The primary corrosiveness of crude oils and destructions of metals

Metals play predominant prefaces regarding most of industrial components such as the crude oil refining industry although corrosion performed some banes. In the current research it was expected to investigate to compare the effect of corrosive properties of two different crude oils on the rates of corrosion in seven different types of ferrous metals. The contents of sulfur, mercaptans, organic acids, salt in both crude oils and chemical compositions of ferrous metals were determined by standard methods and instruments. A batch of similar sized metal coupons was prepared and immersed in both crude oils separately. The corrosion rate of each metal coupon was determined by the weight loss method in order to after 15, 30 and 45 days while observing the corroded metal surfaces by the optical microscope. The decayed concentrations of copper and ferrous in each crude oil sample were tested and the both initial and final hardness of each metal coupon were tested. According to the results there were observed lower corrosion rates from stainless steels, relatively higher impact from salts on the corrosion, formation corrosion compounds, corrosion cracks, pitting corrosion on metal surfaces and there were observed a slight reduction of hardness in each metal coupon eventually.