Pipelines transport oil, gas, water, and other critical resources over long distances, and a single unnoticed defect–like a small leak or thinning pipe well–can lead to hazards or failures. Because of this, conducting a regular pipeline inspection is critical for keeping them lasting longer and maintaining safety.
This guide walks you through the key steps of pipeline inspection, from gathering initial data to performing surface and internal assessments. You’ll also learn about common pipeline issues as well as best practices to keep your pipeline system safe and efficient.
What is a pipeline inspection?
Pipeline inspections are routine assessments that pipeline engineers carry out to evaluate the condition of pipe systems and confirm that these are still safe, efficient, and compliant. Engineers often use inspection checklists to identify possible risks such as leaks, pressure surges, or corrosion. After all, by systematically monitoring the system, you can detect issues early and take corrective actions on problems sooner.
As a rule, there should be detailed reports about pipeline inspections. A pipeline inspection report documents any hazards by the system. These reports are essential for maintaining compliance with industry standards and improving worker and environmental safety.
Key steps for conducting pipeline inspections
Your pipeline inspection checklist should give you a comprehensive picture of your pipe system. The following tips will help organize your inspection process.
Step 1: Information collection
First, collect past and present data, including:
- Design records
- Operation and maintenance histories
- Corrosion control procedures
- Regulatory compliance records
- Pressure test reports
These will allow you to decide which type of inspection you’ll perform (e.g. close-in inspection or CIS). You’ll look at various factors, such as pipeline material, age, operating conditions, and environmental exposure. For example, a close interval survey (CIS) might be necessary to assess the effectiveness of cathodic protection systems, while other methods like short-range ultrasonic testing (UT), current-voltage gradient (CVG), or AC attenuation inspection can help you detect corrosion activity or structural weaknesses.
Step 2: Surface inspection
You can then conduct an above-ground inspection to find coating defects and other signs of corrosion. This is the first hands-on step to check the condition of the pipeline. Key tasks include:
- Looking for cracks, rusts, dents, or discoloration
- Identify peeling, blistering, or missing protective coatings
- Examine pipeline supports, anchors, and surrounding soil for signs of instability or erosion
- Listen for unusual sounds, like hissing or unusual vibrations
Coating defects are especially critical, because they expose the metal underneath to environmental factors like moisture, soil, and chemicals. This speeds up corrosion and increases the risks of leaks.
Step 3: Internal inspection
Use the data from above-ground inspections to evaluate segments for pipe surface assessments. For buried pipelines, you might do targeted excavations to inspect sections with suspected corrosion or damage. These are some of the tasks:
- Look for corrosion or cracks on internal pipe surfaces
- Assess the condition of the coating inside the pipe
- Measure pressure and flow consistency to see if there are no blockages or leaks
- Check for sediment or debris buildup
- Check weld seams and joints for any cracks or misalignment
If you find any major defects, you’ll have to decide if you need to take corrective action right away or continuous monitoring is enough.
Non-destructive testing (NDT)
Non-destructive testing (NDT) isn’t required in every inspection, but you use it for deeper analysis–such as when you notice possible issues during visual inspections or as part of routine monitoring for aging pipelines. It’s a powerful method because it allows you to detect internal flaws without damaging the pipeline. Unlike visual inspections, which only check the surface, NDT gives you precise measurements of wall thickness, corrosion levels, and structural integrity.
It uses advanced techniques like:
- Ultrasonic testing (UT)
- Magnetic flux leakage (MFL)
- Radiographic testing (X-ray)
- Eddy current testing
You’ll be able to assess the pipeline’s structural integrity while it’s in use–there’s no need for shutdowns or service interruptions.
Pressure testing
Pressure testing is another inspection method that’s mainly used at certain stages of the pipeline–such as after new installations, major repairs, or modifications. Unlike NDT, you’ll have to stop pipe operations because you’ll fill the pipeline with either water (hydrostatic testing) or gas (pneumatic testing), then raise the pressure higher than normal.
This gives a pass/fail result. If the pipeline can hold the pressure, it means the pipeline is structurally sound. But if the pressure drops, you have to look for and repair any leaks before testing again.
Step 4: Data reporting
Throughout the inspection process, you’ll record findings such as corrosion levels, coating integrity, pressure test results, and any structural weaknesses that you see. To make this easier, you can use Lumiform’s pipeline inspection checklist for more organized documentation. You’ll also be able to generate reports instantly with it and get data analysis trends.
This step also involves evaluating data from the examination and logging any risk factors that need regular checking. In the report, make sure to include:
- Inspection dates
- Methods used
- Test results
- Identified defects
- Recommended actions
You can even categorize defects by severity to prioritize maintenance efforts.
Step 5: Corrective actions and follow-up
Finally, you’ll implement corrective actions based on the findings.
If you detected minor defects, solutions like coating repairs, sediment removal, or pressure adjustments might be enough. But for serious structural issues, you might need to conduct pipeline repairs, reinforcements, or even section replacements.
Depending on how severe the issue is, you might need to do immediate re-evaluations or schedule future monitoring to track the pipeline’s condition over time.
Common issues in pipeline inspections
During the inspection, these are the most common issues that you might find, and it’s important to fix them promptly:
- Corrosion and metal degradation: You’ll find this more in aging pipelines or those with compromised protective coatings.
- Coating failures: Protective coatings can degrade over time, leaving the underlying metal vulnerable to corrosion.
- Leaks and structural weaknesses: It’s easy not to notice small leaks, but if you don’t fix them early, they can lead to significant failures.
- Blockages and sediment buildup: These reduce flow efficiency and increase the pressure within the pipeline.
- Weld defects and joint failures: Causes include poor welding techniques, aging infrastructure, or stress from fluctuating temperatures and pressures.
- Third-party damage: This means accidental damage from excavation, construction, or heavy machinery nearby.
- Pressure irregularities: Sudden changes in pressure might mean there are leaks, blockages, or component failures.
Advantages of using a pipeline inspection checklist
People and businesses often overlook regular pipeline inspections. However, using a pipeline inspection checklist to regularly evaluate pipe systems helps:
You’ll be able to eliminate deficiencies while it is still possible and easy to do. Addressing small details is easier than repairing the entire system. And pipelines, in particular, need maintenance since they are at risk of corrosion.
You’ll prevent employee lawsuits. If a worker eventually gets sick or injured because a pipeline malfunctioned, your company may be taken to court. Keeping your employees safe by regularly assessing the state of your pipe systems is better for everyone.
It guarantees that all pipe operators are working efficiently to monitor pipe conditions.
It also leads to cost savings, since regular maintenance is always cheaper than installing a new system
Smooth pipeline inspections with workflow automation software
Getting the most out of your pipeline inspection checklist is easiest when you have workflow automation software like Lumiform. Lumiform’s mobile app and desktop software make it easy to perform quality and safety audits, report problems in a snap, and quickly assign corrective actions to responsible colleagues. The software streamlines team communication so that roles and responsibilities are clear, and you don’t miss an inspection.
When you use conduct pipe inspections with Lumiform:
- The AI checklist builder allows you to create digital pipeline inspection checklists and digitize any existing checklists
- There are over 12,000 ready-made templates to help companies start inspecting immediately
- The mobile app lets you and your employees assess pipelines online and offline, and guides you through every step of the inspection
- All your data is stored and converted into regular reports which help your business find patterns and common trends
- The ease of assigning and tracking tasks means that you can always stay on top of the work you’re doing
Try Lumiform for free today and streamline your pipeline inspections!