What is pre-coated metal sheet for insulated sandwich panel?

Development trend of pre-coated insulation sandwich panel.

 

The precoated metal sheet sandwich panel not only has the properties of high mechanical strength and easy forming of steel materials, but also has the good decorative and corrosion resistance of coating materials. The precoated metal sheet sandwich panel is a new material which is highly praised in the world. With the progress of science and technology, the enhancement of environmental awareness and the improvement of people's living standards, the precoated metal sheet sandwich panel activity room shows more and more strong vitality and broad market prospects, and is favored by construction, home appliances, electromechanical, transportation, interior decoration, office appliances and other industries.

 

The core of precoated steel sandwich panels is mainly phenolic foam, polystyrene, extruded polystyrene, rigid polyurethane, three polyester and rock wool, etc. phenolic foam has excellent fire resistance and heat preservation properties. It is irreplaceable for other materials. For example, phenolic foam insulation is more than 2 times of polyphenylene, and its fire resistance is higher than that of polyurethane. When polyamic acid is burned, hydrogen cyanide will be released. thick smoke.

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With the national attention to building fire prevention and the introduction of relevant laws, it is believed that phenolic insulated sandwich panel will create a blue sky in the construction field.

 

Most of the sandwich panels are made of color steel, and the development trend of precoated metal sheet is as follows:

 

1. With high-quality substrate, the requirements for the surface, shape and dimensional accuracy of the substrate are getting higher and higher. For outdoor use, such as small zinc flower flat hot-dip galvanized steel coil, non zinc flower flat hot-dip galvanized steel coil, such as zinc alloy hot-dip galvanized steel coil rising in time, for indoor use, such as electric galvanized steel coil, film coated cold-rolled plate and aluminum coil.

 

2. Improve the pretreatment process and the pretreatment liquid. The equipment quantity is small and the cost is low, which becomes the mainstream process. Continuously improve the stability, corrosion resistance and environmental protection performance of the pretreatment.

 

3. Development of re coating, improvement of general polyester, polyvinylidene fluoride (PVDF) and plastisol, obtaining super color reproducibility, UV resistance, sulfur dioxide resistance, corrosion resistance improvement, development of pollution resistance, heat absorption and other functional coatings.

 

4. The equipment of the unit is more perfect, such as using new welding machine, new roller coating machine, improving curing furnace, equipped with advanced automatic instruments, etc.

 

5. Because the cost of cold embossing is lower than that of hot embossing, which has the characteristics of beauty, three-dimensional sense and high strength, the production technology of cold embossing has become the development trend.

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The uncoiling forming of precoated metal sheet sandwich panel

 

In the production of metal skin insulated sandwich panel, continuous production line is mainly adopted, which is simple, light and easy to operate.

 

The uncoiler forming of color steel sandwich panel means that the uncoiler used is full-automatic hydraulic uncoiler, and the speed of uncoiler is subordinate to the speed of double belt machine, so as to ensure the straightness of steel plate and reduce the resistance of double belt machine. The forming section is composed of multi-component rollers to reduce the resistance of the double belt machine. Each group of forming rollers controls the forming of each type of steel plate. In principle, one plate type will have one composition roller, but more plate types can also be pressed by combination, which must be considered in the design process of roller.

 

In order to improve the production efficiency and reduce the workload of workers when changing rollers, the more advanced forming section adopts the way of hydraulic lifting or rail moving roller changing, which can change the forming rollers of different plate shapes in a short time. This kind of equipment has large investment and few factories in China, but it is a development direction. The side wheel combination of forming section is also a very important part. It can change the form of spigot, increase the variety of products and improve the grade of products.

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What's the difference between precoated metal sheet and plastic steel?

 

The base plate of precoated steel plate is cold-rolled base plate, hot-dip galvanized base plate and electro galvanized base plate. Coating types can be divided into polyester, silicon modified polyester, vinylidene fluoride and plastisol. The surface state of the precoated steel plate can be divided into coating plate, embossing plate and printing plate. The color coated steel plate is widely used in construction appliances, transportation and other industries. For the construction industry, it is mainly used in steel structure factory buildings, airports, warehouses, refrigeration and other industrial and commercial buildings, such as the walls and doors, and civil buildings use less color steel plate. The difference between it and plastic steel is that the material composition is different. The magnet can be sucked.

 

Strictly speaking, plastic steel and color steel cannot be well distinguished in metal characteristics and surface treatment, because they are very similar; therefore, the market is mainly in profile structure.

 

Discussion on the construction of precoated metal sheet 

 

At the end of 1980s, China began to build color steel plate units, most of which were built in iron and steel plants and joint ventures. Color steel plate process equipment was basically imported from abroad. By 2000, the domestic color steel plate had reached 1.73 million tons, with overcapacity. Baosteel, Angang, Shougang, Tanggang, Jigang, Kungang, Hangang, WISCO, Pangang and other large state-owned iron and steel enterprises have higher unit capacity and equipment level, and have successively built color steel plate units with foreign technology and annual production capacity of 120000 ~ 170000 tons.

 

At the same time, most of the precoated steel plate production invested by many private enterprises adopts domestic equipment with small production capacity, but it is quick to start and low in investment. Its products are mainly for building materials and decoration industries. In addition, foreign investment and Taiwan investment have also landed to build color coating units, but most of them are concentrated in coastal areas. Since 1999, with the prosperity of color coating plate market, the production and consumption of color coating plate has entered a rapid growth period. From 2000 to 2004, the production increased at an average rate of 39.0%. By 2005, the production capacity of color coated boards in China was more than 8 million tons / year, and a number of color coated units were under construction, with a total production capacity of more than 9 million tons / year.

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What is the structural form of precoated steel sheet?

 

Before forming, there are many types of coiled materials. The most commonly used types are 820, 840, 900, etc. its composition and structure are: protective film, polyester paint, galvanized layer, steel plate (divided into cold-rolled plate and hot-rolled plate), the same order on the back.

 

There are many brands of precoated steel plate with different advantages and disadvantages. Common examples: Baosteel, Dashui, Xinyu, Zoje, Zhonggang, etc., with excellent quality.

 

General engineering can be divided into single board and composite board, composite board is divided into rock wool composite board and polystyrene composite board. The single board is mostly used in workshop or canopy: some single boards will be installed with rock wool, which is called "field composite".

 

The composite plate type wallboard is mostly 950 type, and the roof 970 type or 960 type. 760, 820, 840, 900, or 960 are common for single boards, of which 760 and 820 are fixed by brackets and other types are fixed by self-tapping screws.

 

760, 820 and 840 are mostly used as top plates, 900 are used as wall panels, 127 or 960 are used as panels or top inner anti hanging panels for decoration.

 

Color steel accessories are also indispensable in the project. The internal corners, external corners, door and window openings, small gutters, secondary contraction joints, etc. of the ridge tiles are mostly fixed with rivets and sealed with glue.

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The composition and application of precoated steel sheet

 

1. The base plate of color steel plate can be divided into cold-rolled base plate, hot-dip galvanized base plate and electro galvanized base plate.

 

2. Coating types of color steel plate can be divided into: polyester, silicon modified polyester, vinylidene fluoride, plastisol.

 

3. The color of color steel plate can be divided into many kinds according to the user's requirements, such as orange, cream, dark sky blue, sea blue, crimson, brick red, ivory, porcelain blue, etc.

 

4. The surface state of color steel plate can be divided into coating plate, embossing plate and printing plate.

 

5. The market uses of color steel plate are mainly divided into three parts: construction, home appliances and transportation. Among them, the construction sector accounts for the largest proportion, followed by the home appliances industry, and the transportation industry only accounts for a small proportion.

 

The precoated steel sheet for building is generally based on hot-dip galvanized steel plate and hot-dip aluminum zinc steel plate. It is mainly processed into corrugated plate or polyurethane composite sandwich plate, which is used for building roofs, walls and doors of industrial and commercial buildings such as steel structure workshops, airport warehouses, freezers, etc.

 

The color board of household appliances is generally based on galvanizing and cold plate, which is used to produce refrigerators and large air conditioning systems, freezers, bakers, furniture, etc.

 

In the transportation industry, galvanizing and cold plate are generally used as the base plates, mainly for oil pan, automobile interior parts, etc.

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The market uses of color coated steel plate are mainly divided into three parts: construction, household appliances and transportation.

 

1. With the progress of science and technology, the enhancement of environmental awareness and the improvement of people.

 

2. Precoated steel plate has the advantages of light weight, high strength, heat preservation and insulation, beautiful and durable. It is a high-grade building integrated with architecture and decoration.

 

3. The market uses of precoated steel plate are mainly divided into three parts: construction, household appliances and transportation, among which the construction field accounts for the largest proportion, followed by household appliances industry, while the transportation industry only accounts for a small proportion. The color steel plate for construction is generally based on hot-dip galvanized steel plate and hot-dip aluminum zinc steel plate, which is mainly processed into corrugated plate or composite sandwich plate with polyurethane, and then used to build steel structure workshops, airports Roofs, walls and doors of industrial and commercial buildings such as warehouses and freezers. The color steel plate for household appliances is generally based on galvanizing and cold plate. It is used to produce refrigerators and large air conditioning systems, freezers, bakers, furniture, etc. in the transportation industry, galvanizing and cold plate are generally used as the base plate, mainly for oil pan, automobile interior parts, etc.

 

4. Excellent material, environmental protection, pollution-free, cheap, convenient, beautiful and other advantages of color steel plate in one, by the user's praise, his future will be a bright.

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What are the problems of precoated metal steel plate?

 

Here is a detailed introduction:

 

1. Although the production capacity of hot-dip galvanized base plate for building materials with the largest consumption is very large, there is a lack of good base plate such as zinc free flat hot-dip galvanized steel coil and zinc alloy coated steel coil;

 

2. The variety and quality of domestic coatings can not fully meet the demand, the price of imported coatings has reduced the competitiveness, the plastic film needed for the film pasted color board still needs to be imported, lacking the high-grade color coated board with thick coating, high strength and rich colors;

 

3. The products are not standardized, resulting in serious waste of resources. There are too many low-capacity units with a capacity of less than 40000 tons / year, and there are problems in product quality and environmental protection;

 

4. There are too many newly built color coating units in China, which far exceeds the market demand, resulting in the low operating rate of many color coating units, or even the shutdown.

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Characteristics and properties of precoated metal sheet

 

Precoated metal sheet is a product made of cold-rolled steel plate and galvanized steel plate after surface chemical treatment (roll coating) or composite organic film (PVC film), and then baked and solidified. Some people also call this product "pre roll coating color steel plate" and "plastic color steel plate". Color steel plate products are produced in continuous production line by the manufacturer, so it is also called precoated steel plate coil. Color steel plate not only has the properties of high mechanical strength and easy forming of steel material, but also has good decorative and corrosion resistance of coating material. Color steel plate is a new kind of material which is highly praised in the world. With the progress of science and technology, the enhancement of environmental awareness, and the improvement of people's living standards, color steel plate mobile houses show more and more strong vitality and broad market prospects, which are favored by building electrical appliances, mechanical and electrical equipment, transportation, interior decoration, office appliances and other industries.