ML18142A249

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Industry Comments on Ti 2515-195 for Summary of May 16, 2018, Meeting with Nuclear Energy Institute and Industry to Discuss Anchor Darling Fate Valve Draft Temporary Instruction
ML18142A249
Person / Time
Site: 99902028
Issue date: 05/16/2018
From:
Nuclear Energy Institute
To:
Office of Nuclear Reactor Regulation
Benney B
References
Download: ML18142A249 (35)


Text

Public Meeting to Discuss Draft Temporary Instruction 2515/195 NEI Discussion May 16, 2018

© 2018 Nuclear Energy Institute 1

Opening Remarks

  • Steve Geier - NEI
  • Scot Greenlee - Exelon

© 2018 Nuclear Energy Institute 2

Summary Comments

  • The inspection requirements in draft TI 2515/195 are not aligned with the industry methodology and guidance that utilities have committed to implement:

- Flowserve Part 21

- BWROG Guidance

- NEI Anchor Darling Double Disc Gate Valve (ADDDGV) Industry Resolution Plan

- Commitments made by utilities in their December 2017 submittals to the NRC

  • The main objective of the TI should be to verify that utilities executed their committed actions

© 2018 Nuclear Energy Institute 3

Summary Comments

  • As written, the TI reflects an excessively conservative approach that does not adequately consider:

- The positive results of ADDDGV internal inspections

- The results of existing thread friction testing

- A graded inspection approach using risk

- Existing design criteria for valves

  • The Industry has significant concerns with draft TI 2515/195 and asks that the NRC revise it to align with the BWROG guidance (TP16-1-112 rev. 4) and commitments made by utilities in their Dec 2017 submittals to the NRC

© 2018 Nuclear Energy Institute 4

TI Applicability

  • The inspection should be limited to active safety-related (SR) MOVs
  • The TI should specifically exclude passive safety-related MOVs or SR valves with manual gearboxes from the scope of the inspection

© 2018 Nuclear Energy Institute 5

TI Objectives

  • The inspection should focus on verifying execution of what was committed per industry guidance, regarding:

- Identification of affected valves

- Evaluation of valve susceptibility

- Implementation of corrective actions

  • The inspection should not be an independent verification that the SR valves are capable of performing their safety function

- Independent verification may implement a level of rigor not appropriate for verifying resolution of this industry issue

  • The inspection should focus on implementation of the industry corrective actions rather than just susceptibility

© 2018 Nuclear Energy Institute 6

TI Inspection Requirements

  • The evaluation section specifies certain design criteria that is above and beyond industry guidance and current regulation, such as:

- Use of motor actuator stall in evaluating the torque capability of the wedge pin rather than the torque requirements specified in the stations NRC approved GL 96-05 program

- Methodology for evaluating wedge thread shear capacity that may differ from existing approved vendor weak-link analyses

- Review of the press-fit collar design - not required if the wedge pin has adequate torque capacity to handle maximum applied torque

- Use of thread resistance only to determine valve operability for the short term

© 2018 Nuclear Energy Institute 7

Corrective Action

  • The industry implemented an effective corrective action plan based on industry guidance

- Diagnostic testing and stem rotation checks as described in BWROG Topical Report TP16-1-112, Rev 4 are effective methods in identifying stem-disc issues

- Torqueing the stem into the wedge to the maximum joint capacity may not be a feasible repair and does not account for other factors (e.g., Inconel pins)

© 2018 Nuclear Energy Institute 8

NRC Inspection Resources

  • Planned Inspection Hours in the TI seem inappropriately high

- Estimated time for the inspection is listed as 80 inspection hours

- Additional 24-32 hours for preparation and documentation

  • Changing the focus to verification of implementation of industry committed actions would result in more reasonable resource requirements

© 2018 Nuclear Energy Institute 9

Summary

  • The industry has aggressively pursued resolution of the ADDDGV issue
  • The industry has been very transparent on guidance and criteria being utilized to address the ADDDGV issue
  • The guidance and inspection criteria contained in the TI represents a disconnect with the industry on committed actions to resolve the issue
  • The Industry has significant concerns with draft TI 2515/195 and asks that the NRC revise it to align with the BWROG guidance and commitments made by utilities in their Dec 2017 submittals to the NRC

© 2018 Nuclear Energy Institute 10

QUESTIONS?

© 2018 Nuclear Energy Institute