Wear of Small Orifices by Streaming Current Driven Corrosion

Abstract

Wear on the upstream side of small metal orifices subject to large pressure drops (3000 psi) in phosphate ester base hydraulic fluids has been found to be the result of an electrochemical corrosion driven by a streaming current. A calculation for the current produced by the flowing fluid is described. Results of the calculation and of experimental work are given as evidence in support of the proposed wear mechanism. A large variation of wall shear stress along the metal surface is found to be necessary for the wear.