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1. If a seamless solution cannot be adopted, the structure should be designed to facilitate proper drainage. When deposits occur, they should be removed promptly, or the gaps should be filled with solid filler. For example, for stainless steel equipment used in seawater, a lead-tin alloy can be used as filler; besides filling the gaps, it can also serve as a sacrificial anode. 2. Design reasonably to minimize gaps as much as possible. Welding must avoid weld holes ； For screw joint structures, low-sulfur rubber gaskets can be used, and the joint surfaces 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; during maintenance, regular cleaning to remove dirt is necessary. 3 Apply a coating containing a corrosion inhibitor on the joint surface. For example, for steel, use a paint containing PbCrO4 ； 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. Cathodic protection is employed. When gaps cannot be avoided in the design, cathodic protection can be employed. In seawater, sacrificial zinc or magnesium electrodes are used. When using this method, attention must be paid to the issue of hydrogen embrittlement (hydrogen embrittlement occurs when hydrogen dissolved in steel combines into hydrogen molecules, causing stress concentration that exceeds the steel’s strength limit and results 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. 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 Electrochemical protection method is adopted. If cathodic protection is used, the potential should be maintained within a range that is below the breakdown potential and above the protection potential.