What is galvanized steel pipe?

Galvanized pipes, also called galvanized steel pipes, are divided into hot-dip galvanized and electro-galvanized pipes. The hot-dip galvanized layer is thick, the coating is uniform, the adhesion is strong, 

and the service life is long. Electroplating is less expensive, has a less smooth finish and is significantly less resistant to corrosion than hot-dip galvanized tubing.

hot-dip galvanized pipe

The molten metal reacts with the ferrous substrate to form an alloy layer that bonds the substrate and coating. In hot-dip galvanizing, the steel pipe is first pickled to remove iron oxide on the steel pipe surface. 

After pickling, it is washed with an aqueous solution of ammonium chloride, zinc chloride, or a mixed aqueous solution of ammonium chloride and zinc chloride. hot dip coating tank. 

Hot-dip galvanizing has the advantages of uniform coating, strong adhesion and long service life. Most northern processes are directly galvanized with galvanized strip.

cold galvanized pipe

Cold galvanizing is electro-galvanizing. The proportion of galvanizing is very low at 10-50 g/m² and the corrosion resistance is far worse than that of hot-dip galvanized pipes. 

Most threaded JDG tubing is not electro-galvanized (cold coated) by traditional galvanized tubing manufacturers to ensure quality. 

Electro-galvanized steel sheet is used only by small and medium-sized enterprises with outdated equipment, and the price is relatively low by nature. 

It is forbidden to use cold galvanized steel pipes as water supply pipes in new houses.

Hot dip galvanizing process:

Workpiece degreasing → water washing → pickling → water washing → drying Preheat solvent immersion flux, hot-dip galvanizing → cooling → finishing → water washing → drying → passivation test

Cold galvanizing process:

Chemical degreasing → water washing → hot water electrolytic degreasing → water washing → water washing → heavy corrosion galvanizing → water washing → water washing → whitening → 

water washing → dry passivation

Appearance hot-dip galvanized and cold-galvanized

The cold galvanizing looks smoother and brighter, and the color passivation layer is yellow-green and bright. 

The plating is bluish white or white, the white plating after passivation treatment is green, and the white plating after passivation treatment looks colorful under sunlight. 

Corners of complex workpieces are prone to "electrical burns" and darken. The zinc layer is thicker in this part. 

The current gray area below the current dead zone is likely to form at the negative corner, and the zinc layer in this area is relatively thin. Zinc lumps and agglomerates can be seen all over the workpiece.

Hot-dip galvanizing has a slightly rougher appearance than electro-galvanizing and is silver-white. Machining watermarks and a few wart drops seem likely, especially at one end of the workpiece. 

With hot-dip galvanizing, the zinc layer is many times thicker than with electro-galvanizing, and the corrosion resistance is many times higher than with electro-galvanizing.

The advantages of the galvanized tube are:

First, it protects the surface of the galvanized pipe after hot-dip galvanizing, and can easily cover the deep parts such as cavities and corners of the pipe, 

which are difficult for galvanizing to penetrate, and protect the whole galvanized pipe.

Second, the impact and wear resistance of galvanized pipe after galvanizing is very good. This is because the hardness of the galvanized layer is higher than that of steel, 

so the impact resistance and wear resistance after hot-dip galvanizing is very good. 

In addition, the biggest advantage of zinc plating is that the zinc layer is relatively thick at the corner and has good toughness and wear resistance, 

while other coatings are often the thinnest and most difficult to apply at this corner, making them prone to scratching.

Third, another key feature of hot-dip galvanizing is that sometimes major mechanical damage causes part of the zinc layer to fall off, exposing the base iron. 

In this case, however, it exhibits a different spirit of sacrifice than the surrounding layer of zinc and other coatings, protecting the steel from corrosion.

Finally, regarding the durability and aesthetics of hot-dip galvanizing, the main mechanism of durability is the thickness of the coating in a given environment. 

The thickness of the coating is determined by the thickness of the galvanized pipe. The thicker the galvanized pipe, the easier it is to coat. 

Second, from an aesthetic and artistic point of view, the paint is applied over the galvanized layer in some very corrosive environments. 

If the correct coating system is selected, the installation is easy and the anti-corrosion effect is very good.

Shanghai Huagang Steel Co., Ltd. with a good reputation, high-quality products, solid strength and lower price is famous in the country. Our company has rich experience in trading as we are engaged in domestic trading for more than 20 years.

In 2008, we opened the market abroad. Our company is the collection of processing and operating. And we have a high supply ability. Our main products are stainless steel, galvanized steel, carbon steel and etc. These products apply to engineering, coal mining, textile, electric power, boiler, machinery, military industry and other fields.

F&Q

Q: Do you provide free samples?

A: Yes, we can provide a free sample for testing, buyer should bear all the shipping costs.

Q: Do you accept small orders?

A: You don't need to worry about this problem, just consult

Q: Do you accept third-party inspection? Which ports are accepted for delivery?

A: Yes absolutely we accept. It can be delivered from Qingdao, Tianjin, Shanghai and other ports.

Q: What are the advantages of your company?

(1): Prime quality and reasonable price.

(2): Wide excellent experiences with after-sale service.

(3): Every process will be checked by the responsible QC which insures every product's quality.

(4): Professional packing teams which keep every packing safe.

(5): Trial order can be done in one week.

(6): Samples can be provided as per your requirements.

Q: How can we get your price?

A. We need the below information to quote for you:

1. Product Name

2. Standard

3. Material Grade (Chemical Composition)

4. Dimension

5. Quantity

6. The Drawing for Special Parts