What you Need to Know about Pipeline Corrosion?

Table of Content

• How to Detect Pipe Corrosion?
• Types of Materials Used in Pipes
• Types of Pipeline Corrosion
• How to Prevent Pipe Corrosion?
• What happens When Pipe Corrosion is Undetected?
• Key Takeaways

In the oil and gas industry, corrosion is one of the top causes of pipeline failure. Pipeline failure is understandably one of the public's leading fears when it comes to the oil industry, so proper detection and preventative measures are key to maintaining pipeline integrity. Let's look at how to detect and Prevent Pipeline Corrosion.

How to Detect Pipe Corrosion?

Corrosion can originate inside or outside of the pipes in a Pipeline. The causes of internal versus external corrosion vary widely. External corrosion starts with a failure of the coating; internal corrosion is a matter of chemistry, product in the line, and flow. No matter where the corrosion originates, however, it can spread to other areas; internal corrosion that spreads to affect external surfaces causes a leak, and vice versa.

To find its origin and detect other areas affected by corrosion, an NDT service, such as Nortech Advanced NDT, is part of the team to detect and mitigate the problem. We regularly test pipelines to detect issues that include pipe corrosion:

• Pipeline owners and operators place high-tech equipment (Smart Pigs) into the pipeline with the product, and as they move through the line they can detect thinning, deformation, and other potential problems.
• We then perform a visual inspection of suspected locations to detect obvious signs of damage, like pitting, cracks, or deformation.
• Test the surface of the exposed pipe to detect, measure, and repair any surface cracking.
• Use ultrasonic testing to detect thinning walls or signs of corrosion inside the pipeline.
• Employ advanced inspection methods to accurately measure anomalies and calculate pipe strength.

Types of Materials Used in Pipes

Pipes are required to be corrosion-resistant and should suit multiple applications. Issues such as pipeline internal corrosion, gas pipeline corrosion, and overall pipeline corrosion management should be addressed while considering pipe materials. Some common materials used include:

1. Steel:

Steel pipes are sturdy and suitable for oil and gas transportation. They are often protected against pipeline internal corrosion through coatings or corrosion-resistant alloys.

2. Copper:

Copper pipes are corrosion-resistant and often used in plumbing, heating, and cooling systems to prevent pipeline internal corrosion.

3. PVC (Polyvinyl Chloride):

PVC pipes are an excellent choice for water supply due to their resistance to pipeline internal corrosion and overall corrosion management.

4. PE (Polyethylene):

PE pipes are used for various applications, such as gas transportation and water distribution. They resist pipeline internal corrosion.

5. PP (Polypropylene):

PP pipes are resistant to chemicals and are often used in applications where preventing pipeline internal corrosion is crucial.

6. HDPE (High-Density Polyethylene):

HDPE pipes are resistant to pipeline internal corrosion and are used in water supply and drainage systems.

7. Cast Iron:

Cast iron pipes are strong and used for sewer systems and stormwater drainage, reducing the risk of pipeline internal corrosion.

8. Concrete:

Concrete pipes are sturdy and commonly used for sewage systems and culverts, with corrosion-resistant coatings to prevent pipeline internal corrosion.

9. FRP (Fiberglass Reinforced Plastic):

FRP pipes are corrosion-resistant and lightweight, making them suitable for chemical applications and helping manage pipeline corrosion.

10. Ductile Iron:

Ductile iron pipes are used for water and wastewater transmission, often with protective coatings to manage pipeline corrosion. Every material used in the manufacturing of pipes has its unique characteristics, that can be utilized to prevent pipeline internal corrosion and overall Pipeline Corrosion Management.

Appropriate pipeline corrosion inspection, detection, and prevention methods are essential in maintaining the integrity of the pipeline and extending its service life, particularly in the Oil and Gas Industry where pipeline corrosion is a significant concern. Pipeline corrosion technicians are vital in the monitoring and management of pipeline corrosion.

Types of Pipeline Corrosion

The different types of pipeline corrosion are as follows:

1. Uniform Corrosion:

This type of corrosion shows common, even material loss. It requires NDT methods, NDT techniques, and NDT equipment for monitoring.

2. Pitting Corrosion:

This form of corrosion appears as localized pits and is a significant concern in oil and gas pipeline corrosion management. NDT tests help detect it, and protective coatings can be applied to prevent it from occurring.

3. Crevice Corrosion:

This corrosion occurs in gaps. It can be prevented in the oil and gas industry by using design and maintenance practices, including NDT techniques. NDT equipment may be used for monitoring.

4. Galvanic Corrosion:

This corrosion is caused by the electrochemical interaction between metals. It requires isolating dissimilar metals, which may involve NDT Methods and the work of a pipeline corrosion technician.

5. MIC:

This type of corrosion is caused by microbial activity. This affects pipeline internal corrosion. It is necessary to create controlling conditions and apply biocides to prevent corrosion in the Oil and Gas Industry.

6. Erosion Corrosion:

Caused by mechanical wear, this form of corrosion is relevant to gas pipeline corrosion. Materials and coatings are chosen to resist it and are often aided by Non-destructive Testing.

7. Stress Corrosion Cracking (SCC):

This corrosion is caused by a combination of tensile stress and corrosion. This form of corrosion is a cause for concern in pipeline corrosion management. Material selection and stress management, sometimes assisted by NDT methods, are vital to avoid this kind of corrosion.

8. Hydrogen-induced cracking (HIC):

This corrosion is caused by Hydrogen absorption and can be prevented by choosing materials less susceptible to embrittlement. To avoid this, pipelines are sometimes monitored using non-destructive testing techniques and NDT Equipment.

How to Prevent Pipe Corrosion?

The best way to prevent pipe corrosion is to have a tightly adhered protective coating over 100% of the surface. Employing routine maintenance and treating all cases of corrosion prevents pipeline failure and corrosion-related accidents. It also helps ensure a pipeline remains secure and safe for the public. Maintenance, however, isn’t the only way to prevent Pipeline Corrosion and protect the public. Additional ways to prevent corrosion include:

• Using an electrical current as cathodic protection to prevent Galvanic Corrosion of the Pipeline
• Mixing the product with corrosion inhibitors, which are substances that can reduce contamination and corrosion
•  Using corrosive-resistant materials like plastic, some alloys, or stainless steel
• Applying an epoxy or specialized coating during the pipe manufacturing process

When data from the “Smart Pigs” show areas suspected of not being secure, they may be subject to Pipeline Integrity Management. If a line fails any part of this assessment, the owner will be required to perform repairs. These actions need to occur before the pipeline leaks!

What happens When Pipe Corrosion is Undetected?

Corrosion is commonly caused by a pipe’s exposure to oxygen, bacteria, and moisture. It’s a natural process that can occur in the open air or underground. Of course, undetected corrosion can be disastrous and lead to pipeline failure, which can lead to the leakage of potentially hazardous materials and noxious gases, which could pose a grave risk to public health and safety and even lead to fires or explosions.

Key Takeaways

• Safeguarding the safety and reliability of pipelines, particularly in industries like oil and gas, is of paramount importance.
• Non-destructive Testing techniques play a pivotal role in assessing pipeline conditions and detecting corrosion-related issues, ensuring the continued integrity of vital conduits

References:

1. National Energy Technology Laboratory

2. ResearchGate

3. Polyguard