ELECTROCHEMICAL EVALUATION OF FLOW ACCELERATED PREFERENTIAL WELD CORROSION OF X65 PIPELINE STEEL USING JET IMPINGEMENT

摘要

Preferential weld corrosion (PWC), enhanced by changes in flow conditions, has been reported in water injection and oil and gas production systems, resulting in the risk of premature failure. The aim of this work was to investigate the suitability of the submerged jet impingement method for the study of flow enhanced preferential weld corrosion and inhibitor evaluation in a typical offshore production system. The novel aspect of the work was the construction of the jet impingement target, which was made of sections from different weld regions, machined from welded X65 pipeline steel. The galvanic currents flowing between the weld segments in each hydrodynamic region were recorded simultaneously using zero-resistance ammeters and their self-corrosion rates were evaluated from linear polarization resistance measurements. The role of hydrodynamics and the influence of typical oilfield corrosion inhibitors on this form of corrosion are discussed.