ML24137A239

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NRC Staff Presentation on Nuclear Industry Check Valve Regulatory Activities by Nicholas J. Hansing, Office of Nuclear Reactor Regulation, U.S. Nuclear Regulatory Commission, at Nuclear Industry Check Valve Users Group (Nic) Annual Meeting
ML24137A239
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Issue date: 05/16/2024
From: Nicholas Hansing
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Nuclear Industry Check Valve Regulatory Activities Nicholas J. Hansing Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission NIC Meeting June 2024

Disclaimer This presentation was prepared by staff of the U.S. Nuclear Regulatory Commission (NRC). It may present information that does not currently represent an agreed upon NRC staff position. NRC has neither approved nor disapproved the technical content.

NRC Regulatory Activities applicable to Check Valves

  • ASME OM-2 Code Effort
  • ASME QME-1-2023 and Reformatted QME-1
  • Operating Experience

Current 10 CFR 50.55a Regulatory Requirements

  • Earlier editions of ASME OM Code streamlined
  • Incorporates by reference 2020 Edition of ASME OM Code with conditions, such as:

- 50.55a(b)(3)(viii) - 2020 Edition of Subsection ISTE is acceptable to implement without conditions or an alternative request

- 50.55a(b)(3)(xi) - supplements ISTC-3700 to require licensees to verify that valve operation is accurately indicated by supplementing valve position indicating lights with other indications. Modified for valves not susceptible to stem-disk separation

  • 50.55a(f)(7) - NRC IST Plan submittal requirements, as removed from 2020 Edition

Current 10 CFR 50.55a Regulatory Requirements

  • RG 1.192, Revision 4, lists OM Code Cases that are acceptable with or without conditions

10 CFR 50.55a Code Edition Proposed Rule Proposed rule issued 8/8/23 (88 FR 53384) to incorporate by reference the 2021 Edition of ASME BPV Code and 2022 Edition of OM Code IST proposed changes:

Remove conditions (b)(3)(ii)(A), (B), and (C) for 2022 Edition because incorporated in that edition Remove condition (b)(3)(iii)(B) for check valve bidirectional testing for new reactors because required in recent code editions used by new reactors Remove condition (b)(3)(iii)(C) for flow-induced vibration monitoring for new reactors because required by other regulations New condition (b)(3)(vii) to clarify use of snubber code cases New condition (b)(3)(x) to clarify sample expansion of Class 1 pressure relief valve testing based on setpoint testing NRC staff reviewing public comments Final rule scheduled to be issued on 1/10/25

10 CFR 50.55a Code Case Rulemaking (Revision 40)

Proposed rule issued 3/6/23 (88 FR 13717)

Proposed rule incorporates by reference RG 1.192, Revision 5, accepting ASME OM Code Cases OMN-28 through OMN-30 without conditions, and OMN-31 with conditions Proposed rule also extends the IST Code of Record update requirement from 10 years to 20 or 24 years for licensees that have updated their IST programs to at least the 2020 Edition of the ASME OM Code as incorporated by reference in 10 CFR 50.55a NRC staff reviewing public comments.

Final rule scheduled to be issued 10/29/2024

NUREG-1482 Update

  • NRC staff is considering an update to NUREG-1482 to provide additional information on the proposed new Code of Record update requirements and other recent developments.

Proposed ASME OM-2 Code ASME has prepared a proposed IST Code for pumps, valves, and dynamic restraints (or components that perform similar functions) in new and advanced reactors.

The new IST Code is referred to as the OM-2 Code.

ASME has distributed the proposed OM-2 Code for review by ASME OM Code committee members.

ASME plans to issue the OM-2 Code in 2024.

NRC staff is considering a new Regulatory Guide (RG) for acceptance of the OM-2 Code with applicable conditions.

ASME QME-1-2023 and reformatted QME-1

  • QME-1 updated in 2023
  • ASME is preparing a reformatted QME-1 standard to be more applicable for new and advanced reactors that might not use water-cooled systems
  • NRC staff plans to revise RG 1.100 to accept QME-1-2023 and reformatted QME-1 with conditions when available

Pressure Isolation Valves at Startup

  • Plant Scenario
  • Mechanical Agitation?

ASME OM Code Requirements ISTC-3630 ISTC-3630(f)

ISTC-5221 ISTC-5224

What has NRC Authorized?

Elements of Authorized Process

  • Obtain as-found results
  • Declare PIV inoperable per TS and enter into corrective action program
  • Proceduralized guidance provided, controlled by technical evaluation (agitation device, process)
  • Seat Leakage per normal test procedure

- If met, operable

- If not, repair or replace during outage

  • Mechanically agitated PIVs are repaired or replaced during the next refueling outage

Proposed Code Case

  • NRC staff (and others) provided comments
  • NRC staff generally in agreement with principal, but requested additional details be included

Recent Operating Experience

  • System: Safety Injection
  • Component: Check Valve (also a containment isolation valve)
  • Event: Valve declared inoperable due to seat leakage.

Valve packing leak allowed boric acid to accumulate and increase friction, preventing valve from shutting.

  • Result: Valve was cleaned, disassembled, inspected and repaired.

Recent Operating Experience

  • Disc separation of Condensate Heater 4B Outlet Check Valve resulted in partial flow blockage which caused secondary plant transients during AFW pump testing
  • NRC staff reviewing request.

Conclusion

  • NRC staff remains engaged in topics of interest to the check valve user community

QUESTIONS?

Future Questions Nicholas.Hansing@nrc.gov

The NRC is Hiring!

Openings are available here:

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