Service life of hot-dip galvanized seamless steel pipe in different environments

The hot-dip galvanizing process is a relatively stable and reliable steel surface treatment solution to resist environmental corrosion. There are many factors that affect the hot-dip galvanizing, such as: the composition of the steel substrate, the surface condition (such as roughness), the internal stress of the substrate, and the geometry The thickness of the base material has a greater influence on the thickness of the hot-dip galvanizing, and the thickness of the hot-dip galvanizing is generally greater for thicker steel pipes.Hot-dip galvanized seamless steel pipe is processed by pickling and rust removal, zinc bath galvanizing, surface passivation and other processes to make the zinc bath firmly attached to the surface of the steel pipe. Galvanized seamless steel pipes last longer.

According to the requirements of the national standard, the local thickness of hot-dip galvanizing should not be less than 56μm, and the average thickness should not be less than 70μm.

If calculated according to the national standard, the average thickness is 70μm, and the zinc content is 70x7.2=504g/㎡. The usable life in four different environments is about:

Heavy Industry Park: 12. Years, the annual corrosion degree is 40.1;

Coastal area: 46 years, the annual corrosion rate is 10.8;

Outskirts: In 1993, the annual corrosion rate was 5.4;

Urban areas: 28 years, the annual corrosion rate is 17.5;