1 Scope
This procedure is used to determine the resistanceto coating adhesion loss of coated surfaces ofaluminum, plastic, steel, and other substrates when subjected to a wet steam blast similar to thatproduced by vehicle wash equipment.
Note: Nothing in this standard supersedesapplicable laws and regulations.
Note: In the event of conflict between the English
ａnd domestic language, the English language shall take precedence.
Purpose. To determine the resistance to coating adhesion loss of coated surfaces of aluminum, plastic, steel, and other substrates when subjected to a wet steam blast similar to that produced by vehicle wash equipment.
Foreword. Not applicable.
Applicability. Painted exterior components of vehicle.
2 References
Note: Only the latest approved standards are applicable unless otherwise specified.
External Standards/ 2808
GM Standards/Specifications.
3 Resources
Facilities. Not applicable.
Equipment.
3. Test Equipment and Material.
. Scribe Tool. A straight-shank tungsten carbide tip, lathe cutting tool or carbide-tipped pencil type tool with tip angle of 60 ± 15 degrees or equivalent.
. Razor blade.
. Water Bath. Water bath at 38 ± 2°C temperature with 5 ppm maximum dissolved solids as measured utilizing a suitable dissolved solids meter.

3..4 Freezer capable of maintaining -29 ± 3°C temperature.
3..5 Steam generator.
Note: Model 100 (ａnd the earlier Model 60) steam generator (from Atomic Steam Co 10727 Fendell, Detroit MI 48238) has been found to be satisfactory. Milwaukee 7 cm ( 1 / 2 in) globe valve 1151 to 1161, 150 Steam Working Pressure,
300 Water-Oil-Gas, is adequate for use in standardization of generator.
3..5.1 Input Flow of Water. L/minute with a deviation less than 5% (3..5.).
3..5. Model 100 Steam Generator. The pumping pressure is directly related to the input flow rate. The pressure needed for the required flow can be determined by measuring the pump pressure and discharge flow rate with the burner off. When the burner is turned on, the required flow rate is obtained by readjusting to the required
pump pressure.
3..5.2 Nozzle Diameter. mm ID within 2% and at least 100 mm long.
3..5.3 Discharge Dynamic Head. kPa within ± 5% measured 25 mm from the nozzle using a 47 mm ID tube. A nondiverging discharge is required for this test (3..5. and 3..5. and Figure 1).
3..5. This is done by placing the tube midstream 25 mm from the nozzle. The tube size must not be varied because the densities and velocities are not uniform throughout the cross section of the discharge stream.
3..5. Adjusting the discharge dynamic head may be required. This must be done in such a way that the input flow rate as specified in .7.1 is maintained. This is done by adjusting the amount of heat transferred to the water. Increasing the heat will cause the input flow rate to change. It must be readjusted. This operation will result in an
increased dynamic pressure. To decrease it, decrease the heat and then adjust the flow (pressure).
3..6 Face Mask. Full face cover safety mask is requi