Pengaruh Jenis Coating Terhadap Laju Korosi dan Lifetime pada Pipa SS400 di Lingkungan Air Tanah dan Air Laut

Abstract - Corrosion of pipes generally occurs on the outer walls of pipes due to environmental influences that have a high level of corrosiveness. Underground pipes are located close to sea level so that environmental conditions are mixed between groundwater and seawater. With the addition of coating on the outer wall of the pipe can prevent corrosion events caused by the environment. In this research, the pipe material uses Carbon Steel SS400 with Cold Galvanized coating type protection, Polyurethane and mixtures then use immersion test according to ASTM G-31. The test variable uses a variation in coating thickness of 100 – 350 ?m and the use of solution types, NaCl and H2SO4. Based on the test results, specimens with Cold Galvanized coating thickness of 100 - 150 ?m in H2SO4 solution have the highest corrosion rate value. Meanwhile, the lowest corrosion rate value occurs in specimens with Cold Galvanized + Polyurethane coating with a thickness of 300 – 350 ?m in NaCl solution. Furthermore, from the value of the corrosion rate, a minimum thickness calculation can be made based on ASME B31.8 and remaining life calculation based on API 570 as code & standard used. From these calculations show that Cold Galvanized + Polyurethane coating is the most effective corrosion protection compared to other types of coatings.The lowest lifetime value occurs in specimens with Cold Galvanized + Polyurethane coating thickness of 300 – 350 ?m in NaCl solution, which is 58.99 years. While the highest lifetime occurs in specimens with Cold Galvanized coating thickness of 100 – 150 ?m in H2SO4 solution, which is 23.24 year