What is under-scale corrosion in equipment?
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Dear friends: What is underfilm corrosion, and how can it be eliminated? Please explain (images would be ideal). Thank you
The above information was obtained from Baidu. From my personal perspective, scaling is a prerequisite for corrosion; by reducing the presence of scale, such corrosion degradation will **decrease**. In addition to the conventional pickling process used to reduce corrosion damage on the inner surface of metals, there is also an ultrasonic scale inhibitor – I’m not sure if you are aware of it. The performance has been really good over time, and there is little need for manual maintenance – it’s a user-friendly device. Those who are interested can search on Baidu by themselves!
This post was last edited by Shutong on 2020-7-9 at 12:07. I agree with the administrator’s explanation; to add more, scale is a deposit that forms directly from aqueous solutions and adheres to metal surfaces. Salt scale: Solid deposits formed by the precipitation of salts (impurities) present in boiler steam within thermal equipment. Slag: Deposits that form in the furnace water and remain suspended within it. All these messy substances undergo chemical or electrochemical reactions with metals, which leads to corrosion beneath the scale
:) Learned it – the explanation of scaling and corrosion is thorough!
President Li: Can corrosion beneath boiler scale be understood as alkaline corrosion? However, boilers are generally treated with alkaline chemicals, and the cause of corrosion beneath the scale in these boilers is not clear; please advise.
Silicates cause scaling in heat exchange
The formation of corrosion is related to the accumulation of scale; whether acidic or alkaline substances are added to the medium, they remain around the persistent scale, and over time this leads to corrosion beneath the scale. Eventually, this results in equipment perforation. To prevent corrosion, it is necessary to first prevent scaling, and when the equipment operates without scale, there is no risk of corrosion.