ML20212H386
| ML20212H386 | |
| Person / Time | |
|---|---|
| Site: | Comanche Peak  |
| Issue date: | 12/18/1986 |
| From: | Beck J TEXAS UTILITIES ELECTRIC CO. (TU ELECTRIC) |
| To: | |
| Shared Package | |
| ML20212H304 | List: |
| References | |
| NUDOCS 8701210383 | |
| Download: ML20212H386 (58) | |
Text
._ . _ . _ ___
l i
COMANCHE PEAK RESPONSE TEAM i
RESULTS REPORT ISAP: V.d
Title:
Plug Welds REVISION 1 O
I C1,dr e f_. a/ o/a I
Issue Co rdinator Data f
, ReVTEC'1le'am Leader
_ A m b' Date a/n/4 a). /Y 11-// r/tt Joh( W. Beck, Chairman CPRT-SRT Date J
- O i
8701210383 870116 i'
- -,- l_ 5- - - - - - - - - . - . - - . - - ~ - - - - . - - - - - - - - - - - - - - - - - - - - - ~ ~ - '
s -
Rsvision: 1 Page l'of 57 RESULTS REPORT ISAP V.d Plug Welds
1.0 DESCRIPTION
OF ISSUE Issue V.d was identified in SSER-10 (Reference 9.1, pages N-329 and N-330) as follows:
"The TRT investigated alleged generic problems regarding uncontrolled repairs to holes existing in pipe supports, cable tray supports and base plates in Units 1 and 2. These holes, which had been misdrilled during fabrication, were repaired by plug welds. Since these supports are Set
- Tic Category I supports and the effects of the welds haa r not been evaluated, this constitutes a violation of Criteria 1X and XVI of Appendix B to 10 CFR 50. Region IV inspections have confirmed the existence of such welds in cable tray supports located in the Unit 2 Cable Spreading Room.
Although tne effects of unauthorized, undocumented and uninspected plug welds in some locations (e.g., the webs of I-beam or in structural members in compression) will be O inconsequential, their effects in critical locatior.s (e.g.,
flanges of I-beams in flexure or in structural members in tension) in critically loaded supports or base plates could affect their structural integrity and intended function."
2.0 ACTION IDENTIFIED The actions to be taken regarding Issue V.d were identified in SSER-10 (Reference 9.1, page N-330) as follows:
"Accordingly, TUEC shall perform one of the following:
(1) Modify its proposed plan to Region IV (TXX-4183 and TXX-4259) to include a sampling inspection of all areas of the plant having plus welds, to include cable tray supports, pipe supports and base plates. Propose alternate methods of inspection where the oblique lighting method is not viable (e.g., locations covered by heavy coats of paint). Perform an assessment of the effacts on quality due to uncontrolled plug welds found during the proposed inspection, as modified above.
Submit a report documenting the results of the inspection and assessment to the NRC for review.
O
_ = _ - _ - - . - . - . _ - . - - - -- _- - -. - _ . . .
Revision: 1 Page 2 of 57 RESULTS REPORT O .
ISAP V.d '
(Cont'd) j 2.0 ACTION IDENTIFIED (Cont'd) f (2) Perform bounding analysis to assess the generic effects of uncontrolled plug welds on the ability of pipe supports, cable tray supports and base plates to serve their intended function. Submit a report documenting ,
the results of the assessment to the NRC for review."
3.0 BACKGROUND
i The issue of uncontrolled plus welds was first raised during the ASLB Hearings (Reference 9.2). At these hearirgs it was alleged '
j' that mielocated holes in cable tray and pipe supports were welded closed without engineering authorization using weld rods withdrawn for other authorized welds and that these plus welds were not I i inspected by Quality Control (QC). The allegers also stated that j
t they were directed by their supervisor to make these unauthorized welds, that they were made without adequate cleaning of the back a side of the veld and thus may have left slag in the welds. It t should be noted that the term " plug weld" as used in this results j report and other documents related to this issue refers to the
' repair of mislocated holes by welding and not a plus weld as defined by the American Welding Society (Reference 9.3),
i In the addendum to the NRC staff testimony at the ASLB Hearings '
(Reference 9.4) Region IV staff reported the results of their i inspection of several areas of-the plant for plus welds. No indications of plug welds were found in the pipe supports examined in the south yard tunnel. However, three horizontal I-beam members i
of cable tray supports in the north cable spreading room were each found to contain indications of two plus welds that were not i i
documented in the construction and inspection records for these
( supports. Subsequent examination of these suspect areas confirmed l
the presence of two undocumented weld repairs in each of these l
thrie support members. The TRT concluded (Reference 9.1, page N-64) that the existence of these welds and the difficulty in detecting them raised a generic concern regarding the potential existence of an unknown number of unauthorized plug weld repairs of questionable quality in base plates, pipe supports and cable tray supports throughout Units 1 and 2.
The repair of mislocated holes in cable tray supports was generically authorized by engineering in Design Change Authorization DCA-5347. No similar generic authorization for repair of mislocated holes in pipe supports was issued by '
O engineering. Instead, the practice at CPSES (Reference 9.5) was to reject pipe supports with mislocated holes rather than repair them.
However, as described during the ASLB Hearings (Reference 9.6), an
__, __ _ _ _ _ _ . . _ _ _ __ _ ~._ . - . .. ._ _ .-
Revision: 1 Page 3 of $7 d
RESULTS REPORT
, ISAP V.d
, (Cont'd) 3.0 BACKCROUND (Cont'd) '
l
\
instance of unauthorized welding on pipe supports did occur. In this instance, the resolution of the unauthorized welding was addressed at the time it occurred. The pipe supports in question I
' were scrapped and the responsible foreman'was demoted to a nonsupervisory position. In addition, for reasons unrelated to repair welding, all pipe supports of the type involved in this case of unauthorized welding were removed from the plant, providing assurance that this specific case did not represent a concern.
1 The construction and inspection procedures applicable to the repair i
velding of mislocated holes at CPSES evolved with time and were >
different for ASME components *(e.g., pipe supports) and AISC components **(e.g., cable tray suoports). For ASME components, ,
base metal repairs required the issuance of a Repair Process Sheet
' (RPS) by the Project Welding Engineer (PWE). An equivalent document (Resolution of Defects form and later the RPS) was used for base metal repairs of AISC components except for the repair of mislocated holes that were welded usins pre-specified techniques (Reference 9.7). In addition, the construction and inspection procedures applicable to cable tray supports did not require documentation specific to the repair of mislocated holes prior to November of 1980. Instead, the inspection of these welds was temporarily documented using a QC acceptance sticker on the support. Thus, while the repair of mislocated holes in cable tray
! supports was authorized, the inspection records prior to November 1980 do not provide a basis to confirm or refute the allegation that some mislocated holes were repaired without OC inspection.
The second ares questioned during the hearing was the adequacy of l- the QC inspections performed. The contention was made that it was difficult to remove the slag from inside the hole prior to welding i the second side without using a pencil grinder. It was alleged '
that pencil grindars were not always available and that QC should have been required to inspect the hole cleanliness prior to welding the second side. However, several velders and foremen from the same work crew as the alleger testified that they never directed, nor were directed by others, to make questionable repairs. Other .
welders also testified that there was no shortage of pancil l grinders.
Components governed by American Society of Mechanical Engineers Codes.
Components governed by American Institute of Steel Construction Codes.
l l-I A _ _ . _ _ _ _ _ _ _
. -- _~. - - _ - -.
d r i
Revision: 1 Page 4 of 57 RESULTS REPORT ISAP V.d (Cont'd) 3.0 BACKCFOUND (Cont'd)
TUGC0 presented test data at the hearing (Reference 9.8) which addressed the issue of slag entrapment in plug welds. The tests showed that, using normal welding techniques, significant amounts of slag could not be entrapped within the veld. Further tests, in ,
which deliberate attempts were made to entrap slag, showed that even with large amounts of slag in the weld, the welded specimens exceeded the tensile strength requirements of the base metal. The
' results of these tests were consistent with the NRC Staff testimony (Reference 9.9) which concluded that if the plug weld were made well enough not to be readily discernable after surface grinding, the weld and the surrounding base metal are at least as strong as the original base metal before it was drilled.
The ASLB, in its opinion concerning welding issues (Reference 9.10) concluded that the allegations related to the repair of mislocated holes were found to be without merit except to the extent indicated ;
in the Board's written opinion, primarily with respect to the !
implementation of repair welding procedures; and even if some weld
, repairs of mislocated holes were not properly inspected and 4 contained defects as alleged, based on the TUGC0 tests and NRC Staff testimony it is unlikely they would have an adverse impact on the safety of the plant.
1 With respect to the documentation of these repair welds, the ASLB concluded that there was a practice of inceterminate extent in which the repair of mislocated holes was not properly documented and that this was a significant violation of Appendix B of 10CFR50.
I With respect to the pipe supports that were welded without proper j
i authorization, the ASLB concluded that most, if not all, of these supports were removed. However, the failure to issue a deficiency document for this violation of welding procedures and to perform an adequate contemporaneous investigation of the extent of the practice was considered to be a violation of Appendix B.
l This report presents the results of the investigations performed in response to the actions identified by the NRC in Section 2.0 and 3
the concern raised by the ASLB related to the practices for documenting the repair welds of mislocated holes. Investigation of the generic ASLB concerns typified by the concern for the adequacy
, of the corrective action for the pipe supports that were welded t
without proper authorization will be addressed by ISAP VII.a.2, "Non-conformance and Corrective Action Systen".
- O L *k
Revision: 1 Page 5 of 57 O RESULTS REPORT ISAP V.d (Cont'd) 4.0 CPRT ACTION PLAN 4.1 Scope and Methodology The objectives of this action plan were to:
Provide additional evidence to confirm the absence or presence of unauthorized or undocumented plug velds in ASME pipe supports and base plates and assess the significance of any plug welds found.
Assess the significance of undocumented plug velds on the quality of cable tray supports.
The plan was based on a combination of sample inspections and engineering evaluations. Sample inspections were used to characterize the number and locations of plug welds to be evaluated. Engineering evaluations were used to assess the
' significance of specific plug welds identified and the limitations of the inspection technique. The sample inspections utilized a combination of paint thickness Os measurements to identify areas of excessive paint thickness requiring removal and oblique lighting to detect suspect veld creas. This technique detected about 84% of the plug welds known to be present.
4.1.1 Pipe Supports and Base Plates 4.1.1.1 ASME pipe supports and base plates required specific engineering authorization to perform plug welds. Accordingly, it was anticipated that neither unauthorized nor undocumented plug welds exist in ASME pipe supports and their base plates. Therefore, the primary purpose of the sample inspection of pipe supports and their base plates was to assess whether unauthorized or undocumented plug welds exist.
Two random samples of ASME pipe supports and their base plates were selected for
, inspection. One sample was drawn from the 1
population representing Unit 1 and Common and the second sample from the population representing Unit 2. The use of separate samples was not based on any expected
(
o Revision: 1 Page 6 of 57 RESULTS REPORT ISAP V.d !
, (Cont'd) 4.0 CPRT ACTION PLAN (Cont'd) difference in the frequency of occurrence of plug velds between the two units, but was l intended simply to increase the inspection '
coverage because of the expected low frequency of occurrence.
The sample plan was based on Appendix D of the CPRT Program Plan using the minimum sample size of 60 with a detection number of zero. However, the confidence level achievable in this case is less than indicated in Appendix D due to the limitations of the inspection technique. To maximize the probability of detecting plug welds, mockup supports with a variety of plug welds were used to refine inspection techniques and select inspectors based on their proficiency in detecting plug welds.
O' In addition, the use of two samples of 60 pipe supports provided additional opportunities to detect plug welds if they were present.
4.1.1.2 When a support was identified as containing a suspected weld repair of a hole, the paint was removed and the suspect area etched to determine if a plug weld was present. If any plug welds were found, they were to be inspected and documented, and these documents were to be compared to the original fabrication and inspection records to determine if they had been authorized and properly documented. While a number of suspect areas were examined in detail, no plug welds were found. Thus, it was not necessary to perform the comparison with the original records or to perform steps 4.1.1.3, 4.1.1.4, and 4.1.1.6 as described below.
4.1.1.3 If the inspection and document review indicates that one or more of the sampled supports or base plates have unauthorized /
undocumented plug welds, an NCR A (Nonconformance Report) will be issued and an U
c - __ _ _ _ . ._ . - -
Revision: 1 Page 7 of 57 RESULTS REPORT
('s%
ISAP V.d (Cont'd) 4.0 CPRT ACTION PLAN (Cont'd) engineering evaluation will be performed to determine. the effect of such welds on the structural integrity of the affected support or base plate.
4.1.1.4 If one or more supports or base plates are found to lack structural integrity due to unauthorized or undocumented plug welds, a decision will be made to either expand the sample, utilize stratified sampling or go to 100% inspection.
4.1.1.5 If no undocumented plug welds are found in the random sample of ASME pipe supports and base plates, it will be concluded that there is reasonable assurance that the structural integrity of ASME pipe supports has not been e
degraded by the presence of unauthorized plug f' welds. If unauthorized or undocumented plug 5
welds are found, but determined, either by inspection or engineering evaluation, not to affect the quality of the supports or base plates, an evaluation of the need for additional inspection will be performed based on the observed trends in the inspection results.
4.1.1.6 All supports found with unauthorized /
undocumented plug welds will be identified via an NCR and modifications will be implemented if required.
4.1.1.7 As part of this investigation, the existing QC inspection and documentation procedures were reviewed and the results are discussed in Section 5.0.
4.1.1.8 The third-party conducted the reinspection and provided an overview of the full scope of the effort.
O
0 Revision:
1 Page 8 of 57 RESULTS REPORT ISAP V.d
, (Cont'd) 4.0 CPRT ACTION PLAN (Cont'd) 4.1.2 Cable Tray Supports It was recognized that cable tray supports do exist for which the documentat?.on specific to the inspection of individual plug welds is not available. Therefore, the
- primary purpose of the sample inspection of cable tray supports was to determine the number and location of such welds in order to determine the effects on the quality of the supports'.
Random samples of cable tray supports in both Units 1 and 2 were selected for inspection. The steps involved in this investigation parallel those for the pipe supports and base plates as described in Sections 4.1.1.2 and 4.1.1.4 through 4.1.1.6.
4.1.3 Engineering Authorization of Cable Tray Support Plug Welds The third-party reviewed Design Change Authorizacion DCA-5347 which generically approved plug welding in cable tray supports to ascertain whether a sufficient teci:nical justification existed at the time of issuance. That technical detail could include structural calculations, tests, or justification based on applicable industry codes and standards which are part of the licensing basis.
4.1.4 Documentation of QC Weld Inspections l
The history of programmatic requirements and implementing procedures fer QC documentation, as applicable to plug welds, was reviewed by the third-party. This review was undertaken with the knowledge that, prior to November 10, 1980, weld-specific documentation was not required by procedure. The review assessed compliance with the QA program and licensing commitments as documented in the FSAR.
4.1.5 Evaluation of Root Cause and Applicability to Other Areas The action plan also contained provisions for the O evaluation of root cause and generic implications in accordance with Appendix E of the CPRT Program Plan.
e _ _ _ _ _ _ _ _ _ _ - - _ - - - - _ - - - -
a Pavision: 1 Page 9 of 57 RESULTS REPORT ISAP V.d (Cont'd) 4.0 CPRT ACTION PLAN (Cont'd) 4.2 Participants Roles and Fesponsibilities The organizations that participated in this effort are listed below with their respective scopes of work.
t 4.2.1 CPSES Project 4.2.1.1 Scope Define population and select sample Prepare mockup supports and assist i in the development of the inspection procedure Assist in the review of the history of procedures / program requirements
() for inspection and documentation of plug welds Assist in the evaluation of inspection resul a Provide the basis for the generic authorization to repair mislocated holes 4.2.1.2 Personnel Mr. C. Moehlman Project Mechanical Engineer Mr. W. Baker Senior Project Welding
(
l Engineer Mr. W. Wright Project Welding Engineer 4.2.2 Third-Party Activities 4.2.2.1 Scope Review population definition and sample selection
Revision: 1 Page 10 of 57 RESULTS REPORT ISAP V.d (Cont'd) '
2 4.0 CPRT ACTION PLAN (Cont'd)
Inspect pipe and cable tray supports QA/QC Review Team (ERC)
Evaluate QC inspection methods and documentation requirements Review TUGC0 engineering evaluations Recommend procedure changes if applicable Prepare Results Report 4.2.2.2 Personnel Mr. H. A. Levin TERA Corporation - CPRT Mechanical Review Team Leader Mr. J. C. Miller TERA Corporation - CPRT i
TRT IssLas Manager 1
Dr. J. R. Honekamp TERA Corporation - CPRT TRT Technical Manager Mr. C. Spinks QA/QC Review Team (ERC)
Inspection Supervisor Dr. F. A. Webster Jack Benjamin &
Associates (JbA), - CPRT Statistics Advisor Mr. R. L. Shipp TERA Corporation - Senior Materials and Welding Engineer Mr. R. Sanan TERA Corporation - Issue Coordinator Dr. C. D. Lundin Material and Welding Consultant 1
. e - . .- . ._ - -
s Revision: 1 Page 11 of 57 RESULTS REPORT ISAP V.d (Cont'd) 4.0 CPRT ACTION PLAN (Cont'd) 4.3 Qualification of Personnel -
The QA/QC Review Team inspectors were certified to the requirements of the ERC Quality Assurance Program and met the requirements of ANSI N45.2.6, " Qualification of Inspection, Examination, and Testing Personnel at Nuclear Power Plants".
The inspectors were also trained in the requirements of the QA/0C Review Team plug weld inspection procedure (Reference 9.11) and tested using the mockup supports to determine their proficiency in detecting plug welds.
Third-party participants in the implementation of this Action Plan met the personnel qualification and objectivity requirements of the CPRT Program Plan and its implementing procedures.
Other participants were qualified to the requirements of the
- CPSES Q'2ality Assurance P.rogram or to the specific require:ents of the CPRT Program Plan. Activities perfctmed by other than third-party personnel were governed by the applicable principles of Section III.K, " Assurance.of CPRT -
Program Quality", of the CPRT Program Plan.
4.4 Procedures 4.4.1 A procedure (Reference 9.11) was developed for the inspection of cable tray supports, pipe supports and their asscciated base plates to identify misdrilled l
holes that have been welded. This procedure contained ~
criteria for limits on paint thickness and methods for paint measurement. These criteria were developed based upon a test program that established limits on paint thickness at which plug welds can be detected via visual inspection. Inspectors were specifically trained and qualified for this task. -
4.4.2 Inspection of all identified plug welds was performed utilizing the criteria for visual inspection as delineated in AWS D1.1.
i O
I A
Revision: 1 Page 12 of 57 1
RESULTS REPORT ISAP V.d
. (Cont'd) 4.0 CPRT ACTION PLAN (Cent'd) 4.5 Decision Criteria / Acceptance Criteria The decision criteria and acceptance criteria for pipe supports and base plates are described in Sections 4.1.1.3 through 4.1.1.6. The decision criteria and acceptance criteria for cable tray supports are outlined in Sections 4.1.2 and 4.1.3.
5.0 IMPLEMENTATION OF ACTION PLAN AND DISCUSSION OF RESULTS This section describes the results of third-party investigat' ions and reviews related to: inspections of pipe and cable tray supports and their associated base plates and reviews of construction and inspection records (Section 5.1); review of the engineering basis for generic authorization of plug welds in cable tray supports (Section 5.2); reviews of plug weld inspection and documentation requirements (Section 5.3); bounding evaluation of O
- the effects of plug welding on the structural integrity of the components involved (Section 5.4); safety significance of identified construction deviations (Section 5.5); a statement about generic implications (Section 5.6); and out-of-scope findings identified during the above investigations (Section 5.7).
5.1 Inspection of the Sample of Pipe and Cable Tray Supports and Comparison with Construction and Inspection Records The initial step in determining the presence of unauthorized or undocumented plug welds was to establish an inspection pro,cedure that would detect plug welds and to train the inspectors in using the procedure. The second step in the investigation was to identify the populations of potentially affected pipe and cable tray supports and to obtain representative samples of the populations. These samples were then inspected. The final step was to compare the results of the inspections with existing project documentation to determine whether or not unauthorized or undocumented plug welds exist.
5.1.1 Development of Inspection Technique and Inspection Procedure There are two basic methods for locating a weld in a carbon steel member. These are:
O
Revision: 1 Page 13 of 57
(}
\/
RESULTS REPORT ISAP V.d (Cont'd) 5.0 IMPLEMENTATION OF ACTION PLAN AND DISCUSSION OF RESULTS (Cont'd)
Visual inspection, which relies on chanFes in the surface contour or roughness between the weld metal and the base metal as the basis for detection, and Remeval of paint and/cr cleaning of the surface to be examined followed by etching of the surface with a nitric acid solution, which produces a discoloration of the heat-affected zone.
To provide a basis for evaluating the effectiveness of the visual inspection technique and the proficiency of individual inspectors in detecting plug welds, sixteen (16) mockup supports containing fifty-three (53) plug welds were fabricated. These mockup supports were duplicates of supports used in the plant. Most of the plug welds in the mockups were located in areas where a
\-
bolted connection was intended by the design. However, come were arbitrarily located in areas where bolted connections were possible, but none was intended by the design. The plug welds were made and ground, using the same techniques as are used in the field, and the supports were painted to maximum thickness permitted by the specification. The mockup supports were then installed on the floor and ceiling of the welding shop to simulate field cenditions.
Based on examination of the mockup supports by Project and third-party personnel, it was apparent that plug welds located in base metal that had a textured surface (i.e., slight roughness) were easily detected through the maximum paint thickness because of the difference in texture between the ground surface of the veld and the unground base metal. For plug welds located in base metal that had no visible surface texture, detection depended on changes in the surface contour in the welded region. Low-angle reflected light was found to be an effective method to detect these irregularities on a smooth surface.
a _
Revision: 1 Page 14 of 57 RESULTS REPORT ISAP V.d
, (Cont'd) 5.0 IMPLEMENTATION OF ACTION PLAN AND DISCUSSION OF RESULTS (Cont'd)
The inspection technique selected utilized a combination of the visual examination and acid etch methods together with paint thickness measurements.
For each support in the sample the paint thickness was measured to deterniine if it was greater than 0.015 inches which was the paint thickness used for mockup inspections. The inspection procedure required the paint to be removed prior to visual examination in all areas where it was thicker than 0.015 inches. Each support was visuelly examined for indications of plug selds. All suspect areas were marked and the surface cleaned and etched to determine if a plug w6ld was present.
Af ter development of 'the inspection technique, inspectors were trained and tested using the mockups.
The initial training and testing involved ten candidate inspectors. In the inspection of the mockups, each inspector worked indepsndently and was not told before or after his inspections how many plug welds were present in the mockup supports, where they were located, or which plug welds were missed in their inspections. 'These inspections (Reference 9.12) produced an average detection rate of 76.7%. Three plug welds (5.7%) were not detected by any of the ten
~
inspectors. Of the ten candidates, four were selected for the in-plant inspections. The average detection rate of plug welds in the mockups for this group of four individual inspectors was 82%.
l Initial inspections of pipe and cable tray supports in
{ the plant were performed individually by the four j inspectors. The results of these inspections showed
- that the inspectors had detected only 42% of the plug a
welds documented in the original inspection records for l the sample of 120 cable tray supports.
In order to improve the detection rate, all the pipe and cable tray supports in the sample were reinspected
' using two inspection teams, each consisting of two inspectors. In this approach the first inspector examined the support, documented his findings and provided them to the second (the checker) inspect ar.
The checker then reinspected the support for suditional i
e #
, - . - ~ - - - - -O,.,-. ..
m . . . . _ , - _ , , , - - - , - - ,- _,,.,,- _ , , n- . . - . - , _ _ - - . . - - -
i Revision: 1 Page 15 of 57
/"'h RESULTS REPORT V
ISAP V.d (Cont'd) 5.0 IMPLEMENTATION OF ACTION PLAN AND DISCUSSION OF RESULTS (Cont'd) suspect areas. The average detection rate for the two teams, based on their performance on the mockup inspections, was 87.5%. More importantly, these inspection teams detected 83.9% of the documented plug welds in cable tray supports in the plant.
5.1.2 Population Determination and Sample Selection The populations of pipe and cable tray supports were established as described in Reference 9.13. The Hanger Information Tracking System (HITS) was used as the source document for the population of pipe supports.
The accuracy of the HITS data base has been verified by the OA/QC Review Team, a third-party organization (Reference 9.14).
The population of cable tray supports was based on the list of Field Sketch Electrical for Cable Tray Hangers I)
\-
(FSE-159) drawings in the Document Control Center. A list of cable tray supports obtained from the Unit 2 Package Flow Group was used to separate the Unit 2 supports from the total list. (The Unit 2 Package Flow Group is the site organization that assembles and ccatrols the Construction Work Packages). The accuracy of the resulting Unit 1 population was verified by checking it against a list of Unit 1 supports compiled by Engineering from a review of " map" drawings, Electrical Drawings that are marked to identify hanger locations, types, and hanger numbers. The accuracy of the Unit 2 population was verified by comparison with 200 supports arbitrarily selected in the plant. All the supports selected in the plant were on the list.
The populations of pipe and cable tray supports were sampled randomly in accordance with the guidelines in Appendix D of the CPRT Program Plan to obtain a sample of 60 supports from each of the four populations of supports and their associated base plates. The random selection process was checked by the third-party (Reference 9.15 and 9.16).
The initial sampling of pipe supports included Class 5 (non-ASME) supporta on the basis that they were welded using the same procedures that were used for ASME
\ supports. Fifty-one (51) Class 5 supports were
- E
- .=
( . . . - - .. .- - . . . - . - .
Revision: 1 Page 16 of 57 RESULTS REPORT ISAP V.d (Cont'd) 5.0 IMPLEMENTATION OF ACTION PLAN AND DISCUSSION OF RESULTS (Cont'd) l obtained by the random sampling process and inspected.
' However, since the concerns rais:d in the ASLB hearing relative to pipe supports were focused on ASME supports, additional ASME pipe supports were drawn at random to obtain two samples of 60 ASME pipe supports for inspection (one sample from Unit I and one frem Unit 2).
An error was detected during a third-party audit of the random sample selection. The impact of this error was evaluated by the third-party and the statistical '
consultant and was found to have no effect on the final inspection results (Reference 9.16), even though it affected the randomness of 14 out of the 250 samples.
L 5.1.3 Results of Pipe Support Inspections
'. A total of 130 ASME and 51 non-ASME pipe supports and '
their associated base plates was initially examined using single inspectors. Eight (8) supports were identified as having suspect areas (i.e., areas with indications of surface imperfections that might indicate a repair). Each suspect area was stripped of paint and etched. No plug welds were present in any of
' the suspect areas. The same sample of 130 ASME pipe supports and base plates was reinspected using two-inspector teams as described in Section 5.1.1. One (1) additional suspect area was identified during this reinspection. Again, when the paint was removed and the suspect area _ etched, no plug welds were found. The records for both inspecticus are contained in Reference i
9.17.
As a check on the effectivt s of the reinspection, the document packages for t 130 ASME supports in the sample were reviewed by the trd-party to determine if any plug welds were authori ,
This review (Reference l 9.18) confirmed that no plu ids were authorized. '
i Since no plug welds were found in either inspection, I
the record reviews indicate that no plug welds were authorized, and the pipe supports involved in the ,
incident of unauthorized welding were. removed from the '
plant, it was concluded that there is reasonable O assurance that the ASME pipe supports and base plates in the plant do not contain plug welds.
l l
Revision: 1 Page 17 of "'/
RESULTS REPORT ISAP V.d
, (Cont'd) 5.0 IMPLEMENTATION OF ACTION PL/.N AND DISCUSSION OF RESULTS (Cont'd) 5.1.4 Pesults of Cable Tray Support Inspection's Table i summarizes the results of the inspections and document reviews for the 120 cable tray supports in the sample. More specific information on the 26 cable tray supports in which plug welds were found is provided in Table 2. As discussed in Section 5.1.1 all 120 cable tray supports were examined by individual QA/QC Review Team inspectors and then reinspected by the two inspection teams. The information provided in Tables 1 and 2 are the combined results of both inspections.
A total of 57 plug vulds was found, all of which passed the visual examination criteria of AWS D1.1.
Forty-seven (47) of these plug welds (82.5%) were documented in the original inspection records for the supports. The Project has issued NCRs (Nos.
M-86-104369X through M-86-104374X) for the six (6)
O (d supports which contained the ten (10) undocumented plug welds. For these six supports the QA/QC Review Team inspectors found the welds to be satisfactory.
However, since the inspections performed under this action plan were based on a random sample, the results imply that additional undocumented plug welds exist.
This was documented in a DIR, as discussed in 5.3.2.
The fraction of supports containing ore or more undocumented plug wolds can be estimated from the inspection results. From Table 1 it can be seen that 6 of the 120 supports inspected, or 5%, contained one or more undocumented plug weld. If this observation is adjusted for the fraction of plug welds that were inaccessible and the fraction of plug wald not detected by the inspectors, the estimate of the number of supports with one or more undocumented plug weld becomes 6.9%.
The results of the inspections and document reviews were also examined for trends related to the occurrence of undocumented plug welds. Two trends were observed.
First, no undocumented plug welds were found on supports that were initially accepted by QC after Dec0mber 1979 (see Table 2). As discussed in Section p 5.3, the December 1979 date correlates with a change in Q the method of documenting the inspection of plug welds.
The second trend that can be seen in Table 2 is that all the undocumented plug welds were found on supports
- a __ _ _ . _ _ __ __ -.- - . - - - - - - ---
/
Revision: 1 Page 18 of 57 RESULTS REPORT ISAP V.d ,
, (Cont'd) l 5.0 IMPLEMENTATION OF ACTION PLAN AND DISCUSSION OF RESULTS (Cont'd) in Unit I and Common. However, it is known from the inspections performed by NRC Region IV (Reference 9.4) that some undocumented plug welds are present in cable tray supports in the Unit 2 cable spreading room.
Review of the installation records for the three cable tray supports with plug welds identified by NRC Region IV indicates that these supports were installed in December of 1979 although they were not accepted by QC until April to July 1980. Thus, it was concluded that the correlation with the date of installation is the underlying trend and that the observation of no undocumented plug welds in the sample from Unit 2 is the result of the fact that most Unit 2 cable tray supports were installed at a lat r date than those in Unit I and Common.
It should be noted that correlation with the date of
,s installation does not imply that all plug welds in supports initially accepted by QC prior to December 1979 are undocumented since some of these plug welds could have been made'after the method of documenting plug weld inspections was changed. This is supported by the information in Table 2 which indicates that of the fourteen (14) supports with plug welds that were initially accepted prior to December 1979, eight (8) supports or 57% centained documented plug welds.
5.2 Review of the Engineering Authorization for Plug Welding 5.2.1 Cable Tray Supports The third-party reviewed the technical justification for DCA-5347, which provided the generic authorization to repair mislocated holes in cable tray supports. The purpose of this DCA was to specify which holes in the cable tray supports must be welded in terms of the hole size and hole spacing. The welding process and the inspection ard documentation requirements for these i
welds were defined by the specifications and procedures that control the fabrication, installation and inspection of cable tray supports. As discussed in the ASLB testimony and the TRT review (Reference 9.1 page N-62) and (Reference 9.9), the weld procedure specified meets the requirements of the AWS D1.1 code and, if Os properly implemented, results in a weld that is stronger than the base metal.
i 1
,,---------n - - - - - - , - - ~ - - ~
Revision: 1 Page 19 of 57 RESULTS REPORT ISAP V.d (Cont'd) 5.0 IMPLEMENTATION OF ACTION PLAN AND DISCUSSION OF RESULTS (Cont'd)
Review of DCA-5347 (Reference 9.19) revealed two discrepancies: criteria specifying which holes could be left unwelded were not clearly stated and justification for allowing holes up to 3/4" in diameter to remain unwelded was not adequate. These discrepancies were documented in DIR-D-0018 and classified as a deviation. As part of this effoet.
Ebasco provided a reanalysis addressing.DCA-5347. This reanalysis was conducted to establish justification supporting the criteria specified in the DCA.
The DCA criteria have been incorporated into the Ebasco cable tray support as-built inspection program, and the effect of the presence of unused holes up to 3/4" diameter continues to be considered in the Ebasco cable tray requalification program.
Implementation of these programs is being overviewed by ,
the third-party under DSAP VIII, " Civil / Structural".
5.2.2 Other Components Welding of mislocated holes was authorized in other components designed and fabricated to the AISC/AWS codes (non-ASME). The specific component types and the documents which authorized the repair-of mislocated l
holes are listed in Table 3.
The base metal welded in the components identified in Table 3 was principally A-36 steel and carbon steel sheet, e.g., A569. The repair welds were made primarily using two welding procedures (WPS-10046 and (WPS-10082) and appropriate filler mettis (E7018 and E70S-2). For these repairs, the combination of the matching filler metal and welding technique yields a welded region that is stronger than the base metal.
l The fabrication and inspection of these components l were, in many cases, controlled by differeat procedures k l from those used for cable tray supports (see Table 3).
l However, as for cable tray supports, a qualified weld procedure specification was used and visual weld inspections were performed in accordance with AWS D1.1.
The third-party has reviewed the construction and
Revision: I Page 20 of 57 RESULTS REPORT
, ISAP V.d (Cont'd) 5.0 IMPLEMENTATION OF ACTION PLAN AND DISCUSSION OF RESULTS (Cont'd) inspection procedures for these components and a sample of their inspection records and found them to be comparable to the procedures and inspection records used for the repair of mislocated holes in cable tray supports (see Section 5.3.3).
~ ,
5.3 Review of Plug We1d Inspection and Documentation Requirements The third-party has reviewed historical and current procedures for the inspection and documentation requirements associated with the repair of mislocated holes. The purpose of this review was to assess the adequacy of the procedures regarding weld repairs of mislocated holes and to determine their compliance with the QA program and licensing commitments. The results of this review are described in the following sections.
5.3.1 ASME Pipe Supports The current procedure that controls the fabrication of ASME pipe supports and their base plates is CP-CPM-9.10 (Revision 15). (A list of procedure titles is given in Table 4.) This procedure requires that welding be performed in accordance with weld procedures qualified per the requirements of ASME Boiler and Pressure Vessel Code Sections III and IX and that the welders be qualified for the weld procedures used. The procedure further requires the preparation of a Repair Process Sheet (RPS) for the weld repair of base metal defects (mislocated holes), and references procedure ,
CP-CPM-6.9G for veld documentation requirements.
CP-CPM-6.9G provides inscructions for the preparation and approval of the RPS and requires that the RPS include the inspection requirements and any necessary.
QC hold points for the repair weld.
Procedure CP-CPM-9.10 was first issued in September 1980. Prior to that time the fabrication of ASME pipe supports was included in CP-CPM-6.9 and its associated appandices. These earlier procedures also required the use of the RPS to authorize and document the weld repair of base metal defects. Based on this review, it was concluded that the requirements for inspection and .
documentation of such repairs in ASME pipe supports and O their base plates are adequate and have complied with QA program and licensing commitments.
_ _ _ , _ _ , - . _ _ . . , ~ , - - - - . - - - - - - - - - - - - - - - - - - - - - - - - - - ' - - - ~ - - ~ ' ' " ' - - ' ' ~ ^ ' ' ' ' -"' ' '
g Revision: 1 Page 21 of 57 RESULTS REPORT ISAP V.d (Cont'd) 5.0 IMPLEMENTATION OF ACTION PLAN AND DISCUSSION OF RESULTS (Cont'd) 5.3.2 Cable Tray Supports
, The current procedures that control the fabrication and -
installation of cable tray supports are ECP-10 _ .
(Revision 8) for Unit I and ECP-10A (Revision 4) and ECP-10B (Revision 1) for Unit 2 and other areas not included in ECP-10. The corresponding inspection procedures are QI-QP-11.10-2 (Revision 29) and -
QI-QP-11.10-2A (Revision 9). The procedures for fabrication and installation require that all welding and related inspection be performed in accordance with AWS Dl.1 and B&R welding specification WES-029. The welding process specified for general welding, which includes plug welds, is specified in WPS-10046.
The inspection procedures require a visual examinaticn of all welds in accordance with procedure QI-QP-ll.21-1
' which includes the AWS Dl.1 acceptance criteria. Both the inspection procedures and QI-QP-ll.21-1 refer to procedure QI-QP-16.0-5 for the repair of mislocated holes. Procedure QI-QP-lL '-5 is a general procedure
- l. for reporting base metal defects in non-ASME items.
Section 3.1 of this procedure contains the following requirements for the velding of mislocated holes in cable tray supports:
Document the hole as unsatisfactory on an inspection report.
Prior to welding obtain engineering approval via an engineering design document or by engineering approval on an RPS.
For repair of holes in egble tray supports or conduit supports that are accessible from both sides, a construction operation traveler can be used to document the repair in lieu of ,
an RPS.
Document the results of the visual weld inspection and the RPS, design document, or traveler number on the inspection report.
These requirements and other information provided in O this procedure related to the repair of mislocated holes are consistent with the more detailed requirements provided in WES-029 for the repair of base metal defects in non-ASME components.
- L . --- . - - . . . - - - . --- . --- - - - - - - - - - - - - - - - - - - - - - - - - - ---
0 Revision: 1 Page 22 of 57 RESULTS REPORT ISAP V.d (Cont'd) 5.0 IMPLEMENTATION OF ACTION PLAN AND DISCUSSION OF RESULTS (Cont'd)
In addition to the above procedures that control the normal construction and inspection activities for cable tray supports, the cable tray support requalification l program also addresses mislocated holes as part of the as-built inspections. These inspections are controlled by QI-QP-11.10-9 and QI-QP-11.10-2A, which primarily address the support configuration. However, they do contain the acceptance criteria for unused holes and instructions for the documentatian of holes that do not meet the acceptance criteria and the inspection of their repair. These inspection and documentation requirements are the same as described above for mislocated holes encountered in the normal construction
! and inspection process.
The evolution of the inspection and documentation requirements for plug welds in cable tray supports is
- i. summarized in Table 5. As indicated in Table 5, the applicable procedures and specifications did not provide explicit instructions for the inspection and documentation of plug welds prior to November 1980.
However, the Brown _& Root welding specification (S-52.01-106B) and the applicable inspection procedures (QI-QP-11.3-2 and QI-QP-11.10-2) clearly require all welds to be inspected in accordance with AWS D1.1. In addition, these inspection procedures provided for the use of an inspection report, a constructior. operation traveler or, in the earlier versions, an Electrical Hanger Inspection Checklist to document the results of weld inspections. Further, the Resolution of Defects (ROD) and later the RPS was provided to authorize and document the weld repair of base metal defects (unused holes). Both the ROD and the RPS included the instructions for making and inspecting the repair weld and documenting the results of the inspection.
Since the procedures in effect prior to November 1980 provided several methods to document weld inspection on cable tray supports, interviews were conducted with Welding Engineering and inspection personnel who were involved in the repair of mislocated holes in cable ,
tray supports at that time. The interviews with Welding Engineering personnel (Reference 9.20)
() indicated that there was a question at the time as to whether mislocated holes must be considered base metal defects requiring the preparation of an ROD /RPS. The h ___ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ - - _ _ _ - - _ _ _ - _ . _ - _ . - - - - - - - - - - - - - - -
Revision: 1 Page 23 of 57 RESULTS REPORT O ISAP V.d (Cont'd) 5.0 IMPLEMENTATION OF ACTION PLAN AND DISCUSSION OF RESULTS (Cont'd) interpretation provided by Welding Engineering was that since the repair of mislocated holes in cable tray supports had been authorized by DCA-5347, and the weld was an AWS D1.1 pre-qualified joint configuration, an ROD /RPS was not required. An ROD /RPS would be required for those cases where special preparation, welding or. -
inspection methods were necessary, or where engineering authorization was not provided via other mechanisms such as a DCA or CMC. This interpretation was included in Revision 2 of WES-029 (January 14, 1983).
p The interviews with inspection personnel (Reference 9.21)~ indicated that before November 1980 several methods had been used to document the inspection of plug welds in cable tray supports. Prior to the reassignment of responsibility for cable tray support inspection in December 1979, most plug weld inspections were documented using a QC accept sticker attached to O the support or by the inspector marking his initials and date on the support near the weld. Af ter December 1979 and prior to November 1980, plug weld inspections were documented using an inspection report. Use of the inspection report was in compliance with the procedures in effect at that time. However, the third-party has not been able to identify any procedure which a
, authorized the use of QC~ accept stickers or inspector initials on the support as the only record of inspection. The use of QC accept stickers was required by procedure QI-QP-11.3-24 (Revision 0) . However, it does not appear that this procedure applied to cable tray support veld inspections. Furthermore, this procedure also required that Class 1E cable tray raceway inspections be documented on an inspection report in accordance with procedure CP-QP-18.0.
1 The information provided by these interviews is
, consistent with the results of the reinspections and document reviews performed by the third-party under this action plan. All the plug welds found in the records of the 120 supports in the random sample were documented on construction operation travelers and/or inspection reports. Thus, the ROD /RPS, if used, was a very infrequent method of documenting the repair of mislocated holes in cable tray supports. In additior.,
l 1
O no undocumented plug welds were found in supports for which the construction operation traveler was signed by i
5_ .-, -
Revision: 1 Page 24 of 57 RESULTS REPORT ISAP V.d
, (Cont'd) 5.0 IMPLEMENTATION OF ACTION PLAN AND DISCUSSION OF RESULTS (Cont'd)
QC after December 1979. This corresponds to the date when the responsibility for cable tray supports was assigned to a new inspection group and the interviews indicate that inspection reports, rather than QC accept stickers, were used to document plug weld inspections.
Based on this review, the third-party concluded that the current procedural requirements for the inspection and documentation of the repair of mislocated holes in cable tray supports are adequate and in compliance with QA prcgram and licensing commitments.' With respect to the previous procedural requirements, the third-party concluded that the fact that an ROD or RPS was not generally issued for the repair of mislocated holes in cable tray supports is not a deviation from QA program or licensing commitments. Since these welds were authorized by DCA-5347, documenting their inspection in O' the same manner as all other cable tray support welds (i.e., on a construction operation traveler or inspection report) was in compliance with the QA program.> However, the practice of using QC accept stickers or initials marked on the support as the only method of documenting the inspection of some plug welds prior to December 1979 is considered to be a violation of 10CFR50, Appendix B, Criterion XVII (Quality Assurance Records) in that it resulted in a condition where no retrievable inspection record exists for some plug welds in cable tray supports. This discrepancy was documented in DIR-D-2177 and classified as a deviation. This DIR was determined to be not safety-significant on the basis that all of the plug welds found during the reinspection met AWS DI.1 visual acceptance criteria, and, as discussed in Section 5.4, it is unlikely that the undocumented plug welds have adversely affected the structural integrity of the supports. This DIR has been transmitted to the QA/QC Program Adequacy Review Team for trending under that program (Reference 9.22).
5.3.3 Other Components Table 3 lists the component types, or commodities, other than cable tray supports where the repair of g mislocated holes was authorized. With the exception of HVAC supports these commodities were fabricated and/or
~b _ _ __ ___'___ _
Revision: 1 Page 25 of 57 RESULTS REPORT ISAP V.d
, (Cont'd) 5.0 IMPLEMENTATION OF ACTION PLAN AND DISCUSSION OF RESULTS (Cor.t'd) installed and inspected by Brown & Root. The HVAC supports, which are addressed later in this section, were fabricated, installed and inspected by the Bahnson Service Co.
The primary construction and inspection procedures involved are also listed in Table 3. The third-party has reviewed over seventy procedures, excluding revisions, which over time have addressed some aspects related to the repair of mislocated holes (Reference 9.23). In general the CP-QCI and CP-QCP series'of inspection procedures were originated in 1976 and were superseded by the existing CP-QP and QI-QP series in 1978. The corresponding Brown & Root construction procedures began in 1975 and evolved to their current revisions. Both the construction and inspection procedures reference construction specifications and Brown & Root welding standards for the general O requirements related to welding. While there have been changes to these procedures, specifications and standards related to the authorization for the repair of mislocated holes and the methods of documenting these repairs, the basic requirements for making and inspecting plug welds have consistently included the following:
Visual inspection of all welds in accordance with the requirements of AWS D1.1 (either by reference or by inclusion of the inspection criteria in the procedure).
Use of qualified welding procedures.
Use of qualified welders.
Fabrication, welding and installation to approved drawings and other documents including design change documents.
Documentation of weld inspections via Construction Operation Travelers (C0Ts),
Inspection Reports (irs), Weld Inspection Documentation Cards, Repair Process Sheet (RPSs) or checklists.
i
- h ,---. - -- . -_ - - .-- - - - - - - - . - - - - - - - - - - - - - - - - - -
Revision: 1 Page 26 of 57 RESULTS REPORT V[Y ISAP V.d (Cont'd) 5.0 IMPLEMENTATION OF ACTION PLAN AND DISCUSSION OF RESULTS (Cont'd)
Before 1978, various component checklists were used to document weld inspections. Since 1978 the IR, the COT and the RPS have been the principal records for documenting weld inspections by Brown & Root. It was noted that several of the cable tray and conduit raceway inspection procedures in effect prior to January 1984 address the use of QC acceptance stickers.
While these procedures required the use of an IR to document inspections discussions with a Brown & Root inspector (Reference 9.24) who performed plug weld inspections on cable trays indicated that in the late 1979, early 1980 time period the practice of using QC acceptance stickers to document plug weld inspections also extended to cable trays.
The welding of mislocated holes and the associated inspections have been addressed by both commodity 7s specific procedures e.g., QI-QP-11.10-1A (Inspection of
(\ Class IE Conduit Raceway System) and generic procedures e.g., QI-QP-11.21-1 (Requirements for Visual Weld Inspection). In addition, the repair of mislocated holes has been described in various procedures as the repair of base metal defects, repair welding or its own unique activity, i.e., plug welding of mislocated holes. However, the general treatment regarding visual inspection, qualified welding procedures and welders '
and fabrication and inspection in accordance with the design documents has remained the same.
Furthermore, since August 1975, the Project has had procedures (WCP-5) in place to control weld filler material and its proper selection and use with the various base materials. As can be seen from Table 3 the principal base metals in which plug welds were mada have been A-36 and other Group 1 & 2 carbon steels.
The filler metals used for these welds have been E7018 and E70S-2.
As of October 1986, the Bahnson procedures do not explicitly address repair welding of mislocated holes.
This subject is being incorporated in Revision 6 of their general repair procedure, GRP-TUSI-001. However, as with other commodities the key elements were included in the Bahnson procedures which govern the O, fabrication, installation and inspection of HVAC supports. Specifically, the following requirements related to welding have been included in the Bahnson l procedures since 1978:
h _. - - - - - - - - - - - - - - . _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
_( - - _ - -
Revision: 1 Page 27 of 57 RESULTS REPORT ISAP 7.d
, (Cont'd) 5.0 IMPLEMENTATION OF ACTION PLAN AND DISCUSSION OF RESULTS (Cont'd)
Visual inspection in accordance with AWS 91.1.
{
Use of qualified welding procedures.
i Use of qualified welders.
Fabrication, welding and installation in '
accordance with design documents.
Use of proper weld filler metal for the base metal being welded.
Documentation of weld inspections on duct supporc inspection checklists.
Surveillance of weld filler metal control practices by a Quality Representative.
Based on the results'of these reviews, it was concluded that the procedural requirements associated with the repair of mislocated holes and their inspection
- and documentation are adequate. The review did identify inconsistencies in several procedures relative to the criteria for allowing unused holes to remain unwelded.
These inconsistencies were documented and are discussed further in Section 5.7.
The third-party also reviewed the construction and inspection records for selected components as indicated in Table 3 (Reference 9.25). The results of this review indica 6ed that the repair of mislocated holes in these components was properly authorized, utilized
( qualified weldere and welding procedures, and the welds were inspected and documented in accordance with applicable procedures. However, as noted previously, the practice of using QC acceptance stickers to document plug weld inspections (see Section 5.3.2) also extended to plug welds in cable trays during the same ,
time period (i.e., late 1978 to early 1980). Thus,
! some undocumented plug welds exist in cable trays. The frequency of-undocumented plug welds in cable trays is expected to be less than observed in cable tray O supports on the basis that cable tray is installed after the cable tray supports and the use of QC acceptance stickers to document plug veld inspections was discontinued early in the process of accepting cable tray supports.
.A -
. ;~
Revision: 1 PaFe 28 of 57 RESULTS REPORT ~
O> ISAP V.d i (Cont'd) 5.0 IMPLEMENTATION OF ACTION PLAN AND DISCUSSION OF RESULTS (Cont'd)
Based on the above reviews, it was concluded that the repair of mislocated holes in commodities listed in-Table 3 was treated in a manner comparable to the repair of mislocated holes in cable tray supports.
Thus, the results of the evaluation of plug welding in cable tray supports are considered to be applicable to these commodities and no reinspection of the plug welds in these commodities is necessary.
5.4 Bounding Evaluations The TRT requested that TUGC0 perform sample inspections of cable tray supports, pipe supports and base plates for plug weld quality or perform bounding analyses of the generic effects of uncontrolled plug welds on the structural integrity of these components. As discussed in Section 4.0, this action I
plan utilized a combination of both approaches, in order to provide additional assurance that plug welding practices at 1
CPSES did not adversely affect the structural integrity of support members.
5.4.1 Evaluation of the Effect of Weld Quality on Weld Strength 1
l 1
As discussed in Section 3.0, TUGC0 presented test data during the ASLB Hearings that indicated that, using normal welding techniques, significant amounts of slag would not be entrapped in the weld, and that even with large amounts of slag in the weld, the test specimens i
exceeded the tensile strength requirements of the base metal.
In the interest of further exploring the possibilities of slag entrapment, it was decidad that additienal tests using CPSES welders, selected at r.2ndom, would add confidence to conclusions drawn from earlier wasts.
Three welders were selected at random from the list of 138 welders at CPSES who were currently qualified for the welding procedure used to make plug welds (WPS-10046). Each welder made eight 3/4-inch-diameter plug welds in 3/8 inch thick A36 plate coupons using the welding parameters specified in WPS 10046. Four of these plug welds were made with the aid of a pencil grinder to remove slag and four were made using only a i
. (. - __ . .
4 + \ s T i
@ p; .
Revis t'en: 1 Page 19 of 57
,i g - ,
3 1
.t 1
~ .
O' RESULTS REPORT 1
D '
('
. ISAP V.d i s - (Cont'd) ,
)
5.0 IMPLEMENTATION OF ACTION PLAN AND DISCUSSION OF RESULTS (Cont'd) 4 ' A.
chipping hammer and wire' brush. One veld coupon of each type was' selected.ifor metallographic examination and the other three of'each type'of. weld coupons pece subjected to tensile tests. This provided a total (of six metallography coupons and 18 tensile test coupons. ~
The results of these tests, Reference 9.26, confirb'd 4
the basic original conclusions in that_all 18 specimens i
' tested exceeded the minimum yield and tensile strength l of the base metal. The tests did indicate that
{
grinding is more effective than chipping and tire .
'N brushing alone in preventing slag entrapment. Hewever, r' i
.i- with both weld cleaning techniques the required r '
i strengths were obtained. \ ' ' l' s
Based on the above, it can be concluded that fo'r the .
3'
( geometry of a typical plug weld, usir.g a suitable
," welding procedure, sufficient, slag'will not be Oi' s
,, entrapped to reduce the Strength of the welded section
' i to less than the minimum required of the base metal.
Visual inspection and acceptance of plug welds in the 1 ground condition airo.provides e"idence that the weld' y j will meet the applicable strength requirements.
~
'i
' i
'c 5.4.2 Evaluation of the Structural Significance o* Holes in hY' Cable Tray and Cable Tray Supporta; t i .s Cable Tray Supports -
s Since plug welds in cable traf supports werc made to N
repair mislocated holes, sn assessment of the structural significance of a poor quality plug wsld can y be obtained by considering the significance of ;nn',
, j unwalded hole at the same location.
,[ As par't of, the cable tray support requalification
,i program Ebysco has performed e sample inspection of the
'l v ,
size of used and unused holes in cable tray supports
' and their base plates (Reference 9.27). The results of
' this inspection were evaluated by the third-party to estimate the size of holes that may have been plug
^ welded (Reference 9.28). Table 6 summarizes the
. results of this evaluation. As. can be seen fror.a d Table 6 most (96%) of the anchor bolts are 1" or 1-1/4"
' ' in diameter and all of the member bolts are 5/8" or 3/4" in dipmeter. The size of the plug welds are equal
i Ravision: 1 Page 30 of 57 RESULTS REPORT ISAP V.d (Cont'd) 5.0 IMPLEMENTATION OF ACTION PLAN AND DISCUSSION OF RESULTS (Cont'd) to the bolt size plus the normal bolt hole clearance and any fabrication variation. Thus, for base plates most plug welds are expected to be in the range of 1-3/16" to 1-7/16" in diameter with a maximum diamatar slightly more than 1-5/8". For the support members
, most of the plug welds are expected to be 11/16" to 13/16" in diameter with a maximum size slightly more than 13/16".
The inspections performed by Ebasco determined the actual size of each used and unused hole in the sample.
Thus these data can be used to estimate the largest hole that may have been welded. As shown in Table 6-the largest anchor bolt hole found was 1-11/16". The
' statistical evaluation of the anchor hole size data (Reference 9.28) indicated that at the 95% confidence level less than 1.32% of the supports have anchor holes larger than 1-11/16". The largest support member hele O found was 29/32". The statistical evaluation of the support member hole size data indicated that at the 95%
confidence level less than 1.32% of the supports have holes in the support members larger than 29/32".
The design basis provided in DCA-5347 and substantiated by Ebasco (See Section'5.2.1) for cable tray supports allows for unused holes up to 3/4" in diameter in the support members that meet the spacing criteria from other used or unused holes as shown in Figure 1. Since the plug welds in support members are expected to be in the range of 11/16" to 13/16" with an expected maximum size of 15/16", it is considered extremely unlikely that a poor quality plug weld would be more limiting than a 3/4" hole which is permitted in most regions of the member (see Figure 1). In those cases where the r plug weld is located close to another used or unused hole, a poor quality plug weld would be more critical.
However, based on the results of the weld tests discussed in Section 5.4.1, even plug welds with significant slag inclusions are expected to exhibit strengths comparable to the base metal. Therefore, it was concluded that the presence of a poor quality plug weld in a cable tray support member was very unlikely to compromise the structural integrity of the support.
O s
, , __ ___ .. .--- . - ,----,----t-- '-
Rsvision: 1 Page 31 of 57 RESULTS REPORT ISAP V.d (Cont'd) 5.0 IMPLEMENTATION OF ACTION PLAN AND DISCUSSION OF RESULTS (Cont'd)
To assess the potential effects of a poor quality plug weld in a cable tray support base plate, Ebasco evaluated the effect of a 1-11/16" hole located in the region of maximum bending stress (Reference _9.29). The results of this evaluation indicate that the hole will not cause any significant increase in the stress levels in the plate.
Cable Trays Misdrilled holes in cable trays are repaired by depositing weld material by the Gas Tungsten Arc Welding (GTAW) process, with E70S-2 (electrode material) cold wire feed. The weld metal so deposited will have a nominal yield of 60 KSI aid a tensile strength of 72 KSI (stronger than the base metal).
GTAW is an inert gas shield process in which slag in not produced. Porosity is the major discontinuity 8
which can occur and its presence will cause cross sectional reduction proportional to its size. Because cable trays are fabricated from thin material (sheet metal), significant porosity will be visible in the welded surface and corrective action.can be taken if the surface fails to pass the visual examination criteria for AWS DI.l.
To assess the effect of an unplugged hole on the structural integrity of the cable trays, Ebasco performed an analysis. The result of the analysis indicates that an unplugged hole would have no effect on the integrity of the cable tray provided 1) the hole is not larger in diameter than that required for a 5/8 inch bolt, and 2) the edge-to-edge distance to the nearest used or unused hole is not less than the diameter of the unplug:;ed hole.
The analyses discussed in this section have been incorporated into the Ebasco cable tray requalification program and are being evaluated by third-party as part of the implementation of DSAP VIII overview activities of that program.
O g
i Revision: I
, Pags 32 of 57 RESULTS REPORT ISAP V.d (Cont'd) 4 5.0 IMPLEMENTATION OF ACTION PLAN AND DISCUSSION OF RESULTS (Cont'd) 5.4.3 Implication of Bounding Evaluations The results of the document reviews and procedure reviews indicated that the repair of mislocated' holes was authorized, that the welds were made with the proper filler metal using qualified welders and welding procedures, and that they were inspected in accordance with the requirements of AWS D1.1. However, as discussed in Section 5.3.2 and 5.3.3 there was a practice early in the Project of using QC ace'eptance stickers to document plug weld inspections in cable tray and cable tray supports which resulted in no
, permanent inspection record for some plug welds.
The extent of this practice was quantified by the cable tray support inspections which indicated that 6.9%,of the cable tray supports have one or more plug welds for i'
which weld inspection records are no longer available.
These inspections also indicated that no undocumented plug welds were found on supports initially accepted by QC after December 1979 and that all plug welds found, both documented and undocumented, meet AWS DI.1 visual inspection criteria. Thus, the lack of permanent plug weld inspection records appears to be limited to a small portion of the population and did not adversely i reflect on the quality of the plug velds.
The bounding evaluations described in Sections 5.4.1 and 5.4.2 provide additional confidence that the undocumented plug welds not reinspected under this action plan are very unlikely to compromise the structural integrity of the components involved. Thus, based on the results of the investigations performed under this action plan, it is concluded that there is reasonable assurance that the existence of undocumented plug welds is not safety-significant.
5.5 Safety Significance Evaluation The original concern identified by the NRC (DIR-E-0348) related to the possible existence of unauthorized.
-undocument'ed and uninspected plug welds in pipe supports, cable tray supports and their base plates. The investigaticas
' performed under this action plan determined that the repair of mislocated holes was not authorized in ASME pipe supports or s their base plates and no plug welds were found. The repair of mislocated/ unused holes was authorized by Engineering for
_lk__ - -- i - . - - - - - - - -- -- ----- -- - ~
1 Revision: I Page 33 of 37 RESULTS REPORT ISAP V.d j
(Cont'd) 5.0 IMPLEMENTATION OF ACTION PLAN AND DISCUSSION OF RESULTS (Cont'd) cable tray supports and a number of other AISC components.
The applicaole construction and inspection procedures have i
i consistently required that these welds be made using qualified welders and weld procedures and inspected in accordance with the AWS D1.1 visual examination criteria.
The investigations performed under this action plan also determined that prior to December 1979 there was a practice of using QC acceptance stickers or inspector initials marked on the support as the only record of plug veld inspections of cable tray supports and that this practice also extended to the inspection of plug welds in cable trays. Thus, the NRC concern is partially substantiated in that some plug welds exist for which the record of inspection is no longer available.
All undocumented plug welds found during the cable tray support inspections met the visual examination criteria of AWS D1.1. Thus, the lack of permanent inspection records for the six (6) supports which were found to contain undocumented plug welds (DIR-D-2177) was determined to be not-safety-significant. Further, the evaluations performed under this action plan indicate it is very unlikely that the undocumented plug welds that were not reinspected under this action plan could compromise the structural integrity of the components (see Section 5.4.3). Therefore, it was concluded 1
that the practice of using QC acceptance stickers or inspector initials marked on the support as the only record of
- inspections for some plug welds in cable tray and cable tray
- supports is not safety-significant.
i Since the only aspect of the original concern identified by the NRC that has been substantiated relates to the existence l of undocumented plug welds, DIR-E-0348 was transferred to l DIR-D-2177 which addresses this issue. DIR-D-2177, which is classified as a deviation, has been transmitted to the QA/QC Review Team for trending under that program (Reference 9.22).
I 5.6 Root Cause and Generic Implications The investigations performed under this action plan did not identify any deficiencies or adverse trends. Thus, an evaluation of root cause and generic implications is not {
required by the CPRT Program Plan.
t O
L e 9
-_._.._,_m___._N_,.._____,__.._..____._._.,,,,__,..,.,,,m.,_.,_.__.,,.,.._,,.,,_.-y.-,_w__-.~.-__-._._,._
Revision: 1 Page 34 of 57
/ RESULTS REPORT k
ISAP V.d (Cont'd) 5.0 IMPLEMENTATION OF ACTION PLAN AND DISCUSSION OF RESULTS (Cont'd) 5.7 Out-of-Scope Findings The purpose of the investigations performed under this action plan was to evaluate concerna related to the adequacy of welds made to repair mislocated or unused holes. In the process of these investigations, the following discrepancies associated with the criteria that specify which unused holes can remain unwalded were identified:
DIR-D-0018 As discussed in Section 5.2.1, this DIR was issued to document the fact that criteria in DCA-5347 (Revision 0 and 1) specifying which holes could remain unwelded were not clearly stated, and the justification was not adequate for allowing holes up to 3/4" in diameter to remain unwelded. This DIR was classified as a deviation and determined to be not s a'f e ty-significant.. A new DCA (No. 25028) has been issued to
/ clarify the criteria.for the repair of mislocated/ unused
\s,)'
holes. Further, the presence of unused holes up to 3/4" diameter is being addressed by Ebasco in thw reanalysis of the cable tray support system. Since the lack of clarity in DCA-5347 has been corrected and the implementation of the cable tray requalification program is being overviewed by the third-party under DSAP VIII, no further action under this ISAP is necessary. DIR-D-0018 has been revised to transfer the responsibility for closure to DSAP VIII.
DIR-D-2201 and DIR-D-2202 2
These DIRs were issued to document the fact that unused bolt holes in instrument tube supports and conduit supports were not included in the evaluation of the individual supports and no generic justification was provided. The Project is currently evaluating the significance of unused bolt holes in these supports. Third-party overview of these Project evaluations has been included under the Design Adequacy Program. Therefore, DIR-D-2201 (Unused Holes in Instrument Tube Supports) has been transferred to DSAP IX (Piping and Supports) and DIR-D-2202 (Unused Holes in Conduit Supports) has been transferred to the DSAP VIII (Civil / Structural) for classification and closure.
O 4
Revision: 1
, Page 35 of 57 RESULTS REPORT
-O ISAP V.d (Cont'd) 4 5.0 IMPLEMENTATION OF ACTION PLAN AND DISCUSSION OF RESULTS (Cont'd)
DIR-C-0097 The criteria specifying which unusad holes can remain unwelded in cable tray, cable tray supports and conduit supports evolved with time and several inconsistencies in incorporating these criteria in the construction and inspection procedures were encountered in the procedure reviews performed under this action plan. In all three areas the Project was aware of such concerns and is in the process of initiating corrective actions which should assure that the proper criteria have been applied. Third-party overview of these corrective actions will be tracked under DIR-C-0097.
6.0 CONCLUSION
S The investigations performed under this action plan determined that the repair of mislocated holes was not authorized in ASME pipe supports and their base plates and there is reasonable assurance that no plug welds are present. The repair of mislocated/ unused holes was authorized for cable tray supports and a number of other AISC components. The applicable construction and inspection procedures have consistently required that these welds be made using qualified welders and weld procedures and inspected in accordance with the AWS DI.1 visual examination criteria.
The investigations performed under this action plan also determined that prior to December 1979 there was a practice of using QC acceptance stickers or inspector initials marked on the support as the only record of plug weld inspections of cable tray supports and that this practice also extended to the inspection of plug welds in cable tray. Thus, some plug welds exist for which the record of inspection is no longer available. This discrepancy was considered to be a violation of 10CFR50, Appendix B, Criterion 16 (Quality Assurance Records). It has been classified as a deviation and transmitted to the QA/QC Review Team for trending under that program.
Based on the results of the inspections, procedure reviews and bounding evaluations performed under this action plan, it was concluded that there is reasonable assurance that undocumented plug welds not reinspected under this actica plan will not compromise the structural integrity of the components.
O 8
3 Revision: 1 Page 36 of 57 f"N RESULTS REPORT
\
ISAP V.d
. (Cont'd)
6.0 CONCLUSION
S (Cont'd)
The investigations performed under this action plan also concluded that adequate justification was not provided for the criteria which permit unused bolt holes to remain unwalded in cable tray supports, conduit supports and instrument tube supports. The cable tray support requalification program has already included the evaluation of unused bolt holes and the Project is assessing the signi.cance of unused holes in instrument tubing and conduit supports. These discrepancies have been transferred to the Design Adequacy Program for fellow-up.
7.0 ONGOING ACTIVITIES There are no ongoing activitiec related to the welding of mislocated holes. However, three discrepanciec related to the justification for allowing unused holes to remain unwelded (DIR-D-0018 DIR-D-2201 and DIR-D-2202) have been transferred to
/~ the Design Adequacy program for follow-up and closure. In (s_- addition, DIR-C-0097 was issued to track the third-party overview of the Project corrective actions _ related to the implementation of the unused hole criteria in the inspection procedures for cable tray, cable tray supports and conduit supports.
8.0 ACTION TO PRECLUDE RECURRENCE The current procedures and practices for the repair of mislocated holes, including their inspection and documentation are adequate to preclude the recurrence of undocumented plug welds.
9.0 REFERENCES
9.1 NUREG-0797 Supplement 10, April 1985 (SSER-10), " Safety Evaluation related to the Operation of the Comanche Peak Steam Electric Station, Units 1 and 2".
9.2 ASLB Hearing Transcript dated February 23, 1984 9.3 ANSI /AWS A3.0-80 " Welding Terms and Definitions" 9.4 Addendum to Page 27 of NRC Staff Testimony on Welding Fabrication Concerns [TR: 12146]
() 9.5 ASLB Hearing Transcript (TR: 11632-33]
w _--- - - -
Revision: 1 Page 37 of 57 RESULTS REPORT ISAP V.d (Cont'd)
9.0 REFERENCES
(Cont'd) 9.6 ASLB Hearing Transcript [TR: 11781]
9.7 Brown & Root Specification WES-029, Revision 2 (January 14, 1983) " Welding Specification for Field Fabrication and Erection of Structural Steel" 9.8 ASLB Hearing Transcript, Applicants' Exhibit 177 pages 42-44 9.9 ASLB Hearing Transcript, NRC Staff Testimony page 26 [TR:
12,146]
9.10 ASLB Met 1orandum Concerning Welding Issues (LBP-84-54),
December 18, 1984 pages 77-78 9.11 ERC inspection procedure QI-007 for plug weld inspections 9.12 Memo J. R. Honekamp to V.d File "Sununary of Inspector Testing for the Location of Plug Welds" May 29, 1986 9.13 Memo IM #29082, W. E. Baker to Claude Moehlman " Plug Weld Sampling and Inspection" November 20, 1985 9.14 ERC Memo QA/QC-RT-200, " Population Items List: Large Bore Pipe Supports", July 3, 1985 9.15 Memo R. L. Shipp to Harold Porter "Randon Sampling for Plug Welds", July 31, 1985 9.16 TERA Memo Sanan to ISAP File V.d " Methodological Errors in Support Sampling Related to ISAP V.d", November 17, 1986 9.17 ERC inspection records for both the inspections of cable tray and pipe supports. (File V.d.5.c) 9.18 TERA Memo R. T. Woolheater to R. K. Sanan, " Pipe Support l Packages", October 7, 1986.
9.19 TERA Engineering Evaluation V.d.4b.1, Revision 1. " Evaluation of DCA 5347 Revision 1".
9.20 TERA Memo ISAP-L-002, J. R. Honekamp to ISAP V.d File, October 9, 1986.
9.21 Memo John R. Honekamp, to V.d File - Plug Welds O " Interviews with Personnel Involved in the Inspection of Plug Welds in Cable Tray Supports Prior to November of 1980",
October 17, 1986.
g ._
Revision: I Page 38 of 57 RESULTS REPORT ISAP V.d j
(Cont'd)
9.0 REFERENCES
(Cont'd) 9.22 DAP/QOC Interface Transmittal S-1080, October 1, 1986.
9.23 TERA Memo D. C. Timmins to J. R. Honekamp. "ISAP V.d - Review of Applicable Specifications and Procedures", October 7,1986.
i-9.24 CPRT TRT/DAP Contact Log Sheet documenting a telecen between Doug Timmons (TERA) and Mike Uptmore (B&R) relative to plug i
welding of cable trays, 10/30/86.
9.25 TERA Memo from D. C. Timmons to J. R. Honekamp, "ISAP V.d -
Construction / Inspection Documentation Review", 10/15/86.
9.26 Test Report "The Metallurgical and Structural Significance of i
~
' Plug Welded' Holes in Cable Tray Supports - ISAP V.d (Comanche Peak Steam Electric Station), C. D. Lundin, November ~
24, 1986.
9.27 Ebasco Memo EB-RCI-0239, R. C. Iotti to C. K. Moehlman, g "Results of Bolt Hole Edge Distance Investigation",
(,,j October 20, 1986.
9.28 Memo CPRT-718, F. Webster to J. Miller, dated November 20,
' 1986 " Statistical Analysis of Bolt-Hole Sizes in Cable-Tray Hangers - Issue V.d".
9.29 Ebasco Memo SAG. TUG 2.2449. R. Alexandru and L. Gorozdi to E. Odar, ' Unused Bolt Holes in 1" Four Bolt Anchor Plate',
February 3,1986.
i l
y I
e 4
- . O 4
I 6---.---...-------
- - - - - - - - - - - - --- - - ~ '
Revision: 1 Page 39 of 57
- f-- RESULTS REPORT ISAP V.d (Cont'd)
Table 1 Results of Ca' ale Tray Support Document Reviews and Inspections Number of Cable Tray Supports in the Sample 120 Document Review Results:
Number of Supports With Documented Plug Welds 30 Number of Documented Plug Welds 65 Number of Accessible Documented Plug Welds 56
% of Documented Plug Welds Accessible (56/65) 82.6 Inspection Results:
Weld Basis:
Total Number of Plug Welds Detected 57 Number of Documented Plug Welds Detected 47 Number of Undocumented Plug Welds Detected 10
% of Accessible Documented Plug Welds Detected (47/56) 83.9
% of Plug Welds Found That Were Documented (47/57) 82.5 Support Basis:
Total Number of Supports With Plug Welds 26 Number With All Plug Welds Documented 20 Number With One or More Undocumented Plug Weld 6
% of Supports With One or More Undocumented Plug Welda (6/120) 5 O
- s. L
Rr,vief on: 1 P g:a 40 of 57 RESUI.TS REPORT ISAP V.d (Cont'd)
Table 2 Summary of Cable Tray Supports With Plug Welds Initial Support Original Plug Plug Weld QC Acceptance Plug Weld Weld Inspection Found by Support Number Unit # On the COT
- Number Record and Dat'e Comments QA/QC Review Team CTH-1-61 1 & COMMON 03/24/80 01 COT
- 10/05/83 NO 02 COT 10/05/83 YES 03 COT 11/02/83 NO FSE-00159-338 1 & COMMON 02/12/79 01 COT 09/01/83 YES 02 COT 09/01/83 YES FSE-00159-1831 1 & COMMON 04/04/79 01 COT & IR* 06/27/83 YES NONE YES NOTE I FSE-00159-2372 1 & COMMON 02/02/79 01 IR 12/04/79 YES 02 NONE YES NOTE I FSE-00159-3785 1 & COMMON 02/07/79 01 RCOT* 02/19/84 YES 02 RCOT 02/19/84 YES 03 RCOT 02/19/84 YES 04 RCOT 02/19/84 YES FSE-00159-4045 1 & COMMON 02/08/79 01 RCOT 02/18/84 YES 02 RCOT 02/18/84 YES FSE-00159-4142 1 & COMMON 02/08/79 01 NONE YES NOTE 1 FSE-00159-4182 1 & COMMON 02/19/79 01 NONE YES NOTE 1 -f4 O O O
R; vision: 1 P;g2 41 of 57 RESULTS REPORT ISAP V.d (Cont'd)
Table 2 (Cont'd)
Initial Support Original Plug Plug Weld QC Acceptance Plug Weld Weld Inspection Found by Support Number Unit # On the COT
- Number Record and Date Comments QA/QC Review Team FSE- 00159-4262 1 & COMMON 01/30/79 01 RCOT 02/28/84 YES 02 RCOT 02/28/84 YES 03 RCOT 02/28/84 YES 04 RCOT 02/28/84 YES 05 COTW* 03/18/83 YES 06 YES 07 NO 07 NO FSE-00159-4292 1 & COMMON 02/14/79 01 IR 09/25/79 YES 02 IR 09/25/79 YES FSE-00159-4300 I & COMMON 02/08/79 01 RCOT 02/20/84 YES 02 RCOT 02/20/84 YES 03 RCOT 02/20/84 YES 04 RCOT 02/20/84 YES FSE-00159-4328 i & COMMON 02/08/79 01 COT & IR 07/13/83 YES 02 RCOT 02/24/84 YES 03 RCOT 02/24/84 YES 04 NONE YES NOTE 1 05 NONE YES NOTE 1
. FSE-00159-5230 1 & COMMON 02/01/79 01 COTW 11/30/83 YES
.se O O O
R;vicinn: 1 Pcg2 42 of 57 RESULTS REPORT ISAP V.d (Cont'd)
Table 2 (Cont'd)
Initial Support Original Plug Plug Weld QC Acceptance Plug Weld Weld Inspection Found by
__ Support Number Unit # On the COT
- Number Record and Date QA/QC Review Team Comments CTII-1-6167 I & COMMON 03/17/80 01 COT & IR 07/10/83 YES 02 COT & IR 07/10/83 YES 03 COT & 1R 07/10/83 NO 04 COT 01/04/79 YES FSE-0159-6485 I & COMMON 04/30/79 01 COTW 11/10/83 YES 02 COTW 11/10/83 NO CTil-2-7175 2 08/09/82 01 COT & IR 11/11/85 YES FSE-0159-7271 2 03/20/82 01 COT 01/23/84 YES FSE-00159-7271 1 & C0KMON 07/19/80 01 COTW 07/06/84 YES 02 COTW 07/06/84 YES FSE-00159-8322 ' I & COMMON 11/28/79 01 NONE YES NOTE 1 02 NONE YES NOTE 1 03 NONE YES NOTE 1 04 NONE YES NOTE I FsE-00159-8558 1 & COMMON 06/25/80 01 COTW 07/27/84 YES 02 COTW 07/27/84 YES 03 COTW 07/27/84 YES 04 COTW 07/27/84 YES
-el FSE-00159-9887 2 08/28/80 01 COTW 03/I3/84 YES -
- 9 9 9
R vicion: I P:ga 43 ef 57 RESULTS REPORT ISAP V.d (Cont'd)
Table 2 (Cont'd)
Initial Support Original Plug Plug Weld QC Acceptance Plug Weld Weld Inspection Found by Support Number Unit i On the COT
- Number Record and Date QA/QC Review Team Comments FSE-00159-10,760 2 12/15/80 01 COTW 02/07/84 YES FSE-00159-10,161 2 03/19/80 01 COTW 02/14/84 NO 02 COTW 04/17/84 NO 03 COTW 04/17/84 YES FSE-00159-10,789 2 09/04/80 01 COT 10/20/81 YES FSE-00159-II,254 2 01/07/81 01 COTW 02/01/84 YES 02 COTW 02/01/84 YES FSE-00159-II,405 2 10/20/80 01 COTW 02/02/84 YES 02 COTW 02/08/84 YES NOTES
- COT = Construction Operation Traveler RCOT = Unit i Spreading Room Rework Traveler COTW = Traveler with Weld Inspection Data Card IR = Inspection Report NOTE I - Undocumented Plug Weld O O O ---
R; vision: 1 P;ga 44 of 57 RESUL15 RFJWT ISAP V.d (Cont'd)
Table 3 Stenary of Other Gxtponents with Pltg Welds OtM mTAT REThWRUC WEIDDE INSIYLTIm FABRICATION / EASE fille LPUSED AIJIl0RI7ATION IWXHURES PIOOIXRIS @NSIRUCITCN METAL MTAL 10IE TXXINENN PIOCEIJURES AUDWED JIfrTION K1XFS ITA 4343 kTS 10082 QI-QP-i l .10-1 EI:P-19 A36 E70S-2 ND WPS 10046 QI-QP-11.10-7 EU-19A A569 E7018 GESIRUCTICN PADWE (I) QI-QP-11.21-1 A570 REVIEWED (2) CP-QCI-4.3-3 -
J15-3617 (3) QI-QP-16.0-5 CP-Q@-2.13 CP-QCI-2.13.-l CP-QCP-2.17 E3H'IRICAL PANEL ira 3273 WPS 10fM6 QT-QP-16.0-5 CP-GM-7.3D A36 E70S-2 PO GN5*IRUCiTON PADWE IMRIE IN GASS ITA 20986 kTS 10082 QI-QP-l l . lO-l AISI-1010 E7018 REVIEWED IE ARFAS frA 7974 (1) QI-QP-I I .21-1 A569 CP2-ElDPEIFOl DCA 6549 (2) QI-QP-11. IO-7 DCA 3120 (3) QI-QP-l l .14-12 ira 7982 CP-QCP-2.13 ira 15619(a) CP-QCP-2.17 DCA 22199 CP-QCI-2.13-1 O m -2.17-1
, (a) F M ENERCDCY
'fe IMTITRY -
RK K LNIls e 9 9
R vision: 1 Peg 2 45 of 57 RESUI3S RFR FT ISAP V.d (Cxxit'd)
Table 3 (Cont'd)
GTEMhT DCDEIRI?C WFIDING INSPECTI(N FAIRICATION/ BASE FIIJJR tt0 SED AlflHRI7ATION 1100IXRES IR00TURES GESIRICTICN PfTAL ETAL 10LIS 000MNIS PFOGILRES ALIDED INSIRINFNTATION DWG FSI-00082 WPS 10046 QI-QP-I I .8-5 G-GM-7.3D A36 E7018 YES* INSPECTION RITORIS 6 INSITINFNT DWG FSI-00071 (1) QI-QP-I 1.8-2 CP-ON-9.10 SA-36
- PCT 100N REVIEWED TtTsI?C StT'IWN DWG 2323-I-00I (2) QI-QP-11.21-1 SA515GP55 10 BE IR-1252, 1457, 1458,
-002 QI-QP-16.O-5 EKD CISED DtE 1588, 2926 & 2928 O rc73029RO QI-QP-II .3-14 10 IPACIT 7NE-II-0071 QI-QP-II.8-1 0F INE-Il-0178 QI-QP-11.8-9 I)6TAIJATI(N 1NE-Il-0082 G-QCP-2.17 CP-QCP-2.13 G-QCI-2. I3-1 CP-QCI-2.17-1 QI-QP-11.!M rABIE TRAY DCA 4178 WPS 10046 QI-QP-16.0-5 ECP-10 A570&B E7(E-2 YES QRSIRUCTI(N PAGME fCA 25066 WPS-10082 QI-QP-II.21-1 EXP-10A REVIDED ITA 21244 (a) (1) QI-QP-11.10-2A G-ON-7.3E }0(a) T23rDCX-54 (2) CP-QCI-4.3-4 FEP-10B QI-QP-II.3-5 QI-QP-II .10-9 FtM EAIL DCA 22425 Wis-10046 QI-QP-11.21-1 CP-ON-7.3D A36 E7018 NO (DNSIEUCITON PAGA2S e ira 22704 (1) QI-QP-11.14-1 FA 36 REVIBED ira 18145 (2) QI-QP-16.O-5 CP2-MMUI-59 -8e (3) G-QCP-2.13 CP2-MMUI-30 -
O O O
R;visfon: 1 Prg2 46 of 57 IUSULTS RETURT ISAP V.d (Cont'd)
Table 3 (Cont'd)
ImrnnT FNGINF'ERING WBDING INSPECIT m FAIRICATIm/ IMSE FIIIIR LPUSED AITIl0RI7ATION IWXHlURES F100I1UR!3 GPSIRCTIN METAL PEIAL 10IIS D00NFNIS PIOCEIJURES AlHWED TURNADO IWFER CP-QCP-2.17 TRAMFS & Q1SSET T-QCl-2.13-1 PIATES (Cont'd) &-QCl-2.17-1 TORNADD IW TER DCA 20A09 WPS-10046 QI-QP-16.0-5 T-GM-7.3D A36 E7018 YES GNS110CIIM FRAPFS & Q1SSFT DCA 15029 (1) QI-QP-11.14-1 PKKA&S REVDWED ITA1TS IEG 2323-S-789(a) (2) QI-QP-11.14-3
' DCA 15952 (a) (3) QI-QP-11.21-1 ND(a) CP2-TVSGID-Ol(a)
CP-QT-2.13 T-83-324-8904 CP-QCP-2.17 T-QCl-2.13-1
&-QCl-2.17-1 Ik 2323-S-0910 WPS-10046 QI-QP-16.0-5 ECP-19 A36 E7018 YES GREIRICTIN OTMIIT SIIEFT C4a (1) QI-QP-il.21-1 IIP-19A PKKAGS REVIlWED SiTT W IS DWG 2323-S2-0910 (2) QI-QP-11.3-23A CP-CEM-7.3E -
C22ED7334 SEET G-Sa (3) QI-QP-II .10-1 C26807181 QI-QP-I I .10-1A QI-QP-l l . lO-4 CP-QCP-2.13 CP-QCP-2.17 e-Qct-2.17-1 CP-QCI-4.3-3 -f QI-QP-I I .3-2 .
O O O -
R; vision 1 Pcg2 47 cf 57 105t!LTS REIURT ISAP V.d (Cont'd)
Table 3 (cont'd)
(INNNNr FNCDHRING LT1 DING INSPELTION FAIRICATI(N/ BASE FIIIH INSED Alm 0RIZATION ITDCFIURES FHDCERRES (D61RLCIT(N ETAL ETAL IDII5 ,
D00NFNIS IPDCERRES AIIDWED IIVAC. SifPRRIS DDCR NO. BSC-127 BSC-12 QCI-GSf2M)ll DEP *1151-001 A526 E70S-2 ND*
BSC-20 A527 E70S-3 A36 E7018 (a) SIRtCRRAL STTIL DCA 1818 kTS 10046 Ql-QP-16.0-5 CP-CEM-7.3D A36 E7018 N0 (IM*TCTION ITA 2087 (1) QI-QP-I I .14-1 (IT-22 IDLE (2) QI-QP-II .14-3 MISFIT 10 (3) QI-QP-11.21-1 USERTS QT-QP-l l .14-5 G-QCP-2,13 CP-QCP-2. I7 T-QCl-2.13-1 CIMEl-2.17-1 (b) SIHL " " "
DCA 2W99 A36 E7018 NO CDEIRUCTKN T1ATFORM DCA 20854(a) YES(a) PNEAGS REVIEWED frA 22296(b) YES(b) Oft-2, IM1!, P-02 ITA 22193 (c) SITH.
(IMTCET(N " " "
ITA 22171 A36 E7018 10 cIfYrITD IDIE 1rA 20434
.e e G O
R; vision: 1
, Pcg2 48 of 57 RESUL15 RERRT ISAP V.d (Cat'd)
Table 3 (Cont'd)
GM ETNT RCINEFRDC WD DIIC INSPEUIT0N FAIRICATim/ PASE FIIllR IM1 SED AtmtmI7ATIm PanIxns n u m RES C361ECTIm PETAL PETAL HDES DOCuens PROQIXRFS All&ED (d) 1110 kT3DS IN DCA 20771 A36 E7018 to IF#1 kTP OF DrA 22474 PIATRRf DCA 20264 (e) PIA 1RRf DCA 14664 A36 E7018 PD SITH.
SAFH2 RED MIC.
(f) D.C.
Inan\ tim " " "
DCA 22537 A36 E7018 NO I1 ATE (g) MOIFICATION " " "
DCA 10357 A36 E7018 NO OF 11ATRMt -
(h) IMSE P! ATE " " "
DCA 22455 A36 E7018 PD 1110 kTIDS (f) S-1-STAT 1MAY DCA 15684 A36 E7018 NO UNsIRUCITN PAGA&S DCA 16622 REVIEHFD CS40-1027-8903 G-83-1057-8903
-t O O O
R;vfofon: 1 Pcg2 49 of 57 RFRUS REI0Kr ISAP V.d (Cont'd)
Table 3 (Cont'd)
(IMunT DCDMRING WFIDU C INSPELTION F/KICATION/ IMSE FT11 R IMHD Alm 0RIZAnm IWXHURES MUIURES CONSMUTION ETAL HETAL IGE DOOMNIS Pf0CEDURES A111NED
- Before Jt 1e 4,1986, Ikimson Service Co. ms not mittorized to leave taused holes. Historically, no tnised holes or related pits welds were associated with anJn fr.re merbers arti all taused holes in baseplates were pitg welds! to qualified weldire procedures. Criteria for snised holes is beirg placed in the Bahnson general repair procedure.
(I) Related requirements - WES-029 (2) Related requirenents - S52-OI-106B O) Related requirements - 2323-SS-16B N
.e; O O O
Revision: 1 Page 50 of 57 RESULTS REPORT ISAP V.d (Cont'd)
Table 4 Procedures Reviewed in the Course of Preparing Results Report V,b Fabrication Construction Procedures CCP-22 Structural Steel Erection CP-CPM-6.9 General Piping Procedure CP-CPM-6.9G Documentation for ASME Welding and Installation Activities CP-CPM-7.3D Welding and Related Processes i
CP-CPM-7.3E Cable Tray and Conduit )
Supp. orts CP-CPM-9.10 Component Support Installation ECP-10 Cable Tray & Hangers Installation ECP-10A Cable Tray & Hangers Installation Unit II ECP-10B Cable Tray & Hangers Unit II Cable Spread Room / Frame Room 134 ECP-19 Exposed Conduit / Junction Box and Hanger Fabrication and Installation Unit II ECP-19A Exposed Conduit / Junction Box and Hanger Fabrication and Installation Unit II G22 . 3I-001 General Repair Procedure Inspection Procedures CP-QCI-2.13-1 Inspection of Field Fabricated Miscellaneous Steel CP-QCI-2.17-1 Inspection of Installation of Miscellaneous Steel
+ _
Rcvision: !
Page 51 of 57 RESULTS REPORT I
ISAP V.d (Cont'd)
Table 4 (Cont'd)
CP-QCI-4.3-3 Exposed Conduit & Hanger Installation CP-QCI-4.3-4 Cable Tray & Hanger Installation CP-QCP-2.13 Inspection of Field Fabricated Miscellaneous and Structural Steel CP-QCP-2.17 Inspection of Miscellaneous 4
Steel Installations CP-CPSES-011 Visual Inspection of Weld Procedures CP-QP-18.0 Inspection Report QI-QP-11.03-2 Cable Tray Hanger Inspection QI-QP-11.03-5 Cable Tray Inspection 4
QI-QP-11.03-23A Class IE Conduit Receiving Inspection QI-QP-11.03-24 Class 1E Cable Tray Raceway
- Inspections
! QI-QP-11.08-01 Instrament and Tubing
- Installation Inspection QI-QP-11.08-02 Insp. of the Fab. of Instrumentation Supports &
Rack Assemblies QI-QP-11.08-05 Insp. of Instrument Tubing Fabrication, Installation and Instrument Installation QI-QP-11.08-06 Inspection of Instrumentation Tubing Installation QI-QP-11.08-09 Insp. of Instal. of
- Non-Nuclear Safety Instr.
Seismic Supports i
.he'__._...._.____.,____.,____..--_.___._,,__-__.-__.____._._____.___._
s 4
Rsvision: 1 Page 52 of 57 fL RESULTS REPORT ISAP V.d
-(Cont'd)
Table 4 (Cont'd)
QI-QP-11.10-01 Inspection of Seismic Electrical Support & Restraint Systems QI-QP-11.10-01A Insp. of Class 1E Conduit Raceway Systems QI-QP-11.10-02 Cable Tray Hanger Inspection QI-QP-11.10-02A Inspection of Unit 2 Cable Tray Supports QI-QP-11.10-04 Inspection of Seismically Mounted Conduit Supports QI-QP-11.10-07 Inspection of Fabrication and Installation of Misc.
Electrical Equipment and Related Supports QI-QP-11.10-09 Cable Tray Hanger "As-Built" Inspection / Verification QI-QP-11.14-01 Insp. of Site Fabrication and Inst. of Struct. & Misc. Steel QI-QP-11.14-03 Inspection of Structural / Misc.
Steel Welding QI-QP-11.14-05 Insp. of Platforms Installed in Seismic Category 1 Structures QI-QP-11.14-12 Reverification of Seismic Electrical Equipment Mounting Details QI-QP-11.21-01 Requirements of Visual Wald Inspection
)
QI-QP-16.00-05 Reporting of Base Metal Defects O
w _ - -. - - -
. . . . ~.
e Revision: 1 Page 53 of 57 fN RESULTS REPORT
.I ISAP V.d (Cont'd)
Table 4 (Cont'd)
Welding Procedures & Specifications 2323-SS-16B Structural Steel (Category 1)
BSC-12 Gas Metal Arc Groove Joints.
Carbon BSC-20 '
Shielded Metal Arc Groove &
Fillet, Carbon WES-029 Welding Spec. for Field Fabrication & Erection of Structural Steel WES-021 Welding Engineering Standard WPS-10045 Weld Procedure Specification WPS-10046 Weld Procedure Specification WPS-10082 Weld Procedure Specification WPS-11032 Weld Procedure Specification S-52.01-106B Welding Specification for Field Fabrication and Erection of Structural Steel
+ - -- .-- ---
k Revision: 1 Page 54 of 57
( RESULTS REPORT ISAP V.d (Cont'd)
Table 5 History of Inspection and Documsntation Requirements For the Repair of Mislocated Holes in Cable Tray Supports June 3, 1978 Procedure QI-QP-11.3-2 (Revision 0) covering the inspection of cable tray and conduit supports'was issued. By this_ time B&R welding specification S-52.01-106B (structural steel welding per AWS DI.1), B&R welding standard WES-021 (repair of base metal defects) and construction procedure ECP-10 for cable tray supports had also been issued. None of these procedureJ or specifications directly addressed the repair of mislocated holes. However, both the welding specification and the welding standard provided for the weld repair of base metal defects using the Resolution of Defects (ROD) form to authorize l and document the repair.
t
- August 8, 1979 DCA-5347 (Revision 0) was issued requiring the weld repair of mislocated holes in cable tray
}~ supports that do not meet the stated spacing criteria.
i August 13, 1979 B&R specification S-52.01-106B modified to use the RPS instead of the ROD form to authorize and document weld repairs of base metal defects.
i December 1979 Inspection procedure QI-QP-11.3-2 (Revision 9) was repleced by procedure QI-QP-11.3-24 (Revision 0).
Several weeks later the inspection responsibilities for cable tray supports were transferred to a new group. The scope of procedure QI-QP-11.3-24 was modified to cover only the inspection of cable tray and a new procedure, QI-QP-11.10-2 was issued for the inspection of cable tray supports. Revision 0 of QI-QP-11.10-2 was essentially identical to Revision 9 of j QI-QP-11.3-2 which it replaced.
January 17, 1980 B&R Senior Project Welding Engineer issued memo i
IM #18507 dated 01/17/80 clarifying the
- requirements for welding mislocated holes in cable tray supports and instrument racks.
O i
i A
i Revision: 1 Page 55 of 57 RESULTS REPORT k
ISAP V.d (Cont'd)
Table 5 (Cont'd)
November 10, 1980 Revision 2 of QI-QP-11.10-2 was issued which included the criteria from DCA-5347 for plug welding unused holes plus the requirement for documenting these plug welds on the construction operation traveler.
August 4, 1981 B&R welding specification WES-021 was replaced by WES-029.
i January 14, 1983 Revision 2 of WES-029 provided specific direction for the repair of mislocated holes and stated that preparation of an RPS was not required for holes repaired in accordance with the specified technique.
l l
l l
i l
O
. s - __ - ---_ - - - -
Revision: 1 Pags 56 of 57 RESULTS REPORT ISAP V.d (Cont'd)
Table 6
SUMMARY
OF CABLE TRAY HOLE SIZE EVALUATION Distribution of Bolt Sizes in the Sample Inspected Bolt Size (inches) 1/2 5/8 3/4 1, 1-1/4 1-1/2 Anchor Bolts 1% 0% 0% 19% 77% 3%
Member Bolts 0% 67% 33% 0% 0% 0%
Results of Hole Size Inspections No. of Supports Largest Hole Found Used Anchor Bolt Holes 213 1-11/16" Used Member Bol? Holes 133 29/32" Unused Holes
- 32 13/16"
( Total 227 Percent of Supports With Holes Larger Than the Indicated Size "Best" (50% confidence) 95% Confidence Estimate Estimate i
Anchor Holes Larger Than 1-11/16" 0.31% 1.32%
Members Holes Larger Than 29/32" 0.31% 1.32%
l i
I
- Only one of the 32 supports with unused holes was found to contain a hole larger than the allowed 3/4" size (i.e. 1/16" more than 3/4").
. . . _ 1_ . . .,_ . . . _ - - . - - . . - - - - - - - - -
l Rcvision: 1 Page 37 of 57 fh t ) RESULTS REPORT LJ ISAP V.d (Cont'd)
FIGURE 1. UNUSED HOLE CRITERIA FOR CABLE TRAY SUPPORTS
- 1. All unused holes greater than 3/4-inch diameter shall be repaired.
- 2. Unused holes which are spaced 2 inches or less (measured center to center) from a used or unused hole shall be repaired.
- 3. No two holes (used or unused) snall be located in the same cross-sectional plane (see typical examples of acceptable and rejectable bolt / hole configurations).
In summary, when a used hole and an unused hole are in the same cross-sectional plane, the unused hole shall be repaired.
Conversely, when two (2) unused holes are in the same cross-sectional plane, one must be repaired. A cross-section is a section normal to the longitudinal axis of the member.
LCNGITUDINAL &IIS
&l / a
" N r .
l rL& NOES
%J 5 l 5 i ,% >
&l CACSS SECTICNAL ALANE NCRMAL SAM 8LE STAUC? URAL SMapt (O=eneel wees f or eneocle. SECT:CN &-a eco11:eele ese any saecel M".fC7
- ACCExF7 **
t t t ? me er ammas w e' 5uA-eLa~ en $ $%L
,5 1 6 6 :
I I I I l
6 i i i f f f f f W .ne s e > *' M .am,s en k
-) b. - **6f ) . II ~ )
i i i i
- Holes or bolts are in the same cross-sectional plane.
- Holes or bolts not in the same cross-sectional plan. must also meet the distance criteria (greater than 2 inches) and hole O size criteria (less than or equal to 3/4-inch diameter).
O A _ __