Steel ventilation ducts have galvanized steel duct, stainless steel duct and common duct three. A, galvanized steel duct can be used in various ventilation and air conditioning systems; B, stainless steel duct is mainly used for corrosive gases or significant ventilation system; C, ordinary steel duct is mainly used for air defense projects in the filter poison the system; Duct thickness is determined with the design department; duct flange specifications and galvanized steel duct flanges of the same specifications. Design tasks ventilation ducts, galvanized duct board, is to organize a reasonable air flow, to ensure the effect of the premise, the production of galvanized steel duct, so that the project initial investment and operation and maintenance costs of the province. Therefore, the ventilation duct design is reasonable, directly affect the entire ventilation, air-conditioning engineering construction and use of technical and economic results. Thus, the design of ventilation ducts and consider a variety of issues important enough. Wholesale galvanized sheet duct, Yanda air conditioning (certified), galvanized sheet duct provided by the Wu County Yanda air-conditioning plant. Wu County Yanda air-conditioning plant (www.wcydkt.com) (www.wcydkt.com) Shandong Dezhou, heat, refrigeration and air conditioning equipment leader, over the years, the company is implementing the scientific management, innovation and development, honesty and trustworthiness policy, and satisfy customer needs. In Yanda air conditioning leadership with the staff warmly welcome all inquiries negotiations to create Yanda air conditioning better future.