Black Malleable Iron Pipe Fittings and galvanized steel pipe fittings are the two most common types of pipe used to transport liquids and gases. Both black malleable iron fittings and galvanized pipe are made of steel; however, galvanized pipe has a zinc coating, while black pipe does not. As a result, galvanized pipe is more durable. For transportation, black malleable iron fittings are more susceptible to erosion than galvanized pipe, making it more suitable for transporting gases, while galvanized pipe is suitable for transporting water rather than gases.
Galvanized fittings are covered with a layer of zinc, which makes these fittings more resistant to corrosion and helps prevent the accumulation of mineral deposits that can clog pipes. Galvanized pipe is primarily used to supply water to homes and commercial buildings; it is also used as scaffold framing due to its rust protection.
Black Malleable Iron Pipe Fittings
Galvanized pipe fittings are used in a myriad of outdoor and industrial applications because of the material's ability to resist corrosion and salt. Galvanized pipe and fittings can be used in most applications, with the exception of underground pipelines. While they work best in cold water piping, they can also be used for hot water. The main advantage of using galvanized fittings is that they offer superior rust resistance compared to black and carbon steel fittings. Galvanized fittings should not be used for gas applications.
Black malleable cast iron fittings are used to make connections to carbon steel fittings. Carbon steel fittings are used in residential applications to transport natural gas and propane gas.
Carbon steel fittings are manufactured as Seamless Steel Pipe, which makes it a better type for natural gas transportation and fire sprinkler systems because it provides better protection against fire than galvanized pipe. Carbon steel fittings are also most often used in fire sprinkler systems because of their high heat resistance; black malleable iron fittings are also used in water supply piping because of their resistance to water damage. It is called black iron pipe because of its dark surface color, which is formed from iron oxide during the manufacturing process.
The main difference between Carbon Steel Pipe Fittings and galvanized pipe is its surface. Black steel pipe has no coating and no steam is used in the manufacturing process, so it is widely used to deliver gases such as propane and natural gas to residential and commercial buildings.
Galvanized pipe has a zinc surface, so over time, minerals can flake off and clog the pipe. This can lead to bursting. With this in mind, transporting natural gas in galvanized pipe is dangerous, so it is often used to carry water.
On the other hand, malleable cast iron steel pipe is not suitable for water transport. Iron steel pipes corrode easily in water, and minerals in the pipe can dissolve in the water and clog the pipe as well.