Galvanizing is a corrosion protection process for steel. It’s used to protecting steel from rusting. The galvanization process entails immersing clean, oxide-free iron or steel into molten zinc in order to form a zinc coating that is metallurgically bonded to the steel’s surface.

Galvanized steel can be applied on wide range of products because of its low cost, ease of application and comparatively long maintenance-free service life. The coating normally lasts at least 20 to 40 years in industrial environments and 50 to 100 years in less aggressive atmospheres.

Methods of Galvanizing

There are some different processes method for galvanizing steel:

  • Hot-Dip Galvanizing
  • Pre-galvanizing
  • Electro-galvanizing

Hot-Dip Galvanizing

Hot-Dip Galvanizing(HDP) involves dipping the base steel into a pool of zinc. First, the base steel must be cleaned either mechanically, chemically, or both to assure a quality bond can be made between the base steel and the zinc coating. Once cleaned, the base metal is then fluxed to rid it of any residual oxides that might remain after the cleaning process. The base steel is then dipped into a liquid bath of heated zinc and a metallurgical bond is formed.

HDP is a economical galvanization method, It’s more economical than stainless steel, and considered superior in terms of life-cycle. Galvanized steel is widely used in applications where corrosion resistance is needed, such as building materials, electric equipments. Galvanized steel is suitable for high-temperature applications of up to 392 °F (200 °C). It can be welded, performed quickly and to complex shapes.

As a leading steel manufacturer in China, Hengze Steel can supply high quality Hot-Dip Galvnized Steel Coils.


This method is similar to hot-dip galvanizing but is performed at the steel mill, usually on materials that already have a specific shape. Pre-galvanizing involves rolling metal sheet through a similar cleaning process to that of the hot-dip galvanizing process. The metal is then passed through a pool of hot, liquid zinc and then recoiled.


Unlike the previous processes, electro-gralvanizing does not use a molten bath of zinc. Instead, this process utilizes an electrical current in an electrolyte solution to transfer zinc ions onto the base metal. This involves electrically reducing positively charged zinc ions to zinc metal which are then deposited on the positively charged material. Grain refiners can also be added which helps to ensure a smooth zinc coating on the steel. Similar to the pre-galvanizing process, electro-gralvanizing is typically applied continuously to a roll of sheet metal.

Hengze Galvanized Steel Specification

As a galvanized steel manufacturer, We can supply different specifications of hot galvanized steel coils/sheets.

Technical StandardASTM DIN GB JIS3302
GradeSGCC SGCD or Customer’s Requirement
TypeCommercial Quality/DQ
Type of CoatingHot Dipped Galvanized
Zinc Coating30-275g/m2
Surface TreatmentPassivation/skin pass/non-oiled/oiled
Surface StructureZero Spangle / Mini Spangle / Regular Spangle / Big Spangle
Coil Weight3-10metric ton per coil
PackageStandard export package or customized
HardnessHRB50-71 ( CQ Grade )
HRB45-55 ( DQ Grade )
Yield Strength140-300 (DQ Grade)
Tensile Strength270-500 (CQ Grade)
270-420 (DQ Grade)
Elongation Percentage22 (CQ Grade thickness less 0.7mm)
24 (DQ Grade thickness less 0.7mm)