Process characteristics of galvanized steel pipe

Regarding the processing technology of galvanized steel pipes, many people are curious about the processing technology.

1. Optimization of sulfate zinc plating

The advantages of sulfate galvanizing are that the current efficiency is as high as 100% and the deposition rate is fast, which is unmatched by other galvanizing processes. Because the crystallization of the coating layer is not detailed enough, and the dispersing ability and deep plating ability are poor, it is only suitable for electroplating pipes and wires with simple geometric shapes. The sulfate electro-galvanizing iron alloy process optimizes the traditional sulfate galvanizing process, only the main salt zinc sulfate is retained, and the rest of the components are discarded. An appropriate amount of iron salt is added to the composition of the new process formula to form a zinc-iron alloy coating from the original single metal coating. The reorganization of the process not only brings forward the advantages of high current efficiency and fast deposition rate of the original process but also greatly improves the dispersion ability and deep plating ability. In the past, complex parts could not be plated, but now simple and complex parts can be plated, and the protective performance is 3 to 5 times higher than that of a single metal. Production practice has proved that for continuous electroplating of wires and pipes, the grains of the coating are finer and brighter than the original ones, and the deposition rate is faster. The thickness of the coating meets the requirements within 2 to 3 minutes.

2. Conversion of sulfate zinc plating

Sulfate electro-galvanized iron alloy only retains zinc sulfate, the main salt of sulfate galvanizing, and other components such as aluminum sulfate, alum (aluminum potassium sulfate), etc. can be treated with sodium hydroxide to form insoluble hydroxide precipitation. Remove; for organic additives, add powdered activated carbon to remove by adsorption. Tests have shown that aluminum sulfate and aluminum potassium sulfate are difficult to be completely removed at one time, and have an impact on the brightness of the coating, but it is not serious and can be consumed along with it. The conversion is completed when the content of the ingredients needs to be supplemented.

3. Fast deposition rate and excellent protection performance

The current efficiency of the sulfate electro-galvanized iron alloy process is as high as 100%, and the deposition rate is unmatched by any galvanizing process. The running speed of the fine tube is 8-12 m/min, and the average thickness of the coating is 2 m/min, which is difficult for continuous galvanizing. achieved. The coating is bright and delicate. According to the national standard GB/T10125 "artificial atmosphere test - salt spray test" method, 72 hours, the coating is intact and unchanged; 96 hours, a small amount of white rust appears on the surface of the coating.

4. Unique cleaner production

The galvanized steel pipe adopts the sulfate electro-galvanized iron alloy process, which means that the production line slot and the slot are all perforated straight through without any carry-out or overflow of the solution. Each process in the production process consists of a circulatory system.

Each tank solution, namely acid-base liquid, electroplating liquid, light-emitting and passivation liquid, etc., is only recycled and not leaked or discharged to the outside of the system. The production line has only 5 cleaning tanks, which are regularly discharged by recycling, especially passivation. No wastewater production process without post-cleaning.

5. The particularity of electroplating equipment

The electroplating of galvanized steel pipe is the same as electroplating of copper wire, which belongs to continuous electroplating, but the electroplating equipment is different. The iron wire is a plating tank designed with its slender strip characteristics, the tank body is long and wide but shallow. During electroplating, the iron wire is pierced through the hole and spread out on the liquid surface in a straight line, keeping the distance from each other. The galvanized steel pipe is different from the iron wire, it has its unique features, and the groove equipment is more complicated.

The tank body is composed of upper and lower parts, the upper part is the plating tank, and the lower part is the solution circulation storage tank, forming a trapezoid-like tank body with a narrow upper and a lower width. There are two through holes at the bottom of the tank which communicate with the lower storage tank and form a plating solution circulation and reuse system with the submerged pump. Therefore, the galvanized steel pipe is the same as the iron wire electroplating, and the plating parts are dynamic and different from the iron wire electroplating, the plating solution of the electroplated galvanized steel pipe is also dynamic.

After understanding the technological characteristics of so many galvanized steel pipes, I believe that I have a different understanding of galvanized steel pipes.