Conveyor chain has been widely used in various industries, but it will be passivated in the process of application. What are the causes?
Chlorine ion, medium condition and appearance cleanliness. The content of martensite and chromium nickel in stainless steel conveyor chain has a great influence on the passivation function of stainless steel conveyor chain.
The passivation function of martensitic stainless steel chain plate is lower than that of austenitic stainless steel chain plate. Chloride ion is very harmful to stainless steel chain plate. In the course of passivation, the content of chloride ion in passivation solution should be strictly controlled. The chemical materials used for passivation have limited requirements for chloride ion. The preparation of passivation solution water and washing water also have strict water quality requirements for chloride ions, so as to ensure that the passivation products do not touch chloride ions, so as to avoid future troubles.
The passive film of stainless steel conveying chain belongs to the metastable layout which is restrained in thermodynamics. Its shielding effectiveness is related to the situation medium. During the utilization, it is necessary to wash at the current period, and remove the harmless substances from its appearance for a long time.
Especially in the case of chloride ion, avoid the appearance of the permanent emulsion of chloride ion and the use of the diluent such as stainless steel in the water for food appliances. After each contact with food, clean it to avoid the action of chloride ion and damage to the passivation film. For example, for the containers and equipment of dairy products, the chlorine ion contained in dairy products has a crushing effect on the passivation film. For example, for the dairy products of permanent gorgeous clothes, it will lead to corrosion and perforation of the capacity and equipment, so it is necessary to wash them on demand to restore the passivation film. For stainless steel alloy, the lower the appearance roughness, the smoother the appearance, the more difficult the foreign matters are, and the lower the corrosion probability of each part. As a result, stainless steel should be roughly finished in appearance.
In addition, the surface cleanliness of stainless steel is also very tight. The final washing after passivation should be carried out carefully. As residual acid promotes the cathode response, the film is broken, thus activating stainless steel and severely reducing the corrosion resistance