Oate 5 Measurements taken by G. E. Inspector 3

• Defore Cladding:

.__0._-100 9q -2700 1/8" Delow Wold Prep. 1" Below Weld. Prep. At Shop \\leid Location 1 After Clodding: O,100 90 -2*/0 0 1/3" Oclow \\/cid Prep. 1" Below ileld Prop. At Shop lleld Location Shrinkage Computed .0 - 180...__ 9 0 -2 / 0 1/C" Delos \\!cid Prep 1" Below t/cid Prep. At Shop \\!cid Location i f.' A z i m d h a's dcier inincd below : VE55ct A g<r5TUC T UBE BElurt MCASUREla e e <>. 270* 0* / / L [(.c NTER) s \\ (V fill CL j O

E 4 s , j f.: Q.'. pgyp,py 3 c '.~ Form OCf;PVR - 12

1. f. '

/. s 57 STUB TUBE' CLADDING 'HACHINE ,e-7. w J7 c SETTlHG UP THE OFFSET SHAFT N10 COLLAR TO'.COMPEt! SATE FOR NOH-CON 0EllTidC s . STUD TODES -I.1 Examine.the upper machined " lip",of the stub tube.- Draw an imaginary diameter !across the stub tube from the point where the lip 1s widest to the point where- -i t is narrowes t. These points can be estimated visually: /

' a;;

e d sTve Tuct uPg ) iMAhmARY Datura ulJE 1 i f ^t n- .L'f

2. Measure the width of. the lip at: the wTdest point.("w") and at the narrowest-

~ d, - point ("n") cnd subtract one from the other to find the eccentricity ("c") of the stub tube. All measurements are taken to the nearest 1/32 inch. ,v f ri

3. Set the offset mandrcl arbor (or housing extension shaf t) In place, with the.

guide.llne of fset to the lof s.of-the Imaginary datum line according to the sketches below. Note how thci offset angle changes with changing emounts of. y v eccentrielty: ovros et-mAnin Asty Lose VATvja oc, 73 w, ,e l j [ 1 ~' c h, ~ e

• l4
  • b c.vont l

l ~ p-g -Q' g.- gr i s1 ' I l 8 'e=h~ c vf5 - e sf cj) e, f i I ((. ~ i ^'

4. Set the cecentric collrir on the offset shaft and rotate it until the saw cut is as far to the rl ht of the imagi ary datum line as the Dulde line (on the 0

l shaft) is to the left: J 'N l0 SAw cut 6UIDC LilJ6 ~ j (CET PRtyloitsLV) s

1. ~~ 1-if tA6f t!Af:y DfiTVIA LINE

5. The shaft and collar are now ready r'the cladding machine to be attcched.

When the mcchine is attached, run it oround the stub tube at least once to

• ~

check whether or not the torch rollcr: tracI: smoothly and evenly all the way around. If not, remove and repeat this entire operation.

/. s ( .F.Jtitil:M 4 _TY1'E 308 AUSTENITIC STAIN 1.NSS STEEL llUFFER PASSES ' l' ' l l.,,'. / h / n 3 o n r 1,/ / / \\ / )' 'n - G T G P l /,l 3 '/ d-r, '/ /s \\ <,-/

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g 3CI.,/ ./ jI \\ k. / / k,/g1kCB' \\\\, ,/ \\ ; / k j( \\ \\\\ ( A/ / [',]j.llK.. \\g 5 '\\ \\g \\ / / l-O / '/ ';/ SI:0P ,\\ \\ \\ \\ g l STE P 4 - ie \\UEtD \\ \\\\x\\ \\ ';f,/i \\\\s \\x i \\ STLP 3 4/;i g '. \\\\\\' i ~ \\, s g z g\\\\; / [

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//,. c e s s \\ j gi \\ '. g \\ . s \\ f s sh\\s\\\\\\\\x s \\ N \\/ / 2\\. s s.< / 4 Step No. 1 - Place a " collar" of heat resistant material over the shop wcld to protect the Inco 182, and place a mandrel inside. Step No. 2 Using either. the GE-3VA, GE-3VB or GE-3VC SMAW process or the GE-4VA GTAW procesn, deposit a wcld bead circumferentially around the entire stub tube 1/2 inch I 1/16 above the junction with Inco 182 shop weld. S h No. 3 Continue with similar circumferential manual deposits to overlay the stub tube wall a minimum of 5/16 inch in the vertical diment; ion. Each 1uccessive pass shall overlap the preceding pasc a minimum of 1/16 inch. Use 1/8" diameter electrode. s for the initial pans. Step No. 4 - Blend to allow good welding visibility for the joining welding j to follow.

,..py -F6rni OCRPVh.1. e.,w aer.s;, w w 3,

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P#- F Wo ld. 5 s .n .C_1115CK_0.1_*F,']NSTJ I a 6 ';.e' ~ Setting Up Cladding-Machine' ~ ' (L ' l J i yc! - Date ...m w .p Operator _ i . i E Stub Tube J ti lld h j{.I. .'[ 6 g y'" 4:j- $ Pled-- . '. l O e to - w w m $$_ <!r l 5 3 1 f

1. - Check physical condition of tractor'(top to bottom):

I" Q Pk$$ j ~ h' N 1) 6 'A ff . 'l (a) Filler wire fed properly between feed rolls gy $$ M g j and out through contact tip properly, with j'~ n o ki n k s o r s n a rl s................................ < (b) Rotation motor engaged with its shaft............... i i .a i -(c) . Vertical travel motor engaged with its gears........ -

.,i

[ (d). Vertical travel limit switches not engaged........... 6 s 5 , '(e).

All loose-spatter removed from cup and a

4 c o n t a c t tip....................................... 't s i ~ (f) Contac t tip not worn or 10o8 c...................... -4 s y '(g) End of contact tip 1/16" inside end of cup........... i i (h) Contact tip in center of cup (left and right) i 4 and 1/16" below center (up and down)............... l 9

5. ;4

'r a g (i) (If short passes are to be run) Connect i l W special control wire between tractor and l '1, .andpendant......................................- s a a : .a 2. Turn on power at machine and pendant and check: ~ <~ f, . 8 ^ (a) Shiciding gas flow is 40 to 50 cEh, and cylinder p r e s s u r e a t l e a s t 50 0 p si........................... I (b) - Wat er pump running at 40 pai..................... 2 .N j (c) No water Icaks in torch, lines, or connections...... 4 i j 4 c l l 1 4

r w..,. g ,y.g ..z g-y>v: gej.e [ 3.. o d.. $,y i + l A., Check-Off List 1 j .c m $y ' # a " Setting Up Cladding Machine u Page 2 gZ [f;; ~ ti. - 2, <e p - 3 J o g_ C 9 w i g- [ .D um k-Tstart button,' and allow tho' tractor tb make. Disengage wire feed rollers, press t &}# -j{ c u - v) 2 l- [ .g ly [ .g$E-exactlyfonc revolution around the stub tube: i g u F td v F (a) One revolution in 60 to 65 s'econde - jj{$'3$'kI { (approximate setting on Rotalion ' ~ - l OIK Sp e e d di a l = 5. 5()........ '......... '................. , pyy ' '(b). Rotation Speed dial locked........'.... ,i c4 j (c) Torch moved upward exactly 9/64" in one revolution (approximate set- { ti n g o n _V e r tic al Sp e ed_ di al = 1. 0 4).................. s (d) Ve rtical Speed dini 1ocked......................... i (c) Re-engage wire feed rollers,_ and tig ht en hand tight................................. r): a 4. Turn Wire Fced switch to " FWD" and measure .the amount of filler wire that emerges from the torch in exactly 15 seconds: (turn torch to side so that wire will nbt run into stub tubc): - .V (a) 99 to 100 inches in 15 seconds (approx-i m a t e d i ni s e ttin g n 5. 3 0).......................... L j p (b) Wire Fe ed control dial locked....... '............... ' s an, s,_ ?h. t_J 4 Y s. j s- , - Aj s,*, ..r + ? :. ? I --..w-- n~ <m, w 4

7:. vy:, . :, 1 _ 1. i,. ,a ~ l - g. 1: s,.. u :c n.~- . w .g :. 3 co \\M : y> ta p c M.k 'S.pv j I O l"' [3 (n ' e,h. b} Ji ci - > $ 4* - Clwck-Off I. int' 3 W 2 {.. rn 3 [d Q lSettiny, Up Claddind Machine .12 age 3

t. m te _

b y bl 4, ' d '1',1 W (O. f.- t-81.0 h*. CV 4 Clip filler wire al proximately 1/4" from j $ N N $ U;' i [,,,hk, ; 5.. contact tip'and adjust torch position as. ' p +C s h ow n b e l ow........................................ __ ., - ',// h ~ .1/. J,/l< .g. s: l. i la L. - # , GQh j' -l' t' / / i s.. STUB i TUB E j 1 v- / 7 b,f l. h':! g / n /gI///n / // 8 W/,/ .,,,pv Q'g(/b p i << t/. ' ~ g To 83 %- 7 IV 75 LESS TI-lMJ ~ i >1-t ,.1. FRONT of cvP . v ,435 (ME ASL/ RED FRotA ~ 4 F ,, SW D! UlJ C L A D - SURI:AclQ u.' E/ - C t> P . e. - p

t c 14.

Tighten clamp to secure torch in place 6, -~ ~ and r e ch e c k cup c1ca r anc e s............................ w., f,.

7.. U welding short beads,. place Mode switch '

qig, in " AUTO INDEX" position. H welding

~ QC complete circular beads, placo.in,"OFF" --[7-b _ L_.s - p o s i t i o n.............................................. _c_ A 4 ,a O ^ -n n ,m: n.w. a ,,s:., .n -+.+s-o,,. ~ .. - - ~. .~

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/- r a gc- . Check-Off I.ist i ' L Setting Up Cladding Machine - Page 4 - h o '$ ( l p

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23 . N o f t, tn /r O 4 hh y' h'odh.'J-p ' l- < 1 8. Position the tractor so that the end of the Q!hf. thy;l[f.by,3j[p' f.,,,4-d"@.;' U,(-V6 filler wire is pointing at the crater left by . p. yf .jg.s+. e d< Tm.A the previous pass, as shown below:- c0 k3 - l' - N ' tractor In.t,is.t.gbc run.irdreve.rs.e.;b. ci d thi's b ' ~ ~,,,..'~r ff.;%g4t,ccoinh.o.; x g.$;,.- r point, then brought.up.1)yity,n-tige;for...; ,d/ ' i e war u < cc J 2 c a ,. direction to remove all back1,h,h'ih}}ie5.1 l-i.f.. .,i3... .t ;5 WpH - ro tation 'gc a r s)............'. '..~. ;>.y. '.g;.&:.6,.j n . ; c..\\...w. :., '.w 1 '. y) 7 . ys..J N, m. + f, W$'N 1 - ~j,', / - ji ? .. 3 4- - f .r. p,3 .Llf *;. '.0 ~ .$hi '.. u. P. ; ' y. r' ^ f G H T C ic LfH E *,. ' Q p &e . {[- M'fqIf '. <l *';;- 4; ) ' ' kg[ ~ ?,

• OF BEADY y

1 . d1 ' Y; ! JE_ [ bmY -(2.f.Tu:._ L.u us:' zWW f> i =.~ u e a,_l..,. ?.2 v A.c e.n::.=: e o _,.~o._.....g.,

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s- -.. -.,, _....,, _... s.. n.y a:-:O:.0 ) a 1-G g. o.- ? r i z,.;_<3. j..".'. a y;,, g.; y,., q,.,ia,, y.g..g.g,4 % % ' ;.,. T; ee ~ o. ., n.. ..A L .:g2.surc.&.;.M GG.2' ~&h:.dL.Md.f.xx::.M%; .l 'T. -[. y t t i e d., ' i-

9.[ - Press the, Wcld Start button.:. ;The arc wil.1(

, [, '. t ? start and the tractor.will begin to move af thr.-, ' t .the prepurge' timers run out.. Quickly check [ v '. li.and, adjust the -following:: ' e (a) Wsid bead overlapping previous bead ' i .[ approximately 1/16". Stop welding and ~ ~ ?- adjust the tractor up or down.with the '1 L J Vertical Feed switch if overlap is ~in- .m ,~ ; correct. ) ( t J i ih .(b) Welding current reading 95 to l'00 amps E. $9.o (stuly tube cold).or 105 to.115 amps:(stub' y tubo hot), and the arc is running with a) ., ', 4,/' steady hissing sound with no"rotigh crack -

• c n

1' g$ ; p ling sounds and producing very littic or no spatter. Adjust Wire Fced sneed until { MQff;j this condition is reachecl,then relock dial.- Make this' adjustment while running. g7 v..

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n J e .,...V s .j g ' lf t-1 + f .- ^ m -n_ aa.A$ ..,.A. m E..u

r. 14 < q J'o1% OCitPVR - D FIGul1E G ' 'J ,4 RECORD OF STtil'. TilnE C1.An WEI,D (l'er Geiier.d Electric ltepair l>rocedure No. 6) Stub Tube Location Date Started PART 1 Automatic Clad Weld (Weld 1*rocedure GE - 10V) ' Wclders: Name No. Checkout performed Name _ _ __N o. per form OCRPVR-13; Name _ No. Yes D No [1 Name No. Gas pressure _ psi, flow cfh. Filler Wire = Amps:begin mi ddic_ cud Sandvik Hi-Sil ER 308 L,. 030 dia. Maximum interpass temperature F Lot No. 7-53735 Ferr(tc present, by Severin Gage Date complete PART 11 Repairs to Clad (Weld Procedure GE-3VA or -4VA) We]ders: Name No. Procedure Name No. Procedure Indicate Repairs Made: - top LIP l 2 70 40 4._.._._-i. O CO 18 0 270 300 8 # Filler Wire: Type Size Lot Shielding Gas: Type Flow cfh Amps DCSP DCRP Maximum Interpass Temperature OF. Ferrite present, by Severin Gage _ . Vipual inspection o. k. O Date completc PART III - Repairs and Tic-in at Interface Be_ tween Stainless Steel and Inconci (Weld Procedure GE-5V) C ; Welders: Name No. Name - No. ' Electrode (Inco E-182 T) Size LotNo. Amps Maximum interpacitemperature _ F. Date Complete SIGN-OFF: Part I complete Part II complete (if required) Part In completc Inspection (s) complete and Inspection Records in Order Generdi Electric Combustion Engineering JDa?.cJBitrm er1 o

.h ,) Form OCRPVR - 15 ?. -s'. ' d' , +

• h*

fl6UR6 7. FINAL til3PECfl0N RECORD - Stub Tube Clad and Tle-in Veld p. Stub Tubc Ho. i Firs.t jnspection-Stalnicss Clad Complete..................O inconel Buildup.and Clad Complete. ........O { r inconel Tic-in to Shop lic1d Con'pletc. ........O j l.0 Surface Excmined By ; Liquid Penetrant O, Other ^ 2.0 Discrepancies Found - ) 2.1 NONE................................ O 2.2 Type Description Quantity or Severity i Spatter or 7xcess metal (Grind off)...... 3 6;f 2 Slag (Remove; Rcweld If necessary)...... 3 Incomplete coverage (Weld up)......... 4 Linear Indica t ions (Grind and Rcweld)......... 5 Porosity Indications (Grind and Rcweld)....... 6 Other 2.3PlotDiscrepancieslindicatetypeandsize): 1 CLAD / / i -- IllCO TIE -IlJ --4 i O' 5'0

• IBO' 2 10*

360' 3 0 Discrepancies Removed: 3.1By9rindIng..............................'.....O 3.2 By welding.....................................O 3.3 By grinding and rewc1 ding *.....................Q

• Form OCRPVR-14 completed.....................O 4.0 Final inspection made (Datc) 1 All Discrepancies Removed / Repaired, Stub Tube Ready for Attachment of CRD Housing.

i 4 G. E.- C. E. , j l e Date r-,,

a. ,- y (,) ., o WN' FHiUltE H AUTOM AT.lC Wi;].D OVERLAY OPTION A e (e._ \\ \\. sc_ / I \\'\\ \\ 'm es/ / t i n o e '%.\\. < GC i ? - } 1/ ( %n: L.. S'. "y// {. -- S TE P l/ J Q sur2 / lI/ i Q-h.., {,,1,y STEP l / \\ h,Il ih !M.. \\g e s # ~' g\\ STEP 4-b b f 'N \\ \\' \\ (, .#y k 5 P \\s \\\\s 1 \\\\i

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d.inco isi \\ \\ \\';*','UJI~.'/ .r -r- : p/ELp \\ '. i \\ \\ \\\\\\ / st:0P /I I + } . / D,i k g \\ \\ '\\\\ '. \\ '\\,* ., $ s i i !l/ -/-) r i \\ i , s g g e /! i .'\\ g i ,e \\ ( s t /l

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o c e i-1 Step 1 - Protective barrier (see paragraph 3. 2. 2. 3) \\ Step 2 - Applied next, by automatic GMAW using type ER308L filler. A minimum deposit thickness of 1/16 inch and a minimum overlap of 1/16 inch is required on each pass. The final as-deposited surface shall be suitably smooth or shall be smoothed 1 r grinding or GTAW s moothing, in order to examine by dye penetr mt to the accuracy established in Repair Procedure Number 1. r Step 3 Remove the mandrel when the overlay has cooled to room tempera-l ture. Artificial cooling shall not be used without APED approval. Step 4 - Using welding procedure GE-5V, fill any ground out arcan in this location, and continue until the surface is flush with the remainder of the cladding and faired in smoothly with the shop wehl. Grind smooth for suhr.equent dye penetrant examination.

J nr. 2. is tp r ~, ,y .l s ' O

.pt 6

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.y' L FIGURE 9 .. - 4/*%f8Mknh,.,,..,Nfdk/M '1 !,~ M ANU ALtWELD'OV$... RLAY OPTIONwk,gN.y '-(Uppfg;'.", h ...3::, s.. . v. ~.o y - 9;,p u,q. 1 =., s a,3;.. n h,hn %..,.. k. n..,! f h..$ h,-l. (^ . [,. . a N. ~ "s ~': W.. .wa., ( . i, + i c; w n 1, b, yW. .;y g y; n; .w g; s.~ c ;..

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4., ' ;, ;- ^ w m-S TE P 3 '.W:V w t; Yl,4:/

k W$ ?G b;i STEP 2 / c., w g.m. m.c. 11 S u,- e.' ,/7.. . ;g p, ;. ~. t y . /.9: ' As

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ef - y;/./] f n '. t ,.I hp g ? 4 s J / p x;: ~ +c e 3/ g STEP.1 , \\ '. /! p

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y STEP 4 S' N \\ 'i ,',g s i - (c ' ,8 g>/ I s s

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-,,j,g/ if . /j lfJC,o - i.g 3 . \\ i y , y _ \\.\\, ' g s/ ,/ SHOP \\,.g,,; *l. / H;b 1, j , 1 ./ wet,D \\ '<w ,s, l s 2 i \\, I I, s \\, i f e / \\. ~ f g\\ \\ ,k '. x \\ \\ \\ \\ r i 4 g s v c. \\s.' \\. 3 1 \\ ]/ i + f s. /> . / s, \\ .< t, \\. .s. /[ .. j / ,s\\3i i i. N,. r\\ \\c l s i Step 1 Protective barricr'(sce paragraph 3. 2. 2. 3) Step 2 Applied next, by manual SMAW, using type E308L filler., A minimum deposit thickness of 1/16 inch is required with a i s br. z ;,.. minimum overlap.of 1/16 inch 6n cach pass. The final as-

r q :- '

deposited surface. shall be suitably smooth' or shall be smoothed by grinding or GTAW smoothing, in order' to examine by dye ,,'s r penetrant to the accuracy established in Repair Procedure No. 1 r E$J,((, ' Step 3 - Remove the mandrol wheti the overlay has cooled to room i ~ ,[,., temperature. Ai tI.ficial cooling. shall'not be used without APED ] s

app roval.

1

• 1.

i { Step 4 Using welding ~ procedure GE-5V, fill any ground.out areas in this { location, and continu.e,.iintil the surface is flush with the remainder s of the.claddirig and faired in smoothly:with the shop weld. Grind smooth for subsequent Elye yienetrant' examination. l*, + r e ^ %.- Y* ;. p- .y_ g-s l, ~ s ? -}}