Advantage/disadvantage about repairing of pipeline old coating and increasing of CP station

In light of pipeline coating aging problem, puts forward two plans; coating repairing and CP station increasing and makes economic comparison and analysis to the two plans individually. Because of high cost in coating repairing and difficulty to reach construction quality, measures for coating inspection and repairing, partial maintenance and CP station increasing can be applied to prolong coating overhaul cycle and life span when short of capital, which can obtain optimum economic benefit. The article recommends that seven CP stations be installed to drop insulation resistivity of coating down to 200 Ω·m² and below before coating overhaul construction.