Difference Between HOT DIPPED GALVANIZED Pipe and Cold Galvanized Pipe


Galvanization is an intricate process that makes industrial products such as the HOT DIPPED GALVANIZED PIPE. Galvanization occurs in many different steps, and hot-dipped galvanization is one form of it. In simple words, various forms of metal are coated with zinc. The chemical reactions that occur during the coating process are not suitable for all areas. The galvanization factories are usually located many miles away from industrial areas.

Furthermore, the process is becoming increasingly technology dependent. The mass machinery used in the procedure requires minimal human intervention. The galvanization process takes up many hours; the final product is impeccable.

Galvanization dates back to early times. Rusting is a nuisance and incredibly frustrating when you have spent so much on manufacturing specific machinery. Metal is coated with zinc to prevent any premature rusting throughout the length of the product.

Many machines have become redundant just because of rusting. Rusting is natural and sometimes unavoidable. Machines are bound to deteriorate over time. Chemistry plays a role in understanding this concept.

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Zinc acts as a protective layer around the metal object; thus, galvanization is essential before items like pipes enter the market. Pipes carrying fluids such as water and waste need protective coating more than other forms.


Treating a HOT DIPPED GALVANIZED PIPE Industrially

Although zinc will protect the HOT DIPPED GALVANIZED PIPE from rusting, it is not a lifetime solution. The zinc coat definitely lasts longer than average paint; however, the coating only extends until forty to fifty years.

The rust will eventually start to settle. At that point, the pipe itself may become compromised; therefore, a replacement is a much more sensible solution rather than recoating. The zinc coating, if correctly done, is an ideal solution to stop all chances of corrosion. Hot-dipped galvanization is more popular than one might think.

Hence, an easy way to spot a galvanized object is by focusing on the outer hue. A muted grey color is the most prominent hint in identifying a galvanized object. Hot-dipped galvanization is much more cost-efficient and reliable than other forms of coating.

Zinc is not inexpensive, but the coating only involves a thin layer of zinc. The zinc coating is barely detectable after a few years. Investing in the galvanization process will save the buyer from any future loss.

Metal usually oxidizes quickly when exposed to the outer environment. Pipes usually carry material underground, but that does not mean that they will not rust.

In fact, a metal that comes in contact with water is more likely to oxidase since the oxidation process is incomplete without two essentials, water and oxygen. Although materials like austenitic stainless steel and aluminum are less prone to rusting, they are not economical.

The process of making a HOT DIPPED GALVANIZED PIPE

There are many methods of trialed and tested galvanization that suit different metals and objects. Hot dipped galvanizing is perfect for protecting pipes. As the name suggests, this process involves dipping the metal pipe into a hot zinc bath. This method is dangerous to carry out without proper instructions and machinery.

There is a risk of the zinc spilling or the chemical reaction to go wrong—the entire process bases on a chemical equation. The most popular galvanization methods include hot-dipped galvanization, pre-galvanizing, electro-galvanizing or cold galvanizing. You can coat a metal pipe with other things that do not necessarily involve zinc; however, safety remains questionable.

The first thing involved in making the HOT DIPPED GALVANIZED PIPE include thoroughly cleaning the existing metal surface to ensure that the bonding remains seamless. An unclean surface will not bond with the zinc; thus, the zinc coating will not last on the metal. The layering is only possible when the base metal has a clean surface, either mechanically or chemically. Once the cleaning process ends, the base metal gets fluxed to remove all chances of residue. The base metal should have the perfect chemical balance so that a strong bind forms.

The second part of the galvanization process is relatively easy. Hot-dipped galvanization is ideal for different shapes and much easier to perform compared to other forms of it.

During the second part, the metal base submerges in a zinc tub. The zinc solution is heated up to 500 degrees. The zinc itself is present inside a huge container. Metal pipe has a basic cylindrical shape; thus, the zinc reacts over the entire surface area.

Choosing hot-dipped galvanization method over cold galvanization

A cold galvanized pie has one similarity with a HOT DIPPED GALVANIZED PIPE, it coats the pipe with zin, but the similarity ends right there. The method of a cold galvanization process differs from the hot-dipped one because it is more intricate and costly.

\The result is comparatively uniform; however, the outer layer is thin compared to hot-dipped galvanization. The process involves many chemical reactions. Cold galvanization uses electrical current in an electrical solution to carry the zinc ions towards the pipe. This method is effective in its own way but does not work best on already manufactured products such as pipes.

The thinner coating and more challenging method rank the cold galvanization process below the hot-dipped one. Cold galvanizing does not penetrate the surface, and it is merely brushing zinc against the body. Pipes prone to get placed in areas with higher chances of oxidation require a more effective method such as hot-dipped galvanization.

Cold galvanization is still the right choice for thin metal sheets that do not have the same applications as a pipe. The electrical transmission is useful, but it does not satisfy the requirements of a larger product.

The application of a galvanized steel pipe

Steel pipes faced most of their demand to carry water for household and industrial use. The high corrosion levels increased the metal intake in these areas, thus making it a health hazard. People abandoned the use of steel pipes for water transmission; however, the galvanization process's introduction made it possible to use them again.

A galvanized steel pipe can offer many industrial applications such as the transmission of goal, gas and steam. The galvanization methods may differ, but the result will only protect the pipes from undesirable corrosion. The method used to galvanize pipes depends upon the budget and application of it.

Since hot dipped galvanization has been around for more than 180 years, it has developed many times over the years. The galvanization process does not require the same effort as it once did.

Advanced machinery has removed many steps from the process. The life cycle of the pipe includes cleaning, washing, plating and then drying. The process does not end when the pipe comes out of the zinc solution; it still has to undergo finishing.

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A hot-dipped galvanized pipe will last according to the use it gets put on. The lifetime for an industrial application is comparatively less than other applications. Rusting is no more an issue with the galvanization system.

Other coating materials such as paint do not give the same satisfaction as zinc. Strong acid conditions can speed up the rusting process; therefore, a lighter atmosphere is recommended for these pipes. Galvanized pipes are safe to touch after the process; the zinc does not harm the skin.

Rust treatment has evolved over the years; however, hot-dipped galvanization is still the most popular form. The method suits all forms of metal and gives a uniform finish to the metal surface. For this reason, many industries favor hot-dipped galvanization to protect expensive machinery and products.

For further information regarding the hot-dipped galvanization process, have a look at our website.