RNP-RA/12-0101, Relief Request (RR)-7 from Immediate ASME Code Repair of Refueling Water Storage Tank Drain Value (SI-837) for Fifth Ten-year Inservice Inspection Program Plan: Difference between revisions
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{{#Wiki_filter:Progress Energy 10 Serial: RNP-RA/12-0101 OCT 0 5 2012 Attn: Document Control Desk United States Nuclear Regulatory Commission Washington, DC 20555-0001 H. B. ROBINSON STEAM ELECTRIC PLANT, UNIT NO. 2 DOCKET NO. 50-26 1/RENEWED LICENSE NO. DPR-23 RELIEF REQUEST (RR)-07 FROM IMMEDIATE ASME CODE REPAIR OF REFUELING WATER STORAGE TANK DRAIN VALVE (SI-837)FOR FIFTH TEN-YEAR INSERVICE INSPECTION PROGRAM PLAN Ladies and Gentlemen: | {{#Wiki_filter:Progress Energy 10 Serial: RNP-RA/12-0101 OCT 0 5 2012 Attn: Document Control Desk United States Nuclear Regulatory Commission Washington, DC 20555-0001 H. B. ROBINSON STEAM ELECTRIC PLANT, UNIT NO. 2 DOCKET NO. 50-26 1/RENEWED LICENSE NO. DPR-23 RELIEF REQUEST (RR)-07 FROM IMMEDIATE ASME CODE REPAIR OF REFUELING WATER STORAGE TANK DRAIN VALVE (SI-837) | ||
Pursuant to 10 CFR 50.55a(a)(3)(ii), Carolina Power and Light (CP&L) Company, now doing business as Progress Energy, requests relief from the 2007 Edition, through the 2008 Addenda, of the ASME Section XI Code requirement as stipulated in Paragraph IWC-3122.2 on the basis that compliance with the specified requirements would result in a hardship or unusual difficulty without a compensating increase in the level of quality and safety. Accordingly, please find Relief Request (RR)-07 enclosed. | FOR FIFTH TEN-YEAR INSERVICE INSPECTION PROGRAM PLAN Ladies and Gentlemen: | ||
This relief request is being submitted because a through-wall flaw was discovered in the body of a Refueling Water Storage Tank (RWST) 6-inch cast stainless steel drain valve located outside in the plant yard on September 7, 2012. A subsequent inspection of RWST drain line piping and fixtures did not identify any additional through-wall leakage in similar piping and valves.This flaw was not found during performance of an ASME Section XI Code inservice inspection; therefore, Section XI requirements do not technically apply until Code Repair/Replacement activities are conducted to correct the flaw. However, using conservative decision making and for flaw evaluation review expediency, Progress Energy is pursuing NRC acceptance of our position through the formal relief request process.Progress Energy plans to install a leak limiting clamping device within 45 days of receipt of the requested relief. This will help ensure that the through wall flaw does not degrade to a condition requiring more intrusive compensatory measures or plant shutdown prior to the next refueling outage scheduled for September 2013.Progress Energy Carolinas, Inc.Robinson Nuclear Plant 3581 West Entrance Road Hartsville, SC 29550 I.. | Pursuant to 10 CFR 50.55a(a)(3)(ii), Carolina Power and Light (CP&L) Company, now doing business as Progress Energy, requests relief from the 2007 Edition, through the 2008 Addenda, of the ASME Section XI Code requirement as stipulated in Paragraph IWC-3122.2 on the basis that compliance with the specified requirements would result in a hardship or unusual difficulty without a compensating increase in the level of quality and safety. Accordingly, please find Relief Request (RR)-07 enclosed. This relief request is being submitted because a through-wall flaw was discovered in the body of a Refueling Water Storage Tank (RWST) 6-inch cast stainless steel drain valve located outside in the plant yard on September 7, 2012. A subsequent inspection of RWST drain line piping and fixtures did not identify any additional through-wall leakage in similar piping and valves. | ||
This flaw was not found during performance of an ASME Section XI Code inservice inspection; therefore, Section XI requirements do not technically apply until Code Repair/Replacement activities are conducted to correct the flaw. However, using conservative decision making and for flaw evaluation review expediency, Progress Energy is pursuing NRC acceptance of our position through the formal relief request process. | |||
Progress Energy plans to install a leak limiting clamping device within 45 days of receipt of the requested relief. This will help ensure that the through wall flaw does not degrade to a condition requiring more intrusive compensatory measures or plant shutdown prior to the next refueling outage scheduled for September 2013. | |||
Progress Energy Carolinas, Inc. | |||
Robinson Nuclear Plant 3581 West Entrance Road Hartsville, SC 29550 | |||
' . I.. | |||
United States Nuclear Regulatory Commission Serial: RNP-RA/12-0101 Page 2 of 3 This letter contains the following Regulatory Commitments: | |||
: 1. The valve will be shielded from environmental elements with access for inspection until a Code Repair/Replacement. | : 1. The valve will be shielded from environmental elements with access for inspection until a Code Repair/Replacement. | ||
: 2. Until installation of a clamp or until a Code Repair/Replacement is performed: | : 2. Until installation of a clamp or until a Code Repair/Replacement is performed: | ||
: a. Operations personnel will visually monitor the leak each shift with results entered into AUTOLOG. A crack length greater than 1 inch or a leakage increase greater than 16 drops/minute will require station management attention and entered into the Corrective Action Program for appropriate evaluation and further actions.b. NDE personnel will perform ultrasonic volumetric examination of the flaw location every 90 days. A crack length greater than 7 inches will require station management attention and entered into the Corrective Action Program for appropriate evaluation and further actions.3. Following installation of a clamp: a. A system leakage test at normal operating pressure and normal operating temperature and a VT-2 examination in accordance with IWA-5000 will be performed on the portion of line number 6-SI-151 R- 141 containing the clamp.b. The area around the clamped valve will be monitored for leakage on a weekly basis in accordance with Article IX-6000 (c) with a record entered into AUTOLOG and with an entry made into the Corrective Action Program for appropriate evaluation and disposition in the event leakage is observed.4. An ASME Section XI Code Repair/Replacement shall be performed during the next scheduled refueling outage, RO-28, which is currently scheduled to begin September 2013. If a condition leads to a forced outage of sufficient duration and scope to allow a Code Repair/Replacement, the repair will be performed during this forced outage.Any other actions discussed in this letter should be considered intended or planned actions. They are included for informational purposes but are not considered Regulatory Commitments. | : a. Operations personnel will visually monitor the leak each shift with results entered into AUTOLOG. A crack length greater than 1 inch or a leakage increase greater than 16 drops/minute will require station management attention and entered into the Corrective Action Program for appropriate evaluation and further actions. | ||
United States Nuclear Regulatory Commission Serial: RNP-RA/12-0101 Page 3 of 3 If you have any questions concerning this matter, please contact Mr. Richard Hightower, Supervisor | : b. NDE personnel will perform ultrasonic volumetric examination of the flaw location every 90 days. A crack length greater than 7 inches will require station management attention and entered into the Corrective Action Program for appropriate evaluation and further actions. | ||
-Licensing/Regulatory Programs at (843) 857-1329.Sincerely, Sharon A. Wheeler Manager -Support Services -Nuclear SAW/sjg | : 3. Following installation of a clamp: | ||
: a. A system leakage test at normal operating pressure and normal operating temperature and a VT-2 examination in accordance with IWA-5000 will be performed on the portion of line number 6-SI-151 R- 141 containing the clamp. | |||
: b. The area around the clamped valve will be monitored for leakage on a weekly basis in accordance with Article IX-6000 (c) with a record entered into AUTOLOG and with an entry made into the Corrective Action Program for appropriate evaluation and disposition in the event leakage is observed. | |||
: 4. An ASME Section XI Code Repair/Replacement shall be performed during the next scheduled refueling outage, RO-28, which is currently scheduled to begin September 2013. If a condition leads to a forced outage of sufficient duration and scope to allow a Code Repair/Replacement, the repair will be performed during this forced outage. | |||
Any other actions discussed in this letter should be considered intended or planned actions. They are included for informational purposes but are not considered Regulatory Commitments. | |||
United States Nuclear Regulatory Commission Serial: RNP-RA/12-0101 Page 3 of 3 If you have any questions concerning this matter, please contact Mr. Richard Hightower, Supervisor - Licensing/Regulatory Programs at (843) 857-1329. | |||
Sincerely, Sharon A. Wheeler Manager - Support Services - Nuclear SAW/sjg | |||
==Enclosure:== | ==Enclosure:== | ||
c: Mr. V. M. McCree, NRC, Region II Ms. A. T. Billoch-Colon, NRC Project Manager, NRR Ms. F. E. Saba, NRC Project Manager, NRR NRC Resident Inspector, HBRSEP Unit No. 2 United States Nuclear Regulatory Commission Enclosure to Serial: RNP-RA/12-0101 ENCLOSURE Fifth Ten-Year Interval Inservice inspection Program Plan Relief Request Number RR-07 Safety Injection Valve SI-837 RR-07 7 pages | c: Mr. V. M. McCree, NRC, Region II Ms. A. T. Billoch-Colon, NRC Project Manager, NRR Ms. F. E. Saba, NRC Project Manager, NRR NRC Resident Inspector, HBRSEP Unit No. 2 | ||
-- Compliance with the Specified Requirements of this Section Would Result in a Hardship or Unusual Difficulty without a Compensating Increase in the Level of Quality and Safety --ASME Code Comoonent(s) | |||
Affected The affected ASME Code component is identified as Safety Injection system valve SI-837 and is a Class 2, 150 pound, manually-operated, 6-inch cast stainless steel, wedge, gate valve manufactured by Crane Co. The valve body is made of SA351, CF8M cast stainless steel material.The SI-837 valve is an isolation valve within the Refueling Water Storage Tank (RWST) drain line, line number 6-SI-151R-141. | United States Nuclear Regulatory Commission Enclosure to Serial: RNP-RA/12-0101 ENCLOSURE Fifth Ten-Year Interval Inservice inspection Program Plan Relief Request Number RR-07 Safety Injection Valve SI-837 RR-07 7 pages to RR-07 5 pages | ||
The valve is horizontally orientated approximately two feet from the connection of the line to the RWST tank and is subject to a pressure of approximately 15 psi (the static head of the RWST tank). The drain line connects to the RWST tank approximately one foot above the base of the tank on the upstream side of the valve and is capped approximately three feet downstream of valve. The maximum operating temperature of the valve and line number 6-SI-151 R-141 is bounded by the operating temperature of the RWST which is 100'F. The line is normally maintained in a static condition due to the single connection to the RWST and insulated with a sheet metal exterior containing silicon/aluminum oxide/carbonate insulation. | |||
The insulation has been removed at the valve extending beyond the valve weld ends.SI-837 is located in an outdoor environment next to the RWST, and is exposed to seasonal temperatures and precipitation. | 1,. ! | ||
SI-837 is a manual valve, model number L61174AM manufactured by Crane Valve Company. Model L61174AM is used in the Safety Injection system only within the RWST drain line application. | H. B. Robinson Steam Electric Plant, Unit No. 2 Fifth Ten-Year Interval Relief Request RR-07 Relief Request Number RR-07 Safety Injection Valve SI-837 Relief Requested In Accordance with 10 CFR 50.55a (a)(3)(ii) | ||
To determine the extent of condition, a walk down was performed of the RWST, piping and valves located outdoors within the vicinity of the RWST.The walk down was focused on identifying any other leaks as indicated by the buildup of boric acid crystals on the exterior to the insulation. | -- Compliance with the Specified Requirements of this Section Would Result in a Hardship or Unusual Difficulty without a Compensating Increase in the Level of Quality and Safety -- | ||
No additional evidence of boric acid residue was noted.1 of 7 H. B. Robinson Steam Electric Plant, Unit No. 2 Fifth Ten-Year Interval Relief Request RR-07 Valve SI-837 provides system boundary isolation for the RWST and is normally closed and locked. The welded cap on the end of line number 6-SI-1 51 R-141 provides a permanent secondary system boundary.Containment boundary is maintained through various isolation valves of various systems that penetrate the containment structure. | ASME Code Comoonent(s) Affected The affected ASME Code component is identified as Safety Injection system valve SI-837 and is a Class 2, 150 pound, manually-operated, 6-inch cast stainless steel, wedge, gate valve manufactured by Crane Co. The valve body is made of SA351, CF8M cast stainless steel material. | ||
The Safety Injection (SI)system is one such system that has various components inside and outside the containment structure. | The SI-837 valve is an isolation valve within the Refueling Water Storage Tank (RWST) drain line, line number 6-SI-151R-141. The valve is horizontally orientated approximately two feet from the connection of the line to the RWST tank and is subject to a pressure of approximately 15 psi (the static head of the RWST tank). The drain line connects to the RWST tank approximately one foot above the base of the tank on the upstream side of the valve and is capped approximately three feet downstream of valve. The maximum operating temperature of the valve and line number 6-SI-151 R-141 is bounded by the operating temperature of the RWST which is 100'F. The line is normally maintained in a static condition due to the single connection to the RWST and insulated with a sheet metal exterior containing silicon/aluminum oxide/carbonate insulation. The insulation has been removed at the valve extending beyond the valve weld ends. | ||
The RWST tank is located outside the containment structure and is the source of borated water for the Emergency Core Cooling systems (ECCS) and Containment Spray (CS) systems during and post design basis events. The RWST tank is vented to the atmosphere. | SI-837 is located in an outdoor environment next to the RWST, and is exposed to seasonal temperatures and precipitation. SI-837 is a manual valve, model number L61174AM manufactured by Crane Valve Company. Model L61174AM is used in the Safety Injection system only within the RWST drain line application. To determine the extent of condition, a walk down was performed of the RWST, piping and valves located outdoors within the vicinity of the RWST. | ||
Containment boundary is provided with redundant isolation provisions to assure that no unrestricted release of radioactivity to the environment will occur. This action is provided by normally open valves SI-864A & SI-864B. The containment boundary is established by the closure of valves SI-864A & SI-864B. Valve SI-837 valve is not a containment isolation valve, and does not provide a containment boundary function.A2olicable Code Edition and Addenda Robinson Nuclear Plant entered the Fifth, 10-year ISI Inspection Interval effective July 21, 2012. The ASME Section XI Code applicable to the Fifth 10-year interval is the 2007 Edition through the 2008 Addenda.Aoolicable Code Reauirement ASME Section X1 Code, subsection IWC, "Requirements for Class 2 Components of Light-Water Cooled Power Plants", subparagraph IWC-3122.2,"Acceptance by Repair/Replacement Activity". | The walk down was focused on identifying any other leaks as indicated by the buildup of boric acid crystals on the exterior to the insulation. No additional evidence of boric acid residue was noted. | ||
Reason for Reauest Active leakage from a small circumferential flaw on the upstream side of the valve body of valve SI-837 at the transition between the valve pipe run and the valve neck was identified following investigation of boric acid deposits on the exterior of the insulation of line number 6-SI-151R-141. | 1 of 7 | ||
The flaw visually appears to be approximately 1/2" in length. The leakage was quantified at about one (1) drop every five (5) minutes and is estimated to be about 0.25 gallons per week. No change in the leak rate has been observed since initial discovery and quantification of the leak rate. The current leak rate does not challenge the RWST inventory make-up capabilities. | |||
2 of 7 H. B. Robinson Steam Electric Plant, Unit No. 2 Fifth Ten-Year Interval Relief Request RR-07 A catastrophic failure of valve SI-837 would drain the contents of the RWST tank onto the ground on the north side of the auxiliary building with an initial leakage rate of about 60 gallons per second. The grade in the area of the RWST would flow the water toward a catch basin. There are limited restrictions to the flow to the catch basin such that there is sufficient open area around the RWST tank to allow flow away from the auxiliary building. | H. B. Robinson Steam Electric Plant, Unit No. 2 Fifth Ten-Year Interval Relief Request RR-07 Valve SI-837 provides system boundary isolation for the RWST and is normally closed and locked. The welded cap on the end of line number 6-SI-1 51 R-141 provides a permanent secondary system boundary. | ||
The auxiliary building door closest to valve SI-837 is not water tight however if a catastrophic failure were to occur there is a weir just inside the door that would prevent any significant water intrusion into the building. | Containment boundary is maintained through various isolation valves of various systems that penetrate the containment structure. The Safety Injection (SI) system is one such system that has various components inside and outside the containment structure. The RWST tank is located outside the containment structure and is the source of borated water for the Emergency Core Cooling systems (ECCS) and Containment Spray (CS) systems during and post design basis events. The RWST tank is vented to the atmosphere. Containment boundary is provided with redundant isolation provisions to assure that no unrestricted release of radioactivity to the environment will occur. This action is provided by normally open valves SI-864A & SI-864B. The containment boundary is established by the closure of valves SI-864A & SI-864B. Valve SI-837 valve is not a containment isolation valve, and does not provide a containment boundary function. | ||
Equipment in the area is elevated such that a localized flood would not have any impact.A Code Repair/Replacement of the valve will require entry of the unit into either Mode 5 (cold shutdown) or Mode 6 (refueling) where the RWST is not required to be operable. | A2olicable Code Edition and Addenda Robinson Nuclear Plant entered the Fifth, 10-year ISI Inspection Interval effective July 21, 2012. The ASME Section XI Code applicable to the Fifth 10-year interval is the 2007 Edition through the 2008 Addenda. | ||
The unit is currently operating in Mode 1. Installation of a clamp on the body of valve SI-837 would constitute a non-Code repair.Performing a Code Repair/Replacement activity at this time to correct a flaw that has such a minor leak rate (approximately 1 drop every 5 minutes) would create a hardship based on the potential risks associated with unit cycling and emergent equipment issues incurred during shutdown and startup evolutions. | Aoolicable Code Reauirement ASME Section X1 Code, subsection IWC, "Requirements for Class 2 Components of Light-Water Cooled Power Plants", subparagraph IWC-3122.2, "Acceptance by Repair/Replacement Activity". | ||
No compensating increase in the level of quality and safety would be gained by immediate repair of the flaw.Engineering evaluations and judgment provide a basis to conclude that the SI-837 valve body is capable of performing its design function until the next refueling scheduled for September 2013. Installation of a leak limiting clamping device would provide additional assurance that no significant increase in leak rate through propagation of the existing flaw or catastrophic failure of the valve body could occur.The bases for the conclusion that valve SI-837 is capable of performing its design function until the next refueling outage scheduled for September 2013 include the results of visual and ultrasonic examinations and fracture mechanics analyses. | Reason for Reauest Active leakage from a small circumferential flaw on the upstream side of the valve body of valve SI-837 at the transition between the valve pipe run and the valve neck was identified following investigation of boric acid deposits on the exterior of the insulation of line number 6-SI-151R-141. The flaw visually appears to be approximately 1/2" in length. The leakage was quantified at about one (1) drop every five (5) minutes and is estimated to be about 0.25 gallons per week. No change in the leak rate has been observed since initial discovery and quantification of the leak rate. The current leak rate does not challenge the RWST inventory make-up capabilities. | ||
The activities conducted in performing these examinations and analyses and the results obtained are discussed further below.A visual examination of the flaw and area surrounding the flaw did not indicate that any previous repairs to the casting had been made. Valve SI-837 is part of original plant construction and manufacturing records are not readily available. | 2 of 7 | ||
H. B. Robinson Steam Electric Plant, Unit No. 2 Fifth Ten-Year Interval Relief Request RR-07 A catastrophic failure of valve SI-837 would drain the contents of the RWST tank onto the ground on the north side of the auxiliary building with an initial leakage rate of about 60 gallons per second. The grade in the area of the RWST would flow the water toward a catch basin. There are limited restrictions to the flow to the catch basin such that there is sufficient open area around the RWST tank to allow flow away from the auxiliary building. The auxiliary building door closest to valve SI-837 is not water tight however if a catastrophic failure were to occur there is a weir just inside the door that would prevent any significant water intrusion into the building. Equipment in the area is elevated such that a localized flood would not have any impact. | |||
A Code Repair/Replacement of the valve will require entry of the unit into either Mode 5 (cold shutdown) or Mode 6 (refueling) where the RWST is not required to be operable. The unit is currently operating in Mode 1. Installation of a clamp on the body of valve SI-837 would constitute a non-Code repair. | |||
Performing a Code Repair/Replacement activity at this time to correct a flaw that has such a minor leak rate (approximately 1 drop every 5 minutes) would create a hardship based on the potential risks associated with unit cycling and emergent equipment issues incurred during shutdown and startup evolutions. | |||
No compensating increase in the level of quality and safety would be gained by immediate repair of the flaw. | |||
Engineering evaluations and judgment provide a basis to conclude that the SI-837 valve body is capable of performing its design function until the next refueling scheduled for September 2013. Installation of a leak limiting clamping device would provide additional assurance that no significant increase in leak rate through propagation of the existing flaw or catastrophic failure of the valve body could occur. | |||
The bases for the conclusion that valve SI-837 is capable of performing its design function until the next refueling outage scheduled for September 2013 include the results of visual and ultrasonic examinations and fracture mechanics analyses. The activities conducted in performing these examinations and analyses and the results obtained are discussed further below. | |||
A visual examination of the flaw and area surrounding the flaw did not indicate that any previous repairs to the casting had been made. Valve SI-837 is part of original plant construction and manufacturing records are not readily available. | |||
A digital microscope was used to obtain magnified images of the flaw indication. | A digital microscope was used to obtain magnified images of the flaw indication. | ||
Based on these recorded images, the indication appears to be a relatively tight 3 of 7 H. B. Robinson Steam Electric Plant, Unit No. 2 Fifth Ten-Year Interval Relief Request RR-07 crack with some rust colored areas suggesting corrosion was involved. | Based on these recorded images, the indication appears to be a relatively tight 3 of 7 | ||
In the images, a water droplet is seen forming at one end of the surface crack indication indicating that the through wall flaw does not extend the entire length of surface indication. | |||
Specimen samples of deposits were obtained from the heat tracing, piping, and valve. When analyzed, the samples taken from the valve consisted of boric acid (or a related compound) and an insulation-like material composed of silicon/aluminum oxide /carbonate with a trace amount of chlorine.Based on the digital microscopic examination of the valve, it is believed that the most likely cause of failure is an OD initiated environmentally assisted cracking mechanism such as stress corrosion cracking. | H. B. Robinson Steam Electric Plant, Unit No. 2 Fifth Ten-Year Interval Relief Request RR-07 crack with some rust colored areas suggesting corrosion was involved. In the images, a water droplet is seen forming at one end of the surface crack indication indicating that the through wall flaw does not extend the entire length of surface indication. | ||
Based on the reported thickness of 0.4 inches at the indication location, it is also believed that there is a relatively high probability of a casting defect (e.g. shrinkage porosity) is present at this location.A phased array ultrasonic examination was performed on the cast austenitic stainless steel valve body of valve SI-837 to characterize the leak and adjacent areas on the upstream side of the valve. See Structural Integrity report SI-UT-837-1 for additional information on specific details of the examination and the results.Fracture mechanics analyses were performed using the procedures of IWC-3600 of Section XI of the ASME code for the Robinson Nuclear Plant to evaluate the flaw tolerance of the SI-837 Refueling Water Storage Tank (RWST) valve body containing postulated through-wall flaws.The allowable through-wall circumferential flaw length was determined to be 12.9 inches (without the weight of the leak sealing device included). | Specimen samples of deposits were obtained from the heat tracing, piping, and valve. When analyzed, the samples taken from the valve consisted of boric acid (or a related compound) and an insulation-like material composed of silicon/aluminum oxide /carbonate with a trace amount of chlorine. | ||
The corresponding allowable through-wall flaw length for the axial flaw type is 23.2 inches.UT exams performed by Structural Integrity Associates have estimated the actual flaw length to be approximately 2.5 to 3.5 inches.The calculated allowable planar through-wall flaws are larger than the dimensions of the reported flaw. Therefore, the RWST SI-837 drain valve should be considered operable but degraded until the end of the evaluation period (approximately 15 months).4 of 7 H. B. Robinson Steam Electric Plant, Unit No. 2 Fifth Ten-Year Interval Relief Request RR-07 Prooosed Alternative and Basis for Use Referencing ASME Section XI Code subparagraph IWC-3122.3, "Acceptance by Analytical Evaluation", Progress Energy proposes to temporarily accept the as-found relevant condition (i.e. through-wall flaw) which would allow continued service instead of performing immediate flaw correction by a Code Repair/Replacement activity described in ASME Section XI Code subparagraph IWC-3122.2, "Acceptance by Repair/Replacement Activity". | Based on the digital microscopic examination of the valve, it is believed that the most likely cause of failure is an OD initiated environmentally assisted cracking mechanism such as stress corrosion cracking. Based on the reported thickness of 0.4 inches at the indication location, it is also believed that there is a relatively high probability of a casting defect (e.g. shrinkage porosity) is present at this location. | ||
Referencing ASME Section Xl Code subparagraph IWA-4133, "Mechanical Clamping Devices Used as Piping Pressure Boundary", Progress Energy requests relief from Mandatory Appendix | A phased array ultrasonic examination was performed on the cast austenitic stainless steel valve body of valve SI-837 to characterize the leak and adjacent areas on the upstream side of the valve. See Structural Integrity report SI-UT-837-1 for additional information on specific details of the examination and the results. | ||
Specifically, relief is requested from the limitation of the installation of clamping devices only on the weld ends of valves to allow installation of a clamp on the valve body.Following installation of a clamp that would encompass the entire valve body, volumetric monitoring would not be feasible. | Fracture mechanics analyses were performed using the procedures of IWC-3600 of Section XI of the ASME code for the Robinson Nuclear Plant to evaluate the flaw tolerance of the SI-837 Refueling Water Storage Tank (RWST) valve body containing postulated through-wall flaws. | ||
However, as the flaw is circumferential in nature volumetric monitoring is not required under Mandatory Appendix | The allowable through-wall circumferential flaw length was determined to be 12.9 inches (without the weight of the leak sealing device included). The corresponding allowable through-wall flaw length for the axial flaw type is 23.2 inches. | ||
UT exams performed by Structural Integrity Associates have estimated the actual flaw length to be approximately 2.5 to 3.5 inches. | |||
The calculated allowable planar through-wall flaws are larger than the dimensions of the reported flaw. Therefore, the RWST SI-837 drain valve should be considered operable but degraded until the end of the evaluation period (approximately 15 months). | |||
4 of 7 | |||
H. B. Robinson Steam Electric Plant, Unit No. 2 Fifth Ten-Year Interval Relief Request RR-07 Prooosed Alternative and Basis for Use Referencing ASME Section XI Code subparagraph IWC-3122.3, "Acceptance by Analytical Evaluation", Progress Energy proposes to temporarily accept the as-found relevant condition (i.e. through-wall flaw) which would allow continued service instead of performing immediate flaw correction by a Code Repair/Replacement activity described in ASME Section XI Code subparagraph IWC-3122.2, "Acceptance by Repair/Replacement Activity". | |||
Referencing ASME Section Xl Code subparagraph IWA-4133, "Mechanical Clamping Devices Used as Piping Pressure Boundary", Progress Energy requests relief from Mandatory Appendix IXof ASME Xl, Article IX-1000 (General) paragraph (b) specification of allowable clamp locations. Specifically, relief is requested from the limitation of the installation of clamping devices only on the weld ends of valves to allow installation of a clamp on the valve body. | |||
Following installation of a clamp that would encompass the entire valve body, volumetric monitoring would not be feasible. However, as the flaw is circumferential in nature volumetric monitoring is not required under Mandatory Appendix IXof ASME Xl, Article IX-6000 (a) and (b). The planned clamp installation would constitute a non-Code repair because Article IX-1000 (General) paragraph (b) allows clamp installation on the welded ends of valves but would otherwise comply with all requirements of ASME Section XI Mandatory Appendix IX. | |||
This proposed alternative is based on Progress Energy performing the following actions. | |||
: 1. Completion of a walk down on September 25, 2012 of all piping and valves located outdoors within the vicinity of the RWST with no additional evidence of boric acid crystals on the exterior of piping and valve insulation indicative of a potential leak. | |||
: 2. The valve will be shielded from environmental elements with access for inspection until a Code Repair/Replacement. | |||
: 3. Until installation of a clamp or until a Code Repair/Replacement is performed: | : 3. Until installation of a clamp or until a Code Repair/Replacement is performed: | ||
: a. Operations personnel will visually monitor the leak each shift with results entered into AUTOLOG. A crack length greater than 1 inch or a leakage increase greater than 16 drops/minute will require station management attention and entered into the 5 of 7 H. B. Robinson Steam Electric Plant, Unit No. 2 Fifth Ten-Year Interval Relief Request RR-07 Corrective Action Program for appropriate evaluation and further actions.b. NDE personnel will perform ultrasonic volumetric examination of the flaw location every 90 days. A crack length greater than 7 inches will require station management attention and entered into the Corrective Action Program for appropriate evaluation and further actions.4. Installation of a mechanical clamp complying with the requirements of ASME Section Xl, Appendix IX. All materials will be in accordance with Progress Energy's QA Program for Safety Related material. | : a. Operations personnel will visually monitor the leak each shift with results entered into AUTOLOG. A crack length greater than 1 inch or a leakage increase greater than 16 drops/minute will require station management attention and entered into the 5 of 7 | ||
The sealant and its interface with the class 2 stainless steel piping has been evaluated and is acceptable for use in this application per plant procedures. | |||
: 5. Following installation of a clamp: a. A system leakage test at normal operating pressure and normal operating temperature and a VT-2 examination in accordance with IWA-5000 will be performed on the portion of line number 6-SI-151 R-1 41 containing the clamp.b. The area around the clamped valve will be monitored for leakage on a weekly basis in accordance with Article IX-6000 (c) with a record entered into AUTOLOG and with an entry made into the Corrective Action Program for appropriate evaluation and disposition in the event leakage is observed.6. An ASME Section Xl Code Repair/Replacement shall be performed during the next scheduled refueling outage, RO-28, which is currently scheduled to begin September 2013. If a condition leads to a forced outage of sufficient duration and scope to allow a code Repair/Replacement, the repair will be performed during this forced outage.Duration of Prooosed Alternative The requested relief will be used until an ASME Section XI Code Repair/Replacement activity is performed either during refueling outage RO-28 or during a forced outage of sufficient duration and scope to allow a Code Repair/Replacement activity.6 of 7 H. B. Robinson Steam Electric Plant, Unit No. 2 Fifth Ten-Year Interval Relief Request RR-07 Attachments: | H. B. Robinson Steam Electric Plant, Unit No. 2 Fifth Ten-Year Interval Relief Request RR-07 Corrective Action Program for appropriate evaluation and further actions. | ||
: 1. Structural Integrity Associates Examination Report SI-UT-837-1 for Component SI-837 Refueling Water Storage Tank (RWST) Drain Valve, September 27, 2012 | : b. NDE personnel will perform ultrasonic volumetric examination of the flaw location every 90 days. A crack length greater than 7 inches will require station management attention and entered into the Corrective Action Program for appropriate evaluation and further actions. | ||
: 4. Installation of a mechanical clamp complying with the requirements of ASME Section Xl, Appendix IX.All materials will be in accordance with Progress Energy's QA Program for Safety Related material. The sealant and its interface with the class 2 stainless steel piping has been evaluated and is acceptable for use in this application per plant procedures. | |||
: 5. Following installation of a clamp: | |||
: a. A system leakage test at normal operating pressure and normal operating temperature and a VT-2 examination in accordance with IWA-5000 will be performed on the portion of line number 6-SI-151 R-1 41 containing the clamp. | |||
: b. The area around the clamped valve will be monitored for leakage on a weekly basis in accordance with Article IX-6000 (c) with a record entered into AUTOLOG and with an entry made into the Corrective Action Program for appropriate evaluation and disposition in the event leakage is observed. | |||
: 6. An ASME Section Xl Code Repair/Replacement shall be performed during the next scheduled refueling outage, RO-28, which is currently scheduled to begin September 2013. If a condition leads to a forced outage of sufficient duration and scope to allow a code Repair/Replacement, the repair will be performed during this forced outage. | |||
Duration of Prooosed Alternative The requested relief will be used until an ASME Section XI Code Repair/Replacement activity is performed either during refueling outage RO-28 or during a forced outage of sufficient duration and scope to allow a Code Repair/Replacement activity. | |||
6 of 7 | |||
H. B. Robinson Steam Electric Plant, Unit No. 2 Fifth Ten-Year Interval Relief Request RR-07 Attachments: | |||
: 1. Structural Integrity Associates Examination Report SI-UT-837-1 for Component SI-837 Refueling Water Storage Tank (RWST) Drain Valve, September 27, 2012 | |||
==References:== | ==References:== | ||
: 1. Operability Concern Review 560007-10, "Operability Evaluation" 2. Progress Energy Nuclear Engineering Department Technical Report 12-188, "Robinson Nuclear Plant -Evaluation of a Leaking Drain Valve" September 14, 2012 3. Structural Integrity Associates Letter Report No. 1201045.401.RA, "Flaw Tolerance Evaluation of Leaking RWST-SI-837 Drain Valve Body", September 26, 2012 4. SI-UT-178 Revision 1"Site Specific Procedure for Phased Array Ultrasonic Examination of Valve SI-837" 5. Progress Energy, Carolinas Metallurgy Services Technical Report 12-188 for SI-837, September 14, 2012.7 of 7 | : 1. Operability Concern Review 560007-10, "Operability Evaluation" | ||
: 2. Progress Energy Nuclear Engineering Department Technical Report 12-188, "Robinson Nuclear Plant - Evaluation of a Leaking Drain Valve" September 14, 2012 | |||
: 3. Structural Integrity Associates Letter Report No. 1201045.401.RA, "Flaw Tolerance Evaluation of Leaking RWST-SI-837 Drain Valve Body", | |||
September 26, 2012 | |||
: 4. SI-UT-178 Revision 1"Site Specific Procedure for Phased Array Ultrasonic Examination of Valve SI-837" | |||
: 5. Progress Energy, Carolinas Metallurgy Services Technical Report 12-188 for SI-837, September 14, 2012. | |||
7 of 7 | |||
StruduralIntegrity Associates, Inc. | |||
NDE EXAMINATION | |||
==SUMMARY== | ==SUMMARY== | ||
EXAMINATION REPORT # SI-837-1 SI PROJECT# 1201070 Customer: | |||
Progress Energy Site: RNP U,,nit #2 Outage: N/A System: Safety Injection I Component: | EXAMINATION REPORT # SI-837-1 SI PROJECT# 1201070 Customer: Progress Energy Site: RNP U,,nit #2 Outage: N/A System: Safety Injection I Component: SI-837 Refueling Water Storage Tank (RWST) Drain Valve Examination Procedure: SI-UT-178 Revision I Code Edition and Addenda: ASME 2007 Edition with the 2008 Addenda Examination Record(s): 8AX 2.0 MHz SI-837-1 Calibration Data Sheet(s): 8AX 2.0 MHz S1837-!-Cal Summary: | ||
SI-837 Refueling Water Storage Tank (RWST) Drain Valve Examination Procedure: | The objective of this examination was to characterize the leak and surrounding area on the upstream side of valve SI-837 which is the RWST drain valve. | ||
SI-UT-178 Revision I Code Edition and Addenda: ASME 2007 Edition with the 2008 Addenda Examination Record(s): | The leak area was determined to be in the area of the transition between the upstream leg and the bonnet bore. Since the indication is in this transition area and the valve is full of borated water other volumetric examination methods were not considered to be good alternatives. This degraded valve is fabricated with cast austenitic stainless steel. There are no qualified ultrasonic examination techniques for examinations of cast austenitic stainless steel. However there are no requirements in ASME Section XI for qualified volumetric examination of valve bodies. The use of ASME Section V Article 4 does not apply to these examinations consequently ASME Section V Article 5 was used as a guideline where the rules were applicable. | ||
8AX 2.0 MHz SI-837-1 Calibration Data Sheet(s): | A "Best Effort" Ultrasonic examination was performed using Advanced Phased Array Techniques as have been qualified for other applications including weld overlay and dissimilar metal welds. | ||
8AX 2.0 MHz S1837-!-Cal Summary: The objective of this examination was to characterize the leak and surrounding area on the upstream side of valve SI-837 which is the RWST drain valve.The leak area was determined to be in the area of the transition between the upstream leg and the bonnet bore. Since the indication is in this transition area and the valve is full of borated water other volumetric examination methods were not considered to be good alternatives. | A Site Specific procedure (SI-UT-1 78) was written for these examinations. The purpose of the procedure is to find (detection) and determine the characteristics of the flaw(s) that are causing the known through-wall leakage in the cast stainless steel valve body of SI-837. Characterization will include length and through-wall sizing on a best effort basis, as well as determination if the flaws appear to be volumetric, planar, or casting related. | ||
This degraded valve is fabricated with cast austenitic stainless steel. There are no qualified ultrasonic examination techniques for examinations of cast austenitic stainless steel. However there are no requirements in ASME Section XI for qualified volumetric examination of valve bodies. The use of ASME Section V Article 4 does not apply to these examinations consequently ASME Section V Article 5 was used as a guideline where the rules were applicable. | A similar cast stainless steel valve body was examined to allow evaluation of techniques and familiarize the examiner with the expected responses from the material, geometry, and surface conditions of the valve under examination. | ||
A "Best Effort" Ultrasonic examination was performed using Advanced Phased Array Techniques as have been qualified for other applications including weld overlay and dissimilar metal welds.A Site Specific procedure (SI-UT-1 78) was written for these examinations. | |||
The purpose of the procedure is to find (detection) and determine the characteristics of the flaw(s) that are causing the known through-wall leakage in the cast stainless steel valve body of SI-837. Characterization will include length and through-wall sizing on a best effort basis, as well as determination if the flaws appear to be volumetric, planar, or casting related.A similar cast stainless steel valve body was examined to allow evaluation of techniques and familiarize the examiner with the expected responses from the material, geometry, and surface conditions of the valve under examination. | |||
Due to surface configuration the indication area could not be examined from 7" to 8". Two directional scanning was not possible or would not be affective in the flaw area due to configuration of the valve body. Circumferential scans were not performed due to flaw location being in an area which could not be examined and would not provide relevant information. | Due to surface configuration the indication area could not be examined from 7" to 8". Two directional scanning was not possible or would not be affective in the flaw area due to configuration of the valve body. Circumferential scans were not performed due to flaw location being in an area which could not be examined and would not provide relevant information. | ||
A dB transfer was preformed between the inside diameter (ID) reflection and the 0.5" deep side-drilled-hole used for calibration and 1.0 additional dB of gain was required to achieve an 80% FSH reflection from the ID surface. The 2.0 Mhz.search unit was used since it provided equivalent resolution and improved signal characteristics during the demonstration and provided a smaller footprint for improved contact on the valve surface.The indication is characterized as follows: It appears to be planar in nature with good signal to noise characteristics and aboul 3.5" in length. The Indication start point is 4.5" from Top Dead Center (TDC) of the SI-837 upstream leg of the valve body. The Leak is appears to be 100% through wall from 5.5" to 5.8" from TDC. The indication ends between 7" and 8" from TDC, due to the surface condition the end point cannot be determined ultrasonically since the transducer has a lift-offcondition between 7" and 8" from TDC.The areas between 0" and 4.5" as well as 8" and 10" were examined and do not contain flaw indications. | A dB transfer was preformed between the inside diameter (ID) reflection and the 0.5" deep side-drilled-hole used for calibration and 1.0 additional dB of gain was required to achieve an 80% FSH reflection from the ID surface. The 2.0 Mhz. | ||
Examiner: | search unit was used since it provided equivalent resolution and improved signal characteristics during the demonstration and provided a smaller footprint for improved contact on the valve surface. | ||
Ned Finney , Level: III Date: 09/27/2012 ft/ II 09/27/2012 SI Review: Chad McDonald Level: Ill Date: PGN Review: Pete Tingen Date: 09/27/2012 P rz S "g, ~U~i tb Page 1 of S VSw fetural Integrity Associates Report # SI-837-1 | The indication is characterized as follows: | ||
Progress Energy l Calibration File Name: SAX 20 MHz S1837-1-Cal Plant/Unit: | It appears to be planar in nature with good signal to noise characteristics and aboul 3.5" in length. The Indication start point is 4.5" from Top Dead Center (TDC) of the SI-837 upstream leg of the valve body. The Leak is appears to be 100% through wall from 5.5" to 5.8" from TDC. The indication ends between 7" and 8" from TDC, due to the surface condition the end point cannot be determined ultrasonically since the transducer has a lift-offcondition between 7" and 8" from TDC. | ||
RNP /2 Procedure No:ISI-UT-178 Revision 1 Componen/System: | The areas between 0" and 4.5" as well as 8" and 10" were examined and do not contain flaw indications. | ||
SI-837 Safety Injection Une # 6-SI-151R-141 Wedge Manufacturer: | Examiner: Ned Finney , Level: III Date: 09/27/2012 ft/ II 09/27/2012 SI Review: Chad McDonald Level: Ill Date: | ||
SI Refracted Angle Verification Model: 100102 Focal Law Angle Measured Index Material: | PGN Review: Pete Tingen Date: 09/27/2012 P rz S "g, ~U~i tb Page 1 of S | ||
Rexolite Angle Offset Velocity: | |||
2330 (m/s) 60W 60* 0.43" Wedge Angle: 16.20 450 450 0.48'Scan Direction: | VSw fetural Integrity Associates Page Report # SI-837-1 | ||
Axial 300 30- 0.55" Wedge Nominal OD: | _. of T ULTRASONIC PHASED ARRAY CALIBRATION RECORD Customer: Progress Energy l Calibration File Name: SAX 20 MHz S1837-1-Cal Plant/Unit: RNP /2 Procedure No:ISI-UT-178 Revision 1 Componen/System: SI-837 Safety Injection Une # 6-SI-151R-141 Wedge Manufacturer: SI Refracted Angle Verification Model: 100102 Focal Law Angle Measured Index Material: Rexolite Angle Offset Velocity: 2330 (m/s) 60W 60* 0.43" Wedge Angle: 16.20 450 450 0.48' Scan Direction: Axial 300 30- 0.55" 8. | ||
R/D Tech I Olympus Type: 34 conductor, 38 gauge coaxial Model: OmniScan MX Length: 8'Serial Number: OMNI-Z-1069 Connectors: | Wedge Nominal OD: | ||
I I-Pex Phased Array Module: OMNI-M-PA321128PR Intermediate Cable PA Module Serial No.: OMNI-Z-6036 Type: N/A Software Revision: | Instrument Search Unit Integral Cable Manufacturer: R/D Tech I Olympus Type: 34 conductor, 38 gauge coaxial Model: OmniScan MX Length: 8' Serial Number: OMNI-Z-1069 Connectors: I I-Pex Phased Array Module: OMNI-M-PA321128PR Intermediate Cable PA Module Serial No.: OMNI-Z-6036 Type: N/A Software Revision: 1.4R3 Length: N/A Instrument Settings: See Next Page Connectors: N/A Search Unit Manufacturer: GEIT Element Length: 1.15 mm Transmit Model: 115-000-613 Element Width: 2.70 mm Transmit Serial Number: 01VW13 Elements (Primary Axis): 16 Receive Model: 115-000-613 Elements (Secondar Axis): 2 Receive Serial Number: 01VW13 Inactive Element - Transmit: 0 Frequency (MHz): 2.0 Inactive Element - Receive: 0 Calibration Data Files Focal Law: 8A_0SK_2MTRL2X16_0-82_N_15mmHP.law Angles Generated: 0" through 820 (10 Increments) Wave Mode: Longitudinal Set-up File: 8AX 2.0 MHz S1837-1 .ops Focal Sound Path: 15rm Half Path Couplant I Batch Ultragel I1/11525F Calibration Block~s: SI-8-AX-02 Calibration Reflector Data Comments: | ||
1.4R3 Length: N/A Instrument Settings: | Calibration Reference %FSH Ref. Gain Wedge Reflector Angle Delay 0.5" Deep SDH 450 82% 33 dB 0.8 psec Active Element Checks performed at N/A N/A __ A N/A N/A Initial and Final Cal Checks Calibration Performed Examiner Level Date - Time Ned Finney III 09-26 18:55 Initial: _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ __ _ _ _ _ _ _ _ | ||
See Next Page Connectors: | Final: Ned Finney !4 II 09-26 19:40 Reviewed: Chad McDonald II 9-27-2012 PGN Review: Pete Tingen N/A 9/27/2012 | ||
N/A Search Unit Manufacturer: | |||
GEIT Element Length: 1.15 mm Transmit Model: 115-000-613 Element Width: 2.70 mm Transmit Serial Number: 01VW13 Elements (Primary Axis): 16 Receive Model: 115-000-613 Elements (Secondar Axis): 2 Receive Serial Number: 01VW13 Inactive Element -Transmit: | . Report # SI-837-1 Slnmwumi Iefgrity Associates ofg File Name 8A .0 MHz S1837-1.ops Me-uu.t.m Euseatial instrument Setting File File Format - | ||
0 Frequency (MHz): 2.0 Inactive Element -Receive: 0 Calibration Data Files Focal Law: 8A_0SK_2MTRL2X16_0-82_N_15mmHP.law Angles Generated: | Setup u UT Parameters into Report) .. . ..... | ||
0" through 820 (10 Increments) | Reading Result Selector Field A Pak Amplitudc In Gate A) | ||
Wave Mode: Longitudinal Set-up File: 8AX 2.0 MHz S1837-1 .ops Focal Sound Path: 15rm Half Path Couplant I Batch Ultragel I1/11525F Calibration Block~s: SI-8-AX-02 Calibration Reflector Data Comments: Calibration Reference | Field 2 __[A (Position Of Peak Signal In Gate A) | ||
% FSH Ref. Gain Wedge Reflector Angle Delay 0.5" Deep SDH 450 82% 33 dB 0.8 psec Active Element Checks performed at N/A N/A __ A N/A N/A Initial and Final Cal Checks Calibration Performed Examiner Level Date -Time Ned Finney III 09-26 | General Range .... | ||
Chad McDonald II 9-27-2012 PGN Review: Pete Tingen N/A 9/27/2012 | Start . ........ . 212" u I(eft) -. . | ||
.Report # SI-837-1 Slnmwumi Iefgrity Associates | Sound Velocity _.__ 229 20 inps LOCKED Pulser Pulser I PrFocal Law) LOCKED Tx/Rx Mode Pt Per Focal Law) LOCKED Voltage Lft~h PW Auto PRF mqptimum Receiver Receiver I (PerFocal Law) LOCKED Filter None Rectifier FW V;.ideo Filtter oft Averaging _ | ||
Reject0 Gailn-0 -fset 00B_ | |||
.... .... .. ........Rulers UT Unit True I) ph% Ruler Linear (%).T~G off-Gate On Cursor On Color Select ....Amplitudc Start (%)0.loperti Source INormal Probe/Prat Select Select Select TX RX Auto DetecttT ..PGM P'robe Configuration ScanipSetia Laws Connection P Auto Program Off Gate/Alarm Gate Gate Select ___ jate A: Synchro -__jPulse SStruaurul | Beam Delay Selection | ||
I Examination Scans Performed Yes No Component: | . .... Projectio~n . ... . . .. .. . ....... | ||
SI-837 Safety Injection Valve Drawing #: 5379-03429 (1) Axial (Facing Downstream) | Rulers UT Unit True I) ph | ||
[ El Component Configuration: | %Ruler Linear (%). | ||
Valve Body Examination Area: Area Adjacent to Leak (2) Axial (Facing Upstream) | T~G off-Gate On Cursor On Color Select .... Amplitudc Start (%)0. | ||
El 0 Coverage: | loperti Source INormal Probe/Prat Select Select Select TX RX Auto DetecttT . . | ||
TDC of Valve to 10" clockwise Limitations: | PGM P'robe Configuration ScanipSetia Laws Connection P Auto Program Off Gate/Alarm Gate Gate Select ___ jate A: | ||
See Comments Below (3) Circumferential (Clockwise (I)) 1 l []Component Zero Datum: Circumferential | Synchro - __jPulse | ||
= TDC, Axial = Upstream Elbow to Valve Weld (4) Circumferential (Counterclockwise (I)) El I Weld Width: N/A Weld Length: N/A Examination Surface: OD Surface Notes: Temperature: | |||
770 | SStruaurul IntegrityAssociates Report # SI-837-1 Page Y" of - | ||
PHASED ARRAY ULTRASONIC EXAMINA TION RECORD Examination Data Sheet No.: 8AX 2.0 MHz SI-837-1 Calibration Data Sheet No.: 8AX 2.0 MHz S1837-1 -Cal Date: 5/2/2012 Time: Start: 1130 Finish: 1230 Work Order Number: 2136305-01 Line#: 6-SI-151R-141 IP&ID #: 5379-01082 Sht. 2 Plant: RNP Unit: 2 Procedure No.: SI-UT-178 Revision: I Examination Scans Performed Yes No Component: SI-837 Safety Injection Valve Drawing #: 5379-03429 (1) Axial (Facing Downstream) [ El Component Configuration: Valve Body Examination Area: Area Adjacent to Leak (2) Axial (Facing Upstream) El 0 Coverage: TDC of Valve to 10" clockwise Limitations: See Comments Below (3) Circumferential (Clockwise (I)) 1 l [] | |||
Component Zero Datum: Circumferential = TDC, Axial = Upstream Elbow to Valve Weld (4) Circumferential (Counterclockwise (I)) El I Weld Width: N/A Weld Length: N/A Examination Surface: OD Surface Notes: | |||
Indication start point is 4.5" from Top Dead Center (TDC) of the SI-837 upstream side of the valve body.The Leak is marked at 5.5" and appears to be 100% through wall from 5.5" to 5.8" from TDC.The indication ends between 7" and 8" from TDC Due to the surface condition of the valve the end point cannot be determined ultrasonically since the transducer has a lift-off Condition between 7" and 8" from TDC.The areas between 0" and 4.5" as well as 8" and 10" were examined and do not contain flaw indications. | Temperature: 770 Examination An21es: 00 through 820(2) ") As viewed facing downstream (2) Examination angles are generated in 1 increments Thermometer: 1791138 Examination Sensitivity: 40.0 din i | ||
Limitations: | Cal Due: 7/26/13 Examination Wave Mode: Longitudinal Indication Evaluation Comments: | ||
Due to surface configuration the indication area could not be examined from 7" to 8". Two directional scanning was not possible or would not be affective in the flaw area due to configuration of the valve body.Circumferential scans were not performed due to flaw location being in an area which the scan could not examine.Examination Surface Condition Adjustments: | Indication appears to be planar in nature with good signal to noise characteristics. | ||
dB transfer was preformed between the inside diameter (ID) reflection and the 0.5" deep side-drilled-hole used for calibration and 1.0 additional dB of gain was required to achieve an 80% FSH reflection from the ID surface. The 2.0 Mhz. search unit was used since it provided equivalent resolution and improved signal characteristics during the demonstration and provided a smaller footprint for improved contact on the valve surface.Examiner: | Indication start point is 4.5" from Top Dead Center (TDC) of the SI-837 upstream side of the valve body. | ||
N/A N/A N/A Date: | The Leak is marked at 5.5" and appears to be 100% through wall from 5.5" to 5.8" from TDC. | ||
The indication ends between 7" and 8" from TDC Due to the surface condition of the valve the end point cannot be determined ultrasonically since the transducer has a lift-off Condition between 7" and 8" from TDC. | |||
!Structural | The areas between 0" and 4.5" as well as 8" and 10" were examined and do not contain flaw indications. | ||
Limitations: Due to surface configuration the indication area could not be examined from 7" to 8". Two directional scanning was not possible or would not be affective in the flaw area due to configuration of the valve body. | |||
Circumferential scans were not performed due to flaw location being in an area which the scan could not examine. | |||
Examination Surface Condition Adjustments: dB transfer was preformed between the inside diameter (ID) reflection and the 0.5" deep side-drilled-hole used for calibration and 1.0 additional dB of gain was required to achieve an 80% FSH reflection from the ID surface. The 2.0 Mhz. search unit was used since it provided equivalent resolution and improved signal characteristics during the demonstration and provided a smaller footprint for improved contact on the valve surface. | |||
Ned Finney Examiner: Level: III Date: 09/26/2012 PGN Review: Pete TIngen t ý - Date: 09/27/12 Examiner: N/A Level: N/A Date: N/A N/A Date: | |||
Reviewer: ~v4 Le4/,!L. | |||
el: II Date: 09/27/2012 N/A Date: | |||
Chad McDonald a'ý/r AT Level: " | |||
!Structural IntegrityAssociates Report # SI-837-1 Page 5 of S | |||
[Examination Data Sheet No.: 8AX 2.0 MHz SI-837-1 Start of Indication Mid-Point of Indication owl1 I | |||
/ | |||
A-, | |||
2S78 L-L- - 4 U e IV}} |
Latest revision as of 22:11, 11 November 2019
ML12292A386 | |
Person / Time | |
---|---|
Site: | Robinson ![]() |
Issue date: | 10/05/2012 |
From: | Wheeler S Progress Energy Carolinas |
To: | Document Control Desk, Office of Nuclear Reactor Regulation |
References | |
RNP-RA/12-0101 | |
Download: ML12292A386 (16) | |
Text
Progress Energy 10 Serial: RNP-RA/12-0101 OCT 0 5 2012 Attn: Document Control Desk United States Nuclear Regulatory Commission Washington, DC 20555-0001 H. B. ROBINSON STEAM ELECTRIC PLANT, UNIT NO. 2 DOCKET NO. 50-26 1/RENEWED LICENSE NO. DPR-23 RELIEF REQUEST (RR)-07 FROM IMMEDIATE ASME CODE REPAIR OF REFUELING WATER STORAGE TANK DRAIN VALVE (SI-837)
FOR FIFTH TEN-YEAR INSERVICE INSPECTION PROGRAM PLAN Ladies and Gentlemen:
Pursuant to 10 CFR 50.55a(a)(3)(ii), Carolina Power and Light (CP&L) Company, now doing business as Progress Energy, requests relief from the 2007 Edition, through the 2008 Addenda, of the ASME Section XI Code requirement as stipulated in Paragraph IWC-3122.2 on the basis that compliance with the specified requirements would result in a hardship or unusual difficulty without a compensating increase in the level of quality and safety. Accordingly, please find Relief Request (RR)-07 enclosed. This relief request is being submitted because a through-wall flaw was discovered in the body of a Refueling Water Storage Tank (RWST) 6-inch cast stainless steel drain valve located outside in the plant yard on September 7, 2012. A subsequent inspection of RWST drain line piping and fixtures did not identify any additional through-wall leakage in similar piping and valves.
This flaw was not found during performance of an ASME Section XI Code inservice inspection; therefore,Section XI requirements do not technically apply until Code Repair/Replacement activities are conducted to correct the flaw. However, using conservative decision making and for flaw evaluation review expediency, Progress Energy is pursuing NRC acceptance of our position through the formal relief request process.
Progress Energy plans to install a leak limiting clamping device within 45 days of receipt of the requested relief. This will help ensure that the through wall flaw does not degrade to a condition requiring more intrusive compensatory measures or plant shutdown prior to the next refueling outage scheduled for September 2013.
Progress Energy Carolinas, Inc.
Robinson Nuclear Plant 3581 West Entrance Road Hartsville, SC 29550
' . I..
United States Nuclear Regulatory Commission Serial: RNP-RA/12-0101 Page 2 of 3 This letter contains the following Regulatory Commitments:
- 1. The valve will be shielded from environmental elements with access for inspection until a Code Repair/Replacement.
- 2. Until installation of a clamp or until a Code Repair/Replacement is performed:
- a. Operations personnel will visually monitor the leak each shift with results entered into AUTOLOG. A crack length greater than 1 inch or a leakage increase greater than 16 drops/minute will require station management attention and entered into the Corrective Action Program for appropriate evaluation and further actions.
- b. NDE personnel will perform ultrasonic volumetric examination of the flaw location every 90 days. A crack length greater than 7 inches will require station management attention and entered into the Corrective Action Program for appropriate evaluation and further actions.
- 3. Following installation of a clamp:
- a. A system leakage test at normal operating pressure and normal operating temperature and a VT-2 examination in accordance with IWA-5000 will be performed on the portion of line number 6-SI-151 R- 141 containing the clamp.
- b. The area around the clamped valve will be monitored for leakage on a weekly basis in accordance with Article IX-6000 (c) with a record entered into AUTOLOG and with an entry made into the Corrective Action Program for appropriate evaluation and disposition in the event leakage is observed.
- 4. An ASME Section XI Code Repair/Replacement shall be performed during the next scheduled refueling outage, RO-28, which is currently scheduled to begin September 2013. If a condition leads to a forced outage of sufficient duration and scope to allow a Code Repair/Replacement, the repair will be performed during this forced outage.
Any other actions discussed in this letter should be considered intended or planned actions. They are included for informational purposes but are not considered Regulatory Commitments.
United States Nuclear Regulatory Commission Serial: RNP-RA/12-0101 Page 3 of 3 If you have any questions concerning this matter, please contact Mr. Richard Hightower, Supervisor - Licensing/Regulatory Programs at (843) 857-1329.
Sincerely, Sharon A. Wheeler Manager - Support Services - Nuclear SAW/sjg
Enclosure:
c: Mr. V. M. McCree, NRC, Region II Ms. A. T. Billoch-Colon, NRC Project Manager, NRR Ms. F. E. Saba, NRC Project Manager, NRR NRC Resident Inspector, HBRSEP Unit No. 2
United States Nuclear Regulatory Commission Enclosure to Serial: RNP-RA/12-0101 ENCLOSURE Fifth Ten-Year Interval Inservice inspection Program Plan Relief Request Number RR-07 Safety Injection Valve SI-837 RR-07 7 pages to RR-07 5 pages
1,. !
H. B. Robinson Steam Electric Plant, Unit No. 2 Fifth Ten-Year Interval Relief Request RR-07 Relief Request Number RR-07 Safety Injection Valve SI-837 Relief Requested In Accordance with 10 CFR 50.55a (a)(3)(ii)
-- Compliance with the Specified Requirements of this Section Would Result in a Hardship or Unusual Difficulty without a Compensating Increase in the Level of Quality and Safety --
ASME Code Comoonent(s) Affected The affected ASME Code component is identified as Safety Injection system valve SI-837 and is a Class 2, 150 pound, manually-operated, 6-inch cast stainless steel, wedge, gate valve manufactured by Crane Co. The valve body is made of SA351, CF8M cast stainless steel material.
The SI-837 valve is an isolation valve within the Refueling Water Storage Tank (RWST) drain line, line number 6-SI-151R-141. The valve is horizontally orientated approximately two feet from the connection of the line to the RWST tank and is subject to a pressure of approximately 15 psi (the static head of the RWST tank). The drain line connects to the RWST tank approximately one foot above the base of the tank on the upstream side of the valve and is capped approximately three feet downstream of valve. The maximum operating temperature of the valve and line number 6-SI-151 R-141 is bounded by the operating temperature of the RWST which is 100'F. The line is normally maintained in a static condition due to the single connection to the RWST and insulated with a sheet metal exterior containing silicon/aluminum oxide/carbonate insulation. The insulation has been removed at the valve extending beyond the valve weld ends.
SI-837 is located in an outdoor environment next to the RWST, and is exposed to seasonal temperatures and precipitation. SI-837 is a manual valve, model number L61174AM manufactured by Crane Valve Company. Model L61174AM is used in the Safety Injection system only within the RWST drain line application. To determine the extent of condition, a walk down was performed of the RWST, piping and valves located outdoors within the vicinity of the RWST.
The walk down was focused on identifying any other leaks as indicated by the buildup of boric acid crystals on the exterior to the insulation. No additional evidence of boric acid residue was noted.
1 of 7
H. B. Robinson Steam Electric Plant, Unit No. 2 Fifth Ten-Year Interval Relief Request RR-07 Valve SI-837 provides system boundary isolation for the RWST and is normally closed and locked. The welded cap on the end of line number 6-SI-1 51 R-141 provides a permanent secondary system boundary.
Containment boundary is maintained through various isolation valves of various systems that penetrate the containment structure. The Safety Injection (SI) system is one such system that has various components inside and outside the containment structure. The RWST tank is located outside the containment structure and is the source of borated water for the Emergency Core Cooling systems (ECCS) and Containment Spray (CS) systems during and post design basis events. The RWST tank is vented to the atmosphere. Containment boundary is provided with redundant isolation provisions to assure that no unrestricted release of radioactivity to the environment will occur. This action is provided by normally open valves SI-864A & SI-864B. The containment boundary is established by the closure of valves SI-864A & SI-864B. Valve SI-837 valve is not a containment isolation valve, and does not provide a containment boundary function.
A2olicable Code Edition and Addenda Robinson Nuclear Plant entered the Fifth, 10-year ISI Inspection Interval effective July 21, 2012. The ASME Section XI Code applicable to the Fifth 10-year interval is the 2007 Edition through the 2008 Addenda.
Aoolicable Code Reauirement ASME Section X1 Code, subsection IWC, "Requirements for Class 2 Components of Light-Water Cooled Power Plants", subparagraph IWC-3122.2, "Acceptance by Repair/Replacement Activity".
Reason for Reauest Active leakage from a small circumferential flaw on the upstream side of the valve body of valve SI-837 at the transition between the valve pipe run and the valve neck was identified following investigation of boric acid deposits on the exterior of the insulation of line number 6-SI-151R-141. The flaw visually appears to be approximately 1/2" in length. The leakage was quantified at about one (1) drop every five (5) minutes and is estimated to be about 0.25 gallons per week. No change in the leak rate has been observed since initial discovery and quantification of the leak rate. The current leak rate does not challenge the RWST inventory make-up capabilities.
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H. B. Robinson Steam Electric Plant, Unit No. 2 Fifth Ten-Year Interval Relief Request RR-07 A catastrophic failure of valve SI-837 would drain the contents of the RWST tank onto the ground on the north side of the auxiliary building with an initial leakage rate of about 60 gallons per second. The grade in the area of the RWST would flow the water toward a catch basin. There are limited restrictions to the flow to the catch basin such that there is sufficient open area around the RWST tank to allow flow away from the auxiliary building. The auxiliary building door closest to valve SI-837 is not water tight however if a catastrophic failure were to occur there is a weir just inside the door that would prevent any significant water intrusion into the building. Equipment in the area is elevated such that a localized flood would not have any impact.
A Code Repair/Replacement of the valve will require entry of the unit into either Mode 5 (cold shutdown) or Mode 6 (refueling) where the RWST is not required to be operable. The unit is currently operating in Mode 1. Installation of a clamp on the body of valve SI-837 would constitute a non-Code repair.
Performing a Code Repair/Replacement activity at this time to correct a flaw that has such a minor leak rate (approximately 1 drop every 5 minutes) would create a hardship based on the potential risks associated with unit cycling and emergent equipment issues incurred during shutdown and startup evolutions.
No compensating increase in the level of quality and safety would be gained by immediate repair of the flaw.
Engineering evaluations and judgment provide a basis to conclude that the SI-837 valve body is capable of performing its design function until the next refueling scheduled for September 2013. Installation of a leak limiting clamping device would provide additional assurance that no significant increase in leak rate through propagation of the existing flaw or catastrophic failure of the valve body could occur.
The bases for the conclusion that valve SI-837 is capable of performing its design function until the next refueling outage scheduled for September 2013 include the results of visual and ultrasonic examinations and fracture mechanics analyses. The activities conducted in performing these examinations and analyses and the results obtained are discussed further below.
A visual examination of the flaw and area surrounding the flaw did not indicate that any previous repairs to the casting had been made. Valve SI-837 is part of original plant construction and manufacturing records are not readily available.
A digital microscope was used to obtain magnified images of the flaw indication.
Based on these recorded images, the indication appears to be a relatively tight 3 of 7
H. B. Robinson Steam Electric Plant, Unit No. 2 Fifth Ten-Year Interval Relief Request RR-07 crack with some rust colored areas suggesting corrosion was involved. In the images, a water droplet is seen forming at one end of the surface crack indication indicating that the through wall flaw does not extend the entire length of surface indication.
Specimen samples of deposits were obtained from the heat tracing, piping, and valve. When analyzed, the samples taken from the valve consisted of boric acid (or a related compound) and an insulation-like material composed of silicon/aluminum oxide /carbonate with a trace amount of chlorine.
Based on the digital microscopic examination of the valve, it is believed that the most likely cause of failure is an OD initiated environmentally assisted cracking mechanism such as stress corrosion cracking. Based on the reported thickness of 0.4 inches at the indication location, it is also believed that there is a relatively high probability of a casting defect (e.g. shrinkage porosity) is present at this location.
A phased array ultrasonic examination was performed on the cast austenitic stainless steel valve body of valve SI-837 to characterize the leak and adjacent areas on the upstream side of the valve. See Structural Integrity report SI-UT-837-1 for additional information on specific details of the examination and the results.
Fracture mechanics analyses were performed using the procedures of IWC-3600 of Section XI of the ASME code for the Robinson Nuclear Plant to evaluate the flaw tolerance of the SI-837 Refueling Water Storage Tank (RWST) valve body containing postulated through-wall flaws.
The allowable through-wall circumferential flaw length was determined to be 12.9 inches (without the weight of the leak sealing device included). The corresponding allowable through-wall flaw length for the axial flaw type is 23.2 inches.
UT exams performed by Structural Integrity Associates have estimated the actual flaw length to be approximately 2.5 to 3.5 inches.
The calculated allowable planar through-wall flaws are larger than the dimensions of the reported flaw. Therefore, the RWST SI-837 drain valve should be considered operable but degraded until the end of the evaluation period (approximately 15 months).
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H. B. Robinson Steam Electric Plant, Unit No. 2 Fifth Ten-Year Interval Relief Request RR-07 Prooosed Alternative and Basis for Use Referencing ASME Section XI Code subparagraph IWC-3122.3, "Acceptance by Analytical Evaluation", Progress Energy proposes to temporarily accept the as-found relevant condition (i.e. through-wall flaw) which would allow continued service instead of performing immediate flaw correction by a Code Repair/Replacement activity described in ASME Section XI Code subparagraph IWC-3122.2, "Acceptance by Repair/Replacement Activity".
Referencing ASME Section Xl Code subparagraph IWA-4133, "Mechanical Clamping Devices Used as Piping Pressure Boundary", Progress Energy requests relief from Mandatory Appendix IXof ASME Xl, Article IX-1000 (General) paragraph (b) specification of allowable clamp locations. Specifically, relief is requested from the limitation of the installation of clamping devices only on the weld ends of valves to allow installation of a clamp on the valve body.
Following installation of a clamp that would encompass the entire valve body, volumetric monitoring would not be feasible. However, as the flaw is circumferential in nature volumetric monitoring is not required under Mandatory Appendix IXof ASME Xl, Article IX-6000 (a) and (b). The planned clamp installation would constitute a non-Code repair because Article IX-1000 (General) paragraph (b) allows clamp installation on the welded ends of valves but would otherwise comply with all requirements of ASME Section XI Mandatory Appendix IX.
This proposed alternative is based on Progress Energy performing the following actions.
- 1. Completion of a walk down on September 25, 2012 of all piping and valves located outdoors within the vicinity of the RWST with no additional evidence of boric acid crystals on the exterior of piping and valve insulation indicative of a potential leak.
- 2. The valve will be shielded from environmental elements with access for inspection until a Code Repair/Replacement.
- 3. Until installation of a clamp or until a Code Repair/Replacement is performed:
- a. Operations personnel will visually monitor the leak each shift with results entered into AUTOLOG. A crack length greater than 1 inch or a leakage increase greater than 16 drops/minute will require station management attention and entered into the 5 of 7
H. B. Robinson Steam Electric Plant, Unit No. 2 Fifth Ten-Year Interval Relief Request RR-07 Corrective Action Program for appropriate evaluation and further actions.
- b. NDE personnel will perform ultrasonic volumetric examination of the flaw location every 90 days. A crack length greater than 7 inches will require station management attention and entered into the Corrective Action Program for appropriate evaluation and further actions.
- 4. Installation of a mechanical clamp complying with the requirements of ASME Section Xl, Appendix IX.All materials will be in accordance with Progress Energy's QA Program for Safety Related material. The sealant and its interface with the class 2 stainless steel piping has been evaluated and is acceptable for use in this application per plant procedures.
- 5. Following installation of a clamp:
- a. A system leakage test at normal operating pressure and normal operating temperature and a VT-2 examination in accordance with IWA-5000 will be performed on the portion of line number 6-SI-151 R-1 41 containing the clamp.
- b. The area around the clamped valve will be monitored for leakage on a weekly basis in accordance with Article IX-6000 (c) with a record entered into AUTOLOG and with an entry made into the Corrective Action Program for appropriate evaluation and disposition in the event leakage is observed.
- 6. An ASME Section Xl Code Repair/Replacement shall be performed during the next scheduled refueling outage, RO-28, which is currently scheduled to begin September 2013. If a condition leads to a forced outage of sufficient duration and scope to allow a code Repair/Replacement, the repair will be performed during this forced outage.
Duration of Prooosed Alternative The requested relief will be used until an ASME Section XI Code Repair/Replacement activity is performed either during refueling outage RO-28 or during a forced outage of sufficient duration and scope to allow a Code Repair/Replacement activity.
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H. B. Robinson Steam Electric Plant, Unit No. 2 Fifth Ten-Year Interval Relief Request RR-07 Attachments:
- 1. Structural Integrity Associates Examination Report SI-UT-837-1 for Component SI-837 Refueling Water Storage Tank (RWST) Drain Valve, September 27, 2012
References:
- 1. Operability Concern Review 560007-10, "Operability Evaluation"
- 2. Progress Energy Nuclear Engineering Department Technical Report 12-188, "Robinson Nuclear Plant - Evaluation of a Leaking Drain Valve" September 14, 2012
- 3. Structural Integrity Associates Letter Report No. 1201045.401.RA, "Flaw Tolerance Evaluation of Leaking RWST-SI-837 Drain Valve Body",
September 26, 2012
- 4. SI-UT-178 Revision 1"Site Specific Procedure for Phased Array Ultrasonic Examination of Valve SI-837"
- 5. Progress Energy, Carolinas Metallurgy Services Technical Report 12-188 for SI-837, September 14, 2012.
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StruduralIntegrity Associates, Inc.
NDE EXAMINATION
SUMMARY
EXAMINATION REPORT # SI-837-1 SI PROJECT# 1201070 Customer: Progress Energy Site: RNP U,,nit #2 Outage: N/A System: Safety Injection I Component: SI-837 Refueling Water Storage Tank (RWST) Drain Valve Examination Procedure: SI-UT-178 Revision I Code Edition and Addenda: ASME 2007 Edition with the 2008 Addenda Examination Record(s): 8AX 2.0 MHz SI-837-1 Calibration Data Sheet(s): 8AX 2.0 MHz S1837-!-Cal Summary:
The objective of this examination was to characterize the leak and surrounding area on the upstream side of valve SI-837 which is the RWST drain valve.
The leak area was determined to be in the area of the transition between the upstream leg and the bonnet bore. Since the indication is in this transition area and the valve is full of borated water other volumetric examination methods were not considered to be good alternatives. This degraded valve is fabricated with cast austenitic stainless steel. There are no qualified ultrasonic examination techniques for examinations of cast austenitic stainless steel. However there are no requirements in ASME Section XI for qualified volumetric examination of valve bodies. The use of ASME Section V Article 4 does not apply to these examinations consequently ASME Section V Article 5 was used as a guideline where the rules were applicable.
A "Best Effort" Ultrasonic examination was performed using Advanced Phased Array Techniques as have been qualified for other applications including weld overlay and dissimilar metal welds.
A Site Specific procedure (SI-UT-1 78) was written for these examinations. The purpose of the procedure is to find (detection) and determine the characteristics of the flaw(s) that are causing the known through-wall leakage in the cast stainless steel valve body of SI-837. Characterization will include length and through-wall sizing on a best effort basis, as well as determination if the flaws appear to be volumetric, planar, or casting related.
A similar cast stainless steel valve body was examined to allow evaluation of techniques and familiarize the examiner with the expected responses from the material, geometry, and surface conditions of the valve under examination.
Due to surface configuration the indication area could not be examined from 7" to 8". Two directional scanning was not possible or would not be affective in the flaw area due to configuration of the valve body. Circumferential scans were not performed due to flaw location being in an area which could not be examined and would not provide relevant information.
A dB transfer was preformed between the inside diameter (ID) reflection and the 0.5" deep side-drilled-hole used for calibration and 1.0 additional dB of gain was required to achieve an 80% FSH reflection from the ID surface. The 2.0 Mhz.
search unit was used since it provided equivalent resolution and improved signal characteristics during the demonstration and provided a smaller footprint for improved contact on the valve surface.
The indication is characterized as follows:
It appears to be planar in nature with good signal to noise characteristics and aboul 3.5" in length. The Indication start point is 4.5" from Top Dead Center (TDC) of the SI-837 upstream leg of the valve body. The Leak is appears to be 100% through wall from 5.5" to 5.8" from TDC. The indication ends between 7" and 8" from TDC, due to the surface condition the end point cannot be determined ultrasonically since the transducer has a lift-offcondition between 7" and 8" from TDC.
The areas between 0" and 4.5" as well as 8" and 10" were examined and do not contain flaw indications.
Examiner: Ned Finney , Level: III Date: 09/27/2012 ft/ II 09/27/2012 SI Review: Chad McDonald Level: Ill Date:
PGN Review: Pete Tingen Date: 09/27/2012 P rz S "g, ~U~i tb Page 1 of S
VSw fetural Integrity Associates Page Report # SI-837-1
_. of T ULTRASONIC PHASED ARRAY CALIBRATION RECORD Customer: Progress Energy l Calibration File Name: SAX 20 MHz S1837-1-Cal Plant/Unit: RNP /2 Procedure No:ISI-UT-178 Revision 1 Componen/System: SI-837 Safety Injection Une # 6-SI-151R-141 Wedge Manufacturer: SI Refracted Angle Verification Model: 100102 Focal Law Angle Measured Index Material: Rexolite Angle Offset Velocity: 2330 (m/s) 60W 60* 0.43" Wedge Angle: 16.20 450 450 0.48' Scan Direction: Axial 300 30- 0.55" 8.
Wedge Nominal OD:
Instrument Search Unit Integral Cable Manufacturer: R/D Tech I Olympus Type: 34 conductor, 38 gauge coaxial Model: OmniScan MX Length: 8' Serial Number: OMNI-Z-1069 Connectors: I I-Pex Phased Array Module: OMNI-M-PA321128PR Intermediate Cable PA Module Serial No.: OMNI-Z-6036 Type: N/A Software Revision: 1.4R3 Length: N/A Instrument Settings: See Next Page Connectors: N/A Search Unit Manufacturer: GEIT Element Length: 1.15 mm Transmit Model: 115-000-613 Element Width: 2.70 mm Transmit Serial Number: 01VW13 Elements (Primary Axis): 16 Receive Model: 115-000-613 Elements (Secondar Axis): 2 Receive Serial Number: 01VW13 Inactive Element - Transmit: 0 Frequency (MHz): 2.0 Inactive Element - Receive: 0 Calibration Data Files Focal Law: 8A_0SK_2MTRL2X16_0-82_N_15mmHP.law Angles Generated: 0" through 820 (10 Increments) Wave Mode: Longitudinal Set-up File: 8AX 2.0 MHz S1837-1 .ops Focal Sound Path: 15rm Half Path Couplant I Batch Ultragel I1/11525F Calibration Block~s: SI-8-AX-02 Calibration Reflector Data Comments:
Calibration Reference %FSH Ref. Gain Wedge Reflector Angle Delay 0.5" Deep SDH 450 82% 33 dB 0.8 psec Active Element Checks performed at N/A N/A __ A N/A N/A Initial and Final Cal Checks Calibration Performed Examiner Level Date - Time Ned Finney III 09-26 18:55 Initial: _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ __ _ _ _ _ _ _ _
Final: Ned Finney !4 II 09-26 19:40 Reviewed: Chad McDonald II 9-27-2012 PGN Review: Pete Tingen N/A 9/27/2012
. Report # SI-837-1 Slnmwumi Iefgrity Associates ofg File Name 8A .0 MHz S1837-1.ops Me-uu.t.m Euseatial instrument Setting File File Format -
Setup u UT Parameters into Report) .. . .....
Reading Result Selector Field A Pak Amplitudc In Gate A)
Field 2 __[A (Position Of Peak Signal In Gate A)
General Range ....
Start . ........ . 212" u I(eft) -. .
Sound Velocity _.__ 229 20 inps LOCKED Pulser Pulser I PrFocal Law) LOCKED Tx/Rx Mode Pt Per Focal Law) LOCKED Voltage Lft~h PW Auto PRF mqptimum Receiver Receiver I (PerFocal Law) LOCKED Filter None Rectifier FW V;.ideo Filtter oft Averaging _
Reject0 Gailn-0 -fset 00B_
Beam Delay Selection
. .... Projectio~n . ... . . .. .. . .......
Rulers UT Unit True I) ph
%Ruler Linear (%).
T~G off-Gate On Cursor On Color Select .... Amplitudc Start (%)0.
loperti Source INormal Probe/Prat Select Select Select TX RX Auto DetecttT . .
PGM P'robe Configuration ScanipSetia Laws Connection P Auto Program Off Gate/Alarm Gate Gate Select ___ jate A:
Synchro - __jPulse
SStruaurul IntegrityAssociates Report # SI-837-1 Page Y" of -
PHASED ARRAY ULTRASONIC EXAMINA TION RECORD Examination Data Sheet No.: 8AX 2.0 MHz SI-837-1 Calibration Data Sheet No.: 8AX 2.0 MHz S1837-1 -Cal Date: 5/2/2012 Time: Start: 1130 Finish: 1230 Work Order Number: 2136305-01 Line#: 6-SI-151R-141 IP&ID #: 5379-01082 Sht. 2 Plant: RNP Unit: 2 Procedure No.: SI-UT-178 Revision: I Examination Scans Performed Yes No Component: SI-837 Safety Injection Valve Drawing #: 5379-03429 (1) Axial (Facing Downstream) [ El Component Configuration: Valve Body Examination Area: Area Adjacent to Leak (2) Axial (Facing Upstream) El 0 Coverage: TDC of Valve to 10" clockwise Limitations: See Comments Below (3) Circumferential (Clockwise (I)) 1 l []
Component Zero Datum: Circumferential = TDC, Axial = Upstream Elbow to Valve Weld (4) Circumferential (Counterclockwise (I)) El I Weld Width: N/A Weld Length: N/A Examination Surface: OD Surface Notes:
Temperature: 770 Examination An21es: 00 through 820(2) ") As viewed facing downstream (2) Examination angles are generated in 1 increments Thermometer: 1791138 Examination Sensitivity: 40.0 din i
Cal Due: 7/26/13 Examination Wave Mode: Longitudinal Indication Evaluation Comments:
Indication appears to be planar in nature with good signal to noise characteristics.
Indication start point is 4.5" from Top Dead Center (TDC) of the SI-837 upstream side of the valve body.
The Leak is marked at 5.5" and appears to be 100% through wall from 5.5" to 5.8" from TDC.
The indication ends between 7" and 8" from TDC Due to the surface condition of the valve the end point cannot be determined ultrasonically since the transducer has a lift-off Condition between 7" and 8" from TDC.
The areas between 0" and 4.5" as well as 8" and 10" were examined and do not contain flaw indications.
Limitations: Due to surface configuration the indication area could not be examined from 7" to 8". Two directional scanning was not possible or would not be affective in the flaw area due to configuration of the valve body.
Circumferential scans were not performed due to flaw location being in an area which the scan could not examine.
Examination Surface Condition Adjustments: dB transfer was preformed between the inside diameter (ID) reflection and the 0.5" deep side-drilled-hole used for calibration and 1.0 additional dB of gain was required to achieve an 80% FSH reflection from the ID surface. The 2.0 Mhz. search unit was used since it provided equivalent resolution and improved signal characteristics during the demonstration and provided a smaller footprint for improved contact on the valve surface.
Ned Finney Examiner: Level: III Date: 09/26/2012 PGN Review: Pete TIngen t ý - Date: 09/27/12 Examiner: N/A Level: N/A Date: N/A N/A Date:
Reviewer: ~v4 Le4/,!L.
el: II Date: 09/27/2012 N/A Date:
Chad McDonald a'ý/r AT Level: "
!Structural IntegrityAssociates Report # SI-837-1 Page 5 of S
[Examination Data Sheet No.: 8AX 2.0 MHz SI-837-1 Start of Indication Mid-Point of Indication owl1 I
/
A-,
2S78 L-L- - 4 U e IV