Color steel plate powder coating

Abstract: This paper introduces the development of color steel plate powder coating technology at home and abroad, points out the difficulties of paint and coating technology that hinder the full industrialization of color steel plate powder coating, and describes the color steel plate ultra-fine powder coating and the application of ultra-fine powder coati.

0 Preface

Color steel powder coating is a major topic in the entire paint coating indust.

The development history of powder coating

The powder coating of color steel plates in Europe has developed earlier, but it has been staying at the slow coating level below 20 m/m.

Technical Problems of Powder Coatings

The biggest feature of color steel plate coating is high efficiency and low co.

Problems with powder coating equipment and processes

Compared with the unsolvable problems of powder coating thickness and flatness, color steel powder coating equipment also has a series of technical problems that must be solved and the industry has not been able to solve .

(1) Difficulty in powder application of high-speed powder coating

The line speed of color steel plate coating is very fast, usually as high as 60~180 m per minu.

(2) Coating uniformity of powder coating

The coating thickness of color steel plate coating is between 20 and 30 μm according to the relevant industry standards, and there are still a large number of products on the market whose coating thickness is much lower than the non-mandatory industry standar.

(3) Fat edge problem of powder coating

Traditional powder coating relies on electrostatic adsorption to add powder, and more powder will gather at the edge, resulting in the phenomenon of "fat edg.

(4) The problem of efficient recycling and rapid color change

Liquid color steel plate coating production lines basically have fast color changing devic.

(5) The demand for one-time baking and double-sided different color coating

Liquid color steel plate coating can usually be coated with primer and topcoat, two-coat and two-baked, and can also be coated with different coatings on the front and back into the same furnace to bake togeth.

(6) Safety issues of electrostatic powder coating

Traditional powder coating uses high-voltage static electricity to charge and adsorb du.

(7) Reconstruction and utilization of existing color steel plate liquid line

There are already about 800 liquid coating lines for color steel plates in Chi.

The above problems are technical problems that we have summarized based on the experience of others and ourselves in the course of many years of R&D practi.

Technology research and development

Our research and development of color steel powder coating is mainly divided into two aspects: one is the development of color steel powder coatings with ultra-fine powder coatings as the core; the other is the development of color steel powder coating equipment suitable for ultra-fine powde.

1 Ultra-fine color steel plate powder coating

Powder coating has the advantages of environmental protection, energy saving, high quality, high efficiency and low co.

1 Ultrafine Powder Coating Technology

The large particle size of ordinary powder coating powder makes the coating have two obvious disadvantages of poor surface flatness and too thick coating (Figure 1), which limits the further reduction of the cost of powder coatings and also limits the requirements for many high-level surfac.

The particle size of conventional powder coatings is 30~50 .

The finer the powder, the smoother the coating and the thinner the thickne.

However, if the powder is too fine, it will cause the powder to agglomerate and cannot be spray.

After years of hard work, we have used nanotechnology to completely solve the problem that ultrafine powder cannot be fluidized by agglomeration, and then invented the ultrafine powder coating technology to reduce the particle size of the powder to 10~20 .

Ultrafine powder can obtain a thin and flat coating surface, which completely solves the two major problems of poor flatness and too high thickness of powder coati.

Experiments show that for the same powder coating, the salt spray resistance test performance of the coarse powder coating of 70 μm is not as good as that of the ultrafine powder coating of 40 μm, because the minimum film thickness of the coarse powder coating of 70 μm is less than 25 μm, while The lowest point of the ultrafine powder coating of 40 μm is higher than 30 μm (F.

2 Application of ultrafine powder

Ultrafine powder solves the problem of fine powder agglomeration affecting fluidization, and can use normal spraying equipment and production lines like conventional powd.

Ultrafine powder is characterized by smooth coating and thin coati.

The coating is smooth, which improves the product quality; the coating is thin, which greatly reduces the cost of coating producti.

The ultrafine powders we invented have been used in a variety of industries, including building materials, home appliances, furniture, bicycles, auto parts, and mo.

Ultrafine powder plays a great role in the process of "painting to powder" in coating, and is especially suitable for color steel plate coati.

3 Other powder coating technologies

The color steel plate coating has its special various properti.

Color steel plate coating uses ultrafine powder, which has its special requiremen.

Both a thin coating and good hiding power are required, as well as good corrosion and weather resistan.

Our technical research and development results in color steel plate ultrafine powder are as follo.

(1) Two-coat and one-bake powder coating technology

In the color steel plate coating, the role of primer is mainly to resist corrosion and increase adhesion, while the role of topcoat is mainly to resist weathering and improve mechanical properties such as hardness and flexibili.

Primer and topcoat are used together for optimum performan.

To implement two-coating and two-bake powder coating, it will cause a particularly high cost, and it is difficult to implement in actual producti.

According to the characteristics of powder coating, we propose a new process of two-coating and one-baking, so as to achieve the coating effect of two-coating and two-baking of liquid coating with the production cost of one baki.

(2) Formulation of powder coating for color steel plate with high corrosion resistance

The color steel plate coating is very th.

Thinner coatings require higher corrosion resistan.

Conventional powder coating resins are difficult to meet the corrosion resistance requirements of color steel plates in very thin conditio.

It is necessary to make a fuss about resins and formulations to improve the corrosion resistance of coatin.

(3) High flexibility color steel plate powder coating formulation

Color steel plates are all processed and formed, and the flexibility of the coating is very important for the application of color steel plates, especially in home appliances and other produc.

Powder coatings are inherently more flexible than liquid coatings of similar resins due to the high molecular weight of the res.

Nonetheless, a powder coating with better flexibility, especially with very good flexibility while maintaining a higher hardness, is still an advantage of powder coati.

(4) Formula of ultra-high hardness color steel plate powder coating

Powder coating has a much higher hardness than liquid coating, which is a performance that cannot be achieved by liquid coating of color steel plate, and is also an advantage of powder coati.

We use nanotechnology to prepare color steel products with 5H hardness, which is an unprecedented product in the color steel coating indust.

(5) Quanbonding metal powder coating technology

We have carried out inorganic and organic multi-layer coating surface treatment on metal pigments, which purposefully improved the conductivity of metal pigments and the compatibility with powde.

After a special bonding production process, the bonding rate was obtain.

Very high metal powder coating products, can achieve more than 10% or even 20% aluminum powder and pearl powder content products and have good performan.

We call it all-bond metal powder coati.

The color steel plate metal powder coating prepared by Quanbangding metal powder coating technology can stably produce various metal color steel plates, including phantom color steel plate products (Figure

Color steel coating is a big indust.

After decades of development, liquid color steel coating has many mature and stable coating varieties, and it has long been a very mature indust.

Powder coating has obvious advantages in coating performance compared to liquid coating due to the relatively large molecular weight of res.

Although color steel powder coating (Figure 5) has huge development prospects, it is basically in a state of undevelop.

In terms of raw material technology, powder coating formulation technology, e.

, it is urgent to increase efforts to develop and form a new category as soon as possib.

indust.

2 New breakthroughs in color steel coating equipment technology

The breakthrough of color steel plate powder coating equipment and related technologies is another prerequisite for the realization of "paint to powder" in color steel plate coati.

Because we are very aware of various technical problems that have not been successful at home and abroad, we carry out technical research on each technical probl.

In the research and development process of nearly ten years, we started from renting a color aluminum plate coating line to try slow powder coating, to building a high-speed circulating steel strip equipment for high-speed spraying tests, and then successively in two large color steel plat.

The company did an on-line test, and finally spent another two years perfecting the details, finally preparing and installing the official commercial coating equipment on the actual liquid coating li.

The previous work was mainly aimed at a series of problems encountered in the past practice in foreign countries, but after the application on the production line in the later stage, it was found that there were too many unexpected industrialization technical problems, and every seemingly small problem was a hindran.

The technical problems that must be solved in the industrialization of color steel plate powder coating have even become technical problems that can only be solved for a long ti.

Some of the problems we encountered in equipment technology and the results of technical research and development are summarized as follo.

(1) Invented a powder coating machine that can be installed on the existing liquid color steel coating line (F.

6), without building a new coating line, the color steel coating can be realized on the original liquid li.

"Paint to Powde.

(2) The new electrostatic powder coating technology is completely different from the traditional spray gun, which avoids the problem that the traditional spray gun cannot powder at high speed, so that the powder coating speed is not limited, and can run at the original line speed of the liquid line, up to 180 m /m.

(3) A set of powder coating machine is divided into two sets of front coating machine and back coating machi.

The front coating machine can coat base powder and flour at one time, and the two coatings are baked together; at the same time, the back coating is carried out on the ba.

Powder coating, the front and back sides are baked and cured togeth.

The so-called two coats and one bake, and three coats and one ba.

(4) The use of special equipment and technology treatment greatly reduces the fat edge of powder coating, and does not affect the rewinding of large steel coils at a.

(5) The coating uniformity of the equipment is good and can be applied thinly; the use of superfine powder can obtain a frontal coating of 5+20 (total 25) μm of frontal primer and flour, and various properties are better than the same liquid coating, while The cost of painting is significantly reduc.

(6) The coating machine adopts nitrogen protection operation, which completely avoids the potential safety hazard of dust explosion caused by electrostatic coati.

The development process of color steel plate powder coating equipment is actually a

The discovery and solution of related technical problems is a process of repeated cycles, especially in the later stage, when debugging equipment on a large-scale production coating line, any small problem may bring huge problems on a high-speed production line, and the production of color steel plate coating requires a high degree of The stability and reliability of the system, and many problems cannot be predicted and discovered without large-scale production practi.

We are honored to have received active support from many color steel coating customers during the test run, so that we were able to gain relevant knowledge and solve proble.

Conclusion

Color steel plate coating is a huge industry, and the "paint to powder" of color steel plate coating has great prospec.

Advances in technology have proved that powder coating has the advantages of environmental protection, safety, and superior performan.

To fully replace liquid coating, it is also necessary to achieve low production cos.

A uniform thin coating is k.

The continuous progress and breakthrough of ultra-fine powder coating technology and coating equipment technology will make the color steel plate powder coating ultimately achieve the goal of lowering the coating cost than liquid coating, and truly achieve "safety, environmental protection, low cost, and good performance", thereby Promote the rapid development of "paint-to-powder" for the entire color steel plate coati.