This product is suitable for cold drawing pretreatment of steel pipes, billets, etc., to form a water-insoluble crystalline sulfate conversion film on the surface area, which is called phosphating. The phosphating film is shimmering and luminous, uniform and detailed. It is light gray, dark gray, light blue or iridescent depending on the length of the phosphating time. Because the phosphating film is fine crystals, the spray mold has strong adhesion. This product is Normal temperature phosphating solution, simple operation, less slag, stable bath, strong phosphating film, and strong anti-rust ability, increasing the adhesion of plastic powder.
2. Main technical parameters:
1. Appearance of concentrated liquid: colorless or light blue liquid
2. Free acidity: 60±0
3. PH value: 2-3
4. Specific gravity: 1.3±.1
5. Concentration: 1:10
6. Working temperature: normal temperature
7. Soaking time: 5-30 minutes
Three, process flow
Degreasing-washing-pickling activation (no rust without this process)-washing-phosphating-drying or blow drying
Fourth, use method and bath management
1. After using for a period of time, the bath liquid will be consumed to reduce the total acidity and increase the PH value. Therefore, the pH value should be checked before each phosphating and adjusted to about 2-.3 before continuing to use.
2. The specific adjustment method is as follows:
PH value is too high (generally when PH>3.5 start to adjust), add 25kg phosphating solution to each cubic tank liquid, the PH value will drop by 0.5 unit.
3. Pickling tank: using ceramic, plastic or stainless steel materials.
5. Detection method of free acid and total acidity:
1. Free acid: Take 10ml of working solution or concentrated acid and transfer it into a 250ml triangular beaker, add 50ml of distilled water droplets into 2 drops of 1‰ methyl orange indicator solution, the liquid is red. Use 0.1N NaOH to drop to orange as the end point. The number of milliliters of NaOH consumed is the number of free acid points. If you take 2ml of concentrated solution, you should multiply it by 5 to get the concentrated free acidity points.
2. Total acidity: Take 10ml working solution or 2ml concentrated solution into a 250ml triangular beaker, add 50ml distilled water droplets into 5 drops of 1% phenolphthalein indicator solution. Use 0.1N NaOH to drop to red as the end point. The number of milliliters of NaOH consumed is the number of free acid points. Similarly for 2ml concentrated solution, multiply by 5 to get concentrated free acidity points.
25Kg plastic bucket