Reasons for carbon steel pipe rusting:
Carbon steel pipe is a kind of steel with high carbon content. Because its main component contains iron element, it is prone to oxidation reaction in humid environment, forming iron oxide, that is, rusting. Carbon steel is not a completely corrosion-resistant material, but because its surface has not been specially treated, it is susceptible to environmental corrosion, which aggravates the occurrence of rust.
Reasons for the discoloration of carbon steel pipe:
In addition to rust, carbon steel pipes will also change color and fade due to friction, scratches, poor durability and other reasons on the surface. Among them, the color change may be caused by the influence of heat treatment, precipitation hardening, surface treatment and other processing processes on the steel surface. (for example, the color becomes darker); and the fading is because the covering on the steel surface is peeled off or removed, resulting in irregular colors (the exposed steel is directly exposed to the air and begins to rust).
The reasons for the rusting of carbon steel pipes are as follows:
1. Medium that causes product corrosion
Moist air, hand sweat or dirt from product contact, water, acid, alkali, salt and chemical gases remaining on the metal surface may cause metal corrosion.
2. Corrosion resistance of metal
Metals that are prone to rust include pig iron, carbon steel, and structural alloy steel. Stainless steel, high-temperature alloys, and titanium alloys will rust in special environments.
3. Parts prone to rust
The parts that are easy to contact, adhere to and accumulate corrosive substances include grooves, seams, holes, edges, joint surfaces, hand contact surfaces, parking surfaces, etc., or rough surfaces, newly processed surfaces, sandblasting polished surfaces, etc., which are prone to corrosion. rust.
4. Corrosion-prone environment
Generally speaking, processing workshops such as pickling, heat treatment, electroplating, welding, painting, electrolysis, etc. are more prone to corrosion than mechanical processing workshops, because these workshops have a large amount of corrosive media.
Protection methods for carbon steel pipes:
The rust of carbon steel has a great influence on its appearance and service life, so rust prevention is very necessary. The following are several common carbon steel rust prevention methods:
1. Passivation
Rust is prevented by passivation. Passivation treatment is to form a protective oxide layer on the surface of carbon steel, which can prevent the steel from being further corroded by the environment.
2. Surface coating
Surface coatings such as
galvanizing and painting can effectively prevent carbon steel from rusting and form a protective film on the surface, which can resist corrosion from the external environment and improve the hardness and durability of the surface.
3. Cement coating
Cement coating is another method for carbon steel to prevent rust. Although cement will absorb water, it will directly form a protective layer on the surface of the steel pipe. Therefore, cement coating is also a method of rust prevention.
4. Anti-rust oil treatment
The anti-rust oil added with anti-rust agent can prevent the rust of carbon steel well, and can be used as anti-rust treatment for engineering machinery, automobile engine parts and so on. The use of high-density grease and preservatives can prevent oxygen from entering the surface of carbon steel, thereby reducing the occurrence of oxidation reactions.
5. Electronic rust removal technology
The application of electronic rust removal technology can completely remove the rusty substances generated on the surface of carbon steel without changing the physical properties of the steel, so as to achieve the purpose of rust prevention.
In conclusion:
Carbon steel is susceptible to rust due to corrosive factors such as oxygen and water vapor in the environment. In order to prolong the service life and beautiful appearance of carbon steel products, we need to take some effective anti-rust measures, such as steel pipe passivation, surface coating, cement coating, anti-rust oil treatment, electronic rust removal technology, etc. These measures can help us better protect carbon steel products and make them more durable.
