ML19323F842
| ML19323F842 | |
| Person / Time | |
|---|---|
| Site: | Fermi  |
| Issue date: | 05/16/1980 |
| From: | James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| To: | Hines E DETROIT EDISON CO. |
| References | |
| NUDOCS 8005290532 | |
| Download: ML19323F842 (1) | |
Text
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e" GLEN ELLYN. lL LINols 60137 NAY 'l 61980 Docket No. 50-341 The Detroit Edison Company ATTN:
Mr. Edward Hines, Assistant Vice President and Manager Quality Assurance 2000 Second Avenue Detroit, MI 48226 Gentlemen:
This Information Notice is forwarded for information.
No written response to this Information Notice is required.
If you have any ques-tions related to this matter, please contact this office.
Sincerely, James G. Keppler
/ Director
Enclosure:
IE Information Notice No. 80-21 cc w/ encl:
Central Files Director, NRR/DPM Director, NRR/ DOR PDR Local PDR NSIC TIC Ronald Callen, Michigan Public Service Commission Eugene B. Thomas, Jr.,
Attorney se s
ln 8005200 5 3 2-V
SSINS No.: 6870 I
Accession Fo.
UNITED STATES 8005050050 NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT WASHINGTON. D.C.
20555 May 16, 1980 IE Information Notice No. 80-21 ANCHORAGE AND SUPPORT OF SAFETY-RELATED ELECTRICAL EQUIPMENT Description of Circumstances:
Seismic design evaluations in connection with the NRC Systematic Evaluation Program (SEP) have indicated a potential safety deficiency in the anchorage and support of safety-related electrical equipment. This subject was high-lighted for more in-depth evaluation af ter site visits to several facilities.
The site reviews indicated tnat equipment was supported in a non-uniform In some cases, design modifications were required to render acceptable manner.
seismic design margins. The deficiencies in anchorage and support may be due to the fact that earlier engineering design criteria did not require rigorous analyses.
Letters were issued in January 1980 to the SEP plants which requested a review of the anchorage of safety-related electrical equipment.
The findings from the reviews at Haddam Neck, Big Rock Point, Dresden 2, Oyster Creek, and Palisades identified various safety-related electrical equipment that did not have positive anchorage. The reviews at other SEP plants are continuing. A summary is provided below of those items so far identified.
Station Service Transformers Motor Control Centers (4160 V - 480V)
Cable Trays DC to AC Inverters Computer Emergency Diesel Generator Control Panels - MG Set Room Heater
- Air Compressor Batteries - Emergency Diesel
- Control Room Generator Instrument Rack
- Diesel Fire Pump Battery Room Main Breaker and
- Station Distribution Panel Station Battery Rack A related item has been identified at Comanche Peak (under construction) in which the welds to the floor supports for the main control panels were found to be undersized and improperly spaced. Also, the SEP reviewers observed that non-seismic Category I ancillary items (dolleys, gas bottles, block and tackle gear, ductwork, etc.) may be located such that they could potentially dislodge, impact, and damage safety related equipment during an earthquake.
The type of anchorage systems utilized in the SEP plants and their expected capacities vary widely. For example, high uncertainty exists relative to the capacity of non-engineered tack welds and attachments that rely on frictional clamping forces. In some cases, equipment has been found free standing with no means of positive lateral support.
(Friction being the only lateral load J
Y IE Information Notice No. 80-21 May 16, 1980 Page 2 of 2 carrying mechanism). Most of ten, heavier equipment is anchored using (1) tack
. welds to steel angles embedded in concrete; (2) clips that rely on frictional resistance; (3) concrete embedded anchor bolts; or (4) external braced frames.
Lighter equipment housed in cabinets or attached to panels or racks has been anchored using (1) bolts; (2) sheet metal screws; (3) tack welds; and (4) braced racks.
The potential concern is that certain pieces of equipment may not have adequate levels of seismic resistance capability due to limited anchorage capacity.
The potential problems relate to overturning and/or sliding of large equipment and gross movement or unacceptable forces on smaller attached equipment that may render it inoperable during an earthquake.
For certain large battery racks, this judgment is supported by analysis that predict unacceptable seismic behavior.
Section 3.10 of the Standard Review Plan provides acceptance criteria for the seismic qualification of Category I electrical equipment.
These criteria include IEEE Std. 344, " Guide for Seismic Qualification of Class 1E Electrical Equipment for Nuclear Power Generating Stations", first issued in 1971.
Facilities designed before about 1971 without benefit of such design and testing criteria may have some anchorage deficiencies.
The NRC staff is continuing to evaluate this issue on the SEP plants as part of the seismic review in the SEP. Remedial actions have been planned for the affected plants.
This Information Notice is provided as notification of a possibly significant matter.
It is expected that recipients will review the information for possible applicability to their facilities. No specific action or response is requested at this time. If NRC evaluations so indicate, additional actions may be requested or required. If you have any questions regarding this matter, please contact the Director of the appropriate NRC Regional Office.
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IE Information Notice No. 80-21 Enclosure May 16, 1980 RECENTLY ISSUED IE INFORMATION NOTICES Information Subject Date Issued To Notice No.
Issued 80-20 Loss of Decay Heat Removal 5/8/80 All light water reactor Capsbility at Davis-Besse facilities holding Unit 1 While in a Refueling power reactor OLs or cps Mooe 80-19 NIOSH Recall of Recircu-5/6/80 All holders of a power lating-Mode (Closed-Circuit) reactor OL, Research Self-Contained Breathing Reactor License, Fuel Apparatus (Rebreathers)
Cycle Facility License and Priority I Material License 80-18 Possible Weapons Smuggling 5/5/80 All power reactor Pouch fscilities with an OL, fuel fabrication and processing facilities and Materials Priority I licensees (processors and distributors) 80-17 Potential Hazards Associated 5/5/80 All radiography With Interchangable Parts Licenses On Radiographic Equipment 80-16 Shaft Seal Packing 4/29/80 All power reactor Causes Binding In Main facilities in your
(
Steam Swing Check And Region with an OL or CP Isolation Valves 80-15 Axial (Longitudinal) 4/21/80 All Light Water Reactor Oriented Cracking In Facilities holding power Piping reactor OLs or cps 80-14 Safety Suggestions From 4/2/80 All power reactor Employees facilities with an OL or CP 80-13 General Electric Type SBM 4/2/80 All light water reactor Control Switches - Defective facilities holding power Cam Followers reactor OLs or cps