An Experimental Study on the Erosion-Corrosion Performance of AISI 1018 Carbon Steel and AISI 304L Stainless Steel 90-Degree Elbow Pipe

Abstract

Erosion-corrosion is an unavoidable material degradation process in flow pipelines transporting abrasive particles with carrier fluids. In this study, the multiphase flow loop apparatus is employed to assess the erosion-corrosion behavior and mechanism relative to AISI 1018 carbon steel (CS) and AISI 304L stainless steel (SS) 90° long radius elbows with the inner diameter of 50.8 mm. Fine silica sand of 50 µm average size was used as a dispersed phase and erosion-corrosion tests were conducted for slug flow conditions. The erosion-corrosion analysis of 90° elbows was determined from its surface morphologies before and after the experiment using confocal and scanning electron microscopy (SEM). The direct mass loss was measured to quantify the erosion-corrosion rate of the elbow configurations. Additionally, multilayer paint modeling experiments were performed to relate qualitative inferences on erosion distribution and location with the erosion-corrosion mechanism. It was observed that the erosion or corrosion pitting mechanism prevailed on the 1018 CS elbow surface, and the 304L SS displayed excellent erosion-corrosion resistance properties. Moreover, the erosion-corrosion rate was found to be 4.12 times more in the 1018 CS compared to the 304L SS with the maximum particle impaction identified at the exit of the horizontal-horizontal (H-H) 90° elbow for slug flow.