The commonly used derusting methods for ships include manual derusting, mechanical derusting and chemical derusting.

1、 Manual derusting

Tools for manual rust removal include hammer, shovel, scraper, wire brush, etc. Generally thick rust spots are loosened with a hammer and then removed with a shovel. The labor intensity is high, the efficiency of rust removal is low, generally 0.2~0.5m2/h, the environment is bad, it is difficult to remove scale and other dirt, the effect of rust removal is poor, it is difficult to achieve the specified cleanliness and roughness, and has gradually been replaced by mechanical methods and chemical methods. But in the process of ship repair, especially for the repair of local defects, this method is often used; Manual derusting is also often used for parts that are difficult to reach by mechanical derusting, such as narrow cabins, corners and edges on the opposite side of profile steel, and other difficult areas.

2、 Mechanical derusting

There are many tools and processes for mechanical rust removal, including the following four types:

1. Small pneumatic or electric derusting. It is mainly powered by electricity or compressed air, equipped with appropriate derusting devices for reciprocating or rotary motion to meet the derusting requirements of various occasions. For example, angle grinder, wire brush, pneumatic needle beam rust remover, pneumatic hammer, tooth type rotary rust remover, etc. are semi mechanized equipment. The tools are light and flexible. They can remove rust, old coatings, etc. thoroughly. They can roughen the coating. The efficiency is greatly improved compared with manual rust removal, up to 1~2m2/h, but can not remove oxide skin. The surface roughness is small, High quality surface treatment quality cannot be achieved, and the work efficiency is lower than that of spray treatment. It can be used in any part, especially in ship repair.

2. Shot (sand) blasting for rust removal. It is mainly composed of particle jet erosion to achieve surface cleanness and proper roughness. The equipment includes open shot blasting (sand) rust remover, closed shot blasting (sand chamber), and vacuum shot blasting (sand) machine. The open shot blasting (sand blasting) machine is widely used, which can completely remove all impurities on the metal surface, such as oxide skin, rust and old paint film. The rust removal efficiency is 4~5m2/h higher, the mechanical degree is high, and the rust removal quality is good. However, it is troublesome to clean the site because the abrasive cannot be recycled generally, which has an impact on other operations. Therefore, the environmental pollution is relatively serious, and its use has been gradually restricted recently.

3. High pressure water abrasive derusting. The impact effect of high-pressure water jet (plus grinding effect of abrasive) and water prying effect are used to destroy the corrosion and adhesion of coating to steel plate. It is characterized by no dust pollution, no damage to the steel plate, greatly improving the efficiency of rust removal, up to 15m2/h or more, and good quality of rust removal. However, the steel plate after derusting is easy to rust back, so special wet derusting paint must be applied, which has a great impact on the coating of general performance paint.

4. Shot blasting for rust removal. Shot blasting derusting is to use high-speed rotating impeller to throw abrasive to steel surface to achieve the purpose of derusting. It is an advanced mechanical treatment method for derusting hull steel. It not only has high production efficiency, but also has low cost and high degree of automation. It can realize assembly line operation with less environmental pollution, but only operates indoors.

3、 Chemical derusting

It is mainly a rust removal method that uses the chemical reaction between acid and metal oxide to remove the rust products on the metal surface, that is, the commonly known pickling rust removal can only be operated in the workshop.

      Spray processing ， Guangzhou spray processing ， Huadu spray processing The first choice is Guangzhou Tuoshen Surface Treatment Co., Ltd., which is worthy of your trust. Welcome to inquire!