CNL-17-141, Tennessee Valley Authority - Anchor Darling Double Disc Gate Valve Information and Status
| ML17362A566 | |
| Person / Time | |
|---|---|
| Site: | Browns Ferry, Watts Bar, Sequoyah  |
| Issue date: | 12/28/2017 |
| From: | James Shea Tennessee Valley Authority |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| CNL-17-141 | |
| Download: ML17362A566 (10) | |
Text
Tennessee Valley Authority, 1101 Market Street, Chattanooga, Tennessee 37402 CNL-17-141 December 28, 2017 10 CFR 50.4 ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Washington, D.C. 20555-0001 Browns Ferry Nuclear Plant, Units 1, 2, and 3 Renewed Facility Operating License Nos. DPR-33, DPR-52, and DPR-68 NRC Docket Nos. 50-259, 50-260, and 50-296 Sequoyah Nuclear Plant, Units 1 and 2 Renewed Facility Operating License Nos. DPR-77 and DPR-79 NRC Docket Nos. 50-327 and 50-328 Watts Bar Nuclear Plant, Units 1 and 2 Facility Operating License Nos. NPF-90 and NPF-96 NRC Docket Nos. 50-390 and 50-391
Subject:
TENNESSEE VALLEY AUTHORITY - ANCHOR DARLING DOUBLE DISC GATE VALVE INFORMATION AND STATUS
References:
- 1. Nuclear Energy Institute (NEI) letter to NRC, Anchor Darling Double Disc Gate Valve Industry Resolution Plan Update (Project 689),
dated August 4, 2017 (ML17220A363)
- 2. NEI letter to NRC, NSIAC Concurrence on Anchor Darling Double Disc Gate Valve Industry Response Actions (Project 689), dated October 26, 2017 (ML17303A031)
- 3. BWROG Topical Report TP16-1-112, Revision 4, Recommendations to Resolve Flowserve 10 CFR Part 21 Notification Affecting Anchor Darling Double Disc Gate Valve Wedge Pin Failures, dated August 2017
U.S. Nuclear Regulatory Commission CNL-17-141 Page 2 December 28, 2017 By letter dated August 4, 2017 (Reference 1), the Nuclear Energy Institute (NEI) provided the NRC a resolution plan for the U.S. nuclear industry to address the known Anchor Darling Double Disk Gate Valve (ADDDGV) issues. By letter dated October 26, 2017 (Reference 2),
NEI informed NRC that each utility would provide a listing of their Anchor Darling valve population with active safety functions along with relevant valve information, including the results of susceptibility evaluations, repair status, and a repair schedule for each susceptible valve not yet repaired. This letter serves to provide this information for Sequoyah Nuclear Plant (SQN), Units 1 and 2.
For Browns Ferry Nuclear Plant, Units 1, 2, and 3, this letter provides the available information. However, TVA has not completed its review of the Browns Ferry Anchor Darling valve population, so the repair schedule cannot be provided at this time. TVA will provide this information after the necessary repairs have been identified.
This letter is also to confirm that Watts Bar Nuclear Plant (WBN), Units 1 and 2, does not use ADDDGVs to support any active safety function.
Enclosures 1 and 2 to this letter contain the following information for each BFN and SQN ADDDGV motor-operated valve, respectively.
Plant Name, Unit, and Valve ID.
System.
Valve Functional Description.
Valve Size.
Active Safety Function (open, close, both).
Are multiple design basis post-accident strokes required (yes/no)?
Expert Panel Risk Ranking (high, medium, low).
Result of susceptibility evaluation (susceptible or not susceptible).
Is the susceptibility evaluation in general conformance with TP16-1-112R4 (Reference 3)?
Does the susceptibility evaluation rely on thread friction? If yes, was the COF greater than 0.10? For cases where thread-friction was relied upon, information is provided whether the coefficient of friction was above or below 0.1.
Was an initial stem-rotation check performed? If yes, include rotation criteria (i.e. 10 degrees or 5 degrees).
Was the diagnostic test data reviewed for failure precursors described in TP16-1-112R4 (Reference 3)?
The valves repair status (i.e. repaired or not repaired).
A repair schedule for each susceptible valve.
The new regulatory commitments contained in this letter are included in Enclosure 3.
U.S. Nuclear Regulatory Commission CNL-17-141 Page 3 December 28, 2017 If you have any questions regarding this submittal, please contact Russell Thompson at (423) 751-2567.
- &~~
J. W. Shea Vice President, Nuclear Regulatory Affairs and Support Services
Enclosures:
- 1. Browns Ferry Nuclear Plant, Units 1, 2, and 3 - Anchor Darling Double Disc Gate Valve Information
- 2. Sequoyah Nuclear Plant, Units 1 and 2 - Anchor Darling Double Disc Gate Valve Information
- 3. Summary of Commitments cc (Enclosures):
NRR Director - NRC Headquarters NRC Regional Administrator - Region II NRC Project Manager - Browns Ferry Nuclear Plant NRC Project Manager - Sequoyah Nuclear Plant NRC Project Manager - Watts Bar Nuclear Plant NRC Senior Resident Inspector - Browns Ferry Nuclear Plant NRC Senior Resident Inspector - Sequoyah Nuclear Plant NRC Senior Resident Inspector - Watts Bar Nuclear Plant Browns Ferry Nuclear Plant, Units 1, 2, and 3 - Anchor Darling Double Disc Gate Valve Information Notes: (1) Stem/wedge connection is a T-head. Not repaired due to not being susceptible.
(2) Wedge pin was replaced with an Inconel pin and wedge pin analysis determined new pin is satisfactory.
(3) Pin shear will not affect valve performance. If the pin sheared the applied torque would tighten the stem to upper wedge and there would be no loose parts since the pin is peened on both ends and broken parts would be captured in the upper wedge (See PDO for PER 692133, Rev 2).
(4) Determine if valve has a pressed-on stem collar. (CR# 1334283).
(5) Original pin remains installed and wedge pin analysis determined pin is satisfactory.
Page E1-1 of 3 Plant Name Unit Valve ID System Valve Functional Description Valve Size (inches)
Active Safety Function Are multiple design basis post-accident strokes required?
Expert Panel Risk Ranking Result of susceptibility evaluation Is the susceptibility evaluation in general conformance with TP16-1-112R4?
Does the susceptibility evaluation rely on thread friction?
If yes, was the COF greater than 0.10?
Was an initial stem-rotation check performed?
If yes, include rotation criteria Was the diagnostic test data reviewed for failure precursors described in TP16-1-112R4?
Valve repair status (Open, Close, Both)
(Yes/No)
(High,
- Medium, Low)
(Susceptible or not susceptible)
(Yes/No)
(No),
(Yes, >0.10),
(Yes, 0.10)
(No),
(Yes, 10 deg.),
(Yes, 5 deg.)
(Yes/ No)
(repaired or not repaired)
Browns Ferry 1
1-FCV-001-0055 Main Steam MAIN STEAM LINE DRAIN INBOARD ISOLATION VALVE 3
Close No Low Not Susceptible(1)
Yes (1)
No No No Not Repaired(1)
Browns Ferry 1
1-FCV-001-0056 Main Steam MAIN STEAM LINE DRAIN OUTBOARD ISOLATION VALVE 3
Close No Low Not Susceptible(1)
Yes (1)
No No No Not Repaired(1)
Browns Ferry 1
1-FCV-068-0003 Reactor Recircula tion REACTOR RECIRC PUMP 'A' DISCHARGE VALVE 24 Close No Low Susceptible(4)
Yes (3)
No (3)
Yes, 5 deg.
Yes Not Repaired(3) (4)
Browns Ferry 1
1-FCV-068-0079 Reactor Recircula tion REACTOR RECIRC PUMP 'B' DISCHARGE VALVE 24 Close No Low Susceptible(4)
Yes (3)
No (3)
Yes, 5 deg.
Yes Not Repaired(3) (4)
Browns Ferry 1
1-FCV-069-0001 Reactor Water Cleanup RWCU INBOARD CONTAINMENT ISOLATION VALVE 6
Close No Medium Susceptible(4)
Yes (2)
No No Yes Repaired (2) (4)
Browns Ferry 1
1-FCV-069-0002 Reactor Water Clean-Up RWCU OUTBOARD CONTAINMENT ISOLATION VALVE 6
Close No Medium Susceptible(4)
Yes (2)
Yes, >0.10 No Yes Repaired (2) (4)
Browns Ferry 1
1-FCV-071-0002 Reactor Core Isolation Coolant RCIC STEAM SUPPLY INBOARD CONTAINMENT ISOLATION VALVE 3
Close No Medium Not Susceptible(1)
Yes (1)
No No No Not Repaired(1)
Browns Ferry 1
1-FCV-071-0003 Reactor Core Isolation Coolant RCIC STEAM SUPPLY OUTBOARD CONTAINMENT ISOLATION VALVE 3
Close No Medium Not Susceptible(1)
Yes (1)
No No No Not Repaired(1)
Browns Ferry 1
1-FCV-073-0002 High Pressure Coolant Injection HPCI INBOARD CONTAINMENT ISOLATION VALVE 10 Close No Medium Susceptible(4)
Yes (2)
Yes, >0.10 No Yes Repaired (2) (4)
Browns Ferry 1
1-FCV-073-0003 High Pressure Coolant Injection HPCI OUTBOARD CONTAINMENT ISOLATION VALVE 10 Close No Medium Susceptible(4)
Yes (2)
Yes, >0.10 No Yes Repaired (2) (4)
Browns Ferry 1
1-FCV-073-0081 High Pressure Coolant Injection HPCI OUTBOARD CONTAINMENT ISOLATION BYPASS VALVE 1
Close No Low Not Susceptible(1)
Yes (1)
No No No Not Repaired(1)
Browns Ferry 1
1-FCV-075-0009 Core Spray CORE SPRAY SYSTEM I MINIMUM FLOW VALVE 3
Both Yes Low Susceptible(4)
Yes (5)
Yes, >0.10 Yes, 5 deg.
Yes Not Repaired(4) (5)
Browns Ferry Nuclear Plant, Units 1, 2, and 3 - Anchor Darling Double Disc Gate Valve Information Notes: (1) Stem/wedge connection is a T-head. Not repaired due to not being susceptible.
(2) Wedge pin was replaced with an Inconel pin and wedge pin analysis determined new pin is satisfactory.
(3) Pin shear will not affect valve performance. If the pin sheared the applied torque would tighten the stem to upper wedge and there would be no loose parts since the pin is peened on both ends and broken parts would be captured in the upper wedge (See PDO for PER 692133, Rev 2).
(4) Determine if valve has a pressed-on stem collar. (CR# 1334283).
(5) Original pin remains installed and wedge pin analysis determined pin is satisfactory.
Page E1-2 of 3 Plant Name Unit Valve ID System Valve Functional Description Valve Size (inches)
Active Safety Function Are multiple design basis post-accident strokes required?
Expert Panel Risk Ranking Result of susceptibility evaluation Is the susceptibility evaluation in general conformance with TP16-1-112R4?
Does the susceptibility evaluation rely on thread friction?
If yes, was the COF greater than 0.10?
Was an initial stem-rotation check performed?
If yes, include rotation criteria Was the diagnostic test data reviewed for failure precursors described in TP16-1-112R4?
Valve repair status (Open, Close, Both)
(Yes/No)
(High,
- Medium, Low)
(Susceptible or not susceptible)
(Yes/No)
(No),
(Yes, >0.10),
(Yes, 0.10)
(No),
(Yes, 10 deg.),
(Yes, 5 deg.)
(Yes/ No)
(repaired or not repaired)
Browns Ferry 1
1-FCV-075-0037 Core Spray CORE SPRAY SYSTEM II MINIMUM FLOW VALVE 3
Both Yes Low Susceptible(4)
Yes (5)
Yes, >0.10 Yes, 5 deg.
Yes Not Repaired(4) (5)
Browns Ferry 2
2-FCV-001-0055 Main Steam MAIN STEAM LINE DRAIN INBOARD ISOLATION VALVE 3
Close No Low Not Susceptible(1)
Yes (1)
No No No Not Repaired(1)
Browns Ferry 2
2-FCV-001-0056 Main Steam MAIN STEAM LINE DRAIN OUTBOARD ISOLATION VALVE 3
Close No Low Not Susceptible(1)
Yes (1)
No No No Not Repaired(1)
Browns Ferry 2
2-FCV-068-0003 Reactor Recircula tion REACTOR RECIRC PUMP 'A' DISCHARGE VALVE 24 Close No Low Susceptible(4)
Yes (3)
No (3)
Yes, 5 deg.
Yes Not Repaired(3) (4)
Browns Ferry 2
2-FCV-068-0079 Reactor Recircula tion REACTOR RECIRC PUMP 'B' DISCHARGE VALVE 24 Close No Low Susceptible(4)
Yes (3)
No (3)
Yes, 5 deg.
Yes Not Repaired(3) (4)
Browns Ferry 2
2-FCV-069-0001 Reactor Water Cleanup RWCU INBOARD CONTAINMENT ISOLATION VALVE 6
Close No Medium Susceptible(4)
Yes (2)
No No Yes Repaired (2) (4)
Browns Ferry 2
2-FCV-069-0002 Reactor Water Cleanup RWCU OUTBOARD CONTAINMENT ISOLATION VALVE 6
Close No Medium Susceptible(4)
Yes (2)
Yes, >0.10 No Yes Repaired (2) (4)
Browns Ferry 2
2-FCV-071-0002 Reactor Core Isolation Coolant RCIC STEAM SUPPLY INBOARD CONTAINMENT ISOLATION VALVE 3
Close No Medium Not Susceptible(1)
Yes (1)
No No No Not Repaired(1)
Browns Ferry 2
2-FCV-071-0003 Reactor Core Isolation Coolant RCIC STEAM SUPPLY OUTBOARD CONTAINMENT ISOLATION VALVE 3
Close No Medium Not Susceptible(1)
Yes (1)
No No No Not Repaired(1)
Browns Ferry 2
2-FCV-073-0002 High Pressure Coolant Injection HPCI INBOARD CONTAINMENT ISOLATION VALVE 10 Close No Medium Susceptible(4)
Yes (2)
Yes, >0.10 No Yes Repaired (2) (4)
Browns Ferry 2
2-FCV-073-0003 High Pressure Coolant Injection HPCI OUTBOARD CONTAINMENT ISOLATION VALVE 10 Close No Medium Susceptible(4)
Yes (2)
Yes, >0.10 No Yes Repaired (2) (4)
Browns Ferry 2
2-FCV-073-0081 High Pressure Coolant Injection HPCI OUTBOARD CONTAINMENT ISOLATION BYPASS VALVE 1
Close No Low Not Susceptible(1)
Yes (1)
No No No Not Repaired(1)
Browns Ferry Nuclear Plant, Units 1, 2, and 3 - Anchor Darling Double Disc Gate Valve Information Notes: (1) Stem/wedge connection is a T-head. Not repaired due to not being susceptible.
(2) Wedge pin was replaced with an Inconel pin and wedge pin analysis determined new pin is satisfactory.
(3) Pin shear will not affect valve performance. If the pin sheared the applied torque would tighten the stem to upper wedge and there would be no loose parts since the pin is peened on both ends and broken parts would be captured in the upper wedge (See PDO for PER 692133, Rev 2).
(4) Determine if valve has a pressed-on stem collar. (CR# 1334283).
(5) Original pin remains installed and wedge pin analysis determined pin is satisfactory.
Page E1-3 of 3 Plant Name Unit Valve ID System Valve Functional Description Valve Size (inches)
Active Safety Function Are multiple design basis post-accident strokes required?
Expert Panel Risk Ranking Result of susceptibility evaluation Is the susceptibility evaluation in general conformance with TP16-1-112R4?
Does the susceptibility evaluation rely on thread friction?
If yes, was the COF greater than 0.10?
Was an initial stem-rotation check performed?
If yes, include rotation criteria Was the diagnostic test data reviewed for failure precursors described in TP16-1-112R4?
Valve repair status (Open, Close, Both)
(Yes/No)
(High,
- Medium, Low)
(Susceptible or not susceptible)
(Yes/No)
(No),
(Yes, >0.10),
(Yes, 0.10)
(No),
(Yes, 10 deg.),
(Yes, 5 deg.)
(Yes/ No)
(repaired or not repaired)
Browns Ferry 3
3-FCV-001-0055 Main Steam MAIN STEAM LINE DRAIN INBOARD ISOLATION VALVE 3
Close No Low Not Susceptible(1)
Yes (1)
No No No Not Repaired(1)
Browns Ferry 3
3-FCV-001-0056 Main Steam MAIN STEAM LINE DRAIN OUTBOARD ISOLATION VALVE 3
Close No Low Not Susceptible(1)
Yes (1)
No No No Not Repaired(1)
Browns Ferry 3
3-FCV-068-0003 Reactor Recircula tion REACTOR RECIRC PUMP 'A' DISCHARGE VALVE 24 Close No Low Susceptible(4)
Yes (3)
No (3)
Yes, 5 deg.
Yes Not Repaired(3) (4)
Browns Ferry 3
3-FCV-068-0079 Reactor Recircula tion REACTOR RECIRC PUMP 'B' DISCHARGE VALVE 24 Close No Low Susceptible(4)
Yes (3)
No (3)
Yes, 5 deg.
Yes Not Repaired(3) (4)
Browns Ferry 3
3-FCV-069-0001 Reactor Water Cleanup RWCU INBOARD CONTAINMENT ISOLATION VALVE 6
Close No Medium Susceptible(4)
Yes (2)
Yes, >0.10 No Yes Repaired (2) (4)
Browns Ferry 3
3-FCV-069-0002 Reactor Water Cleanup RWCU OUTBOARD CONTAINMENT ISOLATION VALVE 6
Close No Medium Susceptible(4)
Yes (2)
Yes, >0.10 No Yes Repaired (2) (4)
Browns Ferry 3
3-FCV-071-0002 Reactor Core Isolation Coolant RCIC STEAM SUPPLY INBOARD CONTAINMENT ISOLATION VALVE 3
Close No Medium Not Susceptible(1)
Yes (1)
No No No Not Repaired(1)
Browns Ferry 3
3-FCV-071-0003 Reactor Core Isolation Coolant RCIC STEAM SUPPLY OUTBOARD CONTAINMENT ISOLATION VALVE 3
Close No Medium Not Susceptible(1)
Yes (1)
No No No Not Repaired(1)
Browns Ferry 3
3-FCV-073-0002 High Pressure Coolant Injection HPCI INBOARD CONTAINMENT ISOLATION VALVE 10 Close No Medium Susceptible(4)
Yes (2)
Yes, >0.10 No Yes Repaired (2) (4)
Browns Ferry 3
3-FCV-073-0003 High Pressure Coolant Injection HPCI OUTBOARD CONTAINMENT ISOLATION VALVE 10 Close No Medium Susceptible(4)
Yes (2)
Yes, >0.10 No Yes Repaired (2) (4)
Browns Ferry 3
3-FCV-073-0081 High Pressure Coolant Injection HPCI OUTBOARD CONTAINMENT ISOLATION BYPASS VALVE 1
Close No Low Not Susceptible(1)
Yes (1)
No No No Not Repaired(1)
Sequoyah Nuclear Plant, Units 1 and 2 - Anchor Darling Double Disc Gate Valve Information Notes: (A) Applied Wedge Pin Torque must bound anticipated design basis operating torque requirements and current maximum total torque (1) The repair of this MOV included upgrading the pin material to Inconel 718, and torqueing the stem/wedge connection to a value equal to greater than the valve operating torque requirements and the maximum allowable setup valve total torque. A Flowserve analysis has been performed to demonstrate the repaired valve will withstand the maximum Sequoyah valve operating loads. The combination of applied stem/wedge torque and upgraded pin analysis provides additional design margin. Reference Appendix I (2) The maximum allowed stem assembly force calculation uses a thread factor and the collar to wedge friction. This is just used to determine the maximum allowable torque of the stem to upper wedge. The evaluation does not rely on an additional thread frictional force to counteract the operating torque. The connection torque capability is based on the sum of the installed torque of the upper wedge to stem and the strength of the pin.
(3) Repair scheduled for U1C22 refueling outage.
(4) Repair scheduled for U2C22 refueling outage.
Page E2-1 of 3 Plant Name Unit Valve ID System Valve Functional Description Valve Size (inches)
Active Safety Function Are multiple design basis post-accident strokes required?
Expert Panel Risk Ranking Result of susceptibility evaluation Is the susceptibility evaluation in general conformance with TP16-1-112R4?(A)
Does the susceptibility evaluation rely on thread friction?
If yes, was the COF greater than 0.10?
Was an initial stem-rotation check performed?
If yes, include rotation criteria Was the diagnostic test data reviewed for failure precursors described in TP16-1-112R4?
Valve repair status (Open, Close, Both)
(Yes/No)
(High,
- Medium, Low)
(susceptible or not susceptible)
(Yes/No)
(No),
(Yes, >0.10),
(Yes, 0.10)
(No),
(Yes, 10 deg.),
(Yes, 5 deg.)
(Yes/ No)
(repaired or not repaired)
Sequoyah 1
1-FCV-063-0008-A Safety Injection RHR HTX A TO CVCS CHG PUMPS 8
Open/Close No High Not Susceptible Yes No(2)
No Yes Repaired(1)
Sequoyah 1
1-FCV-063-0011-B Safety Injection RHR HTX B TO SIS PUMPS 8
Open/Close No High Not Susceptible Yes No(2)
No Yes Repaired(1)
Sequoyah 1
1-FCV-063-0022-B Safety Injection SIS PUMPS COLD LEG INJ 4
Open/Close Yes Low Susceptible Yes No(2)
No Yes Not repaired(3)
Sequoyah 1
1-FCV-063-0025-B Safety Injection SIS CCP INJ TANK SHUTOFF VLV 4
Open/Close Yes Low Not Susceptible Yes No(2)
No Yes Repaired(1)
Sequoyah 1
1-FCV-063-0026-A Safety Injection SIS CCP INJ TANK SHUTOFF VLV 4
Open/Close Yes Low Not Susceptible Yes No(2)
No Yes Repaired(1)
Sequoyah 1
1-FCV-063-0039-A Safety Injection SIS CCP INJ TANK INLET SHUTOFF VLV 4
Open/Close Yes Low Not Susceptible Yes No(2)
No Yes Repaired(1)
Sequoyah 1
1-FCV-063-0040-B Safety Injection SIS CCP INJ TANK INLET SHUTOFF VLV 4
Open/Close Yes Low Not Susceptible Yes No(2)
No Yes Repaired(1)
Sequoyah 1
1-FCV-063-0072-A Safety Injection CONTAINMENT SUMP FLOW ISOL VLV 18 Open/Close Yes High Not Susceptible Yes No(2)
No Yes Repaired(1)
Sequoyah 1
1-FCV-063-0073-B Safety Injection CONTAINMENT SUMP FLOW ISOL VLV 18 Open/Close Yes High Not Susceptible Yes No(2)
No Yes Repaired(1)
Sequoyah Nuclear Plant, Units 1 and 2 - Anchor Darling Double Disc Gate Valve Information Notes: (A) Applied Wedge Pin Torque must bound anticipated design basis operating torque requirements and current maximum total torque (1) The repair of this MOV included upgrading the pin material to Inconel 718, and torqueing the stem/wedge connection to a value equal to greater than the valve operating torque requirements and the maximum allowable setup valve total torque. A Flowserve analysis has been performed to demonstrate the repaired valve will withstand the maximum Sequoyah valve operating loads. The combination of applied stem/wedge torque and upgraded pin analysis provides additional design margin. Reference Appendix I (2) The maximum allowed stem assembly force calculation uses a thread factor and the collar to wedge friction. This is just used to determine the maximum allowable torque of the stem to upper wedge. The evaluation does not rely on an additional thread frictional force to counteract the operating torque. The connection torque capability is based on the sum of the installed torque of the upper wedge to stem and the strength of the pin.
(3) Repair scheduled for U1C22 refueling outage.
(4) Repair scheduled for U2C22 refueling outage.
Page E2-2 of 3 Plant Name Unit Valve ID System Valve Functional Description Valve Size (inches)
Active Safety Function Are multiple design basis post-accident strokes required?
Expert Panel Risk Ranking Result of susceptibility evaluation Is the susceptibility evaluation in general conformance with TP16-1-112R4?(A)
Does the susceptibility evaluation rely on thread friction?
If yes, was the COF greater than 0.10?
Was an initial stem-rotation check performed?
If yes, include rotation criteria Was the diagnostic test data reviewed for failure precursors described in TP16-1-112R4?
Valve repair status (Open, Close, Both)
(Yes/No)
(High,
- Medium, Low)
(susceptible or not susceptible)
(Yes/No)
(No),
(Yes, >0.10),
(Yes, 0.10)
(No),
(Yes, 10 deg.),
(Yes, 5 deg.)
(Yes/ No)
(repaired or not repaired)
Sequoyah 1
1-FCV-074-0003-A Residual Heat Removal RHR PUMP A-A INLET FLOW CONTROL VLV 14 Open/Close No High Not Susceptible Yes No(2)
No Yes Repaired(1)
Sequoyah 1
1-FCV-074-0021-B Residual Heat Removal RHR PUMP B-B INLET FLOW CONTROL VLV 14 Open/Close No High Not Susceptible Yes No(2)
No Yes Repaired(1)
Sequoyah 1
1-FCV-074-0033-A Residual Heat Removal RHR HT EXCH A BYPASS 8
Open/Close Yes Medium Susceptible Yes No(2)
No Yes Not repaired(3)
Sequoyah 1
1-FCV-074-0035-B Residual Heat Removal RHR HT EXCH B BYPASS 8
Open/Close Yes Medium Susceptible Yes No(2)
No Yes Not repaired(3)
Sequoyah 2
2-FCV-063-0008-A Safety Injection RHR HTX A TO CVCS CHG PUMPS 8
Open/Close No High Not Susceptible Yes No(2)
No Yes Repaired(1)
Sequoyah 2
2-FCV-063-0011-B Safety Injection RHR HTX B TO SIS PUMPS 8
Open/Close No High Not Susceptible Yes No(2)
No Yes Repaired(1)
Sequoyah 2
2-FCV-063-0022-B Safety Injection SIS PUMPS COLD LEG INJ 4
Open/Close Yes Low Susceptible Yes No(2)
No Yes Not repaired(4)
Sequoyah 2
2-FCV-063-0025-B Safety Injection SIS CCP INJ TANK SHUTOFF VLV 4
Open/Close Yes Low Not Susceptible Yes No(2)
No Yes Repaired(1)
Sequoyah 2
2-FCV-063-0026-A Safety Injection SIS CCP INJ TANK SHUTOFF VLV 4
Open/Close Yes Low Not Susceptible Yes No(2)
No Yes Repaired(1)
Sequoyah Nuclear Plant, Units 1 and 2 - Anchor Darling Double Disc Gate Valve Information Notes: (A) Applied Wedge Pin Torque must bound anticipated design basis operating torque requirements and current maximum total torque (1) The repair of this MOV included upgrading the pin material to Inconel 718, and torqueing the stem/wedge connection to a value equal to greater than the valve operating torque requirements and the maximum allowable setup valve total torque. A Flowserve analysis has been performed to demonstrate the repaired valve will withstand the maximum Sequoyah valve operating loads. The combination of applied stem/wedge torque and upgraded pin analysis provides additional design margin. Reference Appendix I (2) The maximum allowed stem assembly force calculation uses a thread factor and the collar to wedge friction. This is just used to determine the maximum allowable torque of the stem to upper wedge. The evaluation does not rely on an additional thread frictional force to counteract the operating torque. The connection torque capability is based on the sum of the installed torque of the upper wedge to stem and the strength of the pin.
(3) Repair scheduled for U1C22 refueling outage.
(4) Repair scheduled for U2C22 refueling outage.
Page E2-3 of 3 Plant Name Unit Valve ID System Valve Functional Description Valve Size (inches)
Active Safety Function Are multiple design basis post-accident strokes required?
Expert Panel Risk Ranking Result of susceptibility evaluation Is the susceptibility evaluation in general conformance with TP16-1-112R4?(A)
Does the susceptibility evaluation rely on thread friction?
If yes, was the COF greater than 0.10?
Was an initial stem-rotation check performed?
If yes, include rotation criteria Was the diagnostic test data reviewed for failure precursors described in TP16-1-112R4?
Valve repair status (Open, Close, Both)
(Yes/No)
(High,
- Medium, Low)
(susceptible or not susceptible)
(Yes/No)
(No),
(Yes, >0.10),
(Yes, 0.10)
(No),
(Yes, 10 deg.),
(Yes, 5 deg.)
(Yes/ No)
(repaired or not repaired)
Sequoyah 2
2-FCV-063-0039-A Safety Injection SIS CCP INJ TANK INLET SHUTOFF VLV 4
Open/Close Yes Low Not Susceptible Yes No(2)
No Yes Repaired(1)
Sequoyah 2
2-FCV-063-0040-B Safety Injection SIS CCP INJ TANK INLET SHUTOFF VLV 4
Open/Close Yes Low Not Susceptible Yes No(2)
No Yes Repaired(1)
Sequoyah 2
2-FCV-063-0072-A Safety Injection CONTAINMENT SUMP FLOW ISOL VLV 18 Open/Close Yes High Not Susceptible Yes No(2)
No Yes Repaired(1)
Sequoyah 2
2-FCV-063-0073-B Safety Injection CONTAINMENT SUMP FLOW ISOL VLV 18 Open/Close Yes High Not Susceptible Yes No(2)
No Yes Repaired(1)
Sequoyah 2
2-FCV-074-0003-A Residual Heat Removal RHR PUMP A-A INLET FLOW CONTROL VLV 14 Open/Close No High Susceptible Yes No(2)
No Yes Not repaired(4)
Sequoyah 2
2-FCV-074-0021-B Residual Heat Removal RHR PUMP B-B INLET FROM CONTROL VLV 14 Open/Close No High Susceptible Yes No(2)
No Yes Not repaired(4)
Sequoyah 2
2-FCV-074-0033-A Residual Heat Removal RHR HT EXCH A BYPASS 8
Open/Close Yes Medium Not Susceptible Yes No(2)
No Yes Repaired(1)
Sequoyah 2
2-FCV-074-0035-B Residual Heat Removal RHR HT EXCH B BYPASS 8
Open/Close Yes Medium Susceptible Yes No(2)
No Yes Not repaired(4)
Summary of Commitments
- 1. TVA will repair the following SQN Unit 1 Anchor Darling double disc gate valve MOVs during the Spring 2018 refueling outage: 1-FCV-063-0022-B, 1-FCV-074-0033-A, and 1-FCV-074-0035-B.
- 2. TVA will repair the following SQN Unit 2 Anchor Darling double disc gate valve MOVs during the Fall 2018 refueling outage: 2-FCV-063-0022-B, 2-FCV-074-0003-A, 2-FCV-074-0021-B, and 2-FCV-074-0035-B.
- 3. By April 30, 2018 TVA will complete its review based on TP16-1-112 R4 of BFN Anchor Darling double disc gate valve MOVs with active safety functions that are susceptible to the condition described in the Flowserve 10CFR21 Update dated July 11, 2017 to determine which valves require repair.
- 4. Upon completion of this review, by May 31, 2018, TVA will provide an updated listing of the BFN Anchor Darling valve information with a repair schedule for each susceptible valve not yet repaired.