Menu
Search
Filters
Close
Menu

Celebrate World Corrosion Awareness Day with 20% off eCourses and eBooks with code WCAD2024 at checkout!

FEM Simulation Analysis Of The Pipe-Casing Under Cathodic Protection

Picture for FEM Simulation Analysis Of The Pipe-Casing Under Cathodic Protection
Available for download

A crossing between buried pipelines and transportation arteries such as railways and highways is a common reality. Nowdays it is ordinary practice, and standards are available for such pratctise1, to protect such pipelines by encasing them in a wider pipe, named Casing. The goal is to protect the carrier pipe providing an outer shell capable of withstanding mechanical stresses and eventual corrosion, without leakage risk. In usual conditions this kind of safety measure should not be necessary, still due to the difficult maintenance and monitoring accessibility below railways and highways it becomes a dependable protection method and device.

Product Number: 51322-17713-SG
Author: Andrea Brenna, Luca Paterlini, Mehdi Attarchi, Marco Ormellese
Publication Date: 2022
Industries: Corrosion Monitoring and Control , Coatings and Linings , Coatings
$0.00
$20.00
$20.00

In the present study, pipe-casing under cathodic protection is modeled by using FEM. The inner and outer surface of the casing and coating defects at the pipe surface is considered as corrosion and protection interface that follows non-linear polarization behavior. The coating of casing, electrolyte resistivity in pipe-casing space and electrical resistivity between pipe-casing are the main variables. FEM model is approved by tens centimeters of the pipe-casing section experimental setup. After proofing the FEM model, it is scaled up to study more realistic dimensions and broader variable ranges.

The FEM simulations show that when the casing is bare and electrically isolated from the pipe, coating defects of the pipe are easily protected in a wide range of solution resistivity in pipe-casing space. If pipe-casing resistance is reduced to lower than 10 ohms, the cathodic protection nullified, and corrosion could happen on the pipe coating defects. The presence of a coating on the inner surface of the casing will only lead to localization of the corrosion on its defects. Lower solution resistivity leads to an overall flattening of the potential distribution to an average value.

In the present study, pipe-casing under cathodic protection is modeled by using FEM. The inner and outer surface of the casing and coating defects at the pipe surface is considered as corrosion and protection interface that follows non-linear polarization behavior. The coating of casing, electrolyte resistivity in pipe-casing space and electrical resistivity between pipe-casing are the main variables. FEM model is approved by tens centimeters of the pipe-casing section experimental setup. After proofing the FEM model, it is scaled up to study more realistic dimensions and broader variable ranges.

The FEM simulations show that when the casing is bare and electrically isolated from the pipe, coating defects of the pipe are easily protected in a wide range of solution resistivity in pipe-casing space. If pipe-casing resistance is reduced to lower than 10 ohms, the cathodic protection nullified, and corrosion could happen on the pipe coating defects. The presence of a coating on the inner surface of the casing will only lead to localization of the corrosion on its defects. Lower solution resistivity leads to an overall flattening of the potential distribution to an average value.

Product tags
Also Purchased
Picture for Case Studies in the Assessment of Filled Casings
Available for download

51313-02386-Case Studies in the Assessment of Filled Casings

Product Number: 51313-02386-SG
ISBN: 02386 2013 CP
Author: James Warner
Publication Date: 2013
$20.00
Picture for Analysis and Evaluation of Cathodic Protection within a Vapor Corrosion Inhibitor Gel Filled Casing
Available for download

51316-7801-Analysis and Evaluation of Cathodic Protection within a Vapor Corrosion Inhibitor Gel Filled Casing

Product Number: 51316-7801-SG
ISBN: 7801 2016 CP
Author: Len Krissa
Publication Date: 2016
$20.00
Picture for CATHODIC OVERPROTECTION AND INTERFERENCE CONDITION ON A GAS TRANSPORTATION PIPE ENCASED IN A CASING PIPE IN THE PRESENCE OF WATER IN THE ANNULUS
Available for download

51318-11118-Effect of protective casing on the cathodic protection condition of a buried pipeline at rail crossi

Product Number: 51318-11118-SG
Author: Andrea Brenna / Fabio Brugnetti / Beatrice Refraschini / Silvia Beretta / Marco Ormellese
Publication Date: 2018
$20.00

At rail crossings and parallelisms, pipes for liquid and gas transportation shall be encased in a coated steel casing pipe. Laboratory tests investigate the protection and interference condition of carrier pipe and the casing where water is in the annulus.
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