How To Prevent Gap Corrosion of Stainless Steel Pipe?

Due to the gaps in the equipment and component structures or the presence of metal or non-metallic deposits on the surface of stainless steel pipes, gaps are formed between the deposits and the surface of the stainless steel pipes. Under the action of corrosive media, punctate and ulcerative damage will appear before the crevice, which is crevice corrosion. In the presence of water media such as Cl-, due to the acidification of the medium solution in the gap (increased Cl- concentration, decreased pH value) and lack of oxygen (oxygen concentration difference battery, lack of oxygen in the gap).

How To Prevent Gap Corrosion of Stainless Steel Pipe?

1. The most fundamental way to eliminate gap corrosion is to avoid the existence of gaps in structural design, and take corresponding measures to prevent the gaps between the heat transfer equipment tubes and the tube sheets, and the gaps between flanges, washers, bolts, and rivets.

2. Clean regularly and maintain the flow rate ≥1.5m/S in seawater and other environments to prevent dirt (including marine organisms) from accumulating on the surface of stainless steel pipes.

3. Use high chromium, molybdenum and high chromium, molybdenum and nitrogen stainless steel pipes for crevice corrosion.

In general, to solve crevice corrosion, it is more difficult to start with model selection than to solve pitting corrosion, and the economic cost will be higher.