Excessive corrosion in process piping and vessels can lead to serious safety, environmental, and economic damage for manufacturers and producers. Global bodies such as NACE International and the American Petroleum Institute provide standards and best practices to help mitigate the effects of corrosion.
In an Oil & Gas article, Using NACE standards to protect against corrosion, Emerson’s Ali Babakr and David Macedonia describe ways to effectively comply with the standards to better address corrosion risks.
Ali and David open highlighting the problem:
Corrosion is the scourge of the oil and gas industry worldwide, eating up maintenance budgets and often causing incidents. The term corrosion comes from the Latin word corrodere, which means “to gnaw to pieces.”
From a safety perspective, in a:
…European Commission study of refining accidents around the world traced to corrosion, 76% resulted in fires or explosions.
They cite other statistics such $2.5 trillion or 3% of global GDP as the economic cost of corrosion. These costs include:
…inspections during outages, replacement of corroded piping and components, installation of corrosion-resistant components in new systems, and the damage caused from corrosion-related incidents.
The NACE/ISO standard, NACE MR0175/ISO 15156:
…provides metallurgical requirements for carbon steels, low alloys, and corrosion-resistant alloys with respect to chemistry, hardness, heat treatment, and hydrogen induced cracking resistance.
…places “environmental restrictions” or “environmental limits” on almost all corrosion resistant alloys, which are essentially everything other than carbon steels and low-alloy steels. These limits are typically expressed in terms of partial pressure of the corrosive agent, maximum temperature, ppm chlorides, and the presence of free sulfur.
End users are:
…responsible for selecting suitable materials for the application and documenting the desired process media parameters.
Their suppliers are:
…responsible for making sure the user’s chosen material meets the metallurgical and manufacturing requirements and complies with any applicable testing requirements, and for complying with marking and documentation requirements.
Read the article for more on some of the alloys to help address the standards and mitigate the risks associated with excessive corrosion. Visit the Valves, Actuators & Regulators and Corrosion & Erosion Monitoring sections on Emerson.com for more on selecting the right allows and performing real-time corrosion monitoring for early warning of excessive corrosion.