Investigating the Corrosion under Insulation (CUI) on Steel Pipe Exposed to Arabian Gulf Sea Water Drops

Abstract

This paper is an endeavor to investigate an insulated mild steel pipe that exposed to three sea water drops rate (10, 30, and 50 drops/minute) at room temperature. Various experimental strategies were employed including visual inspection; scanning electron microscopy (SEM) with EDAX. After removing the insulation material, it was observed that pipes were corroded. However, the extent of corrosion was varied which was attributed to the drop rates, it was revealed that corrosion process was initiated due to water and ions penetration through the insulation, such revelation highlighted the necessity to properly examine the pipe and the insulating material. Results also revealed that severity of corrosion is proportional to the drops rates. EDAX analysis of the pipe surface and the insulating material shows the presence of difference ions including Na+, Cl-, Mg2+, Si2+ and others, the results highlighted the importance of material selection and the necessity for early detection strategy in order to avoid catastrophic failure.

In Situ Monitoring of Corrosion under Insulation Using Electrochemical and Mass Loss Measurements

“…The small values of the R film for CS over time indicate that the corrosion products on the surface were porous, nonprotective, and easy to peel off. This phenomenon was reported in other publications and was also observed after the setup was disassembled [5,34]. The decrease in R f ilm of SS can be attributed to the breakdown of protective films formed on the surface.…”

“…CW led to a higher gradient of reduction in polarization resistance than in the case of IW over the testing period. Furthermore, the oxide film resistance of both CS and SS declined faster under cyclic conditions, suggesting that the corrosion product or film became more porous and nonprotective (4) The surface characterization illustrated that the accelerated CUI by thermal cycling originates from the deterioration of oxide layers and localized corrosion (5) The unique Pt(Ti) sensing method has demonstrated its ability to in situ evaluate the resistance and the corrosion rates of substrate materials and/or protective film with time and cyclic temperature. Due to its accuracy, robustness, and economic advantages, it is practically possible for being installed in petrochemical, refining, offshore, and marine/maritime industries to assist target inspection activities (i.e., on piping, vessels, and tanks).…”

“…The progression of CUI involves many factors, including insulation types, coating materials, substrate materials, and operating conditions [4,5]. Among these factors, extensive efforts were made to select the optimum insulation and/or coating materials with excellent CUI resistance in various service environments, while the stability/durability of substrate materials under various operating conditions still requires further investigation [6][7][8][9][10].…”

Analysis of Temperature Variations, Types of Insulation and Coating on Corrosion Under Insulation on ASTM A53 Pipes

“…Corrosion under insulation is a very serious problem for the oil and gas industry using piping systems [8] [7]. The most challenging problem of this type of corrosion is that the corrosion structure that occurs is not visible or covered by insulation, therefore to avoid corrosion so that it is not too severe choosing the type of insulation material is very important [9]. Conducted a study to analyze the type of insulation for the hot steam transmission pipe for a motorcycle tire cooker with a capacity of 2000 tires per day at PT.…”

“…Conducted a study to analyze the type of insulation for the hot steam transmission pipe for a motorcycle tire cooker with a capacity of 2000 tires per day at PT. XYZ in Tangerang [9] [10]. In this study, quantitative methods were used to compare the types of insulation based on the existing theory of insulation conditions.…”