How hot-dip galvanized screws improve the surface quality of zinc coatings

For many years, hot-dip galvanized screws can be divided into low carbon steel wire for general use and medium and high carbon steel wire edm for special purpose. The hot-dip galvanizing of steel wire usually uses a flux method, but the hydrogen recovery method is rarely used. The hydrogen recovery process has been announced as a new technology developed based on continuous hot-dip galvanizing of steel strips.

However, due to some technical titles, it has not been implemented so far. The flux method is mainly used for hot-dip galvanizing of steel pipes. In the normal zinc plating temperature range (445 ~ 465 ℃), increasing the temperature of the zinc solution can increase the activity of the zinc solution, improve the surface quality of the zinc coating, and improve the reflow of the zinc solution to reduce the coating components. In addition, it can shorten the galvanizing time and increase the production capacity of the galvanizing pot. Excessive galvanizing temperature can easily cause deformation of the steel pipe.
 
The process of galvanizing steel pipe using the flux method is similar to the process of galvanizing steel machining plate using the flux method. Because the original pipeline is usually free of oil pollution without degreasing process, it directly enters the pickling process. When pickling, the pipe is first hoisted into the first pickling tank for pre-pickling. It is then suspended in a second pickling tank for pickling, and all iron oxide scale can be removed, usually using hydrochloric acid or sulfuric acid heated to 50-60 ° C.

The concentration of the pickling solution is 10% -20%, and the effect is good. The pickling time is determined according to the appearance of iron oxide scale on the steel pipe. The pickling process can be accelerated by often connecting the steel pipes in series. Therefore, the raised wooden strips on the bottom and side walls of the pickling tank are conducive to the rolling of the steel pipe in the acid solution.

china non-standard fasteners cnc machining shop

The non-standard width range of our products can be divided into auto fasteners, mechanical fasteners, construction fasteners, power fasteners, railway fasteners, household electrical appliances fasteners and chemical fasteners.
Product standards including DIN, ISO, GB and ASME/ANSI, BS, JIS AS. Main levels of carbon steel: 4.8, 4.8, 6.8, 8.8, 10.9, and 12.9 grade, the main material of stainless steel SS201, SS304, SS316 and various kinds of special stainless steel and other.