ã€China Aluminum Industry Network】 The main reasons are as follows:
The oxide film is in contact with oil or alkaline substances. After the anodization of the workpiece, contact with oil or alkaline substances must be prevented prior to dyeing to prevent the oxide film from being isolated from or damaged by the stain during the dyeing process. It was found that the oil stains on the hands of workers in the factory during the operation of the factory contaminated the workpiece, and that the parts with the oil stain were not stained.
The position of the fixture or the angle of suspension of the workpiece during the anodization is not appropriate. The position of the fixture and the angle of suspension of the anodized workpiece have a great influence on the quality of the oxide film, and in particular, it is not rare to generate a trap gas. To avoid this problem, In addition to the need for special attention in the clamping and hanging process, the workpiece should also be shaken many times during the anodization and dyeing process, so that the gas generated in the concave part of the workpiece can be eliminated in a timely manner.
During the process of dyeing, the "Yin and Yang planes" formed by the mutual adhesion of the workpieces due to the mutual adhesion of the dyes are mostly present on the flat surface. The workpieces that have appeared in this condition should be picked out before drying and faded in the chromic acid or nitric acid solution. Re-stain.
To prevent parts from sticking together during dyeing, the following methods can be used:
1 When the workpiece is dyed, do not remove it from the fixture, dye it with a jig, and shake it up and down several times during the dyeing process to prevent the fixture from coming into contact with an excessive white spot mark due to the top gas.
2 Remove from the fixture and put it in the plastic basket. Dyeing in the plastic basket after shaking it several times under the liquid surface can also obtain a uniform appearance quality. It should be noted that it can only be gently shaken in the dyeing solution, otherwise The workpiece will be scratched and a white mark will appear.
Steam Trap,Thermodynamic Steam Trap,Steam Trap Types,Thermostatic Steam Trap
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