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Construction elevator fittings stainless steel screw is made by metal, and metal corrosion method mainly has four aspects, namely the nature of the material itself, the use of environment, data and environment of the interface, and improve the design of metal structures, if manufactured complete corrosion resistant alloy to stainless steel screws, unless you have special requirements, or in the economic perspective is not practical, or screw appearance corrosion environment factor is the complete isolation, also does not work in practice, can be very difficult. To prevent the production of corrosion process, or reduce the corrosive medium and metal surface contact, and achieve the purpose of avoiding or reducing corrosion.

The maintenance layer shall meet the following requirements:

1, corrosion resistance, wear resistance, high hardness,

2, the structure is tight, intact, small pores.

3. Solid separation from the base metal and good adhesion.

4. Average dispersion with a certain thickness.