Dacromet coating with 20- 60s spray coating / 60-90s dip Spin
coating Specific gravity 1.30±0.05
1. Product Information
Trade Name: Zincover
2. Composition/information on ingredients
JH-9392 is made up of three packs: A,B and C;
Pack A: It is silver gray slurry that mainly chemically combined
with super fine flake Zn, super fine flake Al and ethylene glycol.
The radius-thickness ratio of Zn plate is 60~100.
Pack B: It is the solvent of the coating colored in orange-red and
in water solution, which contain the Cr6+.
Pack C: It is the tackifier of the coating which mainly made up of
cellulose white or yellowish powder.
3. Coating Process
3.1 Mix Ratio
Pack A:16.0 kg
Pack B:24.0 kg (the quantity can be increased appropriately if
Pack C:0-50 g (according to different viscosity demand )
Before Mixture, Keep weighted A&B into the water bath at 25±2℃
, then stir A to make metal slurry disperse uniformly by frequency
mixer ,after A is fully evenly dispersed, reduce the agitating
speed to 60r/min, and add B.
|Add B to the stirring A slowly. At the moment ,the barrel
temperature will go up,when it reaches 35℃, startup refrigerating
device to keep the barrel temperature constant at 35℃.|
Stir the mixture about 1~2 hours fast after B added, then add C. C
should be powdered if lump exist.(The barrel temperature should not
be lower than 30℃, otherwise C will not be dissolved sufficiently
.)Then stir 12 hours continuously.
The coating should be filtrated by 80~100 mesh stainless steel
screen before pouring into dip barrel.
Temperature control device should be equipped with dip barrel to
keep the temperature of coating at 22±2℃.(If temp. is too high, the
paint is liable to deteriorate, and viscosity will be effected.)
The coating should be stirred circularly to keep evenly dispersed.
Test density,PH,Temperature,Viscosity and Cr6+ content of coating every 8 hours if operate continuously.
4. Technical data
|4||Viscosity||20~60s(Spray Coating) ; 60~90S(Dip-Spin Coating) . 20℃ Zahn 2# cup|
5. Mix Diagram
Caution: Temperature should be controlled in above operation.
6. Coating Process
The workpiece should be degreased if there is oil on the surface.
There are three processing methods:
2.Neutral water-base degreasing agent
3.Organic solvent such as methylene chloride.
The workpiece can not be coated if there is rust or burr on the
surface.The best processing method is shot blasting. The corrosion
resistance of coating will be effected if acid cleaning adopted.
The workpiece afer degreasing and shot blasting should be coated
through Dip-Spin coating or Spraying Coating.
The workpiece after coated should be Pre-heated as soon as possible
at 80~150℃ for 8~15 mins to evaporate. ( according to heat
absorption of workpiece.)
The workpiece after pre-heating should be cured at 300-340℃ for
20-40 mins. ( according to heat absorption of workpiece.)
Other chemicals such as any kinds of acid, alkali salt can not be
mixed into coating, for these can activate Zn & Al plate to
aging the coating.
Avoid irradiation of sunshine and ultraviolet ray for long time
when operating, otherwise it will accelerate aging or
polymerization of the coating .
It is very important to control the temperature of coating. If the
temperature of coating changes when operating, it will effect the
viscosity, then effec the coating quatity on workpiece. So the
relations among temperature,viscosity and spinning process shoud be
controlled well when coating.
The viscosity will be different if coating method is different.
Choose low data if spray coating,and choose high data if dip spin
|Pack A:||16kg/ Metal Barrel||Pack B:||24KG Plastic Barrel||Pack C:||5.0kg metal barrel|
9. Quality guarantee period
Before compound 6 months at 20℃
After compound 40 days at 20℃ ( It can be recycled if adding fresh
coating continuously. )
It should be stored under 20℃ if not in use.