For example, CAPCOM inputs for both cased and uncased sections of the pipeline include their dimensions and coating properties, plus soil properties and any electrolytic properties that may exist inside the space between the casing and carrier pipe.
Using the FEM formulation, CAPCOM also can represent varying conditions that affect the carrier pipe, such as how the soil conducts or resists electrical conduction at different locations near the cased portion of the pipeline.
This capability sets CAPCOM apart from other CP models, which use a different modeling approach known as the boundary element method (BEM).
CAPCOM explicitly accounts for electrolytic-plus-metallic contact between carrier and casing pipe and the soil outside the cased crossing to determine the corrosion condition of the carrier pipe.
CAPCOM also includes specifications for modeling "coating holidays"--places where the protective coating is damaged or missing--both inside and outside the cased pipeline section.
With CAPCOM, users can determine the level of CP the carrier pipe will need and evaluate the risk of external corrosion at "holidays" on the carrier pipe inside the casing.
CAPCOM saves costs compared to both visual and inline inspections.
By comparison, analyzing pipelines with CAPCOM software requires only the associated engineering time for the analysis, once the software is purchased.
CAPCOM does require a large number of input parameters to simulate the corrosion conditions of a cased pipeline.
When comparing the CAPCOM model with an inspection, electric potentials predicted by the model (Figure 1) closely match the potentials measured by actual inspection (Figure 2).
Southwest Research Institute's CAPCOM has been recognized by research science and engineering publication R&D Magazine as one of the 100 most significant innovations the past year.
CAPCOM was cited as a cost-effective method of predicting potentially dangerous pipeline corrosion conditions in hard-to-inspect, cased pipeline segments.