Inspecciones de Infraestructuras
Infrastructure inspection is the first step to ensure the integrity and operational safety of critical facilities: buried pipelines, tank farms, gas distribution networks, and industrial plants. In environments where failure is not an option, having accurate data on the real condition of each asset makes the difference between operational continuity and an unplanned shutdown.
At Procainsa, we have been carrying out inspections of protected infrastructures for over 35 years for clients in Europe, North Africa, and South America. Our NACE (National Association of Corrosion Engineers) certified technical team combines cutting-edge technologies with a deep knowledge of international standards to offer reliable, documented, and actionable evaluations.
PROCAINSA
Which sectors do we perform infrastructure inspections for?
Our experience covers the most demanding industrial sectors in terms of integrity:
- Gas transport and distribution: high-pressure gas pipelines, urban distribution networks, LNG facilities.
- Refining and petrochemicals: process pipelines, crude oil and refined product lines, refinery distribution systems.
- Offshore and coastal infrastructure: subsea pipelines, port structures, platforms.
- Storage: tank farms, buried tanks, storage terminals.
- Gas stations and service stations: inspection of buried pipelines and double-wall systems.
- Chemical and pharmaceutical industry: process networks with critical integrity requirements.
Infrastructure inspection techniques we apply
We have a wide range of inspection techniques, selected and combined based on the characteristics of each facility and the evaluation objectives:
Coating Inspection with DCVG Technique
The DCVG (Direct Current Voltage Gradient) coating inspection technique is recognised for its accuracy in locating coating faults, as well as allowing effective auditing of the installed Cathodic Protection system.
This technique uses a direct current pulse generated by a current switch. Current flow through the soil causes a gradient of potential around defects in the coating. These are detected using two grounding electrodes that allow measurement using a specifically designed voltmeter. This system evaluates the electrical magnitude of the defects found.
Procainsa SA technicians will carry out the measurements and geo-locate the defects using a GPS system. The defects will be classified according to the highest percentage of IR (Rectification Index), thus identifying the most severe, moderate, slight or non-significant defects.
At Procainsa, we are committed to performing detailed inspections using the DCVG technique to ensure the integrity of coatings and the effectiveness of Cathodic Protection systems, thus providing a reliable solution to our customers’ needs.
Close Interval Potential Survey (CIPS)
CIPS is the standard technique for evaluating the effectiveness of the cathodic protection system along the entire length of a pipeline. On/off potentials are recorded at regular intervals—typically every meter—allowing the identification of sections with insufficient protection, areas affected by stray currents, and points with visually undetected coating failures.
We apply CIPS autonomously or in combination with DCVG to obtain a complete electrical characterization of each defect: severity, behavior, and effectiveness of protection in its immediate environment.
DCVG + CIPS — Combined inspection for maximum precision
The combination of both techniques is the most complete solution for the evaluation of buried pipelines. DCVG locates and quantifies coating defects; CIPS, applied in affected sections with measurements every meter (10 m upstream and 10 m downstream from the defect’s epicenter), determines the effectiveness of cathodic protection in that specific area.
The result is a detailed report that allows for the establishment of precise rehabilitation strategies, effectively prioritizing repairs and optimizing available resources.
External Corrosion Direct Assessment (ECDA)
The ECDA process is a proven alternative to smart pig inspection, especially suitable for pipelines that cannot be inspected with that method due to operational or design limitations. It is developed in four phases:
- Initial phase: Comprehensive review of historical and current data (design, construction, operation, maintenance, and previous inspections). The feasibility of ECDA is determined, priority areas are identified, and indirect inspection techniques to be applied are defined.
- Indirect inspections: These are carried out along the pipeline’s route using two or more complementary techniques, providing a global view of the coating’s condition and cathodic protection.
- Direct inspection: Based on the previous results, excavation points are selected, and coating defects, corrosion areas, and the performance of protection systems are directly evaluated.
- Final evaluation: Integrated analysis of all data to determine the frequency of ECDA reapplication and define the long-term maintenance and monitoring plan.
Alternating Current Voltage Gradient (ACVG)
Complementary technique to DCVG for detecting coating defects under specific conditions, especially useful in pipelines with AC interference or in environments with high soil resistivity.
Estudios de corrientes vagabundas
Stray currents —generated by electric traction systems, high-voltage lines, or other installations— can drastically accelerate the corrosion of metal pipelines. We conduct stray current measurement and analysis studies to identify their origin, quantify their impact, and propose corrective measures.
Soil resistivity and pH analysis
Soil resistivity is a determining factor for the design and evaluation of cathodic protection systems. We measure resistivity in the field using standardized techniques (Wenner, Schlumberger) and complement it with pH analysis to characterize the aggressiveness of the environment on buried infrastructures.
Pipeline locating
Buried pipeline localization service using electromagnetic techniques, essential for ensuring safety in excavations, updating as-built plans, and planning coating inspections along the actual pipeline route.
Coating surveys (depth)
Evaluation of pipeline coating thickness and depth, in order to complete asset characterization and facilitate the planning of maintenance interventions.
PROCAINSA
Our inspection process
Each infrastructure inspection project follows a structured methodology that ensures traceability and the quality of results:
- Preliminary study: Review of technical documentation, inspection history, design data, and condition of the existing cathodic protection system.
- Planning: Selection of techniques, definition of priority sections, coordination with the client, and obtaining permits.
- Fieldwork: Execution of inspections by NACE certified technicians, with GPS geolocation of all detected defects.
- Analysis and classification: Data processing, classification of defects by severity and electrical behavior, integration with other parameters (resistivity, pH, stray currents).
- Technical report: Delivery of a detailed report with defect maps, severity classification, cathodic protection evaluation, and prioritized recommendations for action.
PROCAINSA
Why trust Procainsa for the inspection of your infrastructures
- More than 35 years of experience in inspection and protection of industrial infrastructures (since 1988).
- NACE certified technicians, the international reference standard in corrosion engineering.
- GPS geolocation technology integrated into all fieldwork.
- Multi-technique approach: we combine DCVG, CIPS, ECDA, and complementary techniques according to the real needs of each installation.
- International presence: projects in Europe, North Africa, and South America.
- ISO 9001:2015 and ISO 45001:2018 certifications that guarantee quality and safety in all our processes.
- Actionable reports: we don’t just detect; we prioritize and recommend, facilitating decision-making and optimizing the maintenance budget.
Frequently asked questions about infrastructure inspection
What is infrastructure inspection in the industrial context?
In the industrial sector, infrastructure inspection is the set of techniques and procedures that allow evaluating the real condition of critical installations —buried pipelines, cathodic protection systems, coatings— without the need for excavation or facility shutdown. The objective is to detect defects, estimate the remaining useful life, and define maintenance priorities based on objective data.
What is the difference between DCVG and CIPS?
These are complementary techniques with different objectives. DCVG locates and quantifies defects in the pipeline coating, expressed as a percentage of voltage gradient (%IR). CIPS evaluates the effectiveness of the cathodic protection system along the entire route, recording on/off potentials at regular intervals. Applied jointly, they offer a complete view of both the coating condition and the protection effectiveness.
What are the advantages of ECDA over smart pig inspection?
The ECDA process is an especially useful alternative when intelligent pigging (ILI) is not viable due to design limitations, diameter, access, or operational conditions. It does not require service interruption or facility modification, and it provides information on the electrical behavior of the coating and the effectiveness of cathodic protection that pigging cannot offer. Both techniques are complementary and, in many cases, are used in combination.
How often should buried infrastructure inspections be carried out?
The frequency depends on multiple factors: the applicable reference standard (ISO 15589, NACE SP0169, etc.), environmental conditions (soil resistivity, presence of stray currents), the installation history, and the results of previous inspections. As a general reference, indirect inspections (DCVG/CIPS) are usually carried out every 3-5 years on high-pressure pipelines, although the integrity plan for each asset must define the specific periodicity.
What regulations govern the inspection of buried pipelines in Spain?
The main regulatory references are Royal Decree 919/2006 (Technical Regulation for the Distribution and Use of Gaseous Fuels), Royal Decree 840/2015 (petroleum installations), UNE-EN ISO 15589-1 and UNE-EN 13509 standards on cathodic protection, and the international standards NACE SP0169 and NACE SP0502 (ECDA). Depending on the type of installation and the fluid transported, additional sectoral regulations may apply.
What does the inspection report include?
The technical report includes: description of the work performed and techniques applied, georeferenced mapping of detected defects, classification of each defect by electrical severity (%IR), cathodic or anodic characterization, evaluation of the effectiveness of the cathodic protection system, complementary data (resistivity, pH, stray currents if applicable), and prioritized recommendations for action with technical and economic criteria.
Can in-service pipelines be inspected without interrupting operation?
Yes. Indirect inspection techniques —DCVG, CIPS, ACVG, ECDA— are performed on the pipeline’s route from the surface, without the need for shutdown or excavation. Only the direct inspection phase of the ECDA process requires selected excavation points, which are planned in coordination with the client to minimize operational impact.