Hot-dip galvanized steel pipe and electro-galvanized (cold galvanized) steel pipe are two common anti-corrosion steel pipes. They differ significantly in process, coating thickness, cost and applicable scenarios. Understanding these differences can help in making the right choice.
Process Differences
Hot-dip galvanizing: the welded steel pipe is immersed in molten zinc at about 450°C, forming a zinc layer and zinc-iron alloy layer on the inner and outer walls. The coating is thick and firmly bonded.
Electro-galvanizing: zinc ions are deposited on the surface of the steel pipe by electrolysis, with a thin and uniform coating but lower corrosion resistance.
Performance Comparison
Coating thickness: hot-dip galvanizing is much thicker than electro-galvanizing, with stronger rust resistance
Cost: electro-galvanizing is cheaper but has a shorter service life
Applicable scenarios: hot-dip galvanizing is preferred for outdoor humid environments and fluid transportation; electro-galvanizing is suitable for indoor decorative parts or low-corrosion environments
Selection Suggestions
For long-term outdoor use or fluid transportation projects, hot-dip galvanized steel pipe is recommended; for parts with high surface requirements but low corrosion, electro-galvanized pipe can be selected.