First of all, the process difference:

Cold galvanizing, also known as electro-galvanizing, is to use electrolytic equipment to deoil and pickle the workpiece into a solution of zinc salt, connect the negative electrode of the electrolytic equipment, and place a zinc plate on the opposite side of the workpiece to connect to the electrolytic equipment. Positive pole, turn on the power supply, and use the current to move from the positive pole to the negative pole, a layer of zinc will be deposited on the workpiece;

Hot-dip galvanizing is to remove the oil, pickling, dipping, and drying the workpiece, and then immerse it in the molten zinc solution for a certain period of time, and then put it out.

The difference in appearance:

The appearance of electro-galvanizing is relatively smooth and bright, and the electroplating layer using the color passivation process is also mainly yellow-green in color, showing colorful. The electroplating layer using the white passivation process is bluish white or white and green, and the coating layer of the white passivation process is slightly colorful at a certain angle to the sunlight. In the corners and edges of complex workpieces, it is easy to produce "electric burning" and become gray, and the zinc layer in this part is thicker. It is easy to form a current dead angle in the inner corner, resulting in an undercurrent dark area, and the zinc layer in this area is relatively thin. The workpiece as a whole has no zinc nodules, agglomeration and other phenomena.

       The appearance of hot-dip galvanizing is slightly rougher than that of electro-galvanizing, and it is silver-white. The appearance is prone to process water lines and a little drip, especially at one end of the workpiece. However, the zinc layer of hot-dip galvanizing is dozens of times thicker than that of electro-galvanizing, and the corrosion resistance is dozens of times that of electro-galvanizing.