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1. If a seamless solution cannot be adopted, the structure should be designed to facilitate proper drainage. When sediment appears, it should be removed promptly, or the gaps should be filled with solid filler. For example, in stainless steel equipment used in seawater, a lead-tin alloy can be used as a filler; in addition to filling the gaps, it can also act as a sacrificial anode. 2. Design reasonably to minimize gaps as much as possible. Welding must avoid weld holes ； For the screw joint structure, low-sulfur rubber washers can be used, and the joint surface can be protected with a coating. Under normal circumstances, welding is superior to riveting ； Butt welding is superior to lap welding. During design, areas where water can accumulate should be avoided, and regular cleaning should be carried out to remove dirt during maintenance. 3. Apply a coating containing a corrosion inhibitor to the joint surface. For example, for steel, a coating containing PbCrO4 is used ； For aluminum, use a coating containing ZnCrO4 ； For metal sheets, they can be separated using packaging paper soaked in a vapor-phase corrosion inhibitor. 4. Use cathodic protection. When gaps cannot be avoided in the design, cathodic protection can be used. In seawater, a sacrificial zinc or magnesium electrode is used. When using this method, attention must be paid to the issue of hydrogen embrittlement (hydrogen embrittlement occurs when hydrogen dissolved in steel aggregates into hydrogen molecules, causing stress concentration that exceeds the steel’s strength limit and resulting in the formation of tiny cracks within the steel). Hydrogen embrittlement can only be prevented, not cured. Once hydrogen embrittlement occurs, it cannot be eliminated). 5. Use appropriate materials instead. For certain critical components, materials with stronger resistance to crevice corrosion can be used, such as stainless steels with high chromium and molybdenum contents. 6. Adopt electrochemical protection method. If cathodic protection is used, the potential should be maintained within a range that is below the breakdown potential and above the protection potential.