How many years can hot-dip galvanized screws not rust? This is also a perennial problem, there are many decisive factors, but ultimately depends on the quality of hot-dip galvanized screws, so the data collected here is based on the national standard hot-dip galvanized screws anti-corrosion years to analyze, for those who do not meet the national standard hot-dip galvanized screws, here for the time being.

The anti-corrosion life of hot-dip galvanized screws refers to a standard hot-dip galvanized screw product, first of all, the thickness of the zinc layer is up to standard.

How many years do not rust, of course, with the thickness of the zinc layer.

If the national standard requirements in the galvanized layer is 80 microns, the result is that some companies in order to save costs, only 30 microns plated, it will not take long to rust.

Usually the thickness of the galvanizing layer is 5 to 15μm, and the hot-dip galvanizing layer is generally more than 35μm, and this 35 micron is the lowest data, normal our daily use of hot-dip galvanized screws, its average data is 60 microns, and some hot-dip galvanized screws even up to 200μm.

Good hot-dip galvanized screw, its surface zinc layer coverage ability is very good, and the galvanized layer is also very uniform and tight, you can not see the debris on top, from a distance, just like Dacromet bright and beautiful.

We know that zinc in the atmosphere corrosion environment, it will have a layer of chemical protection mechanism, hot plating outer layer can effectively delay the corrosion of the bolt time, when the zinc layer is damaged, the bolt body will be exposed, so it is dangerous.

A complete hot-dip galvanized screw, the surface of the zinc will produce electrochemical protection on the bolt matrix, the standard potential of zinc is -0.76V, and the standard potential of iron is -0.74V, when zinc and iron form an effect, the zinc layer becomes an anode end, against the corrosion environment, but the formation of the cathode end, protected. The formation of hot dip galvanizing is just a process of zinc and iron alloy dissolution, after the formation of galvanized layer on the surface of the bolt, zinc and iron are closely combined, which can play an anti-corrosion role. So how long does it take?

Let's first look at different environments, if it is used indoors, hot-dip galvanized screws, as long as the zinc layer is not damaged, hot-dip galvanized screws can not rust in 50 years, that is to say, its anti-corrosion life is 50 years or more.

If it is used outdoors, hot-dip galvanized screws can also be done for 20 years without rust, if it is used in harsh conditions in coastal areas, hot-dip galvanized screws can be done for 15 years without rust.

If it is used directly under the water, it can be used for about five years without rust, why say about it, because the use of bolts under water is rarely, and the actual use is temporarily lacking of data reference, and its anti-corrosion life can only be determined according to the salt spray test effect of hot-dip galvanized screws.

The above data can only be used as a reference, and there may be various uncertain factors leading to data errors in practical applications, so please analyze it rationally.