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Topics
NESCC 2013 Survey – review of results
Buried pipe coatings
Seals for doors and penetrations to prevent flooding
NESCC discussion of additional industry needs
NESCC Survey Review
NESCC provides value; Task Group Reports are
generally useful to stakeholders
Construction Standards/New Plant issues
Aging of Plant Components and NDE
Cables
Concrete
Better communication between stakeholders; identify
the needed standards and prioritize reviews
Coatings on Buried Pipes
* Steering Committee discussion identified the need for standards addressing buried pipe coatings.
* Research revealed a standard is under development:
* ASTM Committee D33, Coating and Lining Work for Power Generation Facilities, initiated the effort in 2012.
* ASTM Work Item # WK36382: Standard Guide for the Selection of Coating for Maintenance, Repair, and Rehabilitation of Buried Pipe External Coatings for Power Generating Facilities.
* Task group lead: Jon Cavallo, UESI NUCLEAR SERVICES
* Jon provided a status update to the Steering Committee in October.
ASTM Standard Guide
* Guide will enable the user to logically address a number of technical aspects of buried pipe coating selection, including:
* The function of buried pipe coatings in nuclear power plants.
* The plant systems which may include coated buried pipe.
* The generic types of field-applied buried pipe repair and refurbishment coatings.
* Coating materials addressed include:
* Liquid applied
* Tape wraps
* Shrink sleeves
* Melt sticks
* Paste wraps
* Non-structural fiber composite wraps
* Thermal spray
Standard Guide - Continued
* Technical factors which affect the selection of field-applied buried pipe repair and refurbishment coatings
* In situ (in-ditch) factors which affect the selection of field-applied buried pipe repair and replacement coatings, and,
* ASTM and other standards used to evaluate the performance of field-applied buried pipe repair and refurbishment coatings.
* Provides guidance for the selection of coating materials to be used to repair of external coatings on buried pipe in power generating facilities and includes piping under the following conditions:
* Low temperature (200 F) Low pressure (excludes TBD)
* Excludes piping under federal regulations (PHMSA)
Standard Guide - Continued
* Selection of coating systems should be based upon both laboratory and in situ field testing
Laboratory testing –> accelerated screening
In situ field testing -> ensuring coating will perform satisfactorily in actual field conditions
* In many cases, the same protective coating systems can be used for either repair or rehabilitation coating work
Standard Guide - Continued
* PrecautionsExisting coatings may contain hazardous materials such
as asbestos and leadRepair/rehabilitation coating systems may contain
hazardous and/or flammable materials
* Limitations
Existing coatings -> visual inspection onlyDo not used holiday detectors on existing coatingsSelection of repair/replacement coating systems may be
limited by local, state or federal laws
Standard Guide - Continued
Pre-assessment
Obtain and review available information concerning
existing coating system
Determine relative soil corrosivity
Observe condition of bedding and backfill materials
Replacement bedding and/or backfill materials may be
required
Standard Guide – Continued
Existing coating systemVisually inspect existing coating system for
HolidaysCrackingPeelingDelaminationWrinklingBlisteringSubstrate corrosion
Coatings specialist reviews results
Standard Guide – Continued
Select coating system based onSoil corrosivityCondition of existing coating systemSite environmental conditionsDegree of surface preparation achievable
Standard Guide – Continued
Post assessment
Currently there is no scientific method for predicting coating
system end-of-life
Coating performance is determined by
Observation of impressed-current cathodic protection
system performance
Periodic visual inspections of coating systems via bell
holes
Empirically, coating system end-of-life is determined when
Full recoating cost < cost of repairs
Standard Guide – Continued
NACE complimentary activities
* 2 new task groups in the area of buried pipe coatings for
nuclear power plants:
* TG 481 – nuclear power plant buried pipe coating
condition assessment
* TG 485 – identification of existing buried pipe coatings in
nuclear power plants
* First meetings of both: 9/24/2013
NESCC Participation
* Steering Committee feels that the NESCC can provide
valuable information for the ASTM standard.
* Proposing a ‘quick hit’ task group to develop a list of
industry needs to be provided to the ASTM task group.
* NESCC members are welcome to join the ASTM or NACE
task groups (no need to be member of the SDO).
* Requesting input from the NESCC.
Seals for doors & penetrations to prevent
flooding* Steering Committee discussion identified the need for standards addressing seals.
* A search for existing standards was performed, yielding no results.
* A request was sent by ANSI/Sally to SDOs asking for their input:
ACI ASTM
ANS CSA Group
American Society of Civil Engineers Institute of Nuclear Materials Management
American Society of Heating, Refrigeration and Air-Conditioning
Engineers
Nuclear Information and Records Management Association
ASME NEMA
American Water Works Association MSS
American Welding Society
Request for Information on Seal Standards
The Nuclear Energy Standards Coordination Collaborative (NESCC) is seeking input
from Standards Development Organizations related to an issue currently of concern
in the nuclear energy industry: Seal Standards for Doors and Penetrations to
Prevent Flooding Damage.
Following the events at the Fukushima Daiichi Nuclear Power Station in 2011, the
ability of nuclear power plants to withstand flooding has become a greater
concern. The majority of U.S. nuclear power plants have been in operation for
several decades, and in many cases, some seals have been in place since the
plants were built, and age-related degradation of seals could have occurred. It is
recognized that improved materials and assessment methods are now available,
and the NESCC is requesting information on standards for such materials and
methods. If your organization is developing or has published a standard related to
this topic, please contact me at your earliest convenience.
Response to Date
* The following SDOs have replied to date:
* ANS – no standards
* ASME – closest are two of the B16 standards that discuss gaskets for pipe joints; however, these standards do not include design requirements for the gaskets
* NIRMA – no standards
* If no standards exist and if the concern is industry-wide, the NESCC may decided to pursue development of a standard
* More information will be coming