This paper examines the relationship between stress corrosion cracking (SCC) threat modeling and the number of digs required to conclude that a pipeline is SCC free. Results show that when a reliable inspection prioritization model is used, few digs are required to infer that a pipe has a low probability of SCC.
The use of High-Velocity Thermal Spray (HVTS) technology has been well adopted for sour conditions; particularly where low, or locally low, pH conditions result in corrosion and shell thinning. High alloy systems resistant to low pH or acidic conditions are effective at providing a metallurgical barrier, protecting the underlying substrate from material loss. Moreover, HVTS processes have also been employed for mitigating environmentally induced cracking (EIC) in sour service. This paper discusses the suitability and performance of modified HVTS alloys for service where high pH general corrosion or caustic cracking (CSCC) may occur. Extensive testing has been undertaken in both ambient and high pressure and temperature autoclave conditions to better understand material performance in caustic environments. While Nickel Alloy 200 and Monel 400 may be deemed appropriate based on traditional material selections, thermal spray process considerations in the material deposition and the impact of ancillary elements in the process stream, such as halides, render these alloys unsuitable. More complex Nickel alloy cladding systems are evaluated in this study with suitable material recommendations for remediation without the deleterious heat impact of welding or to protect surfaces where heat affected zones have been created and post weld heat treatment is problematic.
New for 2018! This NACE International state-of-the-art report contains information about materials that provide a corrosion-resistant alternative to plain carbon steel reinforcing bar (rebar). The report is intended for use by engineers when considering the use of alternative concrete reinforcement and post- or prestressing strand materials with higher corrosion resistance than that of conventional carbon steel alloys.
To restrain the failure of plate heat exchanger in customer boiler working fluid, the effect of crevice former type on the corrosion behavior of Type 316L (UNS S31603) stainless steel plate was investigated using electrochemical methods and surface analysis in chloride-containing synthetic tap water.
The purpose of this NACE International technical report is to provide basic information regarding the mechanisms involved with cathodic protection (CP) shielding for external coatings applied to carbon steel pipelines, and the manner in which the breakdown of coating systems may or may not contribute to CP shielding. It is intended to be a basic reference from which the tendency of a coating system to fail and shield CP may be understood on a conceptual basis. Non-corrosion-related pipeline protection systems, including concrete weight coating, polyethylene encasement, insulation, and mechanical pipeline protection systems, are outside the scope of this report. End users of this report may include pipeline designers, corrosion engineers, integrity management specialists, regulators, CP service providers, coating suppliers, coating service providers, equipment suppliers, and pipeline/facility owners.