United States Nuclear Regulatory Commission - Protecting People and the Environment

Forthcoming NRC Meeting with Industry to Discuss the Potential for Pressure Locking and Thermal Binding of Gate Valves




                                UNITED STATES
                        NUCLEAR REGULATORY COMMISSION
                    OFFICE OF NUCLEAR REACTOR REGULATION
                           WASHINGTON, D.C.  20555

                              January 13, 1994


NRC ADMINISTRATIVE LETTER 94-01:  FORTHCOMING NRC MEETING WITH INDUSTRY TO
                                  DISCUSS THE POTENTIAL FOR PRESSURE LOCKING
                                  AND THERMAL BINDING OF GATE VALVES


Addressees


All holders of operating licenses or construction permits for nuclear power
reactors.


Purpose


The U.S. Nuclear Regulatory Commission (NRC) is issuing this administrative
letter to inform addressees of the forthcoming NRC meeting with industry to
discuss the potential for pressure locking and thermal binding of gate valves.
This administrative letter does not transmit or imply any new requirements or
staff positions.  No specific action or written response is required.


Background


In March 1993, NRC published NUREG-1275, Volume 9, "Operating Experience
Feedback Report - Pressure Locking and Thermal Binding of Gate Valves."  In
the report, the staff reviewed operating events involving these failure
mechanisms and identified:  (1) the conditions under which the failure
mechanisms have occurred, (2) the spectrum of safety systems that have been
subjected to the failure mechanisms, and (3) the conditions that may introduce
the failure mechanisms under both normal and accident conditions.

Discussion

NRC has scheduled a public meeting to discuss Generic Letter (GL) 89-10,
"Safety-Related Motor-Operated Valve Testing and Surveillance."  This meeting
will focus on potential pressure locking and thermal binding of gate valves
installed in safety-related systems of both boiling-water and pressurized-
water reactors.  NRC will present an evaluation of related industry experience
and planned regulatory activities.  In addition, utility representatives may
discuss ongoing industry activities related to pressure locking and thermal
binding.  The NRC presentation will include responses to questions received
from interested parties, licensees, and applicants.  Attachment 1 is the
agenda for the meeting.

The meeting, which is open to the public, will be held on February 4, 1994,
from 8:00 a.m. to 5:00 p.m. at the New Orleans Marriott, 555 Canal Street, New
Orleans, Louisiana 70140, Telephone (504) 581-1000.


9401070119.

                                                           AL 94-01
                                                           January 13, 1993
                                                           Page 2 of 2


Related Generic Communications

In addition to GL 89-10, NRC has issued a number of generic communications
pertaining to either pressure locking or thermal binding of gate valves.
Among these are NRC Office of Inspection and Enforcement (IE) Circular 77-05,
"Fluid Entrapment in Valve Bonnets," IE Information Notice (IN) 81-31,
"Failure of Safety Injection Valves to Operate Against Differential Pressure,"
and NRC IN 92-26, "Pressure Locking of Motor-Operated Flexible Wedge Gate
Valves."

This administrative letter requires no specific action or written response.
If you have any questions about this letter, please contact the contact listed
below or the appropriate Office of Nuclear Reactor Regulation (NRR) project
manager.

                                  /S/'D BY BKGRIMES


                                  Brian K. Grimes, Director
                                  Division of Operating Reactor Support
                                  Office of Nuclear Reactor Regulation

Contact:  Allen G. Hansen, NRR
          (301) 504-1390

Attachments:
1.  Meeting Agenda
2.  List of Recently Issued NRC Administrative Letters

.                                                          Attachment 1
                                                          AL 94-01
                                                          January 13, 1994
                                                          Page 1 of 1


                                MEETING AGENDA


   PUBLIC WORKSHOP ON GATE VALVE PRESSURE LOCKING AND THERMAL BINDING


Welcome and Introduction                                       8:00 am
  J. Rosenthal, AEOD and J. Hannon, NRR

Pressure Locking and Thermal Binding Issues                    8:15 am
  E. Brown and C. Hsu, AEOD

Licensee Experience and Efforts
  D. Smith - Entergy, Grand Gulf                               9:30 am
     Identfying susceptible valves, tests to confirm thrust
     levels during pressure locking, corrective actions.

BREAK                                                   10:00-10:15 am

  M. Dowd - Commonwealth Edison, LaSalle                      10:15 am
     Identifying susceptible valves, steam system pressure
     locking, combined pressure locking/thermal binding

  R. Kadlec - American Electric Power, D. C. Cook             11:15 am
     Efforts to alleviate pressure locking at D. C. Cook

  W. Rowlett - Entergy, Arkansas Nucler One                   11:45 am
     Thermal binding, operation to prevent water in bonnet.

LUNCH                                                    12:15-1:15 pm

Valve Vendor Corrective Actions
  I. Ezeakoye - Westinghouse Electric Corp.                    1:15 pm
     Design modifications to alleviate pressure locking.

  D. Wright - Anchor Darling                                   1:45 pm
     Corrective actions to address pressure locking.

  J. Farrell - Velan                                           2:15 pm
     Thermal binding test and analysis.

NRC Draft Generic Communication                                2:45 pm
  T. Scarbrough, NRR

BREAK                                                     3:15-3:30 pm

Question and Answer Session                                    3:30 pm
  All presenters as panel

Closing Remarks                                                4:45 pm
  J. Rosenthal, AEOD and J. Hannon, NRR


Page Last Reviewed/Updated Thursday, March 29, 2012