When it comes to a bridge structure with a serviceable Organic Zinc / Epoxy / Urethane (OZ/E/U) coating system, there is no golden answer on the most cost-effective maintenance painting strategy. Depending on the severity and amount of corrosion and coating breakdown on the structure, planned maintenance surface preparations range from spot power tool cleaning and spot painting to a full SSPC-SP 10 media blast and full recoating operation.
In the oil and gas industry, thermally sprayed aluminum (TSA) coatings are commonly used, primarily, to reduce anode demand in cathodic protection systems and impart some degree of sacrificial protection in the topsides and splash zone areas. The use of TSA coatings has advantages in systems where long service life is required. TSA coatings are also used to reduce the formation of calcareous deposits, normally a combination of CaCO3 and Mg(OH)2, on heat exchanger piping.
The prevention of internal corrosion remains a significant challenge during the production of oil and gas. The use of film forming corrosion inhibitors is an important and cost-effective means of protecting assets from corrosion. These chemicals operate by forming a protective layer between the corrosive species present in the produced fluids and the pipe surface.
Inorganic fouling in oilfields has resulted in millions of dollars of operating expenditure every year since the inception of offshore oil and gas drilling, where mineral scale deposition in tubing, flowlines and downhole equipment leads to significant production downtime. Calcium carbonate (CaCO3) fouling is endemic in oilfield systems, as produced water containing both bicarbonate and calcium ions is prone to form precipitates as a result of pressure changes during production.The release of carbon dioxide gas from the aqueous phase prompts the evolution of carbonate resulting in a rise in pH and consequent precipitation.
A substation is a place where the power system converts voltage and current and receives and distributes electric energy. When a phase line is abnormally connected to another phase line or ground, a large amount of current will flow into the ground through the grounding bed of the substation. In such case, if metal structures exist such as buried pipelines near the substation, the pipelines often withstand serious electrical interference 1, which causes stray current corrosion of the pipelines 2 and other safety problems.
An energy company hired a contractor to remove and replace the linings of water box condensers during a maintenance shut down. This case history will give a summary of the scope of work, a review of the specification, a description of the work performed, an accounting of the in-process inspection, and a summary of lessons learned during the project.
Aboveground storage tanks (ASTs) are assets that contain valuable goods for the oil and gas industry. Consequently, monitoring and preventing loss of containment and extending the service life of those assets is a priority for the abovementioned industries. To monitor the degradation process of the tanks, ER probes are typically used to determine the corrosion rates. Corrosion rates can be used to forecast the service life of an asset by estimating the time at which the degradation reaches a critical thickness of the tank. If the corrosion rate is such that the critical thickness is expected to reach below the expected service life of the asset, the lifespan can be extended by corrosion mitigation methods.
AC interference analysis between high voltage AC (HVAC) powerlines and buried pipelines is a matter of current interest due to the growing number of right-of-ways shared between powerline and pipeline infrastructure. This is only expected to increase as the worldwide energy demand grows considerably over the next 30 years,1 and stricter environmental regulations and policies are applied. Therefore, AC interference will continue to be an issue of concern for powerline and pipeline operators to protect the public, environment, and maintain asset integrity.
Coatings are a composite blend of raw ingredients that are mixed, applied to a prepared substrate, and dried and cured correctly to perform to their maximum capability. Failures and defects can appear themselves at numerous times in the life of a coating. Prior to application, they can take the shape of settlement and skinning, during application as runs and sags, shortly after application as solvent popping and orange peel, and during service as blistering and rust spotting. Therefore, it is not unexpected that those coatings can suffer from premature failure and/or exhibit defects that may or may not result in failure. Coatings nowadays are the most efficient method to shield metals and thus has been widely engaged among various protective techniques 1, 2.
Plant assets for hydrocarbon and power generation systems are prone to numerous damage mechanisms that arise from operating and/or upset conditions, environmental factors, material defects as well as other neighborhood factors 1-2. Corrosion is one of the key degradations that pose a substantial economic burden, and may result in severe safety and environmental hazards 3. While considering the percentage for global economy in terms of corrosion, the total cost of corrosion globally amounts to ∼2.5 trillion US dollars per year. Among the corrosion mitigation measures, organic protective coatings are the most widely used, and their costs add up to two-thirds of all anti-corrosion overheads 4.
EN Engineering (ENE) completed an AC interference study over 68 miles of an operator’s transmission line. In addition, an ACVG survey of approximately one (1) mile of the pipeline was conducted at the take-off point of the 8” line. As a result of this AC interference study, evidence of elevated AC corrosion risk has not been found on the operator’s pipeline. However, a review of the provided data shows evidence of DC interference due to a nearby foreign rectifier groundbed at the take-off point of the operator’s line.