Material for ventilation ducts            

Now there are many ventilation duct materials on the market, so how should we choose?

1. Thin steel plate

Sheet steel is the main material for making ventilation ducts and components. Generally, ordinary sheet steel and galvanized steel sheet are commonly used. Specifications are expressed in terms of short side, long side and thickness. Commonly used sheets have a thickness of 0.5mm to 4mm, and specifications of 900mm × 1800mm and 1000mm × 2000mm.

Ordinary thin steel plate: Ordinary thin steel plate has two types: plate and coil, and the specifications of the plate are shown in Table 2-5. This kind of steel plate belongs to B-type steel, which is cold and hot-rolled steel plate with steel number Q235B. It has good processing performance and high mechanical strength, and the price is cheap.

Galvanized steel sheet: The thickness of galvanized steel sheet is generally 0.5mm to 1.5mm, and the length and width are the same as ordinary thin steel sheets. The surface of galvanized steel plate has a protective layer, which can prevent corrosion, and generally does not need to be painted. The requirements for the steel plate are that the surface is smooth and clean, and the thickness of the galvanized layer should not be less than 0.02mm. It is mostly used for moisture-proof air duct system, and the effect is better.

2. Stainless steel plate

Stainless steel plate has high plasticity, toughness and mechanical strength, corrosion resistance, is a kind of stainless alloy steel. Its main element, chromium, has high chemical stability, forms a passivation film on the surface, protects the steel plate from oxidation, and increases its corrosion resistance. However, stainless steel is easy to bend during cold working, and it will cause internal stress and uneven deformation when hammered, thereby reducing its toughness, increasing its strength, and becoming brittle and hard; after heating to 450-850 ° C, and then slowly cooling, the steel changes. damaged, hardened, cracked. Stainless steel is commonly used in corrosion-resistant air duct systems in the chemical industry because of its smooth surface, not easy to corrode and acid-resistant.

3. Aluminum plate (aluminum plate includes pure aluminum and alloy aluminum)

Alloy aluminum plates have high mechanical strength and poor corrosion resistance. Most of the aluminum plates used in ventilation projects are pure aluminum and annealed alloy aluminum plates.

Aluminum plate has beautiful color, low density, good plasticity, strong acid resistance, and good chemical corrosion resistance, but it is easily corroded by hydrochloric acid and alkali. Because the aluminum plate is soft and does not cause sparks in collision, it is mostly used as a ventilation duct with explosion-proof requirements.

4. Plastic composite steel plate

A layer of plastic film is pasted or sprayed on the ordinary steel plate, that is, the plastic composite steel plate. Its characteristics are corrosion resistance, and the processing performance of bending, bite, drilling, etc. is also good. Its specifications are 450mm×1800mm, 500mm×2000mm, 1000mm×2000mm and so on. Plastic composite steel plates are often used in air cleaning systems and ventilation and air conditioning systems with temperatures ranging from -10°C to +70°C.

5. PVC plastic sheet

PVC plastic sheet has good corrosion resistance and generally does not react chemically with acids, alkalis and salts, but it is unstable under the action of concentrated nitric acid, oleum and aromatic hydrocarbons. This kind of sheet has high strength, good elasticity, and poor thermal stability. The strength decreases at high temperature, and it becomes brittle and easy to crack at low temperature. A little pressure can make it bond.

The longitudinal and transverse properties of the sheet are different, and there is residual stress inside. When making air ducts and components, heating and cooling treatments are required; generally, the longitudinal and transverse shrinkage rates are 3% to 4% and 1.5% to 2.0%. In ventilation and air-conditioning engineering, it is mostly used for conveying corrosive gases such as acid, alkali, salt and other corrosive gas pipelines and components, and also used in clean systems.

6. Insulation material aluminum foil composite board

This material is a popular board in recent years. The structure consists of two layers of aluminum foil on the surface and the bottom, sandwiching a layer of insulation material in the middle, so it is also called a sandwich board. The material of the insulation layer is generally phenolic, PU and so on. Phenolic insulation board has the following characteristics:

a, high flame retardant, low smoke. The oxygen index can reach 56%, and the smoke density is less than 5. It does not burn at 1200 °C, and only carbonizes without dripping in case of fire.

b. Good insulation and low thermal conductivity. Phenolic foam material is composed of "closed small air bubbles", which can well block the thermal convection phenomenon formed by temperature. Its thermal conductivity is 0.02～0.03w/mk, which can save energy.

c. Stable weather resistance and high heat resistance. The use temperature of phenolic thermal insulation foam material is -60 ℃ ~ 150 ℃, dimensionally stable, non-absorbent, anti-aging, long service life.

d. Fluorine-free foaming, non-toxic and tasteless, is a green and environmentally friendly building material. The foaming process does not use chlorofluorocarbons, the ratio is reasonable, the reaction is complete, the formed compound has no residual poison, no odor, acid and alkali resistance, and has good resistance to acid and alkali.

Our professional phenolic air duct cutting machine can cut the material quickly and efficiently, and the cutting is precise and neat. If necessary, please contact us for details.