If steam is injected into a vessel, which area is most susceptible to corrosion?

In pressure vessels where steam is injected, the area most susceptible to corrosion tends to be the vessel wall opposite the nozzle. This is primarily due to several factors that contribute to the corrosive environment in that specific area.

When steam enters a vessel through a nozzle, it can create a temperature gradient within the vessel. The nozzle area may experience higher temperatures while the opposite wall can be relatively cooler, especially in cases of improper insulation or heat distribution. The temperature difference can lead to condensation of steam, which introduces moisture into the environment and can facilitate corrosion processes.

The condensation of steam not only results in the presence of water but may also carry dissolved minerals and contaminants, further contributing to corrosive conditions. This moisture can accumulate on the vessel wall opposite the nozzle. Additionally, if there are any contaminants in the steam, they can settle on this surface and exacerbate the corrosion process, making this area particularly vulnerable.

The other areas, like the nozzles, bottom head, and top head may also experience some level of wear and corrosion, but the combination of temperature gradients, moisture accumulation, and potential contaminants leads to the wall opposite the nozzle being the most susceptible location for corrosion in this scenario.