Corrosion Testing and Research |
Corrosion-Influenced Failure Simulation |
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USAF C-21 aircraft noted to have suffered from pitting corrosion during depaint operations. SwRI engineers were called in to determine the root cause of the pitting and to identify remedial methods to prevent future occurrences. |
Corrosion-related failure analyses are conducted by Southwest Research Institute (SwRI) for a wide range of clients and industries, including:
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Aerospace
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Barge/shipping
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Pipeline
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Oil and gas drilling equipment
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Pressure vessels
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Valve systems
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Architecture
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Electrical components
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Sporting and utility equipment
The scope of the failure analyses conducted ranges from simple examinations of failed components to determine the root cause of failure to limited-scope experimental studies to validate possible failure modes and mechanisms to identifying and verifying the technical and financial viability of engineering solutions.
Aerospace
USAF C-21 aircraft noted to have suffered from pitting corrosion during depaint operations. SwRI engineers were called in to determine the root cause of the pitting and to identify remedial methods to prevent future occurrences.
Pitting corrosion of a U.S. Air Force C-21 aircraft was
noted after paint stripping operations. Concern was raised
that the pitting was a result of the paint stripping
operation that the aircraft was subjected to. Three main
theories were postulated to explain the corrosion observed,
and a root cause analysis was performed to establish the
conditions leading to pitting on the aircraft and to suggest
remediation methods. It was determined that a long stripper
dwell time coupled with high concentrations of chloride and
sulfate in the rinse water used were the most likely cause
of corrosion. Another possibility was that corrosive agents
prior to initiation of stripping operations contaminated the
aircraft surface.
Based on the work conducted, the following recommendations
were made to mitigate the future occurrence of corrosion
during depaint operations:
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Subject aircraft to a washdown procedure prior to stripping
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Minimize the stripper dwell time
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Use rinse waters low in dissolved corrosive salts
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Develop an alternative stripping procedure that effectively removes paint but does not remove the chromate conversion coating
For each suggestion, experimental
results and procedures were developed to demonstrate the
validity of the approach and the benefits of each.
Barge/Shipping
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SwRI engineers investigated the corrosion of the void space in double-hulled barges and determined that though microbially influenced corrosion may have taken place, the organisms were environmental in origin and could not metabolize the wax paint used. |
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SwRI engineers investigated the corrosion of the void space
in double-hulled barges and determined that though
microbially influenced corrosion may have taken place, the
organisms were environmental in origin and could not
metabolize the wax paint used.
SwRI recently conducted an analysis of double-hulled barges
that had been experiencing corrosion in the void spaced
between hulls. It was initially suggested that microbially
influenced corrosion (MIC) was occurring and that the
microbes were utilizing the wax coating used to protect the
void space from corrosion as a nutrient source. Using
standard microbiology and analytical chemistry methods, SwRI
determined that the organisms recovered were environmental
in origin and were found to not metabolize the wax paint
coating as a nutrient source.
For more information about corrosion-influenced failure simulation, or how you can contract with SwRI, please contact James F. Dante, at jdante@swri.org or (210) 522-5458.
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Contact Information |
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Corrosion-Influenced Failure Simulation (210) 522-5458 |
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Related Terminology |
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corrosion research pipeline corrosion coatings corrosion sensors corrosion life prediction stainless steel laser Raman spectroscopy corrosion monitoring cathodic protection microbiologically influenced corrosion |
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Related Information |
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Assuring the Integrity of Mechanical Systems |
| Materials Engineering Department | Mechanical Engineering Division | SwRI Home |
Southwest Research Institute® (SwRI®), headquartered in San Antonio, Texas, is a multidisciplinary, independent, nonprofit, applied engineering and physical sciences research and development organization with 11 technical divisions.
January 03, 2013
