The basic requirements for the material and size of the ventilatory ducts
First, the ventilation pipe material
1 sheet metal:
Ordinary thin steel plate: good processing performance and structural strength, but easy to rust;
Galvanized steel sheet: the surface of galvanized, rust-proof effect, generally used to produce no acid mist in the humid environment;
Aluminum and aluminum alloy plate: processing performance,ventilatory ducts corrosion resistance, friction is not easy to produce sparks, commonly used in explosion-proof requirements of the ventilation system;
Stainless steel plate: with rust and acid resistance, commonly used in the production of cold, shabby air duct and chemical environment to be corrosion-resistant ventilation system;
Plastic composite steel plate: in the ordinary steel plate surface sprayed with a layer of 0.2-0.4mm thick plastic layer, commonly used in dustproof requirements of high air conditioning system and -10 degrees -70 degrees temperature corrosion resistance system duct;
2 non-metallic materials:
Unplasticized polyvinyl chloride plastic plate: suitable for the use of acidic corrosive ventilation system, with a smooth surface, easy production, etc., but not high temperature,ventilatory ducts not cold, only for 0-60 degrees Celsius air environment, under the action of solar radiation Brittle
FRP: with light, high strength, non-combustible, corrosion-resistant, high temperature, anti-cold and other characteristics.
Second, the basic requirements of ventilation pipe size
Ventilation, air conditioning system of the duct, should adopt a round or long,ventilatory ducts short side ratio of not more than 4 rectangular cross-section, the maximum length, short side ratio should not exceed 10. Duct size, should be in accordance with the current national standard "ventilation and air conditioning construction quality acceptance norms" (GB 50243) in the provisions of the implementation of the metal pipe diameter should be outside diameter or outside long; non-metallic duct diameter Should be long inside or inside.