ML20040E650
| ML20040E650 | |
| Person / Time | |
|---|---|
| Site: | Washington Public Power Supply System |
| Issue date: | 01/29/1982 |
| From: | Sarsten G UNITED ENGINEERS & CONSTRUCTORS, INC. |
| To: | NRC OFFICE OF INSPECTION & ENFORCEMENT (IE) |
| References | |
| REF-PT21-82-556-000 PT21-82-556, PT21-82-556-000, NUDOCS 8202050210 | |
| Download: ML20040E650 (4) | |
Text
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M a constructors inc.
sosToN 30 South 17th Street cs oN Post Office Box 8223 KNOXVILLE Phu delphia, PA 19101 PHILADELPHIA a
VALLEY FORGE nh January 29, 1982 v'
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Director FED 4 19825-1 Office of Inspection and Enforcement U.S. Nuclear Regulatory Commission
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Subject:
10CFR21 Report of a Potential Defect 4
4 Related to Washington Public Power Supply System - WNP 1 and 4 Ref.: UE&C to NRC dated 12/23/81 4v-46o to-CI5
Dear Sir:
In the referenced letter UE&C informed the Commission of a potentially reportable condition under 10CFR21 regarding the design of structural steel framing for platforms within the containment.
In accordance with our commitment to the Commission UE6C evaluated the "as designed" condition and has concluded, that it is a reportable deficiency under 10CFR21.
Details as required by 10CFR21, paragraph 21.21(b) (3) are contained in the attached report.
This defect has been verbally reported to the Commission by the licensee in accordance with 10CFR 50.55e on December 28, 1981.
Very truly yourg, ll
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( G. E. Sarsten
' Vice' President - Power GV/jah Enclosure cc:
Regional Director USNRC Region 1 Regional Director USNRC - Region 5 D. Mazur Washington Public Power Supply System
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8202050210 820129 PDR ADOCK 05000460 (en.ven c,,)
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d NAME AND ADDRESS OF THE INDIVIDUAL OR INDIVIDUALS INFORMING THE COMfISSION.
G. E. Sarsten, Vice President - Power i
United Engineers & Constructors Inc.
30 South 17th Street.
Philadelphia, Pa., 19101 IDENTIFICATION OF THE FACILITY, THE ACTIVITY, OR THE BASIC COMPONENT SUPPLIED FOR SUCH FACILITY OR SUCH ACTIVITY WITHIN THE UNITED STATES WHICH 7 AILS TO COMPLY OR CONTAINS A DEFECT.
Washington Public Power Supply System, Units WNP-1 and WNP-4:
The design of structural steel platforms within the containment.
IDENTIFICATION OF THE FIRM CONSTRUCTING THE FACILITY OR SUPPLYING THE BASIC COMPONENT WHICH FAILS TO COMPLY OR CONTAINS A DEFECT.
United Engineers & Constructors Inc.
NATURE OF THE DEFECT OR FAILURE TO COMPLY AND THE SAFETY HAZARD WHICH.IS CREATED OR COULD BE CREATED BY SUCH DEFECT OR FAILURE TO COMPLY.
The steel platforms inside containment consist of structural steel framing members supported by columns or embedded steel plates anchored to concrete walls. The platforms support safety reJated systems, therefore their integrity must be assured under accident conditions as well as operating conditions.
The original design of the platforms did not consider the effects of accident temperatures.
Such effects cause secondary stresses in the framing which tend to create local overstressed conditions.
This deficiency if left uncorrected could result in failure of connections of framing members which are supporting safety related systems.
THE DATE ON WHICH THE INFORMATION OF SUCH DEFECT OR FAILURE TO COMPLY WAS OBTAINED.
December 23, 1981 IN THE CASE OF A BASIC COMPONENT WHICH CONTAINS A DEFECT OR FAILS TO COMPLY, THE NUMBER AND LOCATION OF ALL SUCH COMPONENTS IN USE AT, SUPPLIED FOR, OR BEING SUPPLIED FOR ONE OR MORE FACILITIES OR ACTIVITIES SUBJECT TO THE REGULATIONS IN THIS PART.
This design deficiency applies to all structural steel platforms within the containments of Units WNP-1 and WNP-4.
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THE CORRECTIVE ACTION WHICH HAS BEEN, IS BEING, OR WILL BE TAKEN: THE NAME OF THE INDIVIDUAL OR ORGANIZATION RESPONSIBLE FOR THE ACTION: AND THE LENGTH OF TIME HAS BEEN OR WILL BE TAKEN TO COMPLETE THE ACTION.
The corrective action consists of the following:
1.
Reanalysis of the structures considering load combinations including the effect of accident temperatures. The reanalyses are being conducted censidering the following:
a) For framing members, the overstressed conditions due to secondary thermal loads are permissible based on the ductility of ASTM-A-36 structural steel material.
Local yielding and minor distortion (i.e. buckling, elongations; etc.) of the members are permitted but failure of the framing members is not permitted and the integrity of the framing is maintained, b) The connections of the framing members are capable of resisting the reactions from those members which experience stresses beyond their elastic limit. This assures the integrity of the connection and limits a ductile behavior to only the framing member.
c) The embedded plates in the concrete walls supporting framing rembers consist of a steel face plate with Nelson studs welded for anchorage.
The embedments are capable of carrying and transferring the reactions of the framing members under all design conditions to the concrete.
Under accident temperature conditions, stresses in the anchor studs may exceed the material's elastic limit. The ductile nature of the stud material will permit elongation and therefore establishes an upper bound force in the connecting member.
The penaissible elongation will be limited to assure the integrity of the embedment.
2.
Verification of the design of the primary and secondary framing members, connections and embedmet ; anchorages.
3.
Determination of required modifications to the structure to conform to the acceptable stress and/or elongation limits.
4.
Verification of seismic design of safety related systems is adequate considering the Amplified Response Spectra (ARS) generated for the new conditions. This verification will be performed in accordance with the program reported by UE6C to the Commission by letters dated 8/8/80 and 9/10/81.
5.
Assurance of implementation of required modifications.
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The Power Division of United Engineers & Constructors Inc. is responsible for the action.
The reanalysis and design vill be completed:
1.
within the crane wall:
by February 25, 1982 2.
outside the crane wall:
by April 22, 1982 ANY ADVICE RELATED TO THE DEFECT OR FAILURE TO COMPLY ABOUT THE FACILITY, ACTIVITY, OR BASIC COMPONENT THAT HAS BEEN, IS BEING, OR WILL BE GIVEN TO PURCHASERS OR LICENSEES.
Washington Public Power Supply System will be advised of the above results.
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