Basic coating of ferrous metal sheet

Ferrous metal sheet is easy to be exposed to air or contaminated with harmful substances and other factors, gradually oxidative corrosion and lead to yellow rust spots, damage the original coating. Especially in the process of sheet metal processing after hammering, welding and other parts of the process, more likely to make the original coating protective layer was damaged, accelerated corrosion, even if spraying film, the film will soon fall off with the base coating. At this point, a thorough coating process must be done again.

Clean the surface of ferrous metal with wire brush or iron sand paper. Conditional use of the now widely used cleaning tool - nylon abrasive disc for metal surface thoroughly grinding and cleaning. When the car body is disintegrated and repaired (especially for the accident car), spraying solution specially used for rust removal, paint removal, oxidation slag and dirt removal before and after metal welding should be sprayed at the folding edge and lap of the sheet metal, or substituted with rust-proof primer with good rust-proof ability.

Foundation coating for sheet metal parts

If the repaired automobile body is not treated with anti-rust treatment, it will be oxidized and rusted due to various impurities and water vapor in the joint of sheet metal parts within one or two years, which will affect the strength of welding joints. Therefore, zinc flux should be sprayed in time.

Welding zinc flux (zinc-rich coating) is a new kind of material specially used to prevent oxidation and rust on the joint surface of sheet metal parts. It has good electrical conductivity, high temperature resistance, and electrochemical cathodic protection. It can form a rust-proof protective layer between the welding joints of sheet metal parts, improve the ability of the parts around the solder joints not to be rusted, protect the solder joints, and ensure that the strength of the repaired body is not inferior to the original body.

Foundation coating for plastic welding

Although the surface of welds, welds and repaired steel plates has been polished and cleaned, there are still innumerable micro-invasive and irregular small bumps, which can not be seen by the naked eye, including numerous oxides, impurities, water vapor and so on. Ordinary putty or antirust paint, although with anti-rust function, but it can only prevent the intrusion of external rust, play a temporary sealing effect. As long as it is affected by humidity and other harsh environments, defects will soon appear. If epoxy primer is used, it will play an effective protective role.

Epoxy primer is a good rust inhibitor which can be applied to the seams of the overlapping joints of the panel after welding, grinding, heating and quenching shrinkage. It is usually done in the repair edge of the feather edge of the paint film (that is, the groove of the film), after cleaning the surface and then coated with epoxy primer, can ensure that after a variety of treatment after a long period of time without rust, even if the original rust, will also prevent the expansion of the rust range.

Foundation painting at joints

Without special sheet metal sealing treatment and direct coating of metal sheet, in welding or overlapping joints outside the seam will be due to a variety of debris, such as oil, coolant, sewage erosion and vibration of uneven road surface deformation and cracking, the anti-rust sealing line of the interface was broken, the function lost. The application of special sheet metal sealant on the surface of boards is an indispensable process.

Sheet metal sealant is a non-corrosive polyurethane PU structural adhesive, can fill seams, cover, bond and seal, and sometimes can replace welding, do not damage the paint skin. It has strong bonding force, high strength after curing, strong and reliable, can enhance the strength of single component and thin shell body, and can maintain the anti-erosion function of welding or overlapping joints, especially inside and outside wheel arch, chassis, reserve compartment, cabin floor and engine room.