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At Amazing Gates we use steel for the construction of our driveway gates, garden gates, and fence. We chose steel for its durability and strength. We then give the gate a Hot Dipped Galvanized (HDG) undercoat. The HDG process utilize the properties of Zinc to provide protection to the steel from rust and corrosion.

Why HDG?
During the Hot Dip Galvanizing, the gate or fence undergoes a 12 step process cleaning and preparing the steel, dipping the frame in various chemical baths, painting, and curing. One of the steps is to dip the gate in a Molten Zinc Bath. (In order to fully protect the steel both inside and out, any gate that is called "corrosion resistant" should be dipped, not painted.)

Hot Dipped Galvanized Process diagram
Hot Dip Galvanizing Process

The HDG undercoat provides excellent corrosion protection to the steel substrate, which is especially important in coastal or other wet environments. Our Hot Dipped Galvanized finish has been tested by immersion in saltwater for 1500 hours and another 1500 hours of salt air fog with no sign of base steel corrosion.

We provide a Lifetime Warranty on the steel substrate of our HDG gates.

Read below for detailed information on the Hot Dipped Galvanizing process.

Hot Dipped Galvanizing Process
provided by the American Galvanizer's Association

The fundamental steps in the galvanizing process are:

Soil and grease removal - A hot alkaline solution removes dirt, oil, grease, shop oil, and soluble markings.

Pickling - Dilute solutions of either hydrochloric or sulfuric acid remove surface rust and mill scale to provide a chemically clean metallic surface.

Fluxing - Steel is immersed in liquid flux (usually a zinc ammonium chloride solution) to remove oxides and to prevent oxidation prior to dipping into the molten zinc bath. 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.

Galvanizing - The article is immersed in a bath of molten zinc at between 815-850 F (435-455 C). 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.

Finishing - After the steel is withdrawn from the galvanizing bath, excess zinc is removed by draining, vibrating or - for small items - centrifuging.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

Inspection - Coating-thickness and surface-condition inspections complete the process. The galvanizing process has existed for more than 250 years and has been a mainstay of North American industry since the 1890s. Galvanizing is used throughout various markets to provide steel with unmatched protection from the ravages of corrosion. A wide range of steel products from nails to highway guardrail to the Brooklyn Bridge's suspension wires to NASA's launch pad sound suppression system benefit from galvanizing's superior corrosion prevention properties.

Galvanizing's primary component is zinc. This vital substance is silvery blue-gray in color and makes up an estimated 0.004% of the earths crust and ranks 25th in order of abundance. It is essential for the growth and development of almost all life: Between 1.4 and 2.3 grams of zinc are found in the average adult, and the World Health Organization has recommended a daily intake of 15 milligrams. Numerous consumer products including cold remedies, sunscreens, diaper creams, and nutritional supplements contain beneficial amounts of zinc, primarily in the form of zinc oxide.

Even though galvanized steel is blue-gray, it also is green. The zinc and galvanizing industries work to promote sustainable development by enhancing zinc's contribution to society and ensuring that its production and use are in harmony with the natural environment and the needs of society, now and in the future.

Zinc, as it is used in galvanizing, is a healthy metal, completely recyclable. The energy used to melt zinc is inversely related to the amount of zinc recycled. Galvanizing delivers incredible value in terms of protecting our infrastructure. Less steel is consumed and fewer raw materials are needed because galvanizing makes bridges, roads, buildings, etc., last longer.