ML20245F325
| ML20245F325 | |
| Person / Time | |
|---|---|
| Site: | Comanche Peak  |
| Issue date: | 04/24/1989 |
| From: | William Cahill TEXAS UTILITIES ELECTRIC CO. (TU ELECTRIC) |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| TXX-89209, NUDOCS 8905020341 | |
| Download: ML20245F325 (10) | |
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M llllllll" ':lllllll Log # TXX-89209 L
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Ref. # IR 89-06
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IR 89-12 1UELECTRIC April 24, 1989 W. J. Cahm Executwr Vice President U. F, Nuclear Regulatory Commission Attn: Document Control Desk Washington, D. C. 20555
SUBJECT:
COMANCHE PEAK STEAM ELECTRIC STATION DOCKET NOS. 50-445 AND 50-446 RESPONSE TO NRC INSPECTION REPORT NOS. 50-445/89-12; 50-446/89-12 AND NOS. 50-445/89-06; 50-446/89-06 Gentlemen:
TV Electric has reviewed your. letter dated March 24, 1989, concerning the inspection conducted by Mr. P. Stanish and another NRC consultant during the period February 8 through March 7, 1989. This inspection covered activities authorized by NRC Construction Permits CPPR-126 and CPPR-127 for CPSES Units 1 and 2.
Attached to your letter was a Notice of Violation.
On Harch 16, 1989, in a discussion between Mr. R. F. Warnick of the NRC and Mr. '
C. Hicks of TV Electric, it was agreed that TV Electric's responses to Notice of Violation 445/8906-V-02 and Notice of Violation 445/8912-V-03 would be submitted concurrently.
We hereby respond to the Notices of Violation in the attachments to this letter.
Sincerely, William J.
ahill, Jr.
BSD/bsd - Response to NOV 445/8912-V-01 - Response to NOV 445/8912-V-02 - Response to NOVs c45/8906-V-02 and 445/8912-V-03
(
l c - Mr. R. D. Martin, Region IV Resident Inspectors CPSES (3)
$0gh ph 400 North Olive Street LB 81 Dallas, Texas 75201 L=2-__-____:--_-___-________-_
Attachment I to TXX-89209
' April'24, 1989 Page 1 of. 2 i
NOTICE OF VIOLATION ITEM A (445/8912-V-01)
Criterion III of Appendix B to 10 CFR Part 50, as implemented by Section 3.0, Revision 0 of the TV Electric Quality Assurance Manual, states, in part,
" Measures shall also be established for the selection and review for suitability of applicat. ion of materials, parts, equipment, and processes that 1
are essential to the s2fety-related functions of the structures, systems and components.... "
Paragraph 6.3.c of ECE-5.19, Revision 2 states, in part, "Tte RE (Responsible Engineer) assigned to perform the review of the vendor document chall ensure that the following items are considered as appropriate or applicable: the material, equipment, document, Service, or process is in compliance with CPSES design requirements.... "
Contrary to the above, snubbers were installed with low strength bolting that could have been overstressed if subjected to the maximum allowable de Ign load.
RESPONSE TO NOTICE OF VIOLATION ITEM A (445/8912-V-01)
TV Electric agrees with the alleged violation and the requested information follows:
1.
Rea;on for Violation The vendor (NPSI) initially provided two types of snubber assemblies to CPSES during the construction phase. The two types of assemblies were identical except that one utilized low strength bolts for connecting the mechanical arrestor to the transition kit while the other type utilized high strength bolts.
NPSI did not indicate that two different types of snubber assemblies had been provided and transmitted Certified Design Report Summaries (CDRSS) based c,. the use of low strength bolts.
CDRSs contain rated load data and are used to determine the proper size j
assembly for a particular application.
Subsequently, NPSI discontinued supplying low strength bolt assemblies and transmitted new CDRSs based on the use of high strength bolts. The NPSI transmittal letter did not indicate a change in bolt strength as a reason for the new CDRSs and stai. ed that the new CDRSs were applicable to all items furnished to CFM S.
NPSI overlooked the fact that' CPSES had previously been supplied low strength bolt assemblies. The erroneous information provided by NPSI resulted in the misapplication of low strength bolt assemblies by CPSES engineering personnel.
' Attachment I to TXX-89209 April 24,.1989 Page 2 of 2 2.
Corrective Steos Taken and Results Achieved Deficiency Report C-88-01197 was written to document that low strength bolt assemblies had been installed based on CDRSs for.high strength assemblies. An evaluation was performed that showed that low strength bolts in size 3 and size 10 assemblies could be overstressed if the i
assemblies were loaded to the rated load for high strength bolt assemblies.
The other size assemblies that contained low strength bolts were found to be capable of withstanding the rated load for high strength bolt assemblies without exceeding ASME code allowable stresses. The evaluation also determined that although the low strength bolts in size 3 and 10 assemblies could be overstressed when compared to ASME code criteria, their loading would be well below the bolts ultimate capacity and the snubbers would have performed their intended function during a safe shutdown earthquake.
Although the evaluation showed that only bolts in size 3 and 10 snubber assemblies had the potential to exceed ASME code allowable stress, a Design Change Authorization (DCA) was issued to require that all sizes of NPSI mechanical snubbers utilize high strength bolts between the arrestor and transition kit.
Based on this DCA low strength bolts are being replaced with high strength bolts in the affected snubbers.
3.
Corrective Steos Which Will Be Taken to Avoid Further Violation'
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NPSI has been made aware of its error and has transmitted appropriate documentation to correct the error.
As an added precaution TU Electric has taken the following actions:
1)
A change has been issued to inspection procedure AQP 11.3 which i
requires QC inspectors to verify that only high strength bolts are used in the connection between the' arrestor and the transition kit for NPSI snubber assemblies.
2)
A DCA was issued to the specification which contains the technical requirements for suppliers of safety related supports and snubbers.
The DCA requires the seller to specifically address the effects of changes to previously supplied material when CDRS, load data sheets, or other design data are submitted.
4.
Date When Fuil Compliance Will Be Achieved The majority of NPSI snubbers that originally utilized low strength bolts l
have had the bolts replaced with high strength bolts. Approximately 30 snubbers are still awaiting bolt replacement.
The completion of bolt replacement is expected to occur no later than June 15, 1989.
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1 to TXX-89209 April'24, 1989 Page 1 of 4 1
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l NOTICE OF VIOLATION ITEM B (445/8912-V-02)
Criterion III of 10 CFR 50, Appendix B, as implemented by Section 3 of the TU Electric Quality Assurance Manual (QAM), states, in part, "... design control measures shall provide for verifying or checking the adequacy of design, such j
as by the performance of design *eviews, by the use of alternate or simplified calculational methods, or by the performance of a suitable testing program Contrary to the above, the NRC inspector identified the following examples of inadequate review of design calculations:
1.
Piping calculation GENX-315, Revision 0, and Calculation Change Notice (CCN) No. I to this revision of the calculation were found by the NRC to contain numerous examples (such as not utilizing proper stress intensification factors for piping thickness less than 3/16 inch and not performing a functionality check using the proper wall thickness) of the reviewer's failure to identify that the preparer did not follow the analysis procedure outlined in the body of the calculation.
2.
The following pipe support calculations were also found by the NRC to contain errors that were not identified by the reviewer:
a.
CT-1-137-714-S22R - Forces and moments transposed incorrectly.
b.
H-SW-1-SB-019-017 Three different instances of incorrect moments.
c.
H-CC-1-SB-046B-Oll Computer model incorrect.
d.
CC-1-068-028-A33R - One weld calculation incorrect.
Wrong weld l
configuration used in another weld calculation.
l e.
CS-1-SB-053A-001 Out-of-plane forces not evaluated.
Local effects not evaluated, f.
SI-1-093-Oll-S42R - Local stress evaluation incoreet. Web crippling not evaluated. Computer model nonconservative.
g.
SI-1-SB-024-007 Computer model incorrect.
h.
CC-1-146-013-S43R - Construction tolerance not considered in the worst case.
"Z" load incorrect.
Slenderness ratio incorrect.
i.
CS-1-906-032-S42K - Moment calculation incorrect.
J.
CT-1-Oll-005-S22K - Baseplate model incorrect.
i k.
SI-1-039-026-S32R - Weld configuration analyzed does not agree with as-built.
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' Attachment 2 to TXX-89209 j
April 24,. 1989 Page 2 of 4 l
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SI-1-039-042-S4?K - Weld analysis incorrect.
Baseplate model incorrect.
m.
VD-1-049-017-S45R - Weld analysis incomplete.
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SI-1-095-003-S42R - Baseplate model incorrect.
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MS-1-025-008-S75K - Construction tolerance not factored into analysis.
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CT-1-008-004-S22R - Loads due to offsets not considered.
Baseplate model incorrect.
q.
CS-X-AB-014-001 Weld analysis incorrect.
Baseplate model incorrect.
r.
CC-X-079-005-A43K - Local stress evaluation incorrect.
s.
SW-1-AB-014-018 Construction tolerance not factored into analysis.
Computer model incorrect.
l RESPONSE TO NOTICE OF VIOLATION ITEM B (445/8912-V-02)
)
TV Electric disagrees with the NRC's finding of a violation of Criterion III l
of 10CFR50, Appendix B, for the following reasons.
As the NRC acknowledges in the March 24, 1989 letter forwarding the Notice of Violation (N0V), TV Electric, at the exit meeting on March 7, 1989, expressed disagreement with the NRC position tnat the errors detected in the Stone and i
Webster Engineering (SWEC) calculations for piping and pipe supports constitute a violation of Criterion III. The NRC's position is that implicit in Criterion III's requirement to establish design control measures for verifying or checking the adequacy of design is that such measures "be effective in identifying errors in the design." The NRC states its opinion that, based on the rate of errors it identifiea, "the implementation of the governing procedures for design control was inadequate." It concludes that, although a citation could have been against either Criterion III or Criterion V, "a citation against Criterion III is appropriate."
TV Electric agrees that, to satisfy Criterion III, design control measures for verifying or checking the adequacy of design must be shown to be effective in identifying discrepancies in the design. However, it is our belief that the test for effectiveness of the verification and checking measures is whether discrepancies that are not detected by those measures are stfcty significant, such that the licensed design or hardware is found to be inadequate.
As we show below, ne such errors have been identified in our evaluation of this NOV.
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. Attachment 2 to TXX-89209 4
I April 24,1989 Page 3 of 4 i
In response to NRC inspector concerns regarding the quality of SWEC l
calculations, TV Electric initiated a management review to assess the adequacy of the SWEC program for preparation and review of pipe stress and pipe support calculations. The results of this review have been detailed in TV Electric-CPSES Engineering Report ER-CS-007 which is available for the NRC Inspector's review. As detailed in ER-CS-007 the following conclusions were reached.
1.
The SWEC program, as defined by its procedures, adequately incorporated
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the pertinent requirements of the applicable codes and standards (10 CFR 1
50 Appendix B and ANSI N45.2.11), and is in accordance with Quality Assurance Topical Report SWSQAP l-74A which was found acceptable by the NRC.
Further, the training for calculation preparers and reviewers was i
found to be sufficiently thorough and provides emphasis on the importance of the individual's work and the need for a quality product.
2.
The overview provided by various programs (Vendor Compliance, Technical Audit Program, SWEC Engineering Assurance, and the Engineering Functional Evaluation) adequately assessed the acceptability of SWEC pipe stress and pipe support calculations.
Where discrepancies were identified by these programs (which have been similar to those identified by the NRC inspector), adequate corrective actions were taken.
These overview programs have not found indications that the SWEC pipe stress and pipe support calculation program is inadequate in that there is no evidence of inadequate design.
3.
The discrepancies identified in the NOV and those identified by the overview programs described above were found not to be safety significant.
l None of the discrepancies impacted design adequacy nor did they result in violations of ASME Code allowable stresses.
Consequently, correction of the discrepancies did not require any design changes or hardware modifications.
TV Electric considers that the above conclusions substantiate its position that the SWEC program for preparation and review of pipe stress and pipe support calculations satisfies the requirements of 10 CFR 50 Appendix B, Criterion III.
The discrepancies identified by NRC were in part instances where some prepar ers did not follow precisely the methodology reflected in the CPPP-7 design procedures.
In a number of instances simplified or alternative analytical methods were utilized by the preparers.
In other instances, the discrepancies resulted from omissions or oversights attributable to human error, e.g., incorrect data transpositions, computational discrepancies.
It appears that these discrepancies were not detected in the design review process in part because of the reviewers' focus on overall acceptability of calculation results and in part because of a lack of sufficient attention to detail and documentation.
1 1
' Attachment 2 to TXX-89209 April 24, 1989 Page 4 of 4 Although TV Electric considers the SWEC program for preparation and review of pipe stress and pipe support calculations to be adequt.f e, we nevertheless wish to minimize discrepancies of the type identified by the NRC. Accordingly, consistent with our policy of continually striving for excellence, TV Electric has directed SWEC to institute the following program enhancements, for not i
only the Pipe Support Engineering discipline but also for the Electrical, Mechanical, Civil / Structural, and Instrument and Control disciplines within SWEC's scope of Corrective Action Prograa activities.
These enhancements, as detailed in report ER-CS-007, are focused on three principal functions which control the quality of the calculations.
These functions are (1) preparation of the calculations, (2) review of the calculations, and (3) supervision of the individuals who prepare and review calculations.
Enhancements addressing these three functions hre summarized as follows:
1.
Additional training for calculation preparers has been instituted to further emphasize the preparers' responsibilities, provide examples of discrepancies that have occurred, and reemphasize SWEC and TV Electric management expectations regarding calculations.
2.
Additional training for calculation reviewers has been similarly instituted and additional requirements for documenting the depth of review have been imposed.
3.
Additional training for supervisory personnel has been instituted which emphasizes supervisory responsibility in the development and review of calculations.
4.
A program for monitoring the effectiveness of the above enhancements has been implemented. The program utilizes calculation reviews by lead engineers as input for CEC 0 QA trending and overall assessment.
The monitoring program will continue until management personnel are assured that the enhancements have been effective.
The actions for Items 1, 2, and 3 were completed by February 24, 1989.
The Item 4 monitoring program is continuing.
The actions taken at CPSES, as described above, have corrected the specific calculation discrepancies identified by the NRC and, through the enhancement of performance of preparers, reviewers and supervisors, provide additional asserance that the occurrence of such undetected discrepancies will be minimized. TU Electric considers that these actiou effectively resolve the concerns cited in the NOV.
Attac' ment 3.to TXX-89209 h
April 24, 1989 Page 1.of 3 NOTICE OF VIOLATION (445/8906-V-02)
Criterion V of Appendix B to 10 CFR 50, which is implemented by Section 5.0, Revision 0, of the TV Electric Quality Assurance Manual (QAM), states
" Activities affecting quality shall be prescribed by documented instructions, procedures, or drawings, of a type appropriate to the circumstances and shall be accompli.shed in accordance with these instructions, procedures, or drawinns." ASME Quality Procedure (AQP)
.3, Attachment 7.2c, paragraph 8.c, requires that U-bolt clearance around the pipe shall not be less than 1/32 inch for pipe support CS-1-AB-238-010-2.
Contrary to the above, unauthorized work or inadequate inspection by QC has resulted in a pipe support (CS-1-AB-238-010-2) deviating from design documentation requirements. Item 4, a U-bolt, does not have the required minimum pipe clearance and the jam nuts are loose.
4 NOTICE OF VIOLATION (445/8912-V-03)
Criterion V of Appendix B to 10 CFR 50, as implemented by Section 5.0, Revision 0 of the TV Electric Quality Assurance Manual (QAM), states, in part,
" Activities affecting quality shall be prescribed by d,cumented instructions, procedures, or be accomplished in accordance with these instructions, procedures, or drawings. Instructions, procedures, or drawings shall include appropriate quantitative or qualitative acceptance criteria for determining that important activities have been satisfactorily accomplished."
The requirements for inspections of component supports, which include pipe supports, are contained in Brown & Root ASME Quality Procedure AQP-11.3.
t Contrary to the above, the NRC inspector identified the following examples of inadequate inspection of pipe supports:
(1) MS-1-003-001-C72S - The beam attachment had one ear that was bent.
(2)
FW-1-018-718-C72K - The snubber clamp on this support does not provide the necessary clearance to allow for the full range of angular motion.
1 (3) CT-i-038-418-C62S - The spring load column is cocked beyond the tolerance of ASTM-A-125.
(4) CS-1-002-700-C52S - No sight hole in one of the spring load couplings.
(5) CC-1-258-003-C53R - The spherical bearing in the sway strut paddle end is partially dislodged.
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(6) RC-1-135-004-C51K - The clamp for this snubber will not allow the full range of angular movement.
L
,. to TXX-89209 Apr.il 24', 1989 Page 2 of 3 (7) CC-1-207-020-C53R - The space between the ears of the clamp exceeds maximum tolerance.
(8)
FW-1-096-002-062K - Inadequate clearance between the clamp and snubber body to allow the full range of angular movement.
l (9)
FW-1-096-002-C62R - Space between the ears of the clamp exceeds the maximum tolerance.
(10) MS-1-340-001-C52S - They eye nut is bound against the top of the pipe clamp.
(11) CC-1-269-700-C53A - One of the welds has a fit-up gap that exceeds the criteria of the weld procedure specification.
(12) MS-1-344-700-C52K - The spherical bearing on the paddle end of the l
snubber is completely dislodged.
l (13) RC-1-018-038-C51K - The space between the ears of the clamp exceeds the maximum tolerance.
(14) FW-1-098-701-C62K - The Jam nuts on both sway strut bodies are loose.
-(15) MS-1-RB019-005 The clamp ears are bent to less than the minimum l
}
allowable dimension.
'(16) CT-1-014-001-S22S - The threaded rod on this support interferes with the supporting steel.
(17) SI-1-070-006-S22R - The ears on the cotter pin are not spread.
(18) BR-X-106-064-S43R - Baseplate not grouted properly.
(19) CS-1-908-702-542R - Jam nut for the sway strut body not tightened properly.
(20) SI-1-060-006-S42R - Clamp ears not parallel and load pin not parallel to clamp bolt.
(21) CS-1-106-717-C42R - Cotter pin missing.
(22) CS-1-106-723-C42R - Cotter pin missing.
(23) CC-1-016-700-A43R - Cotter pin ears not spread (previous inspection finding 445-8865-0-01).
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l to TXX-89209 Apr.il 24, 1989 Page 3 of 3 RESPONSE TO NOTICES OF VIOLATION (445/8906-V-02 AND 446/8912-V-03)
TV Electric agrees with the alleged violations and the requested information is as follows:
1.
Beason for Vio13 tion During the NRC monthly exit conducted at CPSES on March 7, 1989, the NRC notified TU Electric that a Notice of Violation (NOV) would be issued relating to pipe supoort hardware discrepancies, attributed by the NRC to inadequate inspections.
Subsequent to this exit, TV Electric nianagement directed that an engineering walkdown and review of pipe support installations be conducted immediately. The walkdown began on March 10, 1989 utilizing skilled and experienced pipe support engineering and construction personnel. The walkdown was conducted on a roor/ area basis. Walown personnel reviewed accessible pipe supports and noted any unusual condition relating to pipe support hardware, installation or function, as observations for further evaluation. These walkdown activities were completed on March 13, 1989.
Engineering evaluation of the observations from the walkdown is in progress.
The examples identified by the NRC inspector in NOV 445/8912-V-03 as well as the condition described in NOV 445/8906-V-02 relating to pipe support U-bolt clearance and loose jum nuts, and the above pipe support observations have been documt 1 by Corrective Action Request (CAR)89-004.
The CAR program req:.es identification of the cause of the condition, corrective action and action to preclude recurrence. The reason for these violations and observations will be established in the development for the resolution for CAR 89-004.
2.
Correctiva Steos Taken.and Results Achieved As noted above, to address the preliminary results of the engineering walkdown conducted to evaluate the extent of the conditicns described at the March 7,1989, NRC exit meeting and the examples documented in tFis NOV, CAR 89-004 was initiated on April 2, 1989. Noncompliance identified through the implementation of the action plan developed to resolve this CAR will be documented in accordance with the project procedure.
3.
Corrective Steps Which dill Be Taken to Avoid Further Violations The action plan developed to resolve CAR 89-004 will describe appropriate measures to prevent further violations.
4.
Date When Full Comoliance Will Be Achieved Corrective actions for CAR 89-004 are currently being developed. An update to this Response will be submitted providing additional actions planned and the dates for completion of those actions.
The updated response will be submitted no later than May 12, 1989.
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