Is the basic coating process applied to body sheet metal parts? (two)

1. Basic coating of joints

Metal sheets that are directly coated without special sheet metal sealing treatment will be eroded and uneven by various sundries, such as oil, coolant, sewage, etc. The vibration of the road surface causes deformation and cracking, and the anti-rust sealing line of the interface is broken, and the function is lost. It is an indispensable process to apply special sheet metal sealant to the meeting and other parts of the sheet.

Sheet metal sealant is a non-corrosive polyurethane PU structural adhesive that can caulk, cover, bond and seal, and sometimes replace welding without damaging the paint. It has extremely strong adhesion, high strength after curing, strong and reliable, can enhance the strength of single-piece components and thin-shell body, and can maintain welding or lap joints, especially the inside and outside of wheel arches, chassis, trunk, and cockpit. Anti-corrosion function of the base plate and engine compartment.

2. Basic coating in the cavity of the box section member

During the overhaul of the car body, it will be found that the original sheet metal parts in the cavity of the box section member have been rusted and repaired due to accidents before, and the steel plate has become thinner and penetrated. infiltration and continuous expansion. These van-type cross-sectional members are often the main load-bearing members of the monolithic body, and they will have an important impact on the crashworthiness and durability of the car. Therefore, anti-rust treatment must be done for the box section or the cavity of the bag-shaped member.

Anti-rust protection wax inside the car body is a good assistant for cavity protection. It has excellent permeability and can easily penetrate into all corners and joints. Rotten wear to prevent rust inside the welding part of the body plate. In addition, when coating the inner surface of these plates, special spray bars and nozzles can also be used for coating. Ensure final repair quality.

3. Other functions of body base coating

1. Anti-vibration treatment at the junction of the skeleton and the skin

After the engine cover and luggage compartment cover are disassembled, body sealant must be filled between the skin and the inner lining before closing. This allows the folded skin to stick to the inner lining, otherwise the skin will loosen, there will be abnormal noises when opening or closing the hood or luggage compartment lid, and resonance sounds may also occur during driving.

2. Insulation, moisture-proof and noise-proof treatment of the underbody

On the upper surface of the body floor, the metal surface of the sheet metal components and the welding parts must be polished and sprayed with anti-rust primer. After drying, the sound insulation lining or sound insulation pad of the same type of the original body must be pasted to absorb the vibration and noise caused by the movement of the vehicle. generated noise.

For the lower surface of the body floor (the side outside the body), the exposed and repaired metal surface should be thoroughly polished and cleaned, the surrounding original paint that is about to fall off should be completely removed, and 1 to 2 layers of anti-rust primer should be sprayed. After drying, add MSP body sealant or similar products to the joint surface and the gap, and then spray the anti-rust and anti-collision primer. The underbody treated in this way can enhance the anti-corrosion performance and reduce the impact of stone hitting noise on the cabin.

With the continuous intensification of competition in the automobile market and the increasing updating of automobile manufacturing and repair technologies, the basic coating process has attracted great attention from automobile manufacturers and maintenance service personnel. A wide variety of coating materials with complete specifications and good functions will undoubtedly further promote the improvement of maintenance quality and prolong the service life of automobiles.