Investigation of Corrosion Resistance Welds Metal Hose Made of Steels AISI 304 and AISI 316

Despite a large number of available data regarding the causes of damage of steel structures made of stainless steel of AISI 304 and AISI 316 grades, little attention has been paid to the manufacturing and storage conditions of these steel grades, but these conditions may be additional factors promoting pitting corrosion and other types of local corrosion. The article describes the results of researches aiming to increase corrosion resistance of welded steel flexible hoses for transportation of natural gas made of austenite steel. The research determined the controversial influence of the deformation degree on the tendency to corrosion failure of stainless steel; showed the efficiency of heat treatment of AISI 304 and AISI 316 steels to relieve internal stresses in order to increase their corrosion resistance. As a result, in order to reduce propensity for corrosion cracking (pitting) of welded steel flexible hoses is recommended to perform the heat treatment for stress relief at a temperature of 200 °C for 60 minutes. The suggested technology may be used at various enterprises. The results showed in the article may be useful for the specialists engaged in increasing the life of welded steel structures