If all three conditions are met, intergranular cracking can initiate and propagate through the pipe or vessel wall within a matter of hours, leading to catastrophic structural failure upon restarting the unit. Core Mitigation Strategies in NACE SP0170
The standard provides four primary mitigation methods, which can be used individually or in combination depending on a facility's specific risk assessment. According to the standard's scope, these methods are listed in its Paragraphs 1.3.1 through 1.3.4. nace sp0170 pdf
Using heated dry air to ensure the relative humidity is below the dew point, preventing liquid water from forming on the surface. If all three conditions are met, intergranular cracking
In some scenarios, maintaining a continuous purge of extremely dry air (with a dew point typically below -40°C/-40°F) is acceptable. Keeping the relative humidity near zero prevents the chemical reaction required to generate the acid. Material Selection as a Long-Term Solution Using heated dry air to ensure the relative