What’s The Difference Between Hot Galvanization And Cold Galvanization

Hot Galvanization And Cold Galvanization Pipe Supplier-GNEE

What's The Difference Between Hot Galvanization And Cold Galvanization?

 

Hot-dip galvanizing and cold-dip galvanizing are both zinc processing technologies. The way they are produced is very different, but they look similar. How to distinguish between hot dip galvanizing and cold galvanizing? Understanding more about the differences between hot-dip galvanizing and cold-dip galvanizing can prevent malfunction or damage to instruments, equipment, and more.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Manufacturing processes are different

Hot-dip galvanizing (hot-dip galvanizing) involves immersing the workpiece in a plating solution after processing. One of the advantages of hot-dip galvanizing is that the entire part is covered, including edges, welds, etc., thus providing full corrosion protection. It is a chemical reaction and the most popular method of galvanizing, widely used in the construction industry.

Cold galvanizing is also called electro-galvanizing. The workpiece after degreasing and pickling is placed into a zinc tank and connected to the electrolysis equipment. The current will move directionally from the positive electrode to the negative electrode to produce a zinc layer.

 

Differential zinc coating

Thicknesses as low as 45 µm can be achieved with this method. The thickness of the galvanized layer is affected by many factors, including the surface of the steel, the time the steel is immersed in the bath, the composition of the steel and the size and thickness of the steel being used.

Compared with cold galvanizing, hot dip galvanizing has a thicker coating, several times that of cold galvanizing, up to 30-80um. In addition, it has strong adhesion and high corrosion resistance, is not easy to fall off, and has a long service life. The surface of electro-galvanized steel is generally smooth, uniform, silver-gray, and free of zinc splatter.

 

different applications

Hot-dip galvanizing is suitable for workpieces of various sizes, especially for long-term rust prevention of relatively "rough" workpieces such as highway guardrails, power towers, large-size fasteners and other large outdoor steel workpieces. For example, early iron water pipes were hot dip plated.

Cold galvanizing is essentially a physical treatment. Since the coating is thin, generally within 5-30um, the corrosion resistance is relatively weak and the zinc layer is easy to fall off. Suitable for rust prevention indoors or small workpieces, such as the bottom of the chassis, panels or other small fasteners.

 

Price difference

Hot-dip galvanizing requires more zinc consumption, and it is said that the coating thickness is about 50-60% more expensive than electro-galvanizing. The cost of electro-galvanizing is indeed lower, but hot-dip galvanizing can achieve mass production and has a longer service life, which is cost-effective in the long run.