What is GB/T 3091 Q195/Q215/Q235/Q345, BS 1387,EN 39, EN 1139 S235JR/S275JR, ASTM A53 GR. A/B/C, JIS G3444 STK 400/STK 500 Galvanized Steel Pipe
Galvanized Steel Pipe is a metal pipe material with a steel base, coated with a layer of zinc through processes such as hot-dip galvanizing or electro-galvanizing. This metallurgical bonding between zinc and iron forms a dense protective layer, effectively isolating the steel pipe from direct contact with the external environment and significantly extending its service life.
From a production perspective, hot-dip galvanizing involves immersing rust-free steel pipes into molten zinc at around 600°C, ensuring even zinc coating with a thickness typically exceeding 50 microns. This process creates a tightly bonded zinc-iron alloy layer with excellent corrosion resistance, making it particularly suitable for humid or saline environments. Electro-galvanizing, on the other hand, deposits zinc onto the steel surface through electrolysis. While more cost-effective, its corrosion resistance is slightly inferior to hot-dip galvanizing, making it more suitable for dry indoor environments.
The corrosion resistance of galvanized steel pipes stems from zinc's sacrificial anode protection. When scratches or damage occur on the zinc layer, zinc oxidizes preferentially to iron, forming a stable zinc oxide protective film that prevents corrosion from spreading to the base metal. Tests show that under identical conditions, galvanized steel pipes can last 3–5 times longer than ordinary steel pipes, significantly reducing maintenance costs and replacement frequency-especially for outdoor pipeline systems exposed to long-term weathering.
In construction, galvanized steel pipes are widely used in fire sprinkler systems, water supply and drainage pipelines, and air conditioning condensate pipes due to their high-pressure resistance (up to 1.6 MPa), meeting hydraulic demands in high-rise buildings. The smooth zinc surface also reduces fluid resistance, lowering pumping energy consumption. Industrially, they are commonly used for transporting corrosive media, such as chemical wastewater and seawater desalination systems, where their chemical corrosion resistance far surpasses that of ordinary carbon steel pipes.
GB/T 3091 Q195/Q215/Q235/Q345, BS 1387,EN 39, EN 1139 S235JR/S275JR, ASTM A53 GR. A/B/C, JIS G3444 STK 400/STK 500 Specification
GNEE Galvanized Steel Pipe For sale
