With the passage of time, people's requirements for cleaning of ventilation pipes and saving of equipment and materials are gradually improved; with the progress of technology, people's requirements for the quality of HVAC engineering are also correspondingly improved. The existing stainless steel air duct and spiral air duct are widely used to meet the functional requirements of ventilation, air conditioning and dust removal.

　　这就要求在现有技术不断进步的同时，采用更多的节材、健康、可持续的发展战略进行设备的设计、开发和制造。目前，空调通风工程中金属风管的主要形式有:圆形风管、不锈钢风管。圆管强度消耗小，但加工工艺复杂，占用空间大。不锈钢风管易于布置，易于加工，所以使用比较普遍。也有机械制作的由钢带螺旋缠绕而成的系统，圆形、长方形，为了节省空间，大量的不锈钢风管做成扁平状。

　　This requires more material saving, healthy and sustainable development strategies to design, develop and manufacture the equipment while the existing technology is constantly improving. At present, the main forms of metal air duct in air conditioning and ventilation engineering are: round air duct and stainless steel air duct. The strength consumption of the pipe is small, but the processing technology is complex and takes up a lot of space. Stainless steel air duct is easy to arrange and process, so it is widely used. There are also mechanical systems made of spiral wound steel strips, circular and rectangular. In order to save space, a large number of stainless steel air ducts are made into flat shapes.

　　通风管道的生产加工，特别是对一些小型企业、手工工坊型企业来说，这样的企业生存不了多久。因为企业认为企业的发展离不开企业文化和战略。虽然目前占主导地位的仍是铁皮这种风管，但由于这些风管环保、寿命、防潮、隔音、承重等方面的原因，在施工和维护中存在许多缺陷。这导致了市场需要一款新产品来改善这一问题，新型不锈钢风管的出现，正好适应了市场的需求，通过大量的工程应用和实践，逐渐被投资开发商所接受。

　　The production and processing of ventilation pipes, especially for some small enterprises and manual workshop enterprises, such enterprises will not survive for long. Because enterprises think that the development of enterprises can not be separated from corporate culture and brand strategy. Although the iron sheet air duct is still dominant at present, there are many defects in construction and maintenance due to the environmental protection, service life, moisture-proof, sound insulation, load-bearing and other reasons of these air ducts. This leads to the market need for a new product to improve this problem, the emergence of new stainless steel air duct, just to meet the market demand, through a large number of engineering applications and practices, gradually accepted by the investment developers.

　　风管市场按材质一般分为三类:镀锌不锈钢风管、不锈钢风管和复合不锈钢风管。其中，不锈钢风管质量较好，适用性强，但价格较高。目前，市场上比较广泛的是镀锌不锈钢风管。镀锌不锈钢风管，基本上是不锈钢风管的特点，但价格相对只有不锈钢风管的三分之二甚至更低。复合不锈钢风管一般多用于外部环境比较常见，对风管要求不太高。由于铁板在各种环境中容易产生化学反应，引起腐蚀、生锈。另一方面，锌在干燥的空气中变化不大。在潮湿的空气中，锌表面会形成一层致密的碱性碳酸锌膜。不锈钢风管主要是在风管铁板上涂一层锌，以保护铁板。镀锌层经钝化、染色或涂上防护光剂后，可显著提高其防护性和装饰性。

　　The air duct market is generally divided into three categories by material: galvanized stainless steel air duct, stainless steel air duct and composite stainless steel air duct. Among them, the quality of stainless steel air duct is good, applicability is strong, but the price is high. At present, galvanized stainless steel air ducts are widely used in the market. Galvanized stainless steel air duct is basically the characteristics of stainless steel air duct, but the price is only two-thirds or even lower than that of stainless steel air duct. The composite stainless steel air duct is usually used in the external environment, so the requirement of air duct is not very high. Because the iron plate is easy to produce chemical reaction in various environments, causing corrosion and rust. Zinc, on the other hand, does not change much in dry air. In humid air, a dense alkaline zinc carbonate film is formed on the surface of zinc. The stainless steel air duct is mainly coated with a layer of zinc on the iron plate of the air duct to protect the iron plate. After passivation, dyeing or coating with protective light agent, the protective and decorative properties of zinc coating can be significantly improved.

　　通风管道耐久性差氯化镁与氧化镁克分子量比的依据是科学依据，是确定活性镁含量的氧化镁氯化镁的用量。但是，生产不合格产品的厂家不知道氧化镁活度的测定方法和合理的摩尔比值。只知道氧化镁加卤水，固化成管后。风管残余氯离子含量大，在潮湿空气环境中容易返卤，软化系数低，使用寿命短。

　　The basis of the ratio of MgCl 2 to MgO is scientific basis, which is to determine the amount of MgCl 2 with active MgO content. However, the manufacturers of unqualified products do not know the determination method of MgO activity and the reasonable molar ratio. Only magnesium oxide with brine, solidified into a tube. The residual chloride ion content of air duct is large, and it is easy to return brine in humid air environment, with low softening coefficient and short service life.