ML19345C593
| ML19345C593 | |
| Person / Time | |
|---|---|
| Site: | Vermont Yankee File:NorthStar Vermont Yankee icon.png |
| Issue date: | 11/24/1980 |
| From: | Grier B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| To: | Rich Smith VERMONT YANKEE NUCLEAR POWER CORP. |
| References | |
| NUDOCS 8012050608 | |
| Download: ML19345C593 (1) | |
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UNITED STATES
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g NUCLEAR REGULATORY COMMISSION 3
l REGION I 631 PARK AVENUE
,o',4 KING OF PRUSSIA, PENNSYLVANIA 19A06
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November 24, 1980 Docket No. 50-271 Vermont Yankee Nuclear Power Corporation ATTN:
Mr. Robert L, Smith Licensing Engineer 25 Research Drive Westborough, Massachusetts 01581 I
Gentlemen:
The enclosed IE Information Notice No. 80-42, "Effect of Radiation on Hydraulic Snubber Fluid," is forwarded to you for information.
No written response is required.
If you desire additional inforfration regarding this matter, please contact this office.
S P
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r' Sincerely, R
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<3 B ce H. Grier U
Director c~
Enclosu'res:
1.
IE Information Notice No. 80-42 2.
List of Recently Issued IE Information Notices CONTACT:
D. L. Caphton (215-337-5266) cc w/encis:
Mr. Warren P. Murphy, Plant Superintendent Mr. W. F. Conway, Vice President and Manager of Operations Mr. J. E. Griffin, President Mr. L. H. Heider, Vice President h012050/o0E
SSINS No.:
6835 Acc:ssien No.:
UNITED STATES 8008220261 NUCLEAR REGULATORY COMMISSION IN 80-42 0FFICE OF INSPECTION AND ENFORCEMENT Y\\s WASHINGTON,0.C.
20555 d
November 24, 1980
/
IE Information Notice No. 80-42:
EFFECT OF RADIATION ON HYDRAULIC SNUBBER FLUID Description of~ Circumstances:
On August 7, 1980, Florida Power Corporation (FPC) filed a report in accordance with 10 CFR Part 21 that identified an upper service limit of 10 Mrad (megarad) of radiation on the General Electric Versilube F-50 fluid that was provided in Anker-Holth shock suppressors mounted on the reactor coolant pumps.
This upper limit was obtained from the results of a study performed for FPC by Rensselaer Polytechnic Institute (RPI).
These results contained two items of prime importance to the operation of the suppressors.
The first result was a significant increase of the viscosity of the fluid to the extent that incipient gelation of the fluid occurred at exposures of approximately 50 Mrad.
The viscosity increased linearly for exposures up to 20 Mrad and then increased exponentially for exposures greater than 20 Mrad.
The second result showed that hydrochloric acid (HC1) was formed in significant quantities when the fluid was subjected to radiation.
The following table lists the dose irradiation time and hcl formed.
Dose Irradiation hcl Formed (Mrad)
Time (ppm) 0 2.78 1.2 1 minute 70.3 5.8 5 minutes 329.
5.8 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> 335.
18.5 11.2 minutes 555 50.3 15.2 minutes 1592 One of the recommendations by the RPI personnel was that the fluid be replaced before a limit of approximately 6 Mrads was reached.
FPC reported that the fluid in service at Crystal River No. 3 plant had absorbed doses ranging from 2.3 to 3.6 Mrads,these values were determined by comparing the viscosity of the fluid in service to that of the test samples at RPI.
The Technical Instruction Manual that is provided by the vendor for these suppressors contains a recommendation that 12.5 Mrads should be the maximum service life for Versflube F-50.
~
This IE Information Notice is provided as an early notification of a possibly significant matter that is still under review by the NRC staff.
Recipients should review the information for possible applicability to their facilities.
No specific action or response is requested at this time.
If NRC evaluations j
so indicate, further licensee actions may be requested or required.
1 IE Information Notice No. 80-42 November 24, 1980 RECENTLY ISSUED IE INFORMATION NOTICES Information Subject Date Issued to Notice No.
Issued 80-41 Failure of Swing Check 11/10/80 All holders of Valve in the Decay Heat a power reactor Removal System at OL or CP Davis-Besse Unit No. 1 80-40 Excessive Nitrogen 11/6/80 All holders of Supply Pressure a power reactor OL Activates Safety-Relief or CP Valve Operation to Cause Reactor Depressurization 80-38 Cracking in Charging 10/30/80 All holders of Pump Casing Cladding a PWR power reactor OL or CP 80-37 Containment Cooler 10/24/80 All holders of a Leaks and Reactor power reactor OL Cavity Flooding at or CP Indian Point Unit 2 80-36 Failure of Steam 10/10/80 All holders of a Generator Support power reactor Bolting OL or CP 80-35 Leaking and Dislodged 10/10/80 All holders of a Iodine-125 Implant Category G or G1 Seeds Medical License 80-34 Baron Dilution of 9/26/80 All holders of a Reactor Coolant During PWR Power Reactor OL Steam Generator Decontamination 80-33 Determination of 9/15/80 All holders of Teletherapy Ti!aer a teletherapy Accuracy license 80-32 Clarification of 9/12/80 All holders of Certain Requirements an NRC or Agreement for Exclusive-use State License Shipments of Radioactive Materials i
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