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Black steel pipe vs galvanized steel pipe

Galvanized pipe, also known as galvanized steel pipe, is divided into hot-dip galvanizing and electro-galvanizing. The hot-dip galvanizing layer is thick, with uniform plating, strong adhesion and long service life. The cost of electroplating is low, the surface is not very smooth, and its corrosion resistance is much worse than that of hot-dip galvanized pipes.

Black steel pipes are non-galvanized steel pipes. Black steel pipe, its name comes from the scaly, dark-colored iron oxide coating on its surface. Its used in applications that don’t require galvanized steel.

Black and galvanized steel pipes are both made of steel, but galvanized pipes have a zinc coating while black pipes do not. Therefore, galvanized pipes are more expensive and more durable.



The zinc of galvanized steel pipes serves as a sacrificial layer. It will rust before the steel beneath it, allowing the integrity of the pipe to remain intact for much longer time than regular pipes. Moreover, even if the zinc layer is scratched or damaged, it can still protect the steel beneath it.

The thicker your zinc coating, the longer the pipe lasts. The environment also plays a crucial role in determining the pipe’s life span. If the pipes are placed in highly corrosive conditions, they often last from 50 to 100 years. Applications of black steel pipes and galvanized steel pipes Black steel pipes and galvanized steel pipes are the two most common types of pipes used for transporting liquid and gas.

Black steel pipes are more likely to erode than galvanized pipes and for this reason, they tend to be used for transporting gas while galvanized pipes for carrying water.

The layer of zinc covering galvanized pipes offers it higher ability of corrosion protection, but as time goes by it can cause the mineral to flake off and block the pipe, which might lead to a burst. Transporting gas by galvanized pipes is therefore dangerous. Instead, it is used for carrying water to supply home and commercial buildings or serves as scaffolding frames thanks to its rust prevention.

In contrast, black steel pipes are uncoated and made without steam. Therefore, it is widely used for transporting gas like propane and natural gas to residential and commercial building. Black steel pipes can also be used for fire sprinkler system since it can prevent fire better than galvanized pipes.

Comparing costs of black steel pipes and galvanized steel pipes In general, black steel pipes are cheaper than galvanized pipes. It is due to the zinc coating on the galvanized pipes and the manufacturing process. Galvanized fittings also cost more than the fittings used on black steel due to its demand for maintenance.

There are two primary methods to distinguish black steel pipes and galvanized pipes:

First, you can examine the color of the pipe. Black steel pipe is darker than galvanized pipe; it is flat black while galvanized pipe is silver and gray.

And second, galvanized pipes are usually used for water transportation whereas black steel pipe for gas deliver.

Know more about this product price, catalogue, mill test certificate,  please inquiry to: sales@nan-steel.com

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