Pipelines and Flow Lines

The 12 o clock position in a line is the most difficult part to inhibit. Where the flow velocity is less than required for turbulent flow, liquids will not contact this area except in areas of slug or partial slug flow. Addition of a volatile component to the inhibitor may be required. 

In most cases, free liquid moves along the bottom of the pipe. Depending npon the velocity, the layer may be both condensate and water, or discrete layers of oil and water. At low velocities sohds dropout 

Areas downstream of welds, minor huckhng of the line, low spots, and solids deposits can increase shear stress and turbulence, which may aggravate corrosion. Low spots cause slugs of hquid at intervals. Turbulence removes protective scale, aggravates abrasion and erosion if sohds are present, and may affect inhibitor performance by removing the film. Inhibitors must be able to withstand the shear stresses. 

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