Menu
Search
Filters
Close
Menu

Important: AMPP System Update February 27 - March 11 – Limited Access to AMPP Digital Services. Act Now to Avoid Disruptions! - Learn More

AC Corrosion At Other Frequencies Part A: Field Investigation And Mitigation

Picture for AC Corrosion At Other Frequencies Part A: Field Investigation And Mitigation
Available for download
Product Number: 51321-16807-SG
Author: Wolfgang Fieltsch, P. Eng.; Fation Shahinas, P. Eng.; Andreas Junker Olesen, Ph.D., Eng.; Lars Vendelbo Nielsen, Ph.D., Eng.
Publication Date: 2021
$0.00
$20.00
$20.00

A 2018 field investigation on an NPS 6, approximately 4 km long, liquid pipeline, identified a rectifier as
the likely source of the elevated DC and AC current densities, which resulted in AC corrosion anomalies
detected during in-line inspections (ILI). The findings of this case study, presented in the NACE Corrosion
2019 Paper No. 13188, indicated that the 120 Hz rectifier ripple may have contributed to the accelerated
AC corrosion at this location.
This follow-up paper is Part A of a two-part further investigation into corrosion rates on cathodically
protected structures due to AC frequencies other than the fundamental power frequencies of 50 Hz and
60 Hz. Part A involves additional field testing on the subject pipeline, and commissioning of the
recommended AC mitigation and monitoring systems. Part B of this investigation will be presented in a
separate paper (NACE Corrosion 2020 Paper No. 14916) and will discuss the results of laboratory testing
to determine corrosion rates of cathodically protected steel in simulated soil conditions at various AC
frequencies.

A 2018 field investigation on an NPS 6, approximately 4 km long, liquid pipeline, identified a rectifier as
the likely source of the elevated DC and AC current densities, which resulted in AC corrosion anomalies
detected during in-line inspections (ILI). The findings of this case study, presented in the NACE Corrosion
2019 Paper No. 13188, indicated that the 120 Hz rectifier ripple may have contributed to the accelerated
AC corrosion at this location.
This follow-up paper is Part A of a two-part further investigation into corrosion rates on cathodically
protected structures due to AC frequencies other than the fundamental power frequencies of 50 Hz and
60 Hz. Part A involves additional field testing on the subject pipeline, and commissioning of the
recommended AC mitigation and monitoring systems. Part B of this investigation will be presented in a
separate paper (NACE Corrosion 2020 Paper No. 14916) and will discuss the results of laboratory testing
to determine corrosion rates of cathodically protected steel in simulated soil conditions at various AC
frequencies.

Product tags
Also Purchased
Picture for 04206 AC Corrosion: Corrosion Rate and Mitigation
Available for download

04206 AC Corrosion: Corrosion Rate and Mitigation Requirements

Product Number: 51300-04206-SG
ISBN: 04206 2004 CP
Author: Mark Yunovich and Neil G. Thompson, CC Technologies
$20.00
Picture for 03698 Estimating AC Mitigation Requirements
Available for download

03698 Estimating AC Mitigation Requirements for Pipelines Installed in High Voltage AC Corridors: Fault Conditions

Product Number: 51300-03698-SG
ISBN: 03698 2003 CP
Author: R. D. Southey, Eng. W. Ruan, F. P. Dawalibi, S. Fortin
$20.00
Picture for Effects of Seasonal Variation on AC Interference and Mitigation Design
Available for download

51318-11231-Effects of Seasonal Variation on AC Interference and Mitigation Design

Product Number: 51318-11231-SG
Author: Wolfgang Fieltsch / Ernesto Gudino / Fation Shahinas / Travis Wymenga
Publication Date: 2018
$20.00

This paper involved a case study of a project involving AC interference on pipelines located in Canada where soil resistivities increase rapidly by up to several orders of magnitude once water in the soil freezes in the winter.

 
Categories
Industry
Recently viewed
Popular tags
View all

Association for Materials Protection and Performance

© AMPP All Rights Reserved.
Membership Terms of Content Use
Contact Customer Support