First, the production process of hot-dip galvanized steel pipes
Hot-dip galvanized steel pipes, also known as hot-dip galvanized pipes, are steel pipes that are galvanized to improve their performance. The principle of its processing and production is to react molten metal with the iron matrix to produce an alloy layer, thereby combining the matrix and the coating. So how are hot-dip galvanized steel pipes processed? The process flow of hot-dip galvanized steel pipes is divided into the following steps:
1. Alkaline washing: Some steel pipes have oil stains on the surface and need to be alkaline-washed.
2. Pickling: Use hydrochloric acid for pickling to remove the oxide scale on the surface of the steel pipe.
3. Rinsing: This is mainly to remove residual acid and iron salts attached to the surface of the steel pipe.
4. Immersion aid: The role of the flux is to remove all impurities from the surface of the steel pipe, ensure that the steel pipe is in clean contact with the zinc liquid, and form a good coating.
5. Drying: This is mainly to prevent the steel pipe from exploding when it is immersed in the zinc pot.
6. Hot-dip galvanizing: The temperature of the zinc liquid in the zinc pot is strictly controlled at 450±5℃. The steel pipe is placed in the galvanizing furnace and rolled into the three zinc-immersing spirals in the galvanizing machine. The three spirals are in different phases so that the steel pipe is tilted on the spiral. As the spiral rotates, the steel pipe moves downward while forming an inclination angle, and then enters the zinc liquid, and continues to move downward, automatically falling on the slide rail in the zinc pot; when the steel pipe is lifted to the surface of the magnetic roller, it will be sucked and moved to the drag roller.
7. External blowing: The steel pipe passes through the external blowing ring, compressed air, and blows away the excess zinc liquid of the steel pipe to obtain a smooth surface.
8. Drag out: Appropriately reduce the drag-out speed to control the amount of zinc and reduce zinc consumption.
9. Internal blowing: Remove excess zinc liquid on the inner surface of the steel pipe to obtain a smooth inner surface, and the removed zinc liquid is formed into zinc powder for recovery.
10. Water cooling: The temperature of the water cooling tank is controlled at 80℃ to cool the galvanized pipe.
11. Passivation: The passivation liquid is sprayed and blown around the finished pipe to passivate the surface of the pipe. After the external blow ring, the excess passivation liquid is blown off with compressed air.
12. Inspection: The galvanized steel pipe falls on the inspection stand. After inspection, the leaked pipe is placed in the waste basket, and the finished pipe is packaged and stored.
Second, what are the advantages of hot-dip galvanized steel pipes?
As a commonly used steel pipe building material, the advantages of hot-dip galvanized steel pipes are mainly reflected in the following aspects:
1. Low processing cost: The cost of hot-dip galvanizing anti-rust is lower than that of other paint coatings.
2. Durable: In suburban environments, the anti-rust thickness of standard hot-dip galvanized steel pipes can be maintained for more than 50 years without repair; in urban or offshore areas, the standard hot-dip galvanized anti-rust layer can be maintained for 20 years without repair.
3. Good reliability: The galvanized layer and the steel are metallurgically combined and become part of the steel surface, so the durability of the coating is more reliable.
4. Strong toughness of the coating: The galvanized layer forms a special metallurgical structure that can withstand mechanical damage during transportation and use.
5. Comprehensive protection: Every part of the plated part can be galvanized, even in recesses, corners, and hidden places.
6. Save time and effort: The galvanizing process is faster than other coating construction methods and can avoid the time required for painting on the construction site after installation.
7. Low initial cost: In general, the cost of hot-dip galvanized steel pipes is lower than that of applying other protective coatings. The reason is simple. Other protective coatings such as sandblasting and painting are labor-intensive processes, while hot-dip galvanizing processes are highly mechanized and efficient.
8. Simple and convenient inspection: The hot-dip galvanized layer can be tested visually and with a simple non-destructive coating thickness gauge, which is convenient for inspection.
Post time: Nov-15-2024