Why does stainless steel manhole cover rust

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Stainless steel manhole cover is a kind of manhole cover that is very popular at present. It is not only easy to install, but also can play a role in decorating urban roads. It is strong and durable and has been widely used in many fields. But sometimes there will be rust, which will affect its use. So why does the stainless steel manhole cover rust and how to deal with it?

Why does the stainless steel manhole cover rust?

  1. In the process of processing stainless steel manhole covers, due to the contamination of iron and copper tools, the hydrogen protection during welding is not good, and oxidation occurs, causing the manhole cover to rust, so protect the hydrogen when welding.

  2. The manhole cover is made of materials that do not contain titanium and niobium, which has a tendency of intergranular corrosion. Adding titanium and niobium, together with stabilization treatment, can reduce intergranular corrosion.

  3. There are chloride ions in the use environment of the manhole cover, such as salt, sweat, sea water, sea breeze, soil, etc. In the presence of chloride ions, the manhole cover corrodes very quickly, even exceeding that of ordinary low carbon steel. Therefore, it has requirements for the use environment, and it needs to be wiped frequently to remove dust and keep it clean and dry.

  4. Some equipment for the production of stainless steel manhole covers does not take into account the needs of the process. Chemical substances containing acid and sulfur will often appear in the process of making stainless steel manhole covers.

  5. Excessive damage to the surface of the anti-oxidation layer of the stainless steel when it leaves the factory during the processing, causing it to form oxidation, causing pollution to the stainless steel and causing rust.

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How to prevent stainless steel manhole covers from rusting?

  1, spray rust removal

   When removing rust, be sure to remove all the rust, and remove all the oxides on the surface of the cast iron manhole cover. When the air pressure is 4-0.6Mpa. The power of the air separated from oil and water is very large.

   The friction between the air and the manhole cover is sufficient. Instant cleaning. The advantages of this cleaning are that it does not require a fixed location, is high in efficiency, has great flexibility in spraying points, and has no dead ends. Facilitate the adhesion of paint afterwards. Prevent rusting again.

  2, projectile rust removal

   under the centrifugal action of high-speed rotation. The abrasive can wake up and clean the manhole cover with a larger friction area. The advantages of this method are high efficiency, good rust removal quality, and a slight reduction in the high power of workers. The important thing is that the air pollution is relatively low. Therefore, generally large manufacturers use this method to remove rust.

  3, regular maintenance

   In the fluid control system, if you want to realize the control of various fluid media, it is naturally indispensable to control the composite manhole cover, which is used in air, corrosive media, oil, liquid metal, and radioactive media. In order to avoid rusty damage to the composite manhole cover, its regular maintenance is indispensable.

 The above is to introduce why the stainless steel manhole cover rusts and how to deal with it. I must have a certain understanding after reading it. If you need it, you can contact us.

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