ML18096B254
| ML18096B254 | |
| Person / Time | |
|---|---|
| Site: | Salem  |
| Issue date: | 02/02/1993 |
| From: | Labruna S Public Service Enterprise Group |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| Shared Package | |
| ML18096B255 | List: |
| References | |
| NLR-N92158, NUDOCS 9302120012 | |
| Download: ML18096B254 (8) | |
Text
Public Service Electric and Gas Company Stanley LaBruna Public Service Electric and Gas Company P.O. Box 236, Hancocks Bridge, NJ 08038 609-339-1200 Vice President - Nuclear Operations FEB 0 2 1993 NLR-N92158 United States Nuclear Regulatory Commission Document Control Desk Washington, DC 20555 Gentlemen:
REQUEST FOR AMENDMENT SALEM GENERATING STATION UNIT NOS. 1 AND 2 FACILITY OPERATING LICENSE NOS. DPR-70 AND DPR-75 DOCKET NOS. 50-272 AND 50-311 In accordance with the requirements of 10CFR50.90, Public Service Electric and Gas Company (PSE&G) is transmitting a request to amend Facility Operating Licenses DPR-70 and DPR-75, for Salem Generating Station (SGS) unit Nos*. 1 and 2
- Pursuant to the requirements of 10CFR50.90 (b) (1), a copy of this request has been sent to the State of New Jersey.
The proposed changes revise the provisions of Technical Specifications surveillance requirement 4.6.3.1.1, Containment Isolation Valves, as it applies to the the Feedwater Isolation valves.
As discussed in Attachment 1 to this letter, PSE&G's conclusion is that granting this request would not be a significant hazards.
This request has been reviewed and recommended for approval by the Salem Generating Station Operations Review Committee.
Attachment 110038
/----=--93021~20012 930202
- PDR ADOCK 05000272
- p PDR Sincerely,
~~~
Document Control Desk NLR-N92158 c
Mr. J. c. Stone Licensing Project Manager Mr. T. Johnson Senior Resident Inspector Mr. T. Martin, Administrator Region I Mr. Kent Tosch, Chief 2
FEB 0 2 1993 New Jersey Department of Environmental Protection Division of Environmental Quality Bureau of Nuclear Engineering CN 415 Trenton, NJ 08625
REF: NLR-N92158 STATE OF NEW JERSEY SS.
COUNTY OF SALEM
- s. LaBruna, being duly sworn according to law deposes and says:
I am Vice President - Nuclear Operations of Public Service Electric and Gas Company, and as such, I find the matters set forth in the above referenced letter, concerning the Salem Generating Station, Unit Nos. 1 and 2, are true to the best of my knowledge, information and belief.
1993 Notary PUbliC:of New Jersey KIMBERL V A. HILL NOTARY PUBLIC OF NEW JERSEY My Commission Expires March 9, 1997 I
My Gommission expires on ~~~~~~~~~~~~~~~
Page 6 of 5
NLR-N92158 ATTACHMENT 1 I.
DESCRIPTION OF THE PROPOSED CHANGES CONTAINMENT ISOLATION VALVES Table 3.6-1 VALVE NUMBER FUNCTION ISOLATION D.
- 1.
- 2.
- 3.
- 4.
- 5.
- 6.
- 7.
- 8.
D.
- 1.
2,*
- 3.
- 4.
- 5.
- 6.
- 7.
- 8.
TIME (Seconds)
FEEDWATER ISOLATION (Note 1) 11 BF 19#
Main Feedwater Isolation 59 Sec.
12 BF 19#
Main Feedwater Isolation 59 Sec.
13 BF 19#
Main Feedwater Isolation 59 Sec.
14 BF 19#
Main Feedwater Isolation 59 Sec.
11 BF 40#
Main Feedwater Isolation 59 Sec.
12 BF 40#
Main Feedwater Isolation 59 Sec.
13 BF 40#
Main Feedwater Isolation 59 Sec.
14 BF 40#
Main Feedwater Isolation 59 Sec.
Note 1: For the 11 through 14 BF19s and 11 through 1.4 BF40s a partial stroke test to ensure that the valve.is free of any stem binding is acceptable to satisfy the requirement of surveillance 4.6.3.1.1 following a packing gland adjustment to the manufacturer recommended value range.
A timed full stroke test shall be conducted the first time the Unit enters operational MODE 3 following the packing gland adjustment.
FEEDWATER ISOLATION (Note 1) 21 BF 19#
Main Feedwater Isolation
<9 Sec.
22 BF 19#
Main Feedwater Isolation
<9 Sec.
23 BF 19#
Main Feedwater Isolation 59 Sec.
24 BF 19#
Main Feedwater Isolation 59 Sec.
21 BF 40#
Main Feedwater Isolation 59 Sec.
22 BF 40#
Main Feedwater Isolation
<9 Sec.
23 BF 40#
Main Feedwater Isolation 59 Sec.
24 BF 40#
Main Feedwater Isolation 59 Sec.
Note 1: For the 21 through 24 BF19s and 21 through 24 BF40s a partial stroke test to ensure that the valve is free of any stem binding is acceptable to satisfy the requirement of surveillance 4.6.-3.1 following a packing gland adjustment to the manufacturer recommended value range.
A timed full stroke test shall be conducted the first time the Unit enters operational MODE 3 following the packing gland adjustment.
The marked-up Technical Specifications (TS) pages are included in.
Page 1 of 5
II. REASON FOR THE PROPOSED CHANGES The BF-19 valves primary function is that of feedwater control and feedwater isolation, as well as containment isolation (as a secondary function).
The valves are manufactured by Copes-Vulcan and utilize graphite packing with live loading.
The BF-40 valves are also used for feedwater isolation and containment isolation.
These valves are manufactured by Masoneilan and utilize graphite packing with live loading.
During reactor start-up and up to approximately 5% Rated Thermal Power (RTP), the steam generator levels are controlled by the Auxiliary Feedwater System with the BF19s and BF40s closed.
From approximately 5% RTP to 10% RTP, the BF-40 valves are used to control steam generator level.
At about 20% RTP the BF-40 valves will be closed and remain closed, with steam generator level maintained by the BF-19 valves.
Therefore for most of the power operations the BF19s valves are controlling steam generator water level.
Because of this constant modulation, by the BF19s, and due to the lack of guide bushings.in the bonnet, the stem is allowed to move in both the vertical and horizontal directions.
This constant stem movement allows the live load settings on the packing to loosen.
This may require occasional adjustment of the packing gland to achieve and maintain zero leakage.
Technical Specification surveillance requirement 4.6.3.1.1 and 4.6.3.1, as presently written, require that all isolation valves specified in table 3.6-1 be demonstrated OPERABLE prior to returning the valve to service after maintenance, repair or replacement work is performed on the valve or its associated actuator, control or power circuit by performance of a cycling test and verification of isolation time.
Because of these valves regulating function, a full cycling and/or timing test following a packing gland adjustment, can not be performed at power without incurring a reactor trip.
III. JUSTIFICATION AND EVALUATION OF THE SAFETY SIGNIFICANCE AND POTENTIAL CONSEQUENCES OF THE REQUEST "Maintenance" as written and used within the content of the the Technical Specification (TS) or TS surveillance requirement is not a defined (Technical Specification) term.
The feedwater isolation valves (BF19s and BF40s) are included in the PSE&G In-service Inspection Test (IST) program.
Subsection IWV paragraph 3200 of the ASME section XI defines a maintenance activity.
Page 2 of 5
The Code defines maintenance as an activity which could alter the valve performance parameter, and indicates that packing gland adjustments should be considered a maintenance activity.
consequently ASME section XI, as well as the Technical Specifications via the 4.0.5 section, requires performance of a post maintenance cycling (timing) test to demonstrate that the valve performance parameters have not been adversely affected by maintenance (packing gland adjustments).
However, the ASME code allows for exempting valves from testing requirements when it is impractical to perform such a test.
As part of the PSE&G approved IST program, these valves are exempt from their regular quarterly surveillance requirement (stroke time) during power operations, due to the inability to perform such a test.
The following paragraphs provide justification that packing gland adjustments made to the recommended manufacturer value range will not adversely affect the valve performance parameters and therefore should not be considered a "maintenance activity".
Additionally, as a result of discussions between PSE&G and Chesterton, packing manufacturer, it is believed that packing gland leakage may be due to the feedwater control function.
Chesterton recommends torquing a newly installed packing gland to a value of 13 Ft-Lbs.
This value assumes that this torque is applied with clean, lubricated studs and no system pressure acting on the packing.
However, a higher torque value is expected for an equivalent packing load when the system is at normal pressure, temperature, with relatively unlubricated studs.
This is due to the lubricant drying as a result of any packing leaks.
PSE&G discussions with Copes Vulcan (valve.manufacturer) concluded that the present required.Technical Specification stroke time (nine seconds) will not be exceeded,'- if the torque value does not exceed 20 Ft-Lbs.
This value is based upon Copes Vulcan data and Salem specific historical data from *past packing gland adjustments, which is presented below.
Based on the above information and the vendor's agreement, that retorquing the hold down nuts to the presently recommended torque value will not adversely affect the closure time, the appropriate maintenance procedure has been modified to reflect the acceptable torque value range.
NOTE PSE&G research into the workorder system indicates that there has not been any special work, modification or significant design change implemented that would cause different results from those presented below.
Page 3 of 5
PSE&G successfully performed packing gland adjustment at power, with NRC approval, in 1987 and 1988.
In April 1987, 22BF19 packing was adjusted to 13 Ft-Lbs.
In June 1987, 23BF19 packing was adjusted to 21 Ft-Lbs, at 2Ft-Lbs intervals to stop the leak.
In October 1987, 22BF19 packing was adjusted to 17Ft-Lbs.
In July 1988, 11BF19 packing was adjusted to 19Ft-Lbs.
Following these packing gland adjustments the valves were partially stroked to ensure free stem movement.
When plant conditions allowed, the valves were timed in accordance with Technical Specifications requirements.
The resultant stroke times were; 4.8, 4.3, 4.8 and 5.5 seconds respectively.
Note that the presently required Technical Specification closure time is nine seconds.
After recent discussion with NRC Region I and NRR personnel, PSE&G adjusted the 12BF19 packing gland to minimize a severe leak.
On October 1, 1992, the 12BF19 valve was torqued to 13 Ft-Lbs, the original recommended (Chesterton) value to minimize a severe packing leak.
At that time the as found torque value was measured at lOFt-Lbs.
To stop the leak the valve packing gland was adjusted again, on October 4 1992, to 16Ft-Lbs.
on both occasions a partial stroke test was conducted to ensure free movement of the valve stem.
NOTE: In late October the Unit shut-down to repack the valve.
A full cycle time stroke was not conducted due to the relaxation of the packing gland.
The left and right packing gland hold down nuts (as found torque) was measured at 9 and 10 Ft-Lbs respectively.
The Salem Technical Specifications Basis, is as follows:
"The OPERABILITY of the containment isolation valves ensures that the containment atmosphere will be isolated from the outside environment in the event of a release of radioactive material to the containment atmosphere or pressurization of the containment.
Containment isolation within the time limits specified ensures that the release of radioactive material to the environment will be consistent with the assumptions used in the analyses for a LOCA. 11 Additionally, excessive feedwater flow is an accident analyzed in the Salem UFSAR, and it bounds the failure of a BF19 valve to close (most severe single failure).
The Salem design employs several back-up features to the BF19s and BF40s for feedwater isolation and containment isolation.
The motor operated valve BF13 (remotely operated from the control room with a 30 sec closure time) serves as a back-up feedwater isolation valve; thus main feed water can be isolated to the steam generators even if the BF19s stroke time was affected to the point of the valve failing to close.
Page 4 of 5
The BF22 backs-up the BF19 function as a containment isolation valve (prevent back flow from containment).
This valve is a motor operated stop check valve that can be remotely operated from the control room to ensure positive isolation.
The check valve will automatically close upon loss of flow (no motive power needed), and will become leak tight upon manual energization of the motor operator from the control room.
IV. DETERMINATION OF NO SIGNIFICANT HAZARDS CONSIDERATION This proposed Amendment request:
- 1.
Does not involve a significant increase in the probability or consequences of an accident previously evaluated.
Packing gland adjustment is not an accident initiator; therefore the probability or consequences of an accident previously evaluated are not increased.
The request does not involve an exemption from testing, but rather proposes an alternate test to verify functional operability of the components.
The proposed partial stroke test will ensure no stem binding and free movement of the valve and therefore assuring functional ability of the valve to close.
- 2.
Does not create the possibility of a new or different kind of accident from any accident previously evaluated.
The partial stroke test will ensure that there is no stem binding and that the valve will move freely.
The request does not introduce any design or physical configuration changes to the facility which could create new accident scenarios.
- 3.
Does not involve a significant reduction in a margin of safety.
The redundancy in protection afforded by other valves in the feedwater piping loops {BF13 and BF22) assures that positive isolation can be achieved.
Additionally, PSE&G historical data from previous adjustment, supports the conclusion that adjusting the packing gland to the maximum recommended values will not exceed the required Technical Specification isolation times.
Therefore the request does not involve a significant reduction in a margin of safety.
Page 5 of 5