What a Direct Current Voltage Gradient Survey Entails

A direct current voltage gradient survey is what is done to evaluate a pipeline for defects in its coatings. A pipeline coating is designed to help prevent corrosion from reaching the actual pipeline and causing rust, holes, and leaks. Finding abnormalities in the coatings is essential to ensuring the integrity of the pipeline and fixing any issues that arise prior to them becoming irreversible or dangerous. Below is an exploration of what a direct current voltage gradient survey entails.

Detecting holidays

During a direct current voltage gradient survey, a crew of three highly trained cathodic engineers will typically cover between one and three miles of the pipeline in question per day, the actual amount depends on the field conditions. While the cathodic engineers are walking the pipeline, they inspect it for holidays. A holiday is a pot where the epoxy wears from the pipe. This means the spot has no protection from corrosion and is much more exposed to the damages this can cause. When a holiday is located, it is tagged with a high accuracy GPS meter. Then, a stake is put in the ground for easy spotting.

Explaining the process

The crew of professional cathodic engineers will walk you through the entire direct current voltage gradient survey while they are there. Once they’ve successfully completed the survey along the entirety of the pipeline, they will explain their entire process and help you to come up with a plan for implementing any resolutions that may be needed. Each team is led by a professional engineer with a Cathodic Protection Specialist CP4 certification. The team will discuss any holidays they’ve identified and explain the severity to you. Then they will help you to come up with a plan to resolve the issues in a manner that works for your company and helps to prevent future holidays.

Now that you know what a direct current voltage gradient survey entails, it’s time to get in touch with the professionals. At Dreiym Engineering, we employ highly trained CP4-certified cathodic protection and corrosion engineers who aim to provide the highest quality surveys. Contact us today to discuss your specific needs and we can provide you with a quote for our services. We specialize in gas pipeline cathodic protection along with other types of cathodic protection to keep your pipeline safe from the harmful effects of corrosion.