Galvanized Steel Pipe vs. Black Steel PipeGalvanized steel pipe features a protective zinc coating that helps prevent corrosion, rust, and the buildup of mineral deposits, thereby extending the pipe’s lifespan. Galvanized steel pipe is most commonly used in plumbing .Black steel pipe contains a dark-colored iron-oxide coating on its entire surface and is used for applications that do not require galvanization protection. Black steel pipe is used primarily for transporting water and gas in rural and urban areas and for delivering high-pressure steam and air. It is commonly used in fire sprinkler systems thanks to its high heat resistance. Black steel pipe is also popular for other water transfer applications, including potable water from wells, as well as in gas lines.