ML20031F799
| ML20031F799 | |
| Person / Time | |
|---|---|
| Site: | Washington Public Power Supply System |
| Issue date: | 10/01/1981 |
| From: | Mazur D WASHINGTON PUBLIC POWER SUPPLY SYSTEM |
| To: | Engelken R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV) |
| References | |
| GO-1-81-330, IEB-79-02, NUDOCS 8110200439 | |
| Download: ML20031F799 (5) | |
Text
F Bulletin No. 79-02 Docket No. 50 1+60/513 Washington Public Power Supply System P.O. Box 968 3000GeorgeWashingtonWay Richland, Washington 99352 (509)372 5000 Docket Nos:
50-460 October 1, 1981 50-513 G0-1-81-330 s
Mr. R. H. Engelkeit, Director g#
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t Nuclear Regulatory Commission
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Dear Mr. Engelken:
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Subject:
NUCLEAR PROJECTS 1 AND 4
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IE BULLETIN 79-02, REVISION 2 PIPE SUPPORT BASE PLATE DESIGNS USING CONCRETE EXPANSION ANCHOR BOLTS Referencc: G01-80-278, letter, DL Renberger to RH Engelken, subject, September 25, 1980.
This letter t 'ansmits the final report concerning IE Bulletin 79-02, Revison 2.
The following addresses items that were incomplete in the reference.
1.
Verification that base plate flexibility was accounted for in calculating anchor bolt loads.
Status: Complete. See Attachment II 2.
Completion of items 1-6 for installed pipe supports with concrete anchor bolts.
Status: Complete Torque versus preload data was obtained by an on-site test, analyzed by Hilti, approved by the AE and the Supply System, and issued to the installing contractors. Attachment I gives the torque valves to be used as a result of the tests.
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-339 y; OWt kOc$xokojjg OD pg SI-75
f Mr. R. H. Engelken October 1, 1981 Page Two G0-1-81-330 3.-
Attachment II gives a brief summary of the final results of the 79-02 review.
This is the final Supply System report concerning IE Bulletin 79-02.
If you have any questions or require further information, please advise.
Very truiy yours, W
D. W. Ma Program Director, WNP-1/4 LC0/moe
Enclosure:
(Attachments I & II) cc:
Mr. H. C. Grau, UE&C-PA Mr. V. Mani, UE&C-Site (897) a l
I
ATTACHf1ENT I Pipe Support Hilti Kwik Bolt Torque Valves Size (inches)
Torque Min / Max (ft/lbs)
~
-1/2 48/55 5/8 120/130 3/4 210/230 1
340/380 1 1/4 520/570 The torque requirement is given as a range, i.e., 48 to 55 ft.1bs is acceptable.
The torque requirements based on the maximum allowable design loads for each size are to be used for all pipe support Hilti Kwik Bolts independent of the embedment depth requirements.
A_TTACHMENT II I
WASHINGTON PUBLIC POWER SUPPLY SYSTEM - UNITS 1 & 4 l
FINAL REPORT TO NRC OF RESULTS OF NUCLEAR PIPE SUPPORT DESIGN REVIEW I
Definition of Problem As a result of NRC IE Bulletins 79-02 and 79-07 and a Supply System initiated detailed design review of piping and pipe support analysis, it was decided that a comprehensive design review was necessary.
II Scope Nuclear support designs completed prior to March 7, 1980 numbered 5,976. All have been reviewed for compliance with present design requirements.
Pipe support designs completed after March 7, 1980 have addressed all the requirements of this review and are not covered by this report.
III Procedure Prior to the beginning of this review a detailed procedure was established to assure that all compone.nt, member and connection capacities were addressed.
Each support was checked for conformance to ASME III, Subsection NF and UE&C design guidelines.
Those supports having design deficiencies are in the process of design revision to corre.t the deficiency. Scheduled completion of this revision effort is tha third quarter of 1982.
Any necessary modifications to the support will be accomplished l
crithout interruption of the support erection effort, since virtually all changes will be minor and the modifications can be accomplished in the field.
IV Results Of the 5,976 nuclear supports reviewed, 2,248 were determined to have one or more deficiencies.
The major types of deficiency are welded connections and concrete expansion anchor overload. To a i
great degree, these problems were caused by the omission of friction l
loads in the original design.
I t
l
r V
Conclusion To prevent recurrence of deficiencies discovered during this review, the following actions have been implemented in current support design:
The procedure mentioned in the first paragraph of Section III of this report has been used for all support designs since flarch 7, 1980.
Its use will prevent omissions in nuclear support design.
Friction load, the major cause of the problems identified by this effort, has been incorporated in all support
. design for lines with thermal movement.
A procedure has been implemented for accounting for prying action of flexible plates against concrete expansion anchc.s.
Where the construction sequence permits, embedment plates are installed as a substitute for concrete expansion anchors.
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