20
NuclearPlantJournal.com Nuclear Plant Journal, March-April 2015
Reactor
Vessel and
Internals
Aging
Management
Technologies
By Cynthia Pezze, Westinghouse Electric
Company LLC.
Cynthia Pezze
Cindy Pezze is Vice President of Global
Technology Development and Chief
Technology Officer for Westinghouse
Electric Company LLC, responsible
for overseeing the
development of new
technologies and
providing leadership
for company-level
programs related
to innovation
and engineering
excellence. Prior to
this appointment,
Pezze was Director
of Engineering
Excellence, driving
consistency in
the standards
and requirements
necessary for
delivering high-
quality engineered
products. Previous
positions include Chief Engineer for
Westinghouse’s New Plants Engineering,
and other business and operational
leadership stations for a variety of
technical areas.
Pezze has bachelor’s degrees in
mathematics and metallurgical
engineering from Allegheny College and
the University of Pittsburgh, respectively,
and has completed executive
management programs at Duquesne
University’s Beard Institute and the
University of Virginia’s Darden School
of Business.
When the U.S. Nuclear Regulatory
Commission (NRC) considered plant
operation beyond the original licensing
period of 40 years, they defined
requirements that plants must meet for
license renewal, including developing
and implementing a program to meet
them. The program, called an NRCAging
Management Program, is a tool to support
the effective management of age-related
degradation issues of critical components.
The Electric Power Research Institute
(EPRI) Materials Reliability Program’s
(MRP) inspection and evaluation
guideline (MRP-227-A) was developed
as a cooperative industry effort to provide
inspection and evaluation guidelines for
reactor internals for pressurized water
reactors (PWRs).
In response to the industry’s need to
evaluate, and if need be, address technical
challenges for the complex reactor vessel
internals,
Westing-
house performed a
very broad-spectrum
review of reactor
vessel internals de-
sign and materials.
The goal and re-
sult was to develop
a
comprehensive
understanding
of
mechanisms
that
could contribute to
the aging of these
complex
compo-
nents, enable predic-
tion of component
aging, and define
preventative tech-
niques to use to miti-
gate aging and pro-
vide economic maintenance throughout
the operation of the plant.
A key result of these efforts
is the Westinghouse PWR Reactor
Internals Aging Management Pre-
inspection Engineering Package (PIEP).
Westinghouse PIEP is preceded by
identifying the full scope of the reactor
internals aging management needs and
a program plan that addresses them.
With this knowledge, Westinghouse
develops the plant-specific PIEP, which
serves as an inspection roadmap. The
PIEP tools comply with MRP-227-A,
effectively implementing the guideline’s
requirements, and are also aligned with
MRP-228 inspection and generic aging
lessons learned aging management
requirements. The PIEP engineering tools
support defining a plant’s component
inspection details (CIDs), acceptance
criteria and inspection response plan
(IRP).
The outcome of developing CIDs
includes inspection illustrations with
sufficient detailed information to
support required industry MRP-227-A
inspections, including data gathering and
retention compliance. The acceptance
criteria provide a detailed inspection
basis for performing flaw tolerance
evaluations, with timely examination of
outage inspection results to support plant
reliability and return-to-service steps
within regularly scheduled maintenance
intervals. The IRPs are based on plant-
specific factors using an interactive tool
that employs expertise from all plant
operation perspectives and outlines
responses to the inspection. It is designed
to allow the plant to safely and quickly
return to power with activities that
support permanent mitigation, repair or
replacement strategies that are aligned
with a regularly scheduled maintenance
outage.
The Westinghouse PIEP program
has been implemented at plants and has
proven to be successful in positioning
them to meet industry and regulatory
requirements for supporting long-term
aging management of reactor internals.
Westinghouse has worked closely
with EPRI and the Pressurized Water
Reactor Owners Group, others in the
nuclear industry, and the U.S. NRC
in developing reactor vessel internals
aging management criteria. The PIEP
encompasses wide-ranging and in-depth
expertise and is a living strategy that
is continually reviewed and improved
based on technical advances, financial
management scenarios and integrated
planning solutions.
A few examples of the many
evaluation, mitigation and repair
techniques Westinghouse has developed
for the reactor vessel and internals
are highlighted. These are just a few
samples of the numerous methodologies
and technologies Westinghouse has
committed to developing and delivering
