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tray current interference presents significant challenges in managing the integrity of buried
metallic piping systems. Stray direct current (DC) interference can result in high corrosion rates
while alternating current (AC) interference can pose safety hazards and result in moderately high
corrosion rates. By developing specific testing methodology and mitigation strategies to assess the
impact of both DC and AC interference, pipeline engineers are able to mitigate these specific challenges.
While strategies differ for each mechanism, the objectives and the results are the same; targeted
mitigation that enhances personnel safety, prevents accelerated corrosion rates and reduces the risk of
pipeline failures.
Mears Integrity Solutions blends the specialised skills of corrosion engineers with electrical engineers
who are qualified to assess the operational impact of both DC and AC interference sources. Mears
engineers have quantified through independent research and testing that both DC and AC mechanisms
can result in accelerated rates of corrosion on buried or submerged metallic piping systems and require
definitive mitigation strategies to avoid pipeline failures.
DC interference
The US National Bureau of Standards first studied DC interference in the early 1900s as a result of
“streetcar electrification”. Despite this and countless other studies in the past 100 years, DC interference
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