Study on corrosion properties of four casing materials in produced water of Luohe sandstone layer

Abstract Casing corrosion failure has been a major technical problem in oilfield development since exploitation. In this paper, the corrosion behavior of four common casing materials (J55, P110, N80 and N80Q) under the service environment of produced water in Luohe sandstone formation was studied by using water quality analysis, corrosion simulated weight loss experiment and corrosion electrochemical test. The results show that the produced water in Luohe bed is sodium sulfate water with high oxygen content and erosive carbon dioxide, which are the main causes of corrosion. According to the NACE RP0775 standard, the corrosion rates of the four casing materials belong to severe corrosion, and the corrosion rates meet the requirements of P110 > J55 > N80 > N80Q. The results of electrochemical polarization curve and AC impedance spectrum are in agreement with the corrosion rate relationship reflected in the high pressure corrosion simulation test.