We all know that wallboard nails (drywall nails) need to be phosphated, unlike other self-tapping screws. In order to standardize the operation of the screw phosphating process, to avoid the unqualified quality caused by operating errors.

1. Put the screws in the hydrochloric acid bucket, pickling and activating the surface of the screws;

2. Put the screws in a bucket of clean water and clean it by Barros;

3. Put the cleaned screws into the blackening tank for blackening treatment (the surface becomes black, and the color should not fade). The configuration of the blackening tank is: 5% black dyeing solution plus 3% hydrochloric acid 5% plus 90% room temperature clear water;

4. Put the screws in a bucket of clean water, and clean the screws;

5. Put the cleaned screws into the meter adjustment slot for meter adjustment treatment. Table adjustment configuration: Table adjustment 2% with room temperature water (PH>8);

6. Put the adjusted screws into the phosphating tank for phosphating treatment. Phosphating configuration: 9% phosphating solution plus 90% water, heating at 90°C for 5-10min, and the screw surface can be evenly phosphated;

7. Put the screws in a bucket of clean water and clean the screws;

8. Put the cleaned screws into a spin-drying bucket, and spin-dry the screws; the last step is to put the spin-dried screws into a bucket with anti-rust oil, soak them, soak them evenly, and then lift them out.