How to do a good job in the aluminum coil into the coil before the preparation work

From the whole market situation, people's demand for high-end products is still increasing, quite resistant to which fake and shoddy products, and aluminum coils will become part of the products we need, it makes our products more beautiful, more advanced. Aluminum coil has been used in electronics, packaging, construction, machinery and other aspects of the pipe.

Before the aluminum coil is formed into a coil, it needs to do some pre-treatment sections to ensure that the surface of the aluminum coil is clean. Lest there are residual oil and grease and smoothing agent on its surface, which will have an effect on painting and application. Therefore, the aluminum coil should be pre-treated in the following aspects before forming.

First of all, you may use hot water to scrub the aluminum coil. Hot water scrubbing mainly if the substrate surface residues of degreasing agent scrubbing clean, to ensure that these residues can be dissolved in order to prevent these degreasing agent on the substrate to form a secondary pollution. The way to use more for the immersion and spray scrubbing way. The hardness of the water used should not be very high, otherwise, the minerals in the water will generate mineral spots on the surface of the substrate.

Secondly, hot alkali degreasing due to pre-coating line line speed, so the degreasing agent used is usually higher concentration, typical degreasing agent contains sodium hydroxide (NaOH), sodium carbonate (Na2Co3), water glass (Na2SiO3), phosphate and other components. Hot alkali degreasing process is usually divided into two steps to ensure that the aluminum coil substrate surface scrubbing clean, and more spray brushing way.

Again, it is passivated. Passivation treatment is through pressurized spraying, dipping or roller coating, etc. to make the passivation agent on the surface of the substrate to form a conversion film. Usually using pressurized spraying, passivation solution in the process of using the sludge often congested spray holes, thus affecting the effectiveness of spraying. Although the dip coating way to deal with this problem, but the passivation solution of a larger amount of hair. The above two ways in the essence of the manipulation of the need for water to clean the surplus passivation solution, there will be wastewater recovery and purification issues, roller coating is a good way of passivation construction, has a coating average, affordable, do not need to be drenched and other advantages. Aluminum plate usually choose chromate / oxide type treatment agent, this type of treatment agent contains chromate, chromic acid, phosphoric acid and contributing agent fluoride and molybdate. Phosphoric acid must be added to this type of treatment, otherwise it cannot be used to treat aluminum sheets for food and beverage applications.