ML12335A422
| ML12335A422 | |
| Person / Time | |
|---|---|
| Site: | Indian Point  |
| Issue date: | 12/22/2011 |
| From: | Entergy Nuclear Operations |
| To: | Atomic Safety and Licensing Board Panel |
| SECY RAS | |
| References | |
| RAS 21601, 50-247-LR, 50-286-LR, ASLBP 07-858-03-LR-BD01 | |
| Download: ML12335A422 (12) | |
Text
United States Nuclear Regulatory Commission Official Hearing Exhibit Entergy Nuclear Operations, Inc.
In the Matter of:
(Indian Point Nuclear Generating Units 2 and 3)
RIV000028 lW\ c.\,Vf\REGCI<.q;. ASLBP #: 07-858-03-LR-BD01 Docket #: 05000247 l 05000286 Submitted: December 22, 2011 Exhibit #: RIV000028-00-BD01 Identified: 10/15/2012
< Admitted: 10/15/2012
- o 0
< Withdrawn:
- 'Y f?j
~...",'7 . ~J' Rejected: Stricken:
- ... Other:
I Entergy I CONDITION REPORT ICR-IP2-2001-10525 I Originator: MALONE, HAZEL Originator Phone: 0 Originator Site Group: IP2 ENG P&C-Code. Programs Staff Operability Required: Y Supervisor Name: SCHWARTZ, GEOFFREY Reportability Required: N Discovered Date: 10/31 /200100:00 Initiated Date: 10/31 /200100:00 Condition
Description:
CR Date: 10/31/2001 12:33 CR Entered Date: 10/3112001 14:21 UT inspections were performed on sections of Crossunder piping as the result of a pinhole leak found on the MSR2IA inlet piping during the cycle (see CR# 200103681). Areas on the expansion joints and piping upstream ofMSR21A show measured thickness below or close to allowable minimum waIl (0.247") based on UT results taken during the mid-cycle outage. The cause of these thinned areas is believed to be Flow Accelerated Corrosion (FAC). It is recommended that these areas be repaired at this time. Design Engineering has been notified and temporary repair of thinned areas are being performed. See drawings attached for location of thinned area and the mearsured thickness readings of these areas.
Immediate Action
Description:
Evaluated thinned areas and worked with Design Engineering to develop temporary repair for degraded areas.
Suggested Action
Description:
EQUIPMENT:
Tag Name Tag Suffix Name Component Code Process System Code 21AMSR MS REFERENCE ITEMS:
Type Code Item Desc CR 200103681 CR 200103681 CR 200110521 CR 200110526 DETECTION SI LOCATION Turbine WON 01-23886 WON 01-23886 Y WON 01-24370 WON 01-24370 Y TRENDING (For Reference Purposes Only):
Trend Type Trend Code PR PR-CORROSION & EROSION (ALL W ALL-THINNING PROCESSE OR OR-DESIGN ENGINEERING EQ EQ-AH KA KA-IN IPEC00092616
Entergy I CORRECTIVE ACTION 1 CR-IP2-2001-10525 CANumber:
Site Group Name Assigned By: IP2 CA&AStaff E-CAPT AIN, CRS Assigned To: IP2 ENG P&C-Code Programs Mgmt Azevedo,Nelson F Subassigned To: IP2 ENG P&C-Code Programs Staff MALONE, HAZEL Originated By: E-CAPTAIN, CRS 11 /1/2001 00:00:00 Performed By: Azevedo,Nelson F 11 /291200100:00:00 Subperformed By: MALONE, HAZEL 11126/2001 00:00:00 Approved By:
Closed By: E-CAPT AIN, CRS 11129/2001 00:00:00 Current Due Date: 12/0112001 Initial Due Date: 12/0112001 CA Type: DISP - CORR ACTION Plant Constraint: NONE CA
Description:
Please evaluate to determine apparent cause and recommend corrective actions. (cbh)
CA REFERENCE ITEMS:
Type Code Description CRSID 254719
Response
IPEC00092617
Entergy I CORRECTIVE ACTION ICR-IP2-2001-10525 Subresponse :
11 /09/2001 Assigned to: MALONE, HAZEL Status: Closed + Approved Action Requsted: Hazel, please evaluate this SL2 and provide corrective actions ;;tSrequired. Nelson Assignee Response: See SL Report Reviewer Comment:
Although this CR was classified as an SL2, the wall thinning detected during the mid-cycle inspection was a result of Flow Accelerated Corrosion (F AC) which is a well understood degradation mechanism and it is well modeled in industry and in IP2 F AC analysis. No causal factors or any other evaluation was perfformed on this CR because it was considered provide no additional value to this already, well understood phenomena. Based on this, it is requested that this CR be dovmgraded to an SL3 and closed as such.
Nelson Azevedo 11 /29101 Significance Level 3 Report UT inspections were performed on the 26.5" ID vertical *riser section of crossunder piping leading to MSR21A as the result of a pinhole leak which occurred in this section during the cycle (See CR# 200103681). Results of the UTinspections performed found an additional thinned area on the same expansion joint containing the pinhole leak and a thinned area on a pup piece adjacent to that expansion joint (See attachment for locations of thinned areas). The thinned areas found measured below or close to allowable minimum wall thickness (See wear rate/structural evaluation for each component inspected for details).
Cause of wear is believed to be the result of Flow Accelerated Corrosion (FAC). FAC is the process whereby the protective oxide layer on carbon steel piping is dissolved by flowing water or wet steam which results in the wearing away of the underlying metal. Main Steam exhausted from the High Pressure Turbine enters the Crossunder piping as a wet steam, that can contain as much as 20% moisture. This wet steam mixture combined with the high fluid velocity and high temperature of this piping system can result in extremely high wear rates and establishes Crossunder piping as one of the most susceptible systems to F AC. Though the IP2 F AC program history shows that all crossunder piping was completely weld overlaid with Stainless Steel to prevent wear, certain areas near expansion joints were not weld overlaid due to restrictions on welding near the expansion joints links (dogbones). Certain areas near these expansion joint dogbones may have been consequently left as Carbon Steel due to these restrictions and are still vulnerable to the effects of FAC. The leak that occurred during the cycle 15, as well as the thinned areas found during the mid-cycle outage were all located in the vicinity of the expansion joints.
Thinned areas located during the mid cycle inspection will be temporarily repaired externally per WO# 01-23886 until they can be visually inspected internally during the 2002 refueling outage and permanently repaired. Internal inspections are recommended to determine the location of the expansion dogbones and also to locate areas not weld overlayed that may need repair. Internal inspections of crossunder piping will be added to the scope of the 2002 refueling outage as part of the FAC outage inspection scope (see FAC Master Inspection List for details) and may include inspection of parallel trains or similar expansion joint areas.
Permanent repair of thinned areas will be performed under work order 01-24370. Methods of permanent repair as well as expansion joint replacement options should be researched and planned for accordingly prior to the outage to ensure proper scheduling.
Thinned areas located during the mid cycle inspection will be temporarily repaired externally per WO# 01-23886 until they can be visually inspected internally during the 2002 refueling outage and permanently repaired. Internal inspections are recommended to determine the location of the --- see attachment for rest ---
Closure Comments:
reject per CAG quality review Attachments:
Subresp Description 11109/2001 Assigned to: MA IPEC00092618
Entergy I CORRECTIVE ACTION 1 CR-IP2-2001-10525 CANumber: 2 Site H, ________--.,;;G;,;;.ro.;;,;u;;,!p'--_ _ _ _ _ _-' _ _ _...;N;.;;a;::m::e::...._---1 Assigned By: IP2 CA&AStaff E-CAPT AIN, CRS Assigned To: IP2 ENG P&C-Code Programs Mgmt Azevedo,Nelson F Subassigned To :
Originated By: E-CAPTAIN, CRS 12/4/2001 00 :00:00 Performed By: Azevedo,NeisoD F 12/4/2001 00:00:00 SubperformedBy:
Approved By:
Closed By: Azevedo,NelsoD F 12/4/200100:00:00 Current Due Date: 12/06/2001 Initial Due Date: 12/06/2001 CA Type: DISP - CORR ACTION Plant Constraint: NONE CA
Description:
reject per CAG quality review Downgraded from SL2 to SL3 per Joe Barlok. Due date changed to 12/6/01...12/4/01 MK CA REFERENCE ITEMS:
Type Code Description CRSID 260983 IPEC00092619
Entergy I CORRECTIVE ACTION ICR-IP2-2001-10525
Response
Significance Level 3 Report UT inspections were performed on the 26.5" ID vertical riser section of crossunder piping leading to MSR2l A as the result of a pinhole leak which occurred in this section during the cycle (See CR# 200103681). Results of the UT inspections performed found an additional thinned area on the same expansion joint containing the pinhole leak and a thinned area on a pup piece adjacent to that expansioujoint (See attachment for locations of thinned areas). The thinned areas found measured below or close to allowable minimum wall thickness (See wear rateistructural evaluation for each component inspected for details). ' .
Cause of wear is believed to be the result of Flow Accelerated Corrosion (F AC). F Ac: is the process whereby the protective oxide layer on carbon steel piping is dissolved by flowing water or wet steam which results in the wearing away of the underlying metal. Main Steam exhausted from the High Pressure Turbine enters the Crossunder piping as a wet steam, that can contain as much as 20% moisture. This wet steam mixture combined with the high fluid velocity and high temperature of this piping system can result in extremely high wear rates and establishes Crossunder piping as one of the most susceptible systems to F AC. Though the lP2 F AC program history shows that all crossunder piping was completely weld overlaid with Stainless Steel to prevent wear, certain areas near expansion joints were not weld overlaid due to restrictions on welding near the expansion joints links (dogbones). Certain areas near these expansion joint dogbones may have been consequently left as Carbon Steel due to these restrictions and are stifl vulnerable to the effects of F AC. The leak that occurred during the cycle 15, as well as the thinned areas found during the mid-cycle outage were all located in the vicinity of the expansion joints.
Thinned areas located during the mid cycle inspection will be temporarily repaired externally per WO# 01-23886 until they can be visually inspected internally during the 2002 refueling outage and permanently repaired. Internal inspections are recommended to determine the 'location of the expansion dogbones and also to locate areas not weld overlayed that may need repair. Internal inspections of crossunder piping will be added to the scope of the 2002 refueling outage as part of the FAC outage inspection scope (see FAC Master Inspection List for details) and may include inspection of parallel trains or similar expansion joint areas.
Permanent repair of thinned areas will be performed under work order 01-24370. Methods of permanent repair as well as expansion joint replacement options should be researched and planned for accordingly prior to the outage to ensure proper scheduling. '
Thinned areas located during the mid cycle inspection wiUbe temporarily repaired externally per WO# 01-23886 until they can be visually inspected internally during the 2002 refueling outage and permanently repaired. Internal inspections are recommended to determine the location of the expansion dogbones and also to locate areas not weld overlayed that may need repair. Internal inspections of crossunder piping will be added to the scope of the 2002 refueling outage aspart of the FAC outage inspection scope (see FAC Master Inspection List for details) and may include inspection of parallel trains or similar expansion joint areas.
Permanent repair of thinned areas will be performed under work order 01-24370 . Methods of permanent repair as well as expansion joint replacement options should be researched and planned for accordingly prior to the outage to ensure proper scheduling. '
Sutiresponse :
Closure Comments:
N /A IPEC00092620
Entergy I CORRECTIVE ACTION ICR-IP2-2001-10525 CANumber: 3
__~Si~re~ _______________G~ro~u~p~____________~1 ____~N~a~m~e____~1 Assigned By: IP2 CA&A Staff E-CAPTAlN, CRS Assigned To: IP2 ENG SYS-Balance of Plant Staff Ray,Bryan J Subassigned To:
Originated By: E-CAPT AlN, CRS 1111 /200100:00:00 Performed By: Ray,Bryan J 111312001 00:00:00 Subperformed By:
Approved By:
Closed By: Ray,Bryan J 1113/200 I 00:00:00 Current Due Date: 11108/2001 Initial Due Date: 11/08 /2001 CA Type: CRS - FYI Plant Constraint: NONE CA
Description:
For your infonnation on equipment with your system.
CA REFERENCE ITEMS:
Type Code Description CRSID 254720
Response
Subresponse :
Closure Comments:
NlA IPEC00092621
Entergy I CORRECTIVE ACTION ICR-IP2-2001-10525 CANumber: 4 Site Group Name Assigned By: IP2 CA&AStaff E-CAPTAIN, CRS Assigned To: IP2 ENG P&C-Code Programs Mgmt Azevedo,Nelson F Subassigned To :
Originated By: E-CAPTAIN, CRS 12/4/2001 00:00 :00 Performed By: Azevedo,Neison F 2IV200200:00:00 Subperformed By:
Approved By:
Closed By: Azevedo,Nelson F 2/1 /2002 00:00:00 Current Due Date: 02/17/2002 Initial Due Date: 02/ 17/2002 CA Type: CR CLOSURE REVIEW Plant Constraint: NONE CA
Description:
Follow up on corrective action assignments CA REFERENCE ITEMS:
Type Code Description CRSID , 261193
Response
Since the corresponding ICAs have been adequately implemented, this CR is ready for closure.
Sub response :
Closure Comments:
N/A IPEC00092622
Entergy I CORRECTIVE ACTION 1 CR-IP2-2001-10525 CANumber: 5 Site Group Name Assigned By: IP2 ENGP&C-Code Programs Mgmt Azevedo,Nelson F Assigned To: IP2 ENG P&C-Code Programs Staff MALONE, HAZEL Subassigned To :
Originated By: Azevedo,NeJson F 12/412001 00:00:00 Performed By: MALONE, HAZEL 1/18/200200:00:00 Subperformed By:
Approved By:
Closed By: Azevedo,Nelson F 1/18/200200:00:00
(
Current Due Date: 01118/2002 Initial Due Date: 0111812002 CA Type: PERFORM CA Plant Constraint: NONE CA
Description:
Add internal inspection ofMSR vertical risers to FAC Master Inspection List (MIL) for 2002 refueling outage.
CA REFERENCE ITEMS:
Type Code Description CRS CLASS CRS ID 261191
Response
Intemaiinspection of21A&B, 22A&B and 23A&B MSR vertical risers will be added to FAC Master Inspection List (MIL) for 2002 refueling outage. Final MIL is due for release 113112002 Subresponse :
Closure Comments:
Please reflect the fact that the inspection locations have been added to the inspection list even though the final list will not be issued until 1131102.
IPEC00092623
Entergy I CORRECTIVE ACTION 1 CR-IP2-2001-10525 CA Number: 6 Site Group Name Assigned By: IP2 ENG P&C-Code Programs Mgmt Azevedo,Nelson F Assigned To: IP2 ENG P&C-Code Programs Staff Ml\LONE, HAZEL Subassigned To :
Originated By: Azevedo,Nelson F 12/4/2001 00:00:00 Performed By: MALONE, HAZEL 1118/200200:00:00 Subperformed By:
Approved By:
Closed By: Azevedo,Nelson F 1/18/2002 00:00:00 Current Due Date: 01 / 18/2002 Initial Due Date: 01 /18/2002 CA Type: PERFORM CA Plant Constraint: NONE CA
Description:
Research methods of permanent repairs tor previously temporary repaired areas of crossunder piping. Also, research the cost
.and resource information for the replacement of crossunder expansion joints to determine if this option is practicable.
CA REFERENCE ITEMS:
Type Code Description CRSCLASS CRSID 261192 IPEC00092624
. .. Entergy CORRECTIVE ACTION I CR-IP2-20()l-10525
... ~----------~~--~------------------------------~----------------~
,.. Response:
There have been many different methods used to permanently repair these areas of crossunder piping. The following are descriptions of these methods:
- 1. Welding under expansion dogbones One option of repair that has been performed at plants such as Surry is to remove the expansion dogbones, perform Stainless steel cladding to expose piping underneath and replace dogbones. Advantages to this repair method are that the entire area would be protected (including area under dogbones) and thinned areas of piping can be brought back up to nominal thickness by the overlay. Disadvantages to this repair is that it is not a recommended repair method of Westinghouse because it may jeopardize the flexibility of the expansion joint and that extra time will be needed to perform the engineering to analyze this concern.
- 2. Stainless Steel Tubing Repair This repair option was used at St. Lucie Unit 1 & 2 to repair eroded area under dog bones. A stainless steel piece of tubing was placed next to the dogbones and welded in place. The tubing was then deformed to ensure a secure fit up to the dogbone (see attachment for details). Advantages to this repair are that there' is no welding to the dogbone and no arc strikes on the dogbone as recommended by Westinghouse. Disadvantage to this repair is that if there is not a consistent bond between the tubing and the dogbone, steam can still get into that area and erode the piping underneath.
- 3. Stainless Steel Covering over dogbones During the last CHECWORKs Users Group (CHUG) meeting (January 14&15,2002), itwas mentioned the Point Beach has welded stainless steel covers over the dogbones in their crossunder piping. At this time, Point Beach FAC engineer has provided no additional information.
- 4. Welding on Outside of crossunder piping A 1995 letter to Westinghouse on the subject of repairing eroded areas of crossunder piping from the outside yield the following response:
These eroded areas beneath the expansion joint link (dogbones) can be repaired from the outside of the pipe. The eroded area beneath the link should be ground out and weld repaired using 309 stainless as per PS 600374 for the first few passes to provide an erosion resistant inner surface. The remaining cavity should be built-up with carbon steel weld material as per PS 600945 Part 1-1-1-8. Post weld heat treatment should not be performed for any of the above welding processes.
The expansion joint link should not be subjected to any arc strikes during the welding process. It is recommended that a copper backing plate be placed between the link and the area of repair to protect the link during welding.
A carbon steel backing plate can be welded over the repaired area on the outside diameter of the pipe, if desired. This welding should be performed to PS 600945 1-1-1-8. No PWHT is to be performed.
Advantages of this repair are that it is a recommended repair from the expansion joint vendor (Westinghouse) and that it would restore original pipe thickness. Would need to obtain welding procedure from Westinghouse if similar procedure is not available.
Replacement of Expansion Joint sections (21A & 218 Vertical Risers) was also investigated for this RES. At the time of this response, Westinghouse (Siemens) had not replied with an estimate for replacing both 21A and 218 vertical risers. The following information was provided from proposals of IP3 ) 997 Crossunder replacement of their 31 A and 31 B vertical risers and IP2 1995 Crossunder replacement of 32"expansion joints under the HP turbine.
IP2 32" Expansion Joints under HP Turbine (1995) o Material cost - $24,160 (8, 32" Plates of 1-114 Chrome) o Heat Treatment of32" Expansion Joints - $17,086.76 (15 days to perform)
IP3 31 A & 31 B Vertical Riser Replacement (1997) o Lump sum quote for design/engineering of all MSR vertical risers and --- see attachment for rest ---
Subresponse :
Closure Comments:
Ni A IPEC00092625
Entergy I CORRECTIVE ACTION ICR-IP2-2001-10525 Attachments:
Resp Description There have been many different IPEC00092626
Entergy I CORRECTIVE ACTION ICR-IP2-2001-10525 CANumber: 7 Site Group Name I Assigned By: IP2 ENG P&C-Code Programs Mgmt Azevedo,Nelson F Assigned To: IP2 ENG P&C-Code Programs Statl' MALONE, HAZEL Subassigned To:
Originated By: Azevedo,Nelson F 1118/200200:00:00 Performed' By: MALONE, HAZEL 1118/200200:00:00 Sub performed By:
Approved By:
Closed By: Azevedo,Nelson F 1118/200200:00:00 Current Due Date: ' 01118/2002 Initial Due Date: 01118/2002 CA Type: PERFORM CA Plant Constraint: NONE CA
Description:
Please reflect the fact that the inspection locations have been added to the inspection Jist even though the final list will not be issued until 1/31/02.
CA REFERENCE ITEMS:
Type Code Description CRS CLASS I CRSID 270378
Response
Internal inspections of21A&B, 22A&B and 23A&B MSR vertical risers have been added to FAC Master Inspection List (MIL) for the 2002 refueling outage. The final MIL is due for release 1/3112002 Subresponse :
Closure Comments:
N /A IPEC00092627