The ventilation duct is an accessory to the building and few people study it. With the increase of the function of the spiral duct, the ventilation duct has not only the ventilation strength requirement, but also the functions of fire prevention, energy saving, environmental protection and easy cleaning. The use of ventilation ducts in China began in the 1940s. In the textile industry, in order to improve the quality of the spinning fabric, the pipeline to maintain the set temperature and humidity, and to deliver the specific temperature and temperature air is called the duct. At the earliest time, the duct was made of wood and then changed to iron.

In the 1980s, glass fiber reinforced polyester ducts appeared. The glass fiber polyester air duct is an organic material, which is resistant to water and gas corrosion and does not rust. It solves the defects that the galvanized iron duct is easy to rust and has a short service life, and is widely used in textile factories.

In the past ten years, in the general air-conditioning, glass fiber ducts, glass fiber reinforced plastic ducts and some imported composite ducts have been applied. It should be said that the appearance of composite ducts is an improvement in the ventilation duct industry. Of course, the form, nature and processing techniques of these materials are not suitable for the requirements of purification engineering. Therefore, there is no earthquake in the purification project, but in any case, the appearance of composite materials is an improvement in the wind pipe industry, and it is a kind of earthquake. The composite material is a trend in the world, and it can be said that it is industrial. The inevitable progress!

In the traditional duct construction, the insulation process is the hardest and most annoying, so the quality of the insulation is not guaranteed, because it is directly affected by the mood, responsibility and technical proficiency of the workers. The ventilating surface of the typhoon tube is bonded to the insulation layer at a time, so that the pipe does not need to be insulated after it is made. This easily solves the above-mentioned heat preservation problem, and, because of the removal of the heat preservation process, a large amount of man-hours are saved, thereby greatly reducing the labor cost in the pipe cost.

The traditional steel pipe is formed by biting, and the steel pipe flange is riveted at both ends of the pipe section. The leakage of the pipe generally occurs in these three parts - the intersection line - the joint of the steel plate and the flange, and the joint of the flange and the flange. . These joints of the composite duct are much better than the ducts of the steel plate. Of course, the airtightness is much better, which is mainly due to the complete change of the processing technology. The bridging of the composite duct pipe is mainly based on bonding, the joint strip is used instead of the bite slit, and the contact surface of the material in the joint strip is wider, and the joint is flexible, and the contact of the material in the seam of the steel sheet bite The surface is narrower and relatively rigid, so the degree of airtightness can be imagined.