Sep. 30, 2020
Since the galvanized square pipe is galvanized on the square pipe, the application range of the galvanized square pipe has been greatly expanded compared to the square pipe. It is mainly used in curtain walls, construction, machinery manufacturing, steel construction projects, shipbuilding, solar power generation brackets, steel structure engineering, power engineering, power plants, agricultural and chemical machinery, glass curtain walls, automobile chassis, airports, etc.
Zinc plating refers to a surface treatment technology that coats a layer of zinc on the surface of the metal, alloy, or other materials for aesthetics and rust prevention. The main method used is hot-dip galvanizing.
Zinc is easily soluble in acid and alkali, so it is called amphoteric metal. Zinc hardly changes in dry air. In humid air, a dense basic zinc carbonate film will be formed on the surface of zinc. In an atmosphere containing sulfur dioxide, hydrogen sulfide, and marine atmospheres, zinc has poor corrosion resistance, especially in an atmosphere containing organic acids at high temperature and humidity, the zinc coating is easily corroded. The standard electrode potential of zinc is -0.76V. For the steel substrate, the zinc coating is an anodic coating. It is mainly used to prevent the corrosion of steel. The quality of its protective performance is closely related to the thickness of the coating. After the zinc coating is passivated, dyed, or coated with a light protectant, its protective and decorative properties can be significantly improved.
Principle of galvanizing:
In the plating tank containing the galvanizing solution, the cleaned and specially pretreated parts to be plated are used as the cathode, and the anode is made of plated metal, and the two poles are respectively connected with the positive and negative electrodes of the DC power supply. The zinc plating solution is composed of an aqueous solution containing metal-plated compounds, conductive salts, buffers, pH adjusters, additives, and the like. After being energized, the metal ions in the zinc plating bath move to the cathode under the action of the potential difference to form a plating layer. The anode metal forms metal ions into the zinc plating solution to maintain the concentration of metal ions to be plated. In some cases, such as chromium plating, an insoluble anode made of lead, and the lead-antimony alloy is used, which only serves to transfer electrons and conduct current. The concentration of chromium ions in the electrolyte needs to be maintained by regularly adding chromium compounds to the plating solution. When galvanizing, the quality of the anode material, the composition of the galvanizing solution, temperature, current density, energization time, stirring intensity, precipitated impurities, power waveform, etc. will affect the quality of the coating and need to be controlled in a timely manner.
The above information is provided by the galvanized steel pipe manufacturer.
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