Information Notice 2010-08, Welding and Nondestructive Examination Issues
| ML091670177 | |
| Person / Time | |
|---|---|
| Issue date: | 04/09/2010 |
| From: | Dan Dorman, Mcginty T, Tracy G NRC/NMSS/FCSS, Division of Construction Inspection and Operational Programs, Division of Policy and Rulemaking |
| To: | |
| Herrera T, NRO/DCIP/CCIB, 301-415-7138 | |
| References | |
| IN-10-008 | |
| Download: ML091670177 (5) | |
ML091670177 UNITED STATES
NUCLEAR REGULATORY COMMISSION
OFFICE OF NUCLEAR REACTOR REGULATION
OFFICE OF NUCLEAR MATERIAL SAFETY AND SAFEGUARDS
OFFICE OF NEW REACTORS
WASHINGTON, DC 20555-0001
April 9, 2010
NRC INFORMATION NOTICE 2010-08:
WELDING AND NONDESTRUCTIVE
EXAMINATION ISSUES
ADDRESSEES
All holders of an operating license or construction permit for a nuclear power reactor issued
under Title 10 of the Code of Federal Regulations (10 CFR) Part 50, Domestic Licensing of
Production and Utilization Facilities, except those who have permanently ceased operations
and have certified that fuel has been permanently removed from the reactor vessel.
All holders of or applicants for an early site permit, standard design certification, standard
design approval, manufacturing license, or combined license issued under 10 CFR Part 52, Licenses, Certifications, and Approvals for Nuclear Power Plants.
All holders of or applicants for a license for a fuel cycle facility issued pursuant to
10 CFR Part 70, Domestic Licensing of Special Nuclear Material.
PURPOSE
The U.S. Nuclear Regulatory Commission (NRC) is issuing this information notice (IN) to alert
addressees of recent operating experience involving welding and nondestructive examination.
The NRC expects recipients to review the information for applicability to their planned activities
and to consider actions to avoid similar problems. However, the suggestions contained in this
IN are not NRC requirements; therefore, no specific action or written response is required.
DESCRIPTION OF CIRCUMSTANCES
Prairie Island Inservice Inspection
On October 1, 2008, at Prairie Island Nuclear Generating Plan (Prairie Island), NRC inspectors
reviewed the weld control records of the licensee contractor that performed machine gas
tungsten arc welding of the structural weld overlay on a pressurizer surge nozzle dissimilar
metal weld. The NRC inspectors noted that the documented weld speed on several weld
control records had not changed as would be expected and as required by procedure. To
control the weld heat input (an essential welding variable), it is necessary to control the weld
head travel speed. The operating instruction specified that welders would use the values for
piping/nozzle radius and the desired travel speed to determine the appropriate travel speed
setting for the welding machine. In this case, contrary to welding procedure specifications, the welders did not determine and enter a new speed into the welding machine as the piping/nozzle
radius increased as weld layers were added. Notwithstanding, a subsequent engineering
evaluation determined that based on the travel speeds recorded in the weld control record, the
resulting heat inputs were within the acceptable range.
While evaluating this weld speed issue, the welding contractor discovered that incorrect welding
parameters had been used to apply the first layer of the temper bead weld over a section of the
ferritic nozzle adjacent to a stainless steel butter interface. Specifically, the welders had failed
to change temper bead welding parameters when transitioning from the butter to the nozzle, a
requirement which was not delineated in the operating instruction. The resulting heat input on
the ferritic nozzle exceeded that allowed by the welding procedure specifications. As a result, the weld had to be removed (ground out) and rewelded. An extent of condition review showed
that other structural weld overlays performed were applied correctly.
Additional information is available in Prairie Island Nuclear Generating Plant, Units 1 and 2, NRC Integrated Inspection Report (IR) 05000282/2008005; 05000306/2008005, dated February
10, 2009, and can be found on the NRCs public website in the Agencywide Documents Access
and Management System (ADAMS) under Accession No. ML090420033.
Welding Issues at Louisiana Energy Services, National Enrichment Facility
In May 2009, the NRC inspectors identified welding issues involving the construction of the
Louisiana Energy Services, National Enrichment Facility (LES NEF). The following are three
examples of failure to implement American Society of Mechanical Engineers (ASME) B31.3
"Process Piping" requirements for welding and nondestructive examination.
(1)
Progressive radiography sampling was not proceduralzed to comply with the
requirements of ASME B31.3. The NRC inspectors reviewed weld records and identified
examples where a designated lot of random radiography samples was not expanded
when results revealed a weld defect for work performed by a welder/welding operator in
Category M Fluid Service. Corrective actions included performing additional radiography
of production welds.
(2)
Welders were not qualified in accordance with ASME Section IX for manual tack welding
of pipes, as required by ASME B31.3. Corrective actions included additional
radiography of field welds with fused tacks that were not previously selected for random
radiography and requalification of all welders to perform manual tack welding.
(3)
Weld reinforcement height exceeding the maximum allowed by ASME B31.3 for
circumferential butt welds on pipe. LES NEF corrective actions included re-inspecting all
welds to ensure compliance with the ASME B31.3 maximum height of weld
reinforcement and correction of any welds that exceeded the maximum criteria.
Additionally, NRC inspectors identified examples where LES NEF did not meet requirements
regarding commercial grade dedication of cascade component welds. Additional information
regarding the above examples is available in NRC IR 70-3103/2009-002, dated June 26, 2009, at ADAMS Accession No. ML091770643 and NRC IR 70-3103/2009-007, dated January 27,
2010, at ADAMS Accession No. ML100271177. Subcontractor Welding Issues at Flamanville-3 in France
On October 22, 2008, inspectors for the French regulatory authority, Autorité de Sûreté
Nucléaire, inspected the welding records of Societ delle Fucine (SdF), a subcontractor under
AREVA who in turn is the primary contractor for the construction of Flamanville-3. The
inspectors reviewed documentation and quality assurance measures applied to the weld test
samples to support the manufacturing of an intermediate collar ring for a pressurizer. The
inspectors found that the subcontractor used welding rods that were not qualified and did not
conform to the American Society for Testing and Materials (ASTM) E208, the International
Organization for Standardization (ISO) 9001, and subcontractors own procedures. The welding
rods were considered unqualified because they were not tested before performing drop-weight
testing.
The inspectors found that the subcontractor SdF was aware that unqualified weld rods were
used for the test samples and decided to not generate a nonconformance report, which is
contrary to ASTM E208, ISO 9001, and the subcontractors own procedures. The subcontractor
only generated a nonconformance report following unsuccessful tests of the samples taken from
the intermediate collar ring of the pressurizer.
The French regulators determined that without the necessary documentation to demonstrate
conformance with the French nuclear construction code, it did not have the assurance that the
subcontractor manufactured the pressurizer components in accordance with specified
requirements. Also noted was that the primary contractor AREVA had not prevented the
nonconformances by its subcontractor. The French regulators required AREVA to perform the
following three actions:
(1)
Propose a way to demonstrate that the three pressurizer intermediate collar rings
already manufactured conformed completely to the required specifications. This
approach will not rely on subcontractors quality assurance (QA) program.
(2)
Implement a more effective surveillance of AREVAs supplier, such that these QA issues
do not repeat themselves.
(3)
Describe measures that AREVA will implement before any additional orders are placed
with the subcontractor SdF for the manufacture of pressure-boundary components, destined for French nuclear power plants.
BACKGROUND
NUREG-1425, Welding and Nondestructive Examination Issues at Seabrook Nuclear Station:
An Independent Review Team Report, dated July 28, 1990, describes lessons learned
regarding licensee radiographic and welding programs. (Agencywide Documents Access and
Management Systems (ADAMS) Accession No. ML090300351).
DISCUSSION
This IN provides examples of welding issues that illustrate the importance of licensee oversight
of contractors or subcontractors, including direct observation of welding activities while in
progress when possible, to ensure welders adhere to welding procedure specifications and QA
requirements. Specifically, 10 CFR Part 50, Appendix B, Quality Assurance Criteria for Nuclear
Power Plants and Fuel Reprocessing Plants: (1) Criterion VII requires that measures be
established to adequately control contractor materials and services, (2) Criterion IX requires a
licensee to establish adequate measures to ensure the control of special processes, including
welding, heat treating, and nondestructive testing. and (3) Criterion XVI requires that measures
be established to assure that conditions adverse to quality be promptly identified and
corrected.
CONTACT
This IN requires no specific action or written response. Please direct any questions about this
matter to the technical contacts listed below.
/RA/
/RA/
Timothy J. McGinty, Director
Daniel H. Dorman, Director
Division of Policy and Rulemaking
Division of Fuel Cycle Safety and Safeguards
Office of Nuclear Reactor Regulation
Office of Nuclear Material Safety and Safeguards
/RA/
Glenn Tracy, Director
Division of Construction Inspection
and Operational Programs
Office of New Reactors
Technical Contacts: Omid Tabatabai
(301) 415-6616
(404) 562-0533
Omid.Tabatabai@nrc.gov
Alain.Artayet@nrc.gov
(301) 415-7138
Tomas.Herrera@nrc.gov
Note: NRC generic communications may be found on the NRC public Web site, http://www.nrc.gov, under Electronic Reading Room/Document Collections..
ME0879 OFFICE
CCIB:DCIP:NRO Tech Editor
CTSB:DCIP:NRO
BC:CTSB:DCIP:NRO BC:FFLD:NMSS
NAME
THerrera
KAzariah-Kribbs
OTabatabai
MKowal
BSmith
DATE
06/05/09
06/12/09 via e-mail 02/26/10 via e-mail 06/18/09
02/26/10 via e-mail
OFFICE
BC:OIP
BC:CIB3:DCI:RII
BC:CVIB:NRR
LA:PGCB:NRR
NAME
CAbrams
JMoorman
MMitchell
CHawes CMH
DATE
01/12/2010
02/26/10 via email 03/10/10 via e-mail 03/15/10
OFFICE
PM:PGCB:NRR
BC:PGCB:NRR
D:NMSS:DFCSS
D:DCIP:NRO
D:DPR:NRR
NAME
DBeaulieu
MMurphy
DDorman
GTracy
TMcGinty
OFFICE
03/10/10
03/15/10
04/07/10
03/25/10
04/09/10