Discuss the electrical insulation principles and failures related to corrosion control in oil and gas facilities

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When pipeline structures are susceptible to galvanic corrosion or corrosion caused by alternating and direct current interference currents, a practical method for corrosion control is to ensure the electrical isolation of the structure. Piping system design should avoid using dissimilar metals in locations where they are in direct contact or pass through the same electrolyte. When using dissimilar metals, electrical isolation measures must be employed to break the electrical continuity of the metals in order to prevent or significantly reduce galvanic corrosion. Stray current is not the galvanic corrosion current between an anode and a cathode of the same structure. Current flowing through electrical paths other than the normal circuit can be classified as stray current, including static current or dynamic current, alternating current or direct current. Stray currents cause severe corrosion in most metals. Stray current corrosion can be caused by systems such as power systems, railway systems, electrical grounding, cathodic protection systems for adjacent buried pipelines, mining operations, welding operations, etc. If left uncontrolled, stray currents can quickly damage structures or lead to potentially catastrophic consequences.