How to process galvanized steel pipe

　　Galvanized steel pipe is widely used in construction steel structure, car production, mechanical production, bridge construction, container keel, ship production and other fields because of its excellent corrosion resistance, deep processing formability, painting and weldability, as well as good surface quality and inductive mechanical function.

　　The processing of galvanized steel pipe is to accumulate a layer of metal or alloy on the surface of the product through the electrolytic process of metal ions based on the principle of electrolysis, so as to change the physical and chemical functions of the product surface, eventually making the galvanized plate have wear resistance, decoration and impact resistance.

　　The electroplating process of galvanized steel pipe mainly includes pretreatment, electroplating and post-treatment. The quality of the coating depends on the electroplating process of the material, and the electroplating process is affected by many factors. The six factors are summarized as follows:

　　1. Sodium hydroxide: sodium hydroxide has two layers of influence on the response. When its content is too high, it is easy to be burnt in the process of high temperature operation; when its content is too low, the solution will be poor in laxity, which will reduce the quality of zinc layer.

　　2. Iron content: when the iron content is too high, there will be more iron in the coating, which will lead to the lack of brightness of the passivation film of the product; and if the iron content is too low, it will lead to the low iron content in the zinc coating, which will reduce the corrosion resistance of the car board, and will lead to the olive color on the car board surface.

　　3. Temperature: too high temperature in the electroplating process will cause solution laxity to decrease, iron content in the coating will increase, and the passivation will be uneven; however, when the reaction temperature is too low, the high current density area will be slightly burnt, and the coating brittleness is large and the stacking speed is slow.

　　Cathode moving speed: it is necessary to ensure that the cathode is in the moving state in the electroplating process. If the moving speed is too fast, the coating in the high current density area will be rough in the electroplating process. If the moving speed is too slow, air flow may occur, resulting in uneven coating of materials