It is well known that hot dip galvanizing has the effect of oxidation rust and corrosion on steel the poles, and powered spraying is also conducive to the durability and service life of the lamp poles.
But sometimes many national tenders require no powered spraying/coating,then we will use passivation treatment, the advantage of passivation treatment is that it has good corrosion resistance, can protect the street pole from oxidation corrosion for a long time, and can form a layer of beautiful color on the surface. But it looks mainly like after hot dip galvanizing, showing a silver state. This passivation process is mainly used in the Middle East, and some countries in Africa, Asia, South America and European.
The principle of passivation is: the process of forming a trivalent or hexavalent chromium layer with chromate solution and metal on its surface is called passivation, also known as chromatization. It is mostly used for the treatment of aluminum, magnesium and its alloys, and can also form a chromified layer for steel, but it is rarely used alone, often used with phosphating to close the pores of the phosphating layer, passivate the exposed steel in the phosphating layer, and inhibit the corrosion of the residual phosphating accelerator to further increase the protection ability. Passivation is generally used with potassium dichromate solution (2 to 4 grams/liter, sometimes also add 1 to 2 grams of phosphoric acid), soaked in 80-90 degrees Celsius for 2-3 minutes, water can be washed.
As our exporting experience to the word wide market:Kuwait,Jordan,Saudi Arabia more prefer passivation technology,then some Africa countries like Tanzania,Togo, etc,sometimes they prefer passivation technology for street light poles and solar street light poles.
More information,welcome to contact us at director@forever-lighting.com,thank you.
