Galvanized Steel Pipe Rust
Galvanized steel pipe rust is mainly for zinc soluble in acid and also be dissolved in alkali, so call it gender metal. Zinc in the dry air is almost no change. In humid air, the zinc surface will generate a dense film of basic zinc carbonate. Containing sulfur dioxide, hydrogen sulfide and marine atmosphere, the poor corrosion resistance of zinc, especially in hot and humid atmosphere containing organic acids, the zinc coating can easily be corrosion. Zinc standard electrode potential of-0.76V, the steel substrate, the zinc coating is anodic coating, which is used to prevent the corrosion of iron and steel, the pros and cons of its protective properties of coating thickness relationship is great.
Zinc coating, passivation, staining or coating retaining light agent, can significantly improve the protective and decorative. Zinc oxide in the air, the surface of the formation of white rust, this situation is normal. Depends on your strip is hot dip galvanized or electro-galvanized, hot dip galvanized, then because of the relatively thick layer of zinc to generate white rust does not affect the normal warranty, because the oxidation rate of zinc in the air is very slow. Electro-galvanized is not easy to say. Not see the rust will not be affected. When you want to save the galvanized steel to be careful not to put wet and hot weather ventilation is very easy to mold, some of the winter, then adhere to the longer.
Galvanized Steel Pipe technical requirements
For hot dip galvanized steel pipe quality inspection process, the most main point is application performance of galvanized steel pipe.
The bending point of the hot dip galvanized refers to the phenomenon of a metal material having a yield, the degree of bend of the specimen in galvanized steel originally molding very important, because it can test a galvanized steel pipe by the external pressure when the reaction, if the test galvanized steel pipe pressure critical point, we can be to appropriate reinforcement galvanized steel pipe to greater affordability according to customer requirements.
If power down occurs, should distinguish between upper and lower yield point. The upper yield point is the sample to yield the power fell for the first time before the maximum stress occurs; lower yield point is the minimum stress when excluding the initial transient effect, the yield phase. The index of hardness metal material to resist the hard objects indentation the ability of the surface, known as hardness.
Depending on the test methods and the scope of the hardness can be divided into Brinell hardness, Rockwell hardness, Vickers hardness, Shore hardness, micro-hardness and high-temperature hardness. Commonly used for pipe Brinell, Rockwell, Vickers hardness.
Post time: Sep-20-2019