How calcareous deposits formation in seawater influences the performance of a galvanic cathodic protection (CP) system in seawater. Coupling current measured. A resistance set between the cathode and the anode simulated circuit resistance of CP. Steel cathode potential over immersion time. Calcareous deposits analyzed by X-Ray Diffraction.
An advanced grade of super-austenitic stainless steel with a reduced content of nickel offers a significant economic advantage over nickel-base CRA’s. As the alloy is readily fabricated by conventional techniques, it is an excellent candidate for a variety of applications in the chemical, petrochemical, mining, oil and gas, and refining industries.
Experience has shown that stainless steels can suffer from Hydrogen Induced Stress Cracking (HISC) under cathodic protection in seawater. This paper presents results from a test program examining the HISC susceptibility of 25% Cr super duplex stainless steel (UNS S32750) at temperatures up to 1500C.
Superduplex stainless steels have been used in seawater systems since 1986 as castings and since 1990 as wrought product. The present paper describes some of the service environments commonly in use and the conditions that give rise to specific operating potentials. The limits of use under these conditions are described utilizing both laboratory and service experience.
Evaluation of metal-based structures has relied on atmospheric exposure test sites to determine corrosion resistance in marine environments. This work uses surface chemistry and electrochemical techniques to interpret the chemical changes occurring on low carbon and stainless steel during atmospheric and accelerated corrosion conditions to find a correlation between its accelerated and long-term corrosion performance.
This paper presents an expanded laboratory test database on critical corrosion modes for UNS R55400 pipe exposed to relevant oilfield production environments which include sour well fluid brines, a heavy chloride/bromide brine well completion fluid, injected methanol, organic acid- and HCl-based well acidizing solutions, and seawater.