1) Improve the surface treatment process of
fasteners. According to the test results, the corrosion resistance of cadmium plating in the marine environment is significantly better than the galvanizing process. Therefore, the washers and bolts that originally used the galvanizing passivation process were changed to the cadmium plating passivation process for surface treatment.
2) The
fastener hole wall surface protection. For the hole walls of aluminum alloy structural fasteners without surface treatment, use Alodin for surface treatment, and then apply a layer of anti-corrosion primer; for the hole walls of steel structural fasteners without surface treatment, apply a layer of phosphorus The primer.
3) Wet assembly of
fasteners. After the fastener hole wall primer is cured, the fastener is wet-assembled with grease. The assembly with grease can not only play a sealing role, prevent the medium from infiltrating into the gap, but also the fasteners are easy to disassemble, which is convenient for field construction.
4) Spray corrosion inhibitor. After the fasteners are assembled, a layer of soft film water displacement corrosion inhibitor is sprayed on the surface of the fastening connection area. Corrosion inhibitor is an important means of corrosion prevention and control. It has good permeability and water displacement. It can quickly penetrate into the crevices of the aircraft structure, replace the water in the gaps and the metal surface to the outside, and isolate the metal from water. At the same time, a protective film is deposited on the metal surface to effectively delay the corrosion of metal materials.
In conclusion:
1) By taking comprehensive protective measures for surface protection and assembly and sealing, it can effectively solve the corrosion problem of the steel fastening connection area that is frequently disassembled.
2) Protective measures such as painting the wall of
fastener holes and supplementary spraying of corrosion inhibitors after assembly can be used as reference in the design and repair of corrosion protection of other connecting structures.
