Hot galvanized plate surface defects

Hot galvanized plate is a long Word plate, hot galvanized plate has a lot of advantages, but there will be some drawbacks corresponding. Manufacturers from galvanized sheet production to the store will have some drawbacks.

1, Galvanized layer off: off the main reasons many, including zinc coating surface oxide, silicon compounds, cold rolling emulsion dirty, the OF segment oxidizing atmosphere and shielding gas dew point is too high strip wok temperature partial low, so many factors can cause the shedding of the zinc coating.

2, there will be a white embroidered and the formation of dark spots: spots is a result of the further oxidation of white embroidery. White embroidered causes of a passivation film thickness enough or uneven; B, the surface of the galvanized steel sheet does not have an oil coating or coiling the strip surface residual moisture; c, passivation is not completely dried; transport or storage in damp or dry in the rain; e finished storage time is too long; f, galvanized sheet and other acid and other corrosive media contact or stored together. Finished in the library most common can only be stored for three months, put the long time oxidation.

In addition to the above two points defects, as well as scratches, passivation spot, zinc tablets, webbing, air knife streak, air knife scratches, exposed steel, inclusions, mechanical damage, poor performance steel base side of the wave, buckling substandard size, imprint, zinc layer thickness clashes, such as roller printing defects.

Galvanized sheet in a lot of industries are likely to use, not the same flaws exposed in different industries, such galvanized sheet prices also may differ, but I believe that we will in the future continue to progress to make up for these deficiencies.

Weled steel pipe specification, Standard and identification

Welded steel pipe (steel pipe manufactured with a weld) is a tubular product made out of flat plates, known as skelp, that are formed, bent and prepared for welding.