The difference between hot-dip galvanized steel pipe and cold-galvanized steel pipe

The difference between hot-dip galvanized steel pipe and cold-galvanized steel pipe, hot-dip galvanized steel pipe and cold-galvanized steel pipe are called galvanized steel pipe, galvanized steel pipe is divided into two kinds, one is hot-dip galvanized steel pipe, one is Cold-galvanized steel pipe, cold-galvanized steel pipe is electro-galvanized steel pipe, the content of galvanizing is very small, only about 10 grams to 20 grams per square meter, its corrosion resistance is very poor compared with hot-dip galvanized steel pipe, hot-dip galvanized 4×4 square steel tubing The corrosion resistance is dozens of times that of cold-galvanized steel pipes. Let’s take a look at the differences between hot-dip galvanized steel pipes and cold-galvanized steel pipes.

Hot-dip galvanized pipes are galvanized for general steel pipes in order to improve the corrosion resistance of steel pipes. The galvanized steel pipe is divided into two types: hot-dip galvanizing and electro-galvanizing. The hot-dip galvanizing layer is thick, the cost of electro-galvanizing is low, and the surface smoothness is reduced.

The difference between hot-dip galvanized steel pipe and cold-galvanized steel pipe

The first type: cold-galvanized pipe and hot-dip galvanized pipe have a big difference in the way of operation. Zinc in hot-dip galvanizing is zinc obtained at 450 degrees Celsius to 480 degrees Celsius, and zinc in cold-galvanized steel pipes is zinc obtained by electroplating at normal temperature.

The second type: cold galvanized pipe and hot-dip galvanized pipe have a great difference in the thickness of the galvanized layer. The thickness of zinc in the hot-dip galvanized steel pipe is much thicker than the thickness of the zinc in the cold-galvanized steel pipe.

The third type: cold-galvanized pipe and hot-dip galvanized pipe have great difference in surface smoothness. The surface of cold-galvanized steel pipe is much rougher than that of hot-dip galvanized steel pipe.

The fourth type: cold-galvanized pipe and hot-dip galvanized pipe also have great differences in price. Hot-dip galvanized steel pipes are produced by regular galvanized pipe manufacturers. In order to ensure the quality of galvanized pipes, they generally In the case of galvanizing, the galvanizing method is not used, and those with relatively old equipment and small scales mostly adopt the mode of electro-galvanizing seamless steel line pipe. Naturally, cold-galvanized steel pipes are much cheaper than hot-dip galvanized steel pipes.

The fifth type: the cold-galvanized steel pipe is only one side of the galvanized steel pipe, and the hot-dip galvanized steel pipe is to be fully galvanized.

Sixth: Cold-galvanized pipe and hot-dip galvanized pipe also have great differences in adhesion. The adhesion of cold-galvanized steel pipe is much worse than that of hot-dip galvanized steel pipe because of the cold-galvanized steel pipe. The matrix and the zinc layer are independent, the zinc layer is very thin, and it is simply attached to the steel pipe base, so the cold-galvanized steel pipe is easy to fall off.

The cold-galvanized steel pipe adopts an electroplating process and is only galvanized on the outer wall of the steel pipe, and the inner wall of the steel pipe is not galvanized; the hot-dip galvanized steel pipe adopts a hot dip galvanizing process, and the inner and outer walls of the steel pipe have a zinc layer.

The difference between the hot-dip galvanized steel pipe and the cold-galvanized steel pipe shared today is here. The difference between the two is in addition to the above, the biggest difference is the corrosion resistance. The cold-galvanized steel pipe has very little galvanizing. 10-50g/m2, hot-dip galvanizing is several times higher, obviously safer.