Galvanizing Flux : Wet or Dry Method

 


Galvanizing Flux : Wet or Dry Method 


The advantages and disadvantages of the dry and wet methods are still disputed, which is better? But the choice depends to a large extent on the quality of the products for  galvanizing.


The main advantages of the dry method

• Higher production capacity.

• Reducing the output Dross.

• Lower operating cost.

The main disadvantages of the dry method:

• Needs a bath (more space)

• Needs heating (energy consumption)

• Needs continuous treatment or shut down to adjust the concentration of the tank and iron content 

• These equipments need continuous and periodic maintenance.

 The main advantages of the wet method:

• Providing space and equipment (there is no bath or heating).

• A layer of Flux on the surface of the zinc kettle gives a better cleaning of the products surface  especially when there were errors in the previous stages.


• In general, it gives less thickness of zinc, especially if the product is pulled through the flux layer, as it is abrasive.

• Increases safety when the products are not dried as it reduces zinc volatilization.

• The amount of ash may be less.

Disadvantages of the wet method:

• The product may be contaminated by flux.

 Rust may occur on the surface of the product, especially if  flux  that  stuck in the cooling pan does not removed.

• Loss of a quantity of zinc when scraping the products of flexi.

The cost of maintaining a layer of Flex on the surface of the zinc basin is more compared to the dry method.

 More Dross output

Increases the appearance of white rust

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