Views:3 Author:Site Editor Publish Time: 2020-08-06 Origin:Site
The gray color blocks of different sizes on the surface of the galvanized seamless pipe are galvanized color difference, which is a problem in the galvanizing industry at present, which is mainly related to the trace elements contained in the steel pipe itself and the components in the zinc bath. The stain does not affect the anti-corrosion performance of the steel pipe, only the difference in aesthetics.
The surface of each galvanized seamless steel pipe has a gradually obvious protruding trace from thin to thick. The trace is all zinc. After the galvanized seamless pipe is taken out of the zinc pot, the zinc liquid flows down the pipe wall. Cooled and solidified, each galvanized seamless pipe has a trace of polishing and spray paint near both ends. When hot-dip galvanizing, the pipe must be fixed on a special steel frame and immersed in the zinc solution together with the steel frame. After the galvanizing is finished, the fixed place will leave scars. For beauty, the area will be polished and sprayed with zinc.In the process of using galvanized seamless pipes, some customers will use grooved links to press grooves on the seamless pipes. Due to the thick zinc layer of the hot-dip galvanized seamless pipes, under the destructive external force, some It will cause cracking and peeling of the galvanized layer, which has nothing to do with the quality of the galvanized seamless pipe itself.
Some customers will report that there is a yellow liquid on the galvanized seamless pipe (this liquid is called passivation liquid), the passivation liquid can make the metal surface passivation solution. Generally used for the post-plating treatment of zinc plating, cadmium plating and other coatings. The purpose is to form a surface state that can prevent the normal reaction of the metal on the surface of the coating, improve its corrosion resistance, and increase the appearance of the product. Can effectively improve the corrosion resistance of steel pipes and prolong the service life of workpieces