8.4. Anticorrosive protection of a body
Hollow profiles of a body, the bottom, the lower parts of doors and racks, and also connections of details of a body, including the place of spot welding are most of all subject to corrosion.
Most quickly corrosion develops in the hidden cavities and the lower parts of a body at hit of moisture, dirt, salts, acids.
In this regard in use the car additional protection of internal surfaces and the hidden cavities of a body by drawing special anticorrosive structures, and in connections of details putting sealing mastics is required.
The applied materials for anticorrosive processing are specified in tab. 8.1.
Table 8.1 Anticorrosive structures for processing of a body
Name of structure
|
Brand
|
Working viscosity, at 20 °C on VZ-4, sec.
|
Type of solvent, thinner
|
Drying mode
|
|
Temperature, X
|
Time, min.
|
||||
Autopreservative of thresholds
|
Movil Movil-2
|
15-40
|
White spirit, gasoline
|
20
|
22-30
|
Protective lubricant non-drying
|
NGM-ML
|
45
|
White spirit
|
20
|
15
|
Protective film covering
|
NG-216B
|
18-22
|
White spirit, gasoline
|
20
|
20
|
Mastic antinoise bituminous
|
BMP-1
|
High viscosity
|
Xylol, сольвент
|
100-110
|
30
|
Plastic compound polyvinyl chloride
|
D-11A plastisol
|
Too
|
-
|
130
|
130
|
Plastic compound
|
D-4A plastisol
|
Too
|
-
|
130
|
130
|
Mastic non-drying
|
51-G-7
|
Too
|
-
|
-
|
-
|
Movil, Movil-2 and Movil-ML autopreservatives are used for processing of the hidden cavities. It is recommended to process cavities every 1-1,5 year. Autopreservatives allow processing of the surfaces which are earlier covered nigroly or other oils, and also rusty surfaces.
The NGM-ML protective lubricant is applied to processing of the hidden cavities. This material processed the hidden cavities of new cars.
The protective film covering of NG-216B is used for a covering of parts of the car under a body.
Mastic antinoise bituminous BPM-1 is applied to protection against corrosion of the bottom of a body and to noise reduction. Thickness of a covering is 1,0–1,5 mm.
The plastisol of D-11A is used for protection of the bottom of a body against corrosion, against abrasive wear and for a noise isolation. Thickness of a covering is 1,0–1,2 mm. The plastisol of D-11A processed the bottoms of new cars.
The plastisol of D-4A is applied to sealing of welded seams.
Non-drying mastic 51-G-7 is used for sealing of joints of a body.
In internal cavities anticorrosive substance napylivatsya by way of air and airless dispersion.
At air dispersion compressed air with pressure of 0,5-0,8 MPas (5–8 kgfs/cm2), the gun-kraskoraspylitel with a tank, hoses and lengthening nozzles for the gun is required. The best quality of a covering is reached at airless dispersion under pressure of 4–12 MPas (40–120 kgfs/cm2) which allows to raspylivat materials of considerable viscosity.