Eliminate BIAS in Silver Corrosion Ratings

Sensors in modern automative fuel systems often use silver or silver alloys, which are susceptible to corrosion from sulfur in gasoline. In the past decade, refiners have shifted to producing low-sulfur gasoline, but the process requires more severe hydro-treating that destroys naturally occuring compounds that give some protection against sulfur-based corrosion. 

Ensuring that fuel stays within acceptable limits requires constant and accurate testing. Unfortunately, modern testing methods rely heavily on user bias, as the operator must evaluate corrosivity by interpreting the color and tarnish level of a of silver strip after it has been bathed in a fuel sample.

AgDDI, from Ayalytical Instruments (USA), uses a four-step automated vision algorithm and classification process to eliminate user bias. After evaluating the silver strip for corrosivity, the algorithm assigns the sample an integer between 0 and 4, with 0 being no corrosion at all and 4 showing significant blackening. AgDDI provides standardization to the current visual determination as referred in ASTM  D7671 and gasoline fuel specification ASTM D4814.