ML19210D228
| ML19210D228 | |
| Person / Time | |
|---|---|
| Site: | Summer  |
| Issue date: | 11/08/1979 |
| From: | James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| To: | Mary Johnson SOUTH CAROLINA ELECTRIC & GAS CO. |
| References | |
| NUDOCS 7911260151 | |
| Download: ML19210D228 (1) | |
Text
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UNITED STATES NUCLEAR REGULATORY COMMISSION
) *, I' oE REGION li E
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o 101 MARIETTA ST., N.W., SUITE 3100
%/
ATLANTA, GEORGIA 30303 o
NOV 8 1979 In Reply Refer To:
RII:JP0 50-395 South Carolina Electric and Gas Company Attn:
M. C. Johnson, Vice President Special Services and Purchasing Post Office Box 764 Columbia, South Carolina 29218 Gentlemen:
e Enclosed is IE Bulletin No. 79-02, Revision No. 2 which requires action by you with regard to your power reactor facility (ies) with an operating license or a construction permit.
Should you have any questions regarding this Bulletin Revision or the actions required by you, please contact this office.
Sincerely, b
xJaiiies F. 0'Reilly Director
Enclosure:
IE Bulletin No. 79-02, Revision No. 2 w/encls.
1F1 345 7 911260 k h.\\
4 NOV 8 1979 South Carolina Electric and Gas Company cc w/ encl:
T. B. Conners, Jr.
Conners, Moore and Corber 1747 Pennsylvania Avenue, N.W.
Washington, D.C.
20006 A. A. Smith Quality Assurance Post Office Box 8 Jenkinsville, South Carolina 29065
- 0. S. Bradham, Manager
' Nuclear Operations Post Office Box 8 Jenkinsville, South Carolina 29065 17o1 346 e
IE Bulletin No. 79-02 November 8, 1979 Revision 2 Page 2 of 7 also show low cycle dynamic failures at loads below the bolt static capacities due to joint slippage.
In the review of anchor bolt installation practices, three facilities (Trojan, R2 Duane Arnold, and Zimmer) have been identified which use expansion anchor bolts R2 in concrete block walls to attach Seismic Category I piping supports. Testing R2 results of anchor bolts in concrete block walls performed at FFTF indicate signi-R2 ficantly lower ultimate capacities than for those in concrete. An Information R2 Notice will be issued which provides additional details on the deficiencies R2 identified at Trojan.
R2 In the review of responses to the Bulletin, we have become aware that licensees R2 may not have included review of piping supports with concrete expansion anchor R2 bolts which did not use base plates.
Such supports use structural steel members R2 (angle or channel) attached directly to the concrete by expansion anchor bolts, R2 with the piping attached to the structural steel member. The adequacy of the R2 anchor bolt design and installation should be verified to satisfy the intent of R2 the Bulletin.
R2 Action to be Taken by Licensees and Permit Holders:
This Bulletin addresses those pipe support base plates that use concrete expansion R1 anchor bolts in Seismic Category I systems as defined by Regulatory Guide 1.29,
" Seismic Design Classification" Revision 1, dated August 1973 or as defined in the applicable FSAR.
For older plants where Seismic Category I requirements did R1 not exist at the time of licensing it must be shown that piping supports for R1 safety related systems, as defined in the Final Safety Analysis Report, meet R1 design requirements.
R1 The revision is not intended to penalize licensees who have already completed some R1 of the Bulletin requirements.
In those instances in which a licensee has com-R1 pleted action on a specific item and the Bulletin revision provides more conser-R1 vative guidance, the licensee should explain the adequacy of the action already R1 performed.
It should be reiterated that the purpose of the Bulletin actions R1 are to assure operability of Seismic Category I piping systems in the event of a R1 seismic event.
R1 1.
Verify that pipe support base plate flexibility was accounted for in the cal-culation of anchor bolt loads.
In lieu of supporting analysis justifying the assumption of rigidity, the base plates should be considered flexible if the unstiffened distance between the member welded to the plate and the edge of the base plate is greater than twice the thickness of the plate.
It is R1 recognized that this criterion is conservative. Less conservative accep-R1 tance criteria must be justified and the justification submitted as part R1 of the response to the Bulletin.
If the base plate is determined to be R1 flexible, then recalculate the bolt loads using an appropriate analysis.
R1 If possible, this is to be done prior to testing of anchor bolts. These R1 calculated bolt loads are referred to hereafter as the bolt design loads.
A description of the analytical model used to verify that pipe support base R1 plate flexibility is accounted for in the calculation of anchor bolt loads R1 is to be submitted with your response to the Bulletin.
R1 1301 347
IE Bulletin No. 79-02 November 8, 1979 Revision 2 Page 3 of 7 It has been noted that the schedule for analytical work on base plate R1 flexibility for some facilities extends beyond the Bulletin reporting time R1 frame of July 6, 1979. For those facilities for which an ancht - bolt R1 testing program is required (i.e., sufficient QC documentation does not R1
, exist), the anchor bolt testing program should not be delayed.
R1 2.
Verify that the concrete expansion anchor bolts have the following minimum factor of safety between the bolt design load and the bolt ultimate capa-city determined from static load tests (e.g. anchor bolt manufacturer's) which simulate the actual conditons of installation (i.e., type of con-crete and its strength properties):
a.
Four - For wedge and sleeve type anchor bolts, b.
Five - For shell type anchor bolts.
The bolt ultimate capacity should account for the effects of shear-tension R1 interaction, minimum edge distance and proper bolt spacing.
R1 If the minimum factor of safety of four for wedge type anchor bolts and R1 five for shell type anchors can not be shown, then justification must be R1 provided. The Bulletin factors of safety were intended for the maximum R2 support load including the SSE.
The NRC has not yet been provided adequate R2 justification that lower factors of safety are acceptable on a long term R2 basis.
Lower factors of safety are allowed on an interim basis by tha R2 provisions of Supplement No. I to IE Bulletin No. 79-02.
The use of R2 reduced factors of safety in the factored load approach of ACI 349-76 has R2 not yet been accepted by the NRC.
R2 3.
Describe the design requirements if applicable for anchor bolts to with-stand cyclic loads (e.g. seismic loads and high cycle operating loads).
4.
Verify from existing QC documentation that design requirements have been met for each anchor bolt in the following areas:
(a) Cyclic loads have been considered (e.g. anchor bolt preload is equal to or gret'-r than bolt design load).
In the case of the shell type, assure that it is not in contact with the back of the support plate prior to preload testing.
(b) Specified design size and type is correctly installed (e.g. proper embedment depth).
If sufficient documentation does not exist, then initiate a testing program that will assure that minimum design requirements have been met with respect to sub-items (a) and (b) above. A sampling technique is acceptable. One acceptable technique is to randomly select and test one anchor bolt in each base plate (i.e. some supports may have more than one base plate). The test,should provide verification of sub-items (a) and (b) above.
If the test fails, all other bolts on that base plate should be similarly tested.
In any event, the test program should assure that each Seismic Category I system will perform its intended function.
' N1 348
IE Bulletin No. 79-02 November 8, 1979 Revision 2 Page 4 of 7 The preferred test method to demonstrate the bolt preload has been accom-R1 plished is using a direct pull (tensile test) equal to or greater than R1 design load. Recogni7ing this method may be difficult due to accessibility R1 in some areas an alternative test method such as torque testing may be R1 used.
If torque testing is used it must be shown and substantiateo that R1 a correlation between torque and tension exists.
If manufacturer's data R1 for the specific bolt used is not available, or is not used, then site R1 specific data must be developed by qualification tests.
R1 Bolt test values of one-fourth (wedge type) or one-fif th (shell type) of R1 bolt ultimate capacity may be used in lieu of individually calculated bolt R1 design loads where the test value can be shown to be conservative.
R1 The purpose of Bulletin No. 79-02 and this revision is to assure the R1 operability of each seismic Category I piping system.
In all cases an R1 evaluation to confirm system operability must be performed.
If a base plate R1 or anchor bolt failure rate is identified at one unit of a multi-unit site R1 which threatens operability of safety related piping systems of that unit, R1 continued operation of the remaining units at that site must be immediately R1 evaluated and reported to the NRC. The evaluation must consider the generic R1 applicability of the identified failures.
RI Appendix A describes two sampling methods for testing that can be used.
R1 Other sampling methods may be used but must be justified.
Those options R1 may be selected on a system by system basis.
R1 Justification for omitting certain bolts from sample testing which are in R1 high radiation areas during an outagt must be based on other testing or R1 analysis which substantiates operability of the affected system.
R1 Bolts which are found during the testing program not to be preloaded to R1 a load equal to or greater than bolt design load must be properly pre-R1 loaded or it must be shown that the lack of preloading is not detrimental R1 to cyclic loading capability.
Those licensees that have not verified anchor R2 bolt preload are not required to go back and establish preload. However, R2 additional information should be submitted which demonstrates the effects R2 of preload on the anchor bolt ultimate capacity under dynamic loading.
R2 If it can be established that a tension load on any of the bolts does not R1 exist for all loading cases then no preload or testing of the bolts is R1 required.
R1 If anchor bolt testing is done prior to completion of the analytical work R1 on base plate flexibility, the bolt testing must be performed to at least R1 the original calculated bolt load. For testing purposes factors may be R1 used to conservatively estimate the potential increase in the calculated R1 bolt load due to base plate flexibility.
After completion of the analytical R1 work on the base plates the conservatism of these factors must be verified.
R1 13o1 349
IE Bulletin No. 79-02 November 8, 1979 Revision 2 Page 5 of 7 For base plate supports using expansion anchors, but raised from the R1 supporting surface with grout placed under the base plate, for testing R1 purposes it must be verified that leveling nuts were not used.
If leveling R1 nuts were used, then they must be backed off such that they are not in R1 contact with the base plate before applying tension or torque testing.
R1 Bulletin No. 79-02 requires verification by inspection that bolts are R1 properly installed and are of the specified size and type.
Parameters R1 which should be included are embedment depth, thread engagement, plate R1 bolt hole size, bolt spacing, edge distance to the side of a concrete R1 member and full expansion of the shell for shell type anchor bolts.
R1 If piping systems 21/2-inch in diameter or less were computer analyzed R1 then they must be treated the same as the larger piping.
If a chart R1 analysis method was used and this method can be shown to be highly con-R1 servative, then the proper installation of the base plate and anchor bolts R1 should be verified by a sampling inspection. The parameters inspected R1 should include those described in the preceding paragraph.
If small R1 diameter piping is not inspected, then justification of system operability R1 must be provided.
R1 5.
Determine the extent that expansion anchor bolts were used in concrete block R2 (masonry) walls to attach piping supports in Seismic Category 1 systems (or R2 safety related systems as defined by Revision 1 of IE Bulletin No. 79-02).
R2 If expansion anchor bolts were used in concrete block walls:
R2 Provide a list of the systems involved, with the number of supports, R2 a.
type of anchor bolt, line size, and whether these supports are acces-R2 sible during normal plant operation.
R2 b.
Describe in detail any design consideration used to account for R2 this type of installation.
R2 Provide a detailed evaluation of the capability of the supports, R2 c.
including the anchor bolts, and block wall to meet the design R2 loads.
The evaluatior must describe how the allowable loads on anchor R2 bolts in concrete block walls were determined and also what analytical R2 method was used to determine the integrity of the block walls under the R2 imposed loads. Also describe the acceptance criteria, including the R2 numerical values, used to perform this evaluation. Review the deficien-R2 cies identified in the Information Notice on the pipe supports and walls R2 at Trojan to determine if a similar situation exists at your facility R2 with regard to supports using anchor bolts in concrete block walls.
R2 d.
Describe the results of testing of anchor bolts in concrete block R2 walls and your plans and schedule for any further action.
R2 6.
Determine the extent that pipe supports with expansion anchor bolts used R2 structural steel shapes instead of base plates. The systems and lines R2 1X91 350
IE Bulletin No. 79-02 November 8, 1979 Revision 2 Page 6 of 7 reviewed must be consistent with the criteria of IE Bulletin No. 79-02, R2 Revision 1.
If expansion anchor bolts were used as described above, verify R2 that the anchor bolt and structural steel shapes in these supports were R2 included in the actions performed for the Bulletin.
If these supports R2 cannot be verified to have been included in the Bulletin actions:
R2 Provide a list of the systems involved, with the number of supports, R2 a.
type of anchor bolt, line size, and whether the supports are acces-R2 sible during normal plant operation.
R2 b.
Provide a detailed evaluation of the adequacy of the anchor bolt design R2 and installation. The evaluation should address the assumed distribu-R2 tion of loads on the anchor bolts. The evaluation can be based on R2 the results of previous anchor bolt testing and/or analysis which R2 substantiates operability of the affected system.
R2 Describe your plans and schedule for any further action necessary to R2 c.
assure the affected systems meet Technical Specifications operability R2 requirements in the event of an SSE.
R2 7.
For those licensees that have had no extended outages to perform the testing R2 of the inaccessible anchor bolts, the testing of anchor bolts in acces-R2 sible areas is expected to be completed by November 15, 1979. The testing R2 of the inaccessible anchor bolts should be completed by the next extended R2 outage. For those licensees that have completed the anchor bolt testing R2 in inaccessible areas, the testing in accessible areas should continue R2 as rapidly as possible, but no longer than March 1, 1980.
The analysis R2 for the Bulletin items covering base plate flexibility and factors of R2 safety should be completed by November 15, 1979.
Provide a schedule R2 that details the completion dates for IE Bulletin No. 79-02, Revision 2, R2 items 1, 2, and 4.
R2 8.
Maintain documentation of any sampling inspection of anchor bolts required R2 by item 4 on site and available for NRC inspection. All holders of R2 operating licenses for power reactor facilities are requested to complete R2 items 5, 6, and 7 within 30 days of the date of issuance of Revision No. 2.
R2 Also describe any instances not previously reported, in which you did not R2 meet the revised (R2) sections of items 2 and 4 and, if necessary, your R2 plans and schedule for resolution. Report in writing within 30 days of the R2 date of this revision issuance, to the Director of the appropriate Regional R2 Office, completion of your review. For action not yet complete, a final R2 report is to be submitted upon completion of your action.
A~ copy of R2 your report (s) should be sent to the United States Nuclear Regulatory R1 Commission, Office of Inspection and Enforcement, Division of Reactor R1 Operations Inspection, Washington, D.C.
20555. These reporting require-R1 ments do not preclude nor substitute for the applicable requirements to R1 report as set forth in the regulations and license.
R1 9.
All holders of construction permits for power reactor facilities are R2 requested to complete items 5 and 6 for installed pipe supports within 60 R2 days of date of issuance of Revision No. 2.
For pipe supports which have R2
'Toi 35l
IE Brlletin No. 79-02 November 8, 1979 Revision 2 Page 7 of 7 not yet been installed, document your action to assure that items 1 through R2 6 will be satisfied. Maintain documentation of these actions on site avail-R2 able for NRC inspection. Report in writing within 60 days of date of R2 issuance of Revision No. 2, to the Director of the appropriate NRC Regional R2 Office, completion of your review and describe any instances not previously R2 reported, in which you did not meet the revised (R2) sections of items 2 and R2 4 and, if necessary, your plans and schedule for resolution. A copy of your R2 report should be sent to the United States Nuclear Regulatory Commission, R2 Office of Inspection and Enforcement, Division of Reactor Construction R2 Inspection, Washington, D.C.
20555.
R2 Approved by GA0 (R0072); clearance expires 7/31/80. Approval was h ven under a i
blanket clearance specifically for identified generic problems.
Enclosures:
1.
Appendix A R1 2.
Listing of IE Bulletins Issued In Last Six Months 1?Q 2C JJ2' I
t APPENDIX A SAMPLING METHODS Item 4 of this Bulletin states that for anchor bolt testing purposes a sampling program is acceptable. Two sampling methods are discussed below, but other methods may be used if justified.
a.
Test one bolt on each plate as originally recommended in Bulletin No. 79-02.
If the test fails, all other bolts on that base plate should be similarly tested.
A high failure rate should be the basis for increased testing.
b.
Randomly select and test a statistical sample of the bolts to provide a 95 percent confidence level that less than 5 percent defective anchors are installed in any one seismic Category I system.
The sampling program should be done on a system by system basis.
'791 353
IE Bulletin No. 79-25 Enclosure November 2, 1979 Page 1 of 3 LISTING OF IE BULLETINS ISSUED IN LAST SIX MONTHS Bulletin No.
Subject Date Issued Issued To 79-25 Failures of Westinghouse BFD 11/02/79 All Power Reactor Relays in Safety-Related Systems Facilities with an OL or a CP 79-24 Frozen Lines 9/27/79 All Power Reactor Facilities with an OL or a CP 79-23 Potential Failure of Emergency 9/12/79 All Power Reactor Diesel Gener-tor Field Exciter Facilities with an Trans fo rme '
OL or a CP 79-22 Possible Lt.. age of Tubes of 9/5/79 Each Licensee who Tritium Gas Used in Timepieces Receives Tubes of for Luminosity Tritium Gas in Time-pieces for Luminosity 79-21 Temperature Effects on Level 8/13/79 All PWR's with an Measurements Operating License 79-20 Packaging Low-Level Radioactive 8/10/79 All Materials Licensees Waste for Transport and Burial who did not receive Bulletin No. 79-19 79-19 Packaging Low-Level Radioactive 8/10/79 All Power and Research Waste for Transport and Burial Reactors with OLs, Fuel Facilities except uranium mills, and certain materials licensees 79-18 Audibility Problems Encountered 8/7/79 All OLs for Action on Evacuation of Personnel from All cps for Information High-Noise Areas 79-17 Pipe Cracks in Stagnant Borated 10/29/79 All PWRs with (Rev. 1)
Water Systems at PWR Plants Operating License 79-17 Pipe Cracks in Stagnant Borated 7/26/79 All PWRs with Water Systems at PWR Plants Operating License f
)b4
IE Bulletin No. 79-25 Enclosure November 2, 1979 Page 2 of 3 LISTING OF IE BULLETINS ISSUED IN LAST SIX MONTHS Bulletin No.
Subject Date Issued Issued To 79-16 Vital Area Access Controls 7/26/79 All Holders of'and applicants for Power Reactor Operating Licenses who Antici-page loading fuel prior to 1981 79-15 Deep Draft Pump Deficiencies 7/18/79 All Power Reactor (Supp. 1)
Licensees with a CP and/or OL 79-15 Deep Draft Pump Deficiencies 7/11/79 All Power Reactor Liceusees with a CP and/or OL 79-14 Seismic Analyses for As-Built 9/7/79 All Power Reactor (Supp. 2)
Safety-Related Piping System Facilities with an OL or a CP 79-14 Seismic Analyses for As-Built 7/27/79 All Power Reactor (Correction)
Safety-Related Piping System Facilities with an OL or a CP 79-14 Seismic Analyses for As-Built 7/18/79 All Power Reactor (Rev. 1)
Safety-Related Piping System Facilities with an OL or a CP 79-14 Seismic Analyses for As-Built 7/2/79 All Power Reactor Safety-Related Piping System Facilities with an OL or a CP 79-13 Cracking in Feedwater System 10/17/79 All PWR's with an (Rev. 2)
Piping Operating License 79-13 Cracking in Feedwater System 8/30/79 All PWR's with an (Rev. 1)
Piping Operating License 79-13 Cracking in feedwater System 6/25/79 All PWR's with an Piping OL for action. All BWRs with a CP for information 1701 355
1 IE Bulletin No. 79-25 Enclosure November 2, 1979 Page 3 of 3 LISTING OF IE BULLETINS ISSUED IN LAST SIX MONTHS Bulletin No.
Subject Date Issued Issued To 79-06C Nuclear Incident at Three Mile 7/26/79 To all PWR Power Island - Supplement Reactor Facilities with an OL 79-05C Nuclear Incident at Three 7/26/79 To all PWR Power Mile Island - Supplement Reactor Facilities with an OL 79-02 Pipe Support Base Plate Designs 11/8/79 All Power Reactor (Rev. 2)
Using Concrete Expansion Anchor Facilities with an Bolts OL or a CP 79-02 Pipe Support Base Plate Designs 8/20/79 All Power Reactor (Rev. 1)
Using Concrete Expansion Anchor Facilities with an (Supp. 1)
Bolts OL or a CP 79-02 Pipe Support Base Plate Designs 6/21/79 All Power Reactor (Rev. 1)
Using Concrete Expansion Anchor Facilities with an Bolts OL or a CP 79-01A Environmental Qualification of 6/6/79 All Power Reactor Class IE Equirment (Deficien-Facilities with an cier in the Environmental OL or a CP Qua'lification of ASCO Sole-noid Valves) i7 1 356