Update Feb 14
Meeting a 10am this morning.
Update Jan 30
I forgot to brag about my capabilities. I am solely responsible for pushing the NRC into making the set point drift a issue with the BWROG. I caught the drastic increase of setpoint drift LERs. Basically I said the SRVs over time with setpoint drift and leakage, unreliable parts...was a threat to the industry. It is interesting the NRC only choose the set point drift. The industry generally withholds all information about valve leakage and abnormal temperatures. So it is really hard to figure out how much leakage is going on in the industry by outsiders.
Check out my concerns at Hope Creek and Pilgrim in Adams? These valves are defective and they are sitting on a precipice of hell.
Update
Oh, this guy is in my cell phone calendar.
January 29, 2019 Title: Public Phone Call with the Boiling Water Reactor Owner's Group (BWROG) Regarding the Target Rock Safety Relief Valve (SRV) Setpoint Drift Issue February 14, 2019, 10:00 AM to 11:00 AMDate(s) and Time(s):
Location: Teleconference
Category: This is a Category 2 meeting. The public is invited to participate in this meeting by discussing regulatory issues with the Nuclear Regulatory Commission (NRC) at designated points identified on the agenda. Purpose: For the BWROG to provide a status update of activities being taken to address the Target Rock SRV Setpoint Drift Issue. Contact: Joe Golla 301-415-1002 joe.golla@nrc.gov
NRC NRC Staff Participants: External Boiling Water Reactors Owners Group
Teleconference:
Bridge Number Pass Code (888) 606-7810 16608
***The magnitude of the non performance issues here are astonishing. Most of the below information is new. Most has not been publicly documented. This reminds me of Pilgrim before their 2015 blizzard trip. The vast amount of non performance was secret. Then three failed. These valves are very delicate for their harsh safety environment. These safety valves may cycle up to 400 times in a accident.
Safety ValvesJanuary 28, 2019
SUBJECT: HOPE CREEK GENERATING STATION UNIT 1 – INTEGRATED INSPECTION REPORT 05000354/2018004) SRV Main Seat Leakage In NRC IR 2018002, the Semi-Annual Trend review section documented multiple high SRV tailpipe temperatures and conclusions that two of these SRVs, ‘H’ and ‘K’, were exhibiting signs of main seat leakage. Then, in NRC IR 2018003, an annual sample conducted for ‘H’ SRV and ‘D’ MSL issues documented that on September 5, 2018. On that date, PSEG also initiated NOTF 20803213 recommending that engineering review the conclusions and corrective actions from a 2014 causal evaluation (ACE 70168360) due to the inspector’s questions. Upon further review, the inspectors noted that PSEG had not taken action on NOTF 20803213 because even though there was automatic relief valve seat leakage it had not progressed and begun generating cyclic noises associated with condensate induced water hammer. In 2014, these noises associated with condensate induced water hammer occurred in the torus approximately ~20 times/min. October 1, 2018, the inspectors noted that PSEG initiated NOTF 20806044 for degrading conditions associated with the ‘H’ SRV main leakage, and then documented the reoccurrence of the condensate induced water hammer in the torus in NOTF 20814836 on December 20, 2018. As of December 31, 2018, PSEG initiated actions to develop an adverse condition monitoring (ACM) plan and operation technical decision making (OTDM) document for the issue. In addition, PSEG initiated NOTF 20816775 when the inspectors determined that the ‘H’ SRV main seat leak rate data from August to December 2018 was incorrect and did not include peer checks.
Got three of these guys. Basically these valves are similar to the SRV. It has no remote function. These guys got a last ditch function with maintaining pressure in the vessel. It would be a horrible accident if these guys failed.
PUBLIC MEETING WITH BOILING WATER REACTOR OWNERS’ GROUP on SRVSDecember 10, 2018Licensee Event Report No. 2018-003-00 Cooper Nuclear StationThe pressure relief system includes three American Society of Mechanical Engineers code safety valves · (SV) [EIIS:SB] which are located on the main steam lines [EIIS:SB] within the drywell [EIIS:NH], between the reactor vessel [EIIS:RPV] and the first main steam isolation valve [EIIS:ISV]. The SVs provide protection against over pressurization of the nuclear system and discharge directly into the interior space of the drywell.
Technical Specification (TS) Limiting Condition for Operation 3.4.3 requires the safety function of three SVs to be operable. The nominal set pressure and tolerances for these valves are established in CNS TS Surveillance Requirement (SR) 3.4.3.1.
Target Rock Safety Relief Valve Setpoint Drift Issue for Boiling Water Reactors September 12, 201Agenda
• Background • Safety Relief Valve (SRV) Design Function • Safety Significance • Technical Specification (TS) Compliance • Industry Actions Considered in Past • Next Steps • Boiling Water Reactor Owners’ Group (BWROG) FeedbackBackground
• Purpose: To discuss Target Rock 2-stage SRV setpoint drift issue for boiling water reactors (BWRs). • Licensees continue to experience a large number of surveillance test failures with 2-stage Target Rock SRVs. • Typically TSs allow only one SRV failure. • TS operability allowance for setpoint drift for most plants is ±3 percent. • As found setpoint drift for a number of BWRs ranges between +3 to +10 percent. – Most significant instance being a setpoint drift of +18.5 percent.Background (cont.)
• Originally, the issue was addressed by Generic Safety Issue (GSI) B-55, “Improved Reliability of Target Rock Safety Relief Valves.” • GSI B-55 concluded the following: – Safety significance is low. • There is margin to reactor coolant system stress limits. – Industry was already pursuing actions to correct the setpoint drift. • Staff was satisfied with industry actions to resolve issue. – Regulations already require licensees to correct the setpoint drift (no new regulatory requirements are needed). • TSs, 10 CFR Part 50 Appendix B, 10 CFR 50.55a, and 10 CFR 50.65. • Therefore, GSI B-55 was closed in December 1999.SRV Design Function
• The SRVs are part of the nuclear pressure relief system and, in part, prevent overpressurization of the nuclear process barrier. • A select number of SRVs are used by the automatic depressurization system (ADS) to rapidly decrease reactor pressure during specific small-break loss-of-coolant accidents during loss of high-pressure injection scenarios. • The setpoint drift issue does not affect the ADS function.Safety Significance The NRC staff reviewed the licensee event reports (LERs) considering the following design aspects for determining the safety significance for SRVs that do not open at their expected setpoints:
• ASME Code pressure/service limits on the primary system. • Hydrodynamic loads on SRV discharge piping. • Performance of high-pressure injection systems.Safety Significance (cont.)
Based on the review of LERs, the NRC staff determined the safety significance associated with Target Rock 2-stage setpoint drift to be low.TS Compliance
• In the Standard Technical Specifications for General Electric BWR plants, Limiting Condition for Operation (LCO) 3.4.3 states: “The safety function of [11] S/RVs shall be OPERABLE.” • SR 3.4.3.1 states: “Verify the safety function lift setpoints of the [required] S/RVs” are within a specified range. • Surveillance Requirement 3.0.1 states that “[f]ailure to meet a Surveillance, whether such failure is experienced during the performance of the Surveillance or between performances of the Surveillance, shall be failure to meet the LCO.”TS Compliance (cont.)
• Following the guidance of Inspection Manual Chapter (IMC)-0326, “Operability Determinations & Functionality Assessments for Conditions Adverse to Quality or Safety,” if there is not a reasonable expectation of operability, the SRVs should not be considered operable. • NRC staff considers the repeated failure of Target Rock SRVs a challenge to a reasonable expectation of operability. This could lead to determination of inoperability and noncompliance with TSs.Past Industry Actions Industry has identified corrosion-induced oxide bonding to be the cause of the current setpoint drift issue for 2-stage Target Rock SRVs. The licensees have tried the following options since the closure of GSI B-55, but with limited success: • Application of platinum coatings to SRV pilot valve discs. • Change the pilot valve disc material to Stellite 21 in an effort to prevent corrosion bonding. • Enhanced SRV insulation to reduce corrosion and improve reliability. • Return to modified Target Rock 3-stage SRV (subject to downward setpoint drift concerns).
10Owners group slidesCraig Shepherd (DTE) – Committee Chairman
BWROG/NRC Meeting September 12, 2018
Copyright 2018, BWR Owners’ Group, All Rights Reserved
BWROG Target Rock SRV Performance Improvement Committee
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History/Scope
Formed in 2016
Committee Scope: address the common causes of repetitive Target Rock 2-stage SRV as-found set-point test failures in the fleet. • Technical Exchange Meetings: share site set point drift performance, best practices, roadmap planning • 2-stage valve focus • Scope focused on setpoint drift
Membership: DTE/Fermi, Duke/Brunswick, Exelon/FitzPatrick, NPPD/Cooper, PSEG/Hope Creek, TVA/Browns Ferry
Copyright 2018, BWR Owners’ Group, All Rights Reserved
3
2017/18 Activities
• Industry-shared IBAD procedure (application of Platinum to disc surface) • Autoclave Screening Test - used to help develop sputtering application process of Platinum on test coupons and comparison to IBAD. Obtained positive results. • Plasma Enhanced Magnetron Sputter Coating of (Quantity 3) pilot discs with Platinum. Performed steam validation testing with positive results. In process of obtaining BWROG product for utilizing Sputtering for application of Platinum on SRV pilot discs. • Static Autoclave Material Screening - baseline conditions of corrosion bonding with control group and screening other materials. (Started Aug. 24, 2018)
Copyright 2018, BWR Owners’ Group, All Rights Reserved
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2019 Planned Activities
Test different thickness of (sputtered) Platinum coated on pilot discs in valve lift tests. • Sputtering opens process space for different thicknesses of Platinum Coating. • Potential for fleet usage – Know that current thickness of Platinum coating provided step-improvement in set point drift performance. – Does increase in thickness provide more protection from corrosion bonding?
Copyright 2018, BWR Owners’ Group, All Rights Reserved
Initial scoping effort to understand current Tech Spec Limits and alternative licensing approaches. • Not a funded project at this time. • Initial discussions among multiple BWROG committees.
LER Reduction
Copyright 2018, BWR
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