Methods for cathodic inhibitor evaluation in neutral cooling water systems

Water-soluble corrosion inhibitors are acknowledged as the most effective and cost-efficient method for protecting mild steel cooling water systems. However, before an inhibitor is used, its effectiveness must be ascertained. This is usually accomplished using long term rig tests. These are simplified, scaled down versions of industrial systems, in which cooling water conditions are closely simulated. Corrosion rates are calculated from weight loss measurements. These take weeks or even months to complete. Hence with shorter product deadlines, rig tests often prove too lengthy to satisfy commercial pressures. [Continues.]