ML19343B580
| ML19343B580 | |
| Person / Time | |
|---|---|
| Site: | Crystal River  |
| Issue date: | 12/19/1980 |
| From: | Baynard P FLORIDA POWER CORP. |
| To: | Reid R Office of Nuclear Reactor Regulation |
| References | |
| 3-120-35, NUDOCS 8012240274 | |
| Download: ML19343B580 (3) | |
Text
_
1,.
Florida Power j
December 19, 1980 g
File:
3-0-3-e g
3-120-35 u
U c;p,s 3
Mr. Robert W. Reid s
e Chief
- ~?
g 5
Operating Reactors Branch #4 Division of Licensing U.S. Nuclear Regulatory Commission Washington, DC 20555 Subj ect : Crystal River Unit 3 Docket No. 50-302 Operating License No. OPR-72 Use of BUNA-N in Hydraulic Snubbers
Dear Mr. Reid:
This letter is to obtain NRC approval to use BUNA-N seal material in the hydraulic snubber at Crystal River Unit 3 until the refueling outage in the Fall of 1981.
This approval is necessary for Florida Power Corpora-tion to use Technical Specification 4.7.9.1(a) for the visual surveil-lance of hydraulic snubbers in lieu of Specification 4.7.9.1(b) which requires an inspection every thirty-one (31) days.
As this material is in both Accessible and Inaccessible snubbers, the 31-day inspection would require the unit to shut down to perform the inspection.
The characteristics of BUNA-N are similar to Ethylene Propylene (EP) and are as follows:
Material RUNA-N EP Compound C-90 National Seal Co.
(5% plasticiser)
Heat Resistance Continued use <257 F Continued use <300 F (Containment de-sign tempera-ture = 281 F)
Radiation Resistance
>1.5 x 107 Rad
>5 x 106 Rad (25% damage at an absorbed dose)
Compatability with E% shrinkage Negligible hydraulic fgd (SF-9650) 1224 1 2
g General Office 3201 Thirty fourin street soutn. P O Box 14042, st Petersburg. Florida 33 e 813-866-5151
Mr. Robert W. Reid Page Two December 19, 1980 The above tabulation shows:
1.
The heat resistance of the BUNA-N and EP material are compatable.
Specifically, the BUNA-N material is de-signed for the nonnal operating temperatures at CR-3 and will not deteriorate appreciably during the short-term operability period for the snubbers during accident conditions, 2.
The radiation resistance of the BUNA-N material is. con-sistent with the EP material, and 3.
The compatability with the hydraulic fluid shows an ex-pected 5% shrinkage for the BUNA-N material.vs. negligi--
ble shrinkage for the EP material.
Considering the sta-tic application of the o-rings and the fact that only-a small amount of the seal is exposed to the fluid as the o-rings are used as an outside seal under compression, the 5% shrinkage should not affect the operability of the snubbers.
It is probable that some of this material was installed during the Spring 1979 refueling outage and inspected during the Spring 1980 re-fueling outage.
It has been confirmed that the seal material was _in-stalled in the Spring 1980 refueling outage and a partial visual inspec-tion of at least one of these snubbers was performed in 1980. -No snub-ber has ever been declared inoperable due to a failed seal, where this seal material is located.
This operating history further supports the above tabulation and conclusions that the BUNA-N material is an accepta-ble material in lieu of the EP material until the Fall 1981 outage.
Your most expeditious review of this approval request is appreciated.
Very truly yours, FLORIDA POWER CORPORATION i
N P. Y. Baynard Manager Nuclear Support Services 4
I' STATE OF FLORIDA COUNTY OF PINELLAS P.
Y. Baynard states that she is the Manager, Nuclear Support Services of Florida Power Corporation; that she is authorized on the part of said company to sign and file with the Nuclear Regulatory Commission the information attached hereto; and that all such statements made and matters set forth therein are true and correct to the best of her knowledge, information and belief.
c.
)q. 8 - J RK (f. BayW8rd Subscribed and sworn to before me, a Notary Public in and for the State and County above named, this 19th day of December,1930.
i Notary Public' Notary Public, State of Florida at Large, My Commission Expires: August 24, 1983 CrockettNotary (012)
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