2. Do you know how to clean and passivate stainless steel facilities?

8. Application examples

　　8.1 Passivated long series

When the long series of parts are passivated, the upper and lower ends of the plated parts enter and exit the passivation solution sequentially. At the same time, when the workpiece swings in the solution, the swing amplitude of the lower end of the plated part is much larger than that of the upper end; on the other hand, after passivation in the air When it stays in the middle, the solution flows from the upper end to the lower end. The surface of the lower plated part has more solution than the upper plated part, and the lower end has more chemical reaction time with the solution. All these make the passivation film on the lower end darker than the upper end. In order to reduce chromatic aberration, it is recommended that such parts enter and exit the passivation solution horizontally (the lower end is hooked up with a hook), and to prevent the anode from being used too long.

　　8.2 Long parts passivation

When the long parts are passivated, if the passivation tank cannot be accommodated, temporary measures can be taken. Use bricks or wooden strips to process a frame that can accommodate the plated parts. The frame is lined with plastic cloth and can be used after injecting the passivation solution. Adopting this method is convenient and can avoid quality problems such as uneven film or production of joint marks.

　　8.3 Plane parts passivation

Generally, when flat parts are passivated, the edge part and the passivation solution will be in contact with the passivation solution more intensely than the middle part when swinging in the passivation tank, which causes the uneven color of the passivation film at this part. This problem can be solved by stirring with compressed air. ,good results. In order to improve the uniformity of the passivation film, it is also necessary to pay attention to the uniformity of the current distribution during the galvanizing process. If necessary, the edge of the plated part should be shielded to prevent the roughness of the coating due to excessive current and affect the color of the passivation film.

　　8.4 Surface passivation

After passivation of the surface finish part, because the surface is smooth, the passivation solution is more difficult to adsorb on the surface and will be lost quickly. Therefore, the residence time in the solution and in the air during passivation must be appropriately extended, otherwise the passivation film of the workpiece It looks lighter.

　　8.5 Easy to pocket water passivation

　　 It is necessary to avoid taking out the solution, so as not to cause excessive damage, consumption, and environmental pollution of the passivation solution, and also to protect the quality of the passivation film in this part.

　　8.6 Small pieces passivation

　　The whole string of strapped workpieces can be passivated in a plastic basket, so as not to fall out of the group due to jitter during passivation and fall into the groove to cause repair.