External Corrosion Direct Assessment (ECDA)

Exploring Alternatives to Smart Piston Inspection

Nowadays, the intelligent piston inspection is one of the most reliable tools to know the integrity status of a pipeline. However, it is very common that either due to pipeline design problems, system operation restrictions or simply due to economic problems, the Operator must look for alternatives to the intelligent piston.


Using the ECDA Methodology to Assess the Integrity of a Pipeline

ANSI/NACE SP502-2010 Pipeline External Corrosion Direct Assessment Methodology provides fundamental guidelines for investigating the condition of the pipeline in relation to external corrosion.

Recently, a client approached us with the need to assess the integrity of a pipeline supplying a major customer. However, this pipeline was not suitable for pigging inspection as it was not originally designed for this purpose. The pipeline was buried and had an aerial end section until it reached the customer’s facilities. It should be noted that the product transported was dry gas, which means that there were no concerns related to internal corrosion. In these circumstances, the ECDA methodology proved to be the most suitable for determining the current state of the pipeline integrity.

Phase Startsl – Initial study of the historical and current data of the pipeline: design, construction and commissioning data, operating variables, maintenance and inspection results… where we can find out if the ECDA is feasible, define different areas for ECDA, as well as the inspection techniques to be used.

Indirect Inspections – During this phase inspections will be carried out on the pipeline route. Two or more inspection techniques should be used.

Direct Inspection – The data obtained in the previous phase will be studied in order to select the excavation points. The data from the direct inspection will be combined with the data from the previous phase. Coating defects, corrosions and the performance of the systems against external corrosion will be evaluated.

Final Evaluation – Final analysis of the data from the previous 3 phases and determine the frequency of application of this method.

Pipeline Inspection and Defect Assessment: Experience and Accuracy

At Procainsa SA, we have extensive experience in the inspection of coating failures in pipelines using advanced techniques such as DCVG/ACVG, cathodic protection and CIPS, as well as in the analysis of soil aggressiveness through the evaluation of factors such as resistivity and pH.

Our process begins with thorough indirect inspections and the collection of detailed data. We then conduct a thorough evaluation of this data to identify any defects that require further investigation.

Our experience combined with the accuracy of our inspection techniques enables us to detect and assess defects with a high level of reliability, giving our customers peace of mind that their piping systems are being managed with the utmost care and attention.