Manufacturing Process of Hot Dip Galvanizing

The manufacturing process of hot dip galvanizing may vary slightly from plant to plant. The fundamental steps in the galvanizing process in nutshell can be described as under:

The steel articles are dipped into a hot alkaline solution or caustic soda solution to remove dirt, oil, grease, shop oil, and soluble markings for decreasing and caustic cleaning. The article is dipped in rinsing tank containing clean water for cleaning.



Second pickling is performed in second pickling tank which contains dilute solution of either hydrochloric or sulfuric acid 10-32% to remove surface rust and mill scale to provide a chemically clean metallic surface. The same article is again washed in rinsing tank containing clean water.The article is then preserved in pickling tank containing dilute solution of either hydrochloric or sulfuric acid 10-12% for first pickling.

Next step is Flux heating system where the steel is dipped in fluxing tank containing usually a zinc ammonium chloride solution to remove oxides and to prevent oxidation prior to dipping into the bath of molten zinc. In the dry galvanizing process, the item is separately dipped in a liquid flux bath, removed, allowed to dry, and then galvanized. In the wet galvanizing process, the flux floats atop the molten zinc and the item passes through the flux immediately prior to galvanizing.

The article is immersed in a bath of molten zinc of 435 to 455 degree Celsius. During galvanizing, the zinc metallurgically bonds to the steel, creating a series of highly abrasion-resistant zinc-iron alloy layers, commonly topped by a layer of impact-resistant pure zinc.

After the steel is withdrawn from the galvanizing bath, excess zinc is removed by draining, vibrating. The galvanized item is then air-cooled or quenched in liquid.

The most important part of hot dip galvanizing shows the value of experience is flux heating system. An experienced and noted hot dip galvanizing consultant in Gujarat Prashant Galvanizers supply Online Flux Filter System that eliminates production downtime. It eliminates or reduces iron content to a minimum in the flux solution which reduces Dross formation in zinc bath. Using Flux Heating system and Online Flux Filter system, zinc consumption is reduced anywhere from 1-2 kg per metric.

The material is due for dispatch after “Passivation” and inspection formalities. Coating-thickness and surface-condition inspections complete the process of hot dip galvanizing.

Hot-Dip Galvanizing In Gujarat

Galvanization is the process of applying a protective zinc coating to steel, aluminum and iron, in order to prevent rusting. The term Galvanization is derived from the name of Italian scientist Luigi Galvani. Although galvanization can be done with electrochemical and electro-deposition processes but the most common and popular method in present time is Hot Dip galvanizing, in which steel parts are submerged in a solution of molten zinc.

Process of coating of thin layer of zinc on iron, steel and aluminum at a temperature of about 860 °F (460 °C) by a bath of molten zinc is called Hot Dip Galvanizing. It is a form of galvanization. Oxygen (O2) in the atmosphere reacts with the pure zinc (Zn) to form zinc oxide (ZnO), which forms zinc carbonate (ZnCO3) by reacting with carbon dioxide (CO2) of the atmosphere. Generally it looks dull gray and in many circumstances it stops further corrosion, protects the galvanized material from the effects of outside elements. Rust resistance is the main cause of widely use of steel, and can be recognized by spangles on the surface (The size of crystallites in galvanized coatings is a visual feature, known as spangle).

Hot Dip Galvanizing is a factory controlled metallurgical combination of zinc and steel that provides corrosion resistance in a wide variety of environments. Hot Dip Galvanizing protects steel from corrosion in two ways. It provides cathodic protection and barrier protection.

Cathodic protection is commonly applied to a coated structure to provide corrosion control to areas where the coating may be damaged.  It may be applied to existing structures to prolong their life.

Barrier protection is commonly applied to a Hot Dip Galvanizing done surface to protect structure from germs in air or water, which prolongs its life and sustainability.

Prashant Galvanizers expertise of nearly 15 years in galvanizing contractor, manufacturer and supplier of India have an experienced and proficient technicians working team for manufacturing Hot Dip Galvanizing plants. They undertake any kind of critical job like tower line angle, channel and pipe of Shipyard Company, fabrication of tower-line, etc.

Most important and notable fact for Prashant Galvanizers is their un-imaginable capability of manufacturing of automatic/manual galvanizing plant system or 2-in-1 hot dip galvanizing plant system. They have earned a name and fame in a short time among the Galvanizers Consultant in India.