IR 05000445/1989066
| ML20248A586 | |
| Person / Time | |
|---|---|
| Site: | Comanche Peak  |
| Issue date: | 09/26/1989 |
| From: | Livermore H Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20248A507 | List: |
| References | |
| 50-445-89-66, 50-446-89-66, NUDOCS 8910020252 | |
| Download: ML20248A586 (18) | |
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s - - , x; - > . , ' . , i > APPENDIX B U. S. NUCLEAR REGULATORY COMMISSION ' OFFICE OF NUCLEAR REACTOR. REGULATIONS NRC Inspection Report: 50-445/89-66, Permit's:lCPPR-126 50-446/89-66 CPPR-127 Dockets: 50-445 Construction Permit' 50-446, Expiration Dates: ' Unit 1: August l', 1991 Unit 2: August 1, 1992 Applicant: TU Electr.ic
- Skyway Tower 1400 North Olive Street
~ Lock Box'81 Dallas,_ Texas .75201-Facility Name': Comanche Peak Steam Electric Station (CPSES), Units 1 & 2 Inspection-At: Comanche Peak Site, Glen Rose, Texas.
Inspection Conducted: August 2 through September 5, 1989 ~ ' Inspection conducted"by NRC consultants: W.'P.
Chen - Parameter (paragraphs 2.b and 3.h) P. Stanish - Parameter (paragraphs 2.a, 2.c, 2.d, L 2.e, 2.f, 3.a, 3.b, 3.c, 3.d,.3.e, 3.f, and 3.g) Reviewed by: h ut R i %- 9 H.- H.' Livermore, Lead Senior ' Inspector Date-L I .. 002O252 e9093g g ADOCK 05000445 PDC - \\ _____-_ - _ ___________ __________ - ______ - -__ _ _____ _ _
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) Inspection Summary: Inspection Conducted: August 2 through September 5, 1989 (Report 50-445/89-66; 50-446/89-66) Areas Inspected: Unannounced, resident safety inspection of follow-up on violations / deviations; applicant action on 10 CFR 50.55(e) Construction Deficiencies; and general plant area tours.
Results: Within the areas inspected, a significant weakness was identified in the applicant's evaluation of structural tubing deficiencies.
One violation for failure to take adequate corrective action'(paragraph 3.f) was identified.
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3 DETAILS 1.
Persons Contacted
- J.
L. Barker, Manager, ISEG, TU Electric
- D.JP.
Barry, Director, CECO '*J.
W.
Beck, Vice President, Nuclear Engineering, TU Electric
- 0. Bhatty, Issue Interface Coordinator, TU Electric
- M.
R. Blevins, Manager of Nuclear Operations Support, TU Electric
- H.
D. Bruner, Senior Vice President, TU Electric
- W.
J. Cahill, Executive Vice President, Nuclear, TU Electric
- H.
M. Carmichael, Senior QA Program Manager, CECO
- J.
T.
Conly, APE-Licensing, SWEC
- W.
G.
Counsil, Vice Chairman, Nuclear, TU Electric
- C.
G.
Creamer, Instrumentation & Control (I&C) Engineering Manager, TU Electric
- B.
S. Dacko, Licensing Engineer, TU Electric
- R.
J. Daly, Manager, Startup, TU Electric '
- D.
E. Deviney, Deputy Director, Quality Assurance (QA), TU Electric
- S.
L. Ellis, Performance and Test Manager, TU Electric
- J.
C.
Finneran, Jr., Manager, Civil Engineering, TU Electric
- C.
A. Fonseca, Deputy Director, CECO
- J.
L. French, Independent Advisory Group
- B.
P. Garde, Attorney, CASE
- J.
Greene, Site Licensing, TU Electric
- W.
G. Guldemond, Manager of Site Licensing, TU Electric
- T.
L. Heatherly,. Licensing Compliance Engineer, TU Electric
- J. C. Hicks, Licensing Compliance Manager, TU Electric
- C.
B. Hogg, Chief Engineer, TU Electric
- D.
L. Hubbard, Technical Training Manager, TU Electric
- A.
Husain, Director, Reactor Engineering, TU Electric
- J.
J. Kelley, Manager, Plant Operations, TU Electric
- J.
E. Krechting, Director of Technical Interface, TU Electric
- D. M. McAfee, Manager, QA, TU Electric
- S.
G. McBee, NRC Interface, TU Electric
- J.
W. Muffett, Manager of Engineering, TU Electric
- E.
F. Ottney, Program Manager, CASE
- S.
S. Palmer, Project Manager, TU Electric
- P. Raysircar, Deputy Director / Senior Engineering Manager, CECO
- J.
D. Redding, Executive Assistant, TU Electric
- D. N. Reynerson, Director of Construction, TU Electric
- M. J. Riggs, Plant Evaluation Manager, Operations, TU Electric
- A.
B. Scott, Vice President, Nuclear Operations, TU Electric
- R. L. Spence, TU/QA Senior Advisor, TU Electric
- J.
F. Streeter, Director, QA, TU Electric
- C.
L. Terry, Unit 1 Project Manager, TU Electric
- 0.
L. Thero, QTC Consultant to CASE
- T. G. Tyler, Director of Management Services, TU Electric l
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- R.
G. Withrow, EA Manager, TU Electric The NRC inspectors also interviewed other applicant employees during this inspection period.
- Denotes personnel present at the September 5, 1989, exit meeting.
2.
Follow-up on Violations / Deviations (92702) a.
(Closed) Violation (445/8426-V-02): This violation was related to various pipe support and cable tray hanger deficiencies.
NRC review of the specific actions taken-in response to this violation was documented in NRC Inspection Report 50-445/89-12; 50-446/89-12.
In that report, closure of the violation was deferred until the applicant fully addressed the findings of a similar violation issued in the above' mentioned report (445/8912-V-03).
The referenced violation documented twenty-three examples of similar inspection program deficiencies and closure of this violation is contained in NRC Inspection Report 50-445/89-54; 50-446/89-54.
Therefore, based on NRC inspection of the recent applicant actions in this area and past reviews by the NRC as documented in the above inspection reports, this violation is closed.
b.
(Closed) Violation (445/8514-V-03): During ERC's reinspecti&1 of skewed welds in Unit 1, undersized conditions were identified on Brown & Root (B&R) nonconformance reports (NCRs).
CPSES Station Administration Manual Procedure STA-405 required that all documented nonconformances in which "use-as-is" dispositions were recommended be forwarded to TU Operations Results Engineering Group for review to determine if as-built documentation changes were required.
Further, CPSES Nuclear Operations Engineering Manual Instruction NOE-201-5 required that proposed drawing changes be submitted to operations for review, approval, and authorization to distribute the revised drawing.
The NCRs associated with the undersized skewed welds were identified as XI-2, -3, -4, -5, -6, -7, -8, -10, and -11.
The applicable pipe support drawings were revised by TU Nuclear Engineering (TNE) to reflect the as-built weld configuration.
Recalculations were performed to support i
the use of these without rework or repairs.
While the NCRs were not formally dispositioned, this action, in effect, provided a "use-as-is" disposition.
TU operations did not review and approve the drawing t- .. _. _ _ _ - _ _ _ _ _ _ _ - _ - _ _ _ _ _ - _ _ _ _ _ _ _ _ -
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J revisions as required, and TU. Operations did not initiate their'own NCR(s) to address these conditions until after J.
TNE had revised and distributed the drawings.
l l II The applicant determined that.the reason for the violation was that engineering procedures were not-issued prior to implementing' tasks associated with Operations ! review, approval, and authorization of release of: ) ' drawings for systems under Operations custody.
As j corrective. action, TNE-AD-4-5, Revision 0, " Control of l Unit 1 Pipe. Support Drawings," was issued .This ~ procedure established guidelines for administrative control of pipe support drawings by Pipe Support Engineering (PSE).
Revision 1-of this procedure was subsequently issued to further clarify the responsibility of Operations and PSE concerning drawing change approval i and release.
Also, Deficiency Report (DR)-85-167 was
. initiated-for failure of Engineering to follow-i procedures.
This DR was closed based on Revision 1 of
TNE-AD-4-5.
The NCRs referenced above were converted to operations NCRs and closed based on the "use-as-is" .j dispositions.
i To prevent recurrence of this situation, custody of l Unit 1 and Common pipe supports was returned to
Engineering and Construction.
The NRC inspector reviewed the specific NCRs.and l calculations performed on the skewed welds in. question j and th: procedures referenced above and concurs that the actions are appropriate and fully address and resolve
! this issue.
This violation is closed.
c.
(Closed) Violation (445/8519-V-03): FRC Inspection j-Report 50-445/85-19 covers inspections performed by NRC
Nuclear Reactor Regulation (NRR) personnel during the j period of November 18 through December 18, 1985.
The ' deficiencies identified were concerned with cable trays and cable tray supports, deviations from drawings, and changes to supports not being adequately controlled or i documented.
These concerns were also documented as part
' of Enforcement Action 86-09 in Appendices B.I.A and B.II.
. NRC review of applicant's action in response to the Enforcement Action is documented in NRC Inspect 3nr Reports 50-445/89-20; 50-446/89-20 and 50-44%'t8-65; i 50-446/88-61.
I Based on the applicant's action as documented in the i I above inspection reports, this violation is closed.
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(Closed) Violation (445/8735-V-02): While performing inspections of the applicant's as-built program for
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. Train A and B conduit and heating, ventilating, and air-conditioning (HVAC), the NRC inspector identified'the following1 conditions that were not properly documented by the walkdcwn personnel: . ' (1) On. conduit, support C13G04860-02,. there was no washer installed >under one of the hex. nuts for a'Hilti Kwik Bolt (HKB) and this was not documented on an NCR as required.by the Field Verification Method (FVM).
, - (2)'_On conduit support C14G20243-01,' the length of the baseplate:was reported' incorrectly.
(3) On conduit support C14G11447-03, several dimensions " reported were incorrect by more than the tolerance allowed by the'FVM.
M '(4) On conduit support C14G11447-04, one dimension locating a unistrut outrigger was incorrect.
(5) On conduit support C14G11447-14, the number of HKBs reported was incorrect.
The existence of one HKB was not reported.
(6). A fillet weld 3/16" x 5/8" long on seismic duct hanger DH-1-844-1K-4F was incorrectly identified.
(7) Five finished welds located on seismic duct hanger DH-1-844-1K-WP13 and portions of three welds on DH-1-844-1K-1R did not have the required galvanized coating.- (8) Corrections were made to figure 7.6 of Construction Procedure CHV-106, Revision 1, without performing a formal revision to the procedure.
The applicant agreed with the violation and stated that the reason for Items (1) through (5) of the violation were the result of errors on the part of walkdown personnel.
For Item (6), they stated that the , documentation error was the result of the walkdown engineer making a conservative assumption of identifying ' the weld in question as a tack weld knowing that no credit for strength is taken for tack welds during structural analysis.
Item (7) occurred because craft workers misinterpreted a note concerning inspection requirements on the associated drawings in addition to the QC inspector failing to note the inadequate coating.
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Item (8) resulted from errors on the part of the personnel initiating the change.
These changes were promulgated via memo rather than a formal procedure change as required by ECE 1.04.
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7 The corrective actions taken for Items (1) through
(5) included correcting the discrepant walkdown forms in accordance with DR C-88-Oll76 which was initiated to document the incorrect documentation.
NCR 87-04505 was generated to document and correct the missing washer on conduit support C13G04860-02.
Also, analysis was performed to ensure that none of the conduit support discrepancies affected the structural adequacy of the supports in question.
< For Item-(6), Revision 6, to CPE-EB-FVM-CS-029 was issued to allow welds longer than 1/2 inch to be called tacx welds.
Based on this revision, no change to the walkdown data stunt was required.
For Item (7), NCRs 87-04198 and 88-00962 were written to document the discrepancies on duct hangers DH-1-844-1K-WP13 and DH-1-844-lK-lR.
For Item (8), DR C-87-0593 was issued to document the improperly controlled procedure change and Revision 2 of the procedure was issued to formally change figure 7.6.
For preventative action, conduit walkdown personnel were ' retrained on the importance of documenting walkdown data completely and accurately.
Further, Ebasco determined that changes to.walkdown procedures should reduce the occurrence of some types of errors; therefore, procedures were revised to minimize the need for walkdown engineers to measure to hypothetical lines such as conduit centerlines.- Also, to assess the generic implications of walkdown discrepancies, Ebasco selected samples of completed walkdown data and re-examined the attributes in these samples.
The results of this review and NRC review of these results are discussed in NRC Inspection Report 50-445/88-05; 50-446/88-04.
The NRC inspector-also reviewed Revision 3 to CPE-EB-FVM-CS-033 which changed the locations to which dimensions should be measured from centerlines to accessible edges of clamps, structural steel, etc.; plus the revisions to CPE-EB-FVM-CS-029, MS-85, Appendix K,
ECC 1.04 and CHV-106 for resolution of the HVAC aspects of this violation.
The NRC inspector also reviewed the NCRs and DRs generated to address the specific items and performed inspections to ensure that the necessary rework had been completed., Based on the above actions, this violation is close _ _ _ _ _ _ _ _ _ _ _ _ _ r . . ,, - - ' .
c.
(Closed) Violation (445/8871-V-03): During a plant tour of Unit 1 and Ccmmon areas the NRC inspector observed a sway' strut on support SW-1-132-039-A43R that had very little clearance in the clamp forward paddle connection.
This condition would restrict the amount of angular rotation to that below the vendor specified minimum, During operation,.this could cause the transfer of forces and moments into the piping system and support structural members that had not been considered in-the original analysis of these items.
The concern expressed in this violation has been fully , encompassed by the actions taken by the applicant in response to the Notice of Violation (NOV) 445/8912-V-03.
NRC review of the actions in response to this NOV are documented in NRC Inspection Report 50-445/89-54; 50-446/89-54.
Based on the above,.this violation is closed.
f.
(Closed) Violation (445/8912-V-02): During NRC review of Stone and Webster. Engineering Corporation (SWEC) design calculations, the NRC inspector identified numerous examples of inadequate review of piping and pipe support design documentation.
TU Electric in letter TXX-89209 disagreed with this citation because, based on their review of the examples cited by the NRC inspector and other similar examples identified by various other programs such as: Vendor Compliance, Technical Audit Program, SWEC Engineering Assurance, and Engineering Functional Evaluation, no identified error in SWEC's design calculations had resulted in the identification of a safety significant defect.
Regardless of the number of errors, if no single error was safety significant by analysis, then there was no problem with'their review process.
We might add that this philosophy was shared by TU Electric QA.
In their opinion, this is the critical test of the adequacy of their design control program.
l I However, regardless of their disagreement in an effort to l minimize discrepancies of the type identified by the NRC inspector, TU Electric directed SWEC to institute the following program enhancements for the Electrical, Mechanical, Civil / Structural, and Instrumentation and Control disciplines within SWEC's scope of the Corrective Action Program (CAP) as well as the Piping and Pipe Support Engineering group: (1) Additional training for calculation preparers was given to further emphasize the preparer's responsibility and reemphasize SWEC and TU Electric management's expectations regarding calculations.
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.(2) Additional training for calculation reviewers was given and additional requirements for documenting ) the depth of review were imposed.
(3) Additional training for supervisory personnel was i 'l performed which emphasized supervisory responsibility in the development and review of calculations.
(4) A program for monitoring the effectiveness of the above enhancements was also implemented. 'This program utilizes calculation reviews by lead engineers as input for CECO QA~ trending and overall assessment.
Also, the specific discrepancies identified by the NRC inspector have been corrected.
The NRC inspector attended. portions of the training performed by SWEC in response to the concerns cited in the NOV.
The.NRC inspector found this training to be effective in that it stressed the types of errors encountered, stressed responsibilities of the personnel involved, and stressed the methods of documenting the reviews performed.
To assess the effectiveness of the enhancements to the SWEC design control program, the NRC inspector reviewed the following calculations that had been completed subsequent to the implementation of this program: Calculation Number Revision j SI-1-199-703-C41K 1 (CCN 4) ' DD-1-DG-013-017-3 0 (CCN 2) CS-1-259-700-A53K 0 (CCN 2) CC-1-949-704-A73R
SW-1-173-048-S43R 1 (CCN 1) DD-1-016-005-S33R 1 (CCN 1) CS-1-AB-215-001-5 0 (CCN 1) DO-1-038-007-S53K 0 (CCN 1) DO-1-DG-044-015-5 1 (CCN 2) CC-1-162-717-A43R 0 (CCN 1) CCN = Calculation Change Notice The NRC inspector's review of the above calculations, while there were some minor errors detected, revealed that the overall quality of the calculations was considerably better than the examples cited in the NOV.
Based on these reviews, the NRC inspector feels that the actions taken by the applicant have resulted in a more - _ _ _ _ _ - _ - _ _ - _ - _ _ _ _ _ _ _ _ _ _ _ -
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offective design control program.
This violation is closed & 3.
Applicant's Action on 10 CFR 50.55(e) Construction Deficiencies (92700) a.
(Open). Construction Deficiency (SDAR CP-85-50): During an engineering review by the applicant, damaged cable tray tee fittings were.noted in the lay-down area.
In the process of establishing repair procedures, it was observed that welding processes were used in the manufacture of these cable tray fittings which were not in accordance with the supplier's (T.
J.
Cope) drawings.
The cause of this deficiency was determined to be inadequate information provided on the vendor's drawings relative to welding attributes, specifically notes instead of detailed weld symbols were used to provide necessary welding information for the installer and/or fabricator.
l For corrective action, a minimum acceptable weld configuration was established for each tee fitting configuration by Calculation CTH-SPG-99001, Revision 1, " Cable Tray Tee Fitting Welding Evaluation."
The adequacy of the minimum weld configuration was i demonstrated in static testing performed by Corporate Consulting and Development Company (CCL).
Allowable capacities for tee fittings were then based on a combination of original vendor test data,' tray and fitting tests performed by CCL, and the engineering analysis.
The design validation of these tees, based on
the derived allowable capacities, was incorporated into Procedure ECS-5101, Revision 1, " Cable Tray and Cable Tray Hanger Design."
In order to establish that the installed components conformed to the minimum weld configuration criteria, a walkdown was performed using FVM-CS-050, Revision 1, " Field Verification Method T. J.
Cope Flat Ladder Tee Fitting Selected Attributes Data Collection."
All inspected fittings that did not meet minimum acceptance criteria were documented on NCRs and Design Change Authorization (DCAs).
To preclude recurrence of this condition, the applicable vendor drawings were revised specifying weld symbols rather than notes The NRC inspector reviewed generic DCA 41204 issued to define the required weld connection for the tee fittings in question.
This DCA required that 5/8-inch long welds _ _ _ _ _ _ - ______ _ _ -
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! be added to each channel / stringer connection identified as deficient by the walkdowns performed by FVM-CS-050.
The weld size was specified to be equal to or greater-than the thinner part joined.
The NRC inspector also reviewed the applicable FVM which defined the scope of I the inspection to be the T. J.
Cope Ladder Tee Fittings j to obtain fitting dimensions and. weld information.
In addition, this FVM required an evaluation-and record of ' ease of in-situ repair.
Fittings determined to be inaccessible for weld repair in accordance with DCA 41204 were resolved in accordance with DCA 77846, Revision 4.
which required the addition of aircraft' cables eo reinforce the connection in place of the additional welding.
The FVM also required that all deficiencies identified be documented on NCRs.
Test Report CCL-A-742-87 was also reviewed by the NRC inspector along with Test Procedure 1903.40-1 and the summary of results.
In ord3r to complete the NRC review of the Construction Deficinncy, the following additional information is requirid: (1) an explanation of why, as stated above, noncontsrming conditions were documented on DCAs and not on.stansard discrepancy paper, such as NCRc, (2) documentation indicating how vendor test data, CCL test results, and engineering calculations were adapted into the design criteria contained in ECS-5101, and (3) confirmation that all necessary rework has been completed and inspected by QC.
b.
(Closed) Construction Deficiency (SDAR CP-85-52): The NRC identified errors in the " Red Line" drawings being used to as-built cable tray hangers (CTHs) in Unit 1 and Common buildings.
These findings were identified in NRC Inspection Report 50-445/85-19.
TU Electric later substantiated many of the findings and suspended the as-builting efforts.
The cause of the deficiency was identified to be procedural and training inadequacies in the early phases of the CTH as-built inspection program.
Corrective and preventive action included revision'of Procedure TNE-AB-CS-01 to separate the engineering and QC responsibilities, include inspection tolerances, and provide for independent verification.
Further, personnel were trained to these revised procedures.
The results of the early phase of the as-built program were not used.
A 100% validation / inspection of CTHs was resumed in accordance with the revised criteria including those CTHs j which had been inspected in the initial phase of the program.
This program was subsequently incorporated into l - _ _ - _ _ _ _ _ _ _ _ _ _
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the CTH CAP.
Modifications as a result of the CTH CAP j are being tracked by the applicant as part of SDAR CP-85-35; therefore, because the concerns associated with SDAR CP-85-52 are fully addressed by the CTH CAP, closure of-SDAR CP-85-35 will encompass the subject construction i deficiency.
This construction deficiency is closed.
c.
(Open) Construction Deficiency (SDAR CP-87-13): ! Nonconformance Report (NCR) E-86-101601 documented a separation violation between a safety related conduit and a nonsafety-related cable tray.
This separation violation was caused by the removal of the tray cover after QC acceptance without documenting the removal on an Item Removal Notice (IRN).
The procedures in place at the time did not control the removal of Non-Q tray covers or address the subsequent separation violations.
Corrective action for this deficiency included issuing Design Change Authorization (DCA) 25487 against Specification 2323-ES-100 which specified the separation requirements to be utilized in the reverification program that is delineated in CPE-SWEC-FVM-EE-088, which requires two engineering walkdowns to ensure raceway separation.
ECC-2.13-05, which replaced Procedure CP-CPM-6.10, was issued and included a requirement that an IRN be issued to document removal and reassembly of cable tray covers j and other previously completed commodities.
The NRC inspector has reviewed the reference documents and concurs that:the proper procedural controls are in place to preclude repetition of this deficiency.
However, since the corrective actions in response to this deficiency are not complete, closure of this item will be differed until notification of completion of the necessary rework is received from the applicant.
d.
(Closed - for Unit 1 only) Construction Deficiency l (SDAR CP-86-53): While performing design verification for Unit 2 conduit system structural adequacy, a potential deficiency was identified.
The deficiency occurred whenever a conduit changed direction and terminated in an airdrop with no support provided between the change of direction and the airdrop, and a coupling was present prior to the change in direction.
The unsupported portion of the conduit, under seismic excitation, places a torsional movement at the coupling which the threaded coupling cannot resist.
This could result in significant unanticipated movements which would be resisted by the cable inside the conduit.
The cable was not designed to resist these potential loads.
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Testing performed by the applicant concluded that fiber-glass cloth / resin material would adequately resist the anticipated' torsional movements.
Corrective action was to install the fiberglass cloth / resin material or the addition of conduit supports to resist the torsional movements.
The affected conduits were identified by a walkdown to the requirements of CPE-EB-FVM-CS-033 and DCAs were generated for the individual conduits to define the-corrective actions.
The NRC inspector has reviewed the walkdown results and several of the DCAs as well as the construction travelers (cts) and based on this-review concurs that this issue has been adequately addressed.
This construction deficiency is closed for Unit 1 - only.
e.
(Closed - Unit 1 only) Construction Deficiency (SDAR CP-88-21): Design validation indicated that tubing clamps supplied by J.
C. White may have been overtorqued during installation.
Specifically, the minimum torque requirements for setting HKBs and installing attachments to Unistrut channels exceed the maximum torque for J.
C. White Company instrument tubing clamps.
The vendor recommended torque value for their NC-2-375/500-3D three directional restraint assembly is 32-34 inch-pounds.
Two frequently used applications of these clamps are to attach them to either Unistrut using a bolt and spring nut or directly to concrete using a single HK3.
An installation torque of 8 foot-pounds (96 inch-pounds) is required to set a HKB.
The applicant calculated a clamp stress resulting from this torque in excess of 43 KSI.
The allowable stress for the clamp material at 100 degrees is 22.5 KSI.
A similar condition also existed for installations to Unistrut.
These deficiencies were caused by the failure to recognize the individual torque requirements of the various components that make up the restraint assembly.
Failure of the clamp assemblies could have caused damage or failure of safety-related instrument tubing.
As corrective action, a new clamp was developed which meets all installation requirements.
Installation Specification CPES-I-1018 and drawing series 2323-ECE-I-001 were revised to indicate the applicable tube clamps and corresponding torque values required for each application.
Tube clamps requiring replacement were identified during the implementation of the instrument < tubing walkdown performed to CPE-SWEC-FVM-IC-069 and appropriate modifications were made according to approved procedures as they were identified.
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i The NRC inspector reviewed-the applicable sections of Specification CPES-I-1018 which requires that tubing supports / restraints be in accordance with the I-001 series drawings.
These drawings, also reviewed by the NRC inspector, provide details of the proper'(redesigned) clamp and the approved applications of the clamp.
Also provided on the drawings are the installation requirement ' instructions which_ require that.the HKB, Nelson Stud, cap screw, etc., are torqued prior to torquing the " flange bolts."
The NRC inspector also reviewedECalculation-16345-EM(S)-019, Revision 1, " Supplemental Calculation l' for the Load Capacity of Instrument Tubing Support. Type T08.3D & 2D Drawing No. 2323-I-001-T08."
This calculation defined the normal / upset and faulted capacity of the tubing clamps in question for the typical applications provided on the I-001 series drawings.
The NRC review of-this issue also included an evaluation of how FVM-069 addressed this issue.
This FVM requires-that all' tubing supports be in accordance with the I-001 . series drawings or be individually evaluated.
Based on the above reviews, the NRC inspector concurs that this issue has been adequately addressed.
This construction deficiency is closed for Unit 1 only.
f.
(Open) Construction Deficiency (SDAR CP-88-028): During the assembly of a Unit 2 pipe support, a crack on the internal radius of a piece of tube steel (structural tubing) was identified.
Further investigation identified similar defects on tube steel supplied by the same manufacturer and received on the same Receiving Inspection _ Report (RIR).
In addition, the wall thickness of some tube steel appears undersize.
In the applicant's letter TXX-88562, covering the topic of tube steel manufacturing' defects, it was' reported that split seam welds on tube steel in the service water pipe. tunnel had been identified on NCRs; and the scope of this construction deficiency evaluation was increased to address this issue also.
To' assess the corner; crack and thin wall deficiencies, the' applicant performed a metallurgical evaluation to determine'if the steel plate used to manufacture the tubing had been' defective.
Results indicated that the base material met the chemical and physical material properties of the subject specification (ASTM A-500 Grade B).
This fact suggested that the cause of the deficiency was in the manufacturing process.
SWEC's evaluation of these conditions is contained in Report No. 15454-N(C)-020 and states the corner cracks were identified in-4 x 4 x 1/2 inch tube steel furnished by DuBose Steel Inc. and fabricated by UNR/Leavitt.
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the cracked tube steel identified was 4 x 4 x 1/2-inch, was furnished on Purchase Order (P.O.) CPF-13516-S, and was traceable to seven coil numbers which were fabricated during a. June 1986 production run.
Cracking was shown to occur when the manufacturing. process results in nonuniform geometry and sharp inside corner radii.
In an effort to determine the exact cause of the corner cracks, Battelle Memorial Laboratories performed an investigation at the manufacturer's facility.
UNR/Leavitt attempted to purposely induce cracks by forming sharp corners in sample tubing.
Examination of these samples revealed cracks much shallower than those detected in the material received at the site.
However, Battelle concluded that l shallow cracks can be introduced in the forming process and that more comprehensive inspection criteria should be established.
In addition to the Battelle investigation, a field review was performed.
The review consisted of 100 samples selected from all tube steel coils supplied by UNR/Leavitt and all 4 x 4 x 1/2-inch tube steel supplied by other manufacturers, with a sample lot of five samples per size per manufacturer.
The result of this survey showed that the evidence of cracking was present only in-the six identified coils of 4 x 4 x 1/2-inch tubing supplied by UNR/Leavitt and that certain geometric parameters (specifically the ratio of the lengths of opposite sides) indicate a potential for corner cracking.
To mitigate the potential of corner cracking of 4 x 4 x 1/2-inch tubing, additional receipt inspection guidance has been provided to QC which requires engineering evaluation of tubing not meeting the applicable parameters.
These guidelines were added to paragraph 6.5.2.1 of Procedule AQP-ll.4, Revision 2DCN2, " Receiving Inspection."
The supports which utilized the cracked tubing were rework 1d by replacing the subject members.
For the second part of this SDAR, tubing with walls that did not meet specification requirements, it was reported that two sizes of tubing had been identified as having walls thinner than permitted by ASTM A-500.
They were 6 x 6 x 1/2_and 5 x 5 x 1/2-inch tubing.
NCRs were written for 25 pipe supports utilizing this material and were dispositioned as satisfactory based on engineering analysis.
This analysis used either the actual wall thickness of the tubing or the next smaller standard wall thickness.
All required attributes were found to be acceptable by this review.
Therefore, no further corrective action was deemed necessar _ _ _ - _ _ _ _ _ _ - , . ~ ,r "L . . w , .
NRC review of-this part of this construction deficiency or material-nonconformance concludes that for the identified condition:an inadequate technical review hau been accomplished.. The evaluation of this deficient condition. focused on only those supports manufactured from the specific-heats of-material initially identified s and no evaluation was made if other heats manufactured by: this manufacturer, or others, were received with. wall thicknesses below specification' allowable.
Also, no discussion was provided as to why this nonconforming condition was not identified during receiving inspection.
. For the third part of this issue,.the split seam welds on the service water tunnel pipe' support frames, SWEC issued Report,No.15454-N(C)-021.
This report states that the split seams were found in one of the two heats of material of 10 x 6 x 1/2-inch tubing used.as the columns for the frames in the service' water tunnel.
The material with the split scims was manufactured by-WTA; the other heat had been manufactured by Regal Tube.
Further, the report states ultrasonic examination of the columns manufactured.by WTA'". .. reported indications at several locations and lengths of members, in addition to the 2 initial splits. ." The report also' states .. that samples were taken from'the face containing the weld seam and were taken at sufficient distance from the observed split.
These samples were then tested to . determine the effect of the cracks on the material characteristics.
The conclusions drawn were that these cracks would have adversely affected the ability of the supports to perform their' intended function; therefore, [ repairs were undertaken.
L i The cause of the deficiency was determined to be the ' welding sequence associated with modifications being performed when the deficiency was observed.
However, the NRC inspector witnessed liquid penetrant examination of the sample that was taken from the column exhibiting the . split seam.- The NRC inspector was informed that the L reason that the sample was taken a distance from the location of the observed split was to deteamine if the installation process or the manufacturing process had , caused the defect not, as the report stated, to minimize ' the effects of this installation process on the crack depth.
The result of the liquid penetrant examination revealed.that there was'a subsurface defect in the seam J L weld.of the tubing more consistent with a manufacturing defect than an installation induced crack.
The welding of the corner plate associated with the design change being implemented was being performed on the face of the tubing containing the seam weld, this welding, if it were the initial cause of the defect, would have caused ) _ _ _ _ _ - _ _ _ _ _ _ - _ _ _ - _ _ _ _ _ - _ - _ _ - _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
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I surface cracking adjacent to the modification, not I subsurface cracks a distance away from the' split l location.
Therefore, the root cause assessment of this i condition was not accurate; therefore, the corrective actions taken were not sufficient.
If the weld sequence was the cause of the split seam, as - proposed by SWEC, no review for generic applicability has -{ ' been performed outside of the service water tunnel.
For example, how does this type of weld differ from a flare bevel weld in the corner of a structural tubing box frame with the same degree of end restraint? Also, the conclusion that the split seam condition is not reportable is inconsistent with the amount of repair observed by the NRC inspector.
Having to repair more than one hundred and fifty feet of the seam weld can only be deemed excessive, and this item should have been identified as reportable and evaluated for its generic safety implications.
The failure to take adequate corrective action by not-performing a review for the possible generic implications for the split tubing seam welds and the thin-walled tubing discussed above is a violation of Criterion XVI (445/8966-V-01; 446/8966-V-02).
g.
(Open) Construction Deficiency (SDAR Cp-88-042): During maintenance activities on valve 1HV-4514 in the component Cooling Water (CCW) system, a flange misalignment was discovered.
Excessive forces were utilized in the realignment of the piping by utilizing a hydraulic jack to reposition the subject piping contrary to site procedures.
To determine if this condition could have resulted in a safety concern, two separate analytical models were evaluated.
In the first analysis, the piping was modeled as free ended with a force of 27,600 pounds (27.6 kips) applied at the free end.
This addresses the effects of actual conditions experienced during the valve removal and subsequent realignment.
The 27.6 kip force represents the force that was required to realign the piping as measured using a dynamometer.
This analysis proved that the structural integrity of the piping and supports was not compromised.
The second model evaluated the adequacy of the piping and pipe supports by modeling the valve installed and with a force of 27.6 kips applied at the location of the flange adjacent to the valve.
This represents the case if the jacking had taken place and had gone undetected.
This analysis indicated that
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the piping, pipe supports, and valve would have met code allowables.
Therefore, this deficiency would not have caused a safety significant condition.
NRC review of this issue revealed that, in order to prove structural adequacy of the piping system,-in one of the analyses discussed above, allowable stresses used exceeded code allowables.
Specifically, for one of the piping tees, actual yield strength had to be used as an allowable stress because of the high stresses caused by the abnormal event.
Also, the NRC inspector observed that the load calculated for ora of the sway struts supporting the pipe in question exceeded the maximum faulted allowable for this component.
To-resolve this issue, the applicant contacted the vender and, based on the actual installed configuration, the vendor was able to determine that the sway strut in question, because it was shorter than the maximum allowable length, was adequate.
Further, the applicant stated that they felt that the cause of the original misalignment was the welding process used to install an anchor on the system in the vicinity of the valve that was removed for maintenance.
The NRC inspector asked that if this supposition that the welding process was the cause of the misalignment is accepted, what precautions, in light of the high piping stresses and support loads, are being taken to preclude this type of occurrence in the future.
The applicant stated that they would review the situation j ' and determine if further controls on the welding process are appropriate.
This Construction Deficiency will remain open pending the applicant's evaluation and, if required, review of formal procedural changes.
4.
Plant Tours (50090, 52053, 37051) The NRC inspectors made frequent tours of Unit 1, Unit 2, and common areas of the facility to observe items such as housekeeping, equipment protection, and in-process work activities.
No violations or deviations were identified and no items of significance were observed.
5.
Exit Meeting (30703) An exit meeting was conducted September 5, 1989, with the applicant's representatives identified in paragraph 1 of this report.
No written material was provided to the applicant by the inspectors during this reporting period.
The applicant did not identify as proprietary any of the materials provided to or reviewed by the inspectors during this inspection.
During this meeting, the NRC inspectors summarized the scope and findings of the inspection.
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