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    U-bolt oxidation anti-corrosion treatment


    There are many anti-corrosion technologies for U-bolts. […]

    There are many anti-corrosion technologies for U-bolts. Electroplating and oxidation are commonly used for processing. Today we share with you the U-bolt oxidation anti-corrosion treatment technology, as well as the benefits of this technology.


    The bolt is oxidized by immersing the steel part in an alkaline solution containing an oxidizing agent such as potassium nitrate or sodium nitrate in a sodium hydroxide solution and maintaining the boiling point at about 140°C, or immersing the steel part in sodium nitrate and nitric acid. In the molten salt of potassium, after being taken out and quenched in water, a pleasing layer of black oxide, ie, iron oxide film, is obtained on the surface thereof. The composition of the molten salt is a mixture of ferrous oxide and iron oxide, which is an improvement of corrosion resistance of ferrous metals. A simple and economical method. The thickness of the chemical oxide film is extremely thin, generally 0.5 to 1.6 μm, and the corrosion resistance is limited. The film with a thickness of 2 μm has a dull appearance and is black or dark gray. The film has good adsorption properties, such as dipping. After anti-rust oil or paint, its resistance to salt spray corrosion can increase several times to tens of times.


    The bolts are generally of steel material, and the material is easily corroded. Therefore, it is necessary to remove the oil and pickle before the oxidation treatment to remove the surface rust. One oxidation treatment is performed in one bath, and two oxidation treatments are performed in two baths with different solution components. The oxidized parts must be thoroughly washed, then boiled in soapy water, dried and oiled.


    Fasteners are generally subjected to anti-corrosion treatment because they are made of metal materials, and metal materials are easily oxidized and corroded in certain environments. Therefore, appropriate methods must be used for anti-corrosion treatment.