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With the passage of time, people's requirements for ventilation duct cleaning and the saving of equipment and materials are also gradually improving; With the progress of technology, people's requirements for the quality of HVAC engineering have also increased. Many existing stainless steel air ducts and spiral round air ducts are used to meet the functional requirements of ventilation, air conditioning and dust removal transportation.

這就需要在現有技術上不斷進步，在設備規劃、開發和制造方面采用更節約材料、更健康和更可持續的發展戰略。目前用于空調通風工程的金屬風道主要有圓形風道和不銹鋼風道。圓形風管強度高，耗材少，但加工工藝較亂，占用空間大;不銹鋼風道，便于布置和加工，應用廣泛。也有機械生產的，螺旋形由鋼帶繞制而成，有圓形、長方形，為了節省空間，許多不銹鋼風管用平圓制成。

This requires continuous progress in existing technology and the adoption of more material-saving, healthier and more sustainable development strategies in equipment planning, development and manufacturing. At present, the metal air ducts used in air conditioning and ventilation projects mainly include circular air ducts and stainless steel air ducts. The circular air duct has high strength and less consumables, but the processing technology is messy and takes up a lot of space; Stainless steel air duct, easy to arrange and process, is widely used. There are also mechanical ones. The spiral shape is made of steel strip. There are circular and rectangular shapes. In order to save space, many stainless steel air ducts are made of flat circles.

通風管道的制造和加工，特別是對于一些小型企業，手工車間式企業，這樣的企業不會長久生存下去。因為我們認為，一個企業的發展離不開其企業文化和戰略的發展。雖然主風道仍為鐵板，但由于環保、使用壽命、防潮、隔音、承重等原因，在施工和保護方面存在很多缺陷。這導致了市場對新產品的需求來改善這一問題。新型不銹鋼風管的出現正好適應了商場的需求。經過多次工程應用和實踐，逐漸被投資者所接受。

The manufacturing and processing of ventilation pipes, especially for some small enterprises, manual workshop enterprises, such enterprises will not survive for a long time. Because we believe that the development of an enterprise is inseparable from the development of its corporate culture and brand strategy. Although the main air duct is still made of iron plate, there are many defects in construction and protection due to environmental protection, service life, moisture-proof, sound insulation, load-bearing and other reasons. This leads to the market demand for new products to improve this problem. The emergence of new stainless steel air ducts just meets the needs of shopping malls. After many engineering applications and practices, it is gradually accepted by investors.

商場風管一般分為三類:鍍鋅不銹鋼風管、不銹鋼不銹鋼風管和復合不銹鋼風管。同時，不銹鋼風管質量好，適用性強，但價格昂貴。目前商場中使用較為廣泛的不銹鋼風管是鍍鋅鋼板風管。鍍鋅不銹鋼風管基本上是不銹鋼風管的特點，但其價格卻比不銹鋼風管低三分之二甚至更低。復合不銹鋼風道一般用于外部環境比較一般，對風道要求不太高的地方。由于鐵片是簡單的，在各種環境中發生化學反應，導致腐蝕和生銹。然而，鋅在干燥的空氣中幾乎不會發生變化。在潮濕的空氣中，鋅的表面會形成良好的堿性碳酸鋅膜。不銹鋼風筒主要是在風筒的鐵片上鍍一層鋅，以保護鐵片。鍍鋅層經鈍化、染色或涂覆光保護劑后，其保護和裝飾性能均有明顯改善。

Air ducts in shopping malls are generally divided into three categories: galvanized stainless steel air ducts, stainless steel air ducts and composite stainless steel air ducts. At the same time, the stainless steel air duct has good quality and strong applicability, but it is expensive. At present, galvanized steel air ducts are widely used in shopping malls. Galvanized stainless steel air duct is basically the feature of stainless steel air duct, but its price is two-thirds lower or even lower than that of stainless steel air duct. Composite stainless steel air duct is generally used in places where the external environment is relatively general and the requirements for air duct are not too high. Because the iron sheet is simple, chemical reactions occur in various environments, resulting in corrosion and rust. However, zinc hardly changes in dry air. In humid air, a good alkaline zinc carbonate film will be formed on the surface of zinc. Stainless steel air duct is mainly coated with zinc on the iron sheet of the air duct to protect the iron sheet. After passivation, dyeing or coating with light protective agent, the protective and decorative properties of zinc coating are significantly improved.

通風管道耐久性差。氯化鎂和氧化鎂的摩爾比是有科學依據的。氯化鎂的含量應根據氧化鎂中活性鎂含量的測定來確定。然而，不合格產品的生產廠家不知道氧化鎂活性鎂含量的測定，更不用說合理的摩爾比值。只知道氧化鎂和鹽水，凝固成風管。風道余氯離子含量大，在濕空氣環境中容易返鹵水，軟化系數低，使用壽命短。

The durability of ventilation duct is poor. The molar ratio of magnesium chloride to magnesium oxide has scientific basis. The content of magnesium chloride should be determined according to the determination of active magnesium content in magnesium oxide. However, the manufacturers of unqualified products do not know the determination of magnesium oxide active magnesium content, let alone a reasonable molar ratio. Only magnesium oxide and salt water are known to solidify into air ducts. The residual chloride ion content in the air duct is large, and it is easy to return brine in the wet air environment, with low softening coefficient and short service life.