Analisis Laju Korosi dan Lifetime Pipa Underground Baja Karbon A53 dengan Wrapping Protection
Reclaimed soil condition at PT.XYZ area is corrosive soil because it contains acid and has high salinity. Based on the condition, wrapping coating is not giving enough protection to the material from corrosion defect. A research would be carried out to find the best corrosion protection for underground pipe in this area. The first step taken was to compare the corrosion rate and lifetime between wrapping coating and painting+wrapping coating. The material used was A53 carbon steel. The calculation of corrosion rate used weight loss method described in ASTM G31-72 (Standard practice for laboratory immersion corrosion testing of metals). Immersion testing was performed for 720 hours with various pH and NaCl concentration adjusted with soil sheet. The lifetime calculation was based on API 570 standard. From the calculation of corrosion rate, the average result of both coating, 0.003561 mm/y for painting+wrapping coating, and 0.008324 mm/y for wrapping coating are obtained. While the average lifetime value for painting+wrapping coating is 258.778 years and 109.93 years for wrapping coating. Thus the best corrosion protection for hydrant underground pipe with corrosive soil is by using painting+wrapping coating protection because it has longer lifetime.