Restoration of the body is carried out immediately after the discovery of a defect. The body is most susceptible to corrosion. According to the degree of damage, corrosion can be divided into three groups: cosmetic, penetrating and structural.
Cosmetic corrosion appears on the outer surfaces in the form of pitting rust at the points of contact of the body with overhead parts - decorative overlays, lights, as well as on the edges of the door flanges, hood, trunk lid. This type of corrosion appears primarily where the paintwork is damaged. Deteriorating the appearance of the car, cosmetic corrosion, if left untreated, progresses and turns into penetrating corrosion.
Penetrating corrosion affects the most difficult to visually control places where moisture and dirt accumulate. It is discovered when the damage it has caused is difficult to repair. The inner surfaces of box-sections, the surfaces of the front and rear fenders, the thresholds and floor crossbars, the floor itself from the passenger compartment, and the internal cavities of the doors are most susceptible to its influence.
Structural (through) corrosion affects the attachment points to the body of the power unit, chassis, elements that form the supporting frame of the body. Particularly susceptible to structural corrosion are elements that experience abrasive and corrosive effects - the bottom, sills, wheel arches, front and rear fenders. The loss of mechanical strength of these elements leads to failure of the entire car body.