Hot Dipped Galvanizing Process

1- Loading Steel Rolls and De-coiling on Pay-off Reel machine .

2- Jointer Welder : Welding a new coil to the rest of previous coil for entering into the continuous production line .

3- Entry Accumulator : To accumulate and storing some lengths of coils for interrupting time .

4- Pre-treatment :

1-4- Washing : Plain water is used for primary cleaning and remove dust or soil .

2-4- Degreasing : A hot alkali solution and some detergent additives is often used to remove
organic contaminants like dirt, paint markings, grease, oil, and soluble
paint markings from the metal surface.

3-4- Rinse : A tank containing plain water is used to remove residues of the caustic dip.

4-4- Pickling : A bath of heated dilute sulfuric acid solution or ambient temperature
hydrochloric acid removes rust and mill scale from the products.

5-4- Rinse : A plain water tank is used to remove residues of the pickling process .

6-4- Flux dipping : Fluxing removes oxides and prevents further oxides from forming on the
surface of the metal prior to galvanizing and promotes bonding of the zinc
to the steel or iron surface. The method for applying the flux depends upon
whether the particular galvanizing plant uses the wet or dry galvanizing
process.

  In the dry galvanizing process, the steel or iron materials are dipped or
"pre-fluxed" in an aqueous solution of zinc ammonium chloride. The
material is then thoroughly dried prior to immersion in molten zinc. </