What Determines How Corrosive Your Soil Is?

Written by Angela

Reach out to Dreiym Engineering for any Corrosion, Electrical or Forensic Questions.

May 17, 2023

4 Cathodic Protection Testing Methodologies

Corrosion on a pipeline is an electrochemical reaction between the metal of the pipes and an electrolytic material, usually soil. Cathodic protection is designed to prevent that reaction from occurring to maintain the integrity of the pipeline.

However, cathodic protection systems must be checked regularly using a variety of testing methodologies to ensure they are still protecting the pipelines. Learn more about common testing methods used by specialists to keep your pipeline clean and functional.

Rectifier Outputs

Impressed current cathodic protection (ICCP) systems use rectifiers to convert alternating current (AC) to direct current (DC) in order to prevent corrosion. When a cathodic protection specialist arrives to test your system, they will use a voltmeter to measure the output on those rectifiers. If the output needs adjusting to optimize cathodic protection, the specialist can perform adjustments with fine or coarse tap settings.

Close Interval Potential Survey (CIPS)

If there are parts of your pipeline that are not adequately protected, the CIPS mode of testing will locate those areas. The tester places reference electrodes at five-foot intervals along the pipeline; meanwhile, each rectifier’s output is synchronized to cycle between its on and off settings. The testing specialist measures pipe-to-soil corrosion potential at each interval using a high-impedance voltmeter.

Galvanic Anode Current Output

To get a reading on the status of the anode, cathodic protection testing experts use a voltmeter to measure the anode’s open circuit potential. As the anode is consumed over time, its open circuit potential will shift in a positive direction.

AC Interference Survey

Is your pipeline located close to a high-voltage AC power line? If so, you’ll need to have your pipeline’s CP system periodically tested to ensure that the alternating current isn’t contributing to corrosion or safety concerns. Testing experts use a high-impedance voltmeter in conjunction with a copper sulfate half-cell for reference; should their readings indicate AC interference, they can recommend proper mitigation equipment.

In order to keep your pipeline’s cathodic protection system in top working condition, have it fully tested at least once a year. If rectifiers are present along your pipeline, have them tested on a bi-monthly basis by cathodic protection experts who use proper testing methodologies. The knowledge you gain from these tests can help you optimize your CP system and keep your pipeline safe from corrosion.

Contact Us Now

We have a busy schedule; reach out soon if you have any questions or projects.  We will make every effort to answer your questions right away.

About Dreiym Engineering

Dreiym engineering is a full-service engineering company, providing design, consulting, procurement, and construction services. Founded in 2014, we have grown from humble origins to serve our customers in a growing number of engineering fields. Our goal is to find business partners looking for electrical engineering, corrosion engineering, or other engineering services. Our primary office is just north of Houston, Texas, with an additional location in Austin, Texas. Dreiym Engineering is a small company based out of Texas that looks for the best opportunities to partner with companies and customers. We specialize in forensic engineering, fire investigation, and corrosion engineering. Give us a call or email for any questions you may have.

We are also available for any questions you may have about civil or mechanical forensic engineering through our partner engineers that service much of the United States and abroad.

If you are looking for help with any service, simply contact us to get started.


You May Also Like…

Cathodic Protection Engineers

Cathodic Protection Engineers

Cathodic protection (CP) is a technique used to prevent corrosion on metal surfaces by making the metal anode and introducing a cathode, which attracts the electron...

Pipeline Electrical Isolation

Pipeline Electrical Isolation

Pipeline electrical isolation is a process used in oil and gas pipelines to isolate the electrical systems from the surrounding environment. This process is important...