◎ The Zhaohe spiral duct system is composed of a series of spiral straight pipes and pipe fittings made by stamping, seam welding or hand-made, which are quickly plugged in or flanged together, ensuring stable quality.
◎ Air duct systems are widely used in fields such as ships, Marine engineering, construction, fresh air, cruise ships, paper making, and fine chemicals.
◎ Equipped with international imported production lines, including Swiss spiral pipe machines, German TOX forming machines, Italian flanging equipment and South Korean fully automatic TDF air duct systems.
◎ Connection method： 1》Flange connection 2》Plug in the link.
◎ Material adoption： 1） Galvanized sheet: Double-sided galvanized, weight 120g-275g/㎡, sheet thickness 0.5mm-1.5mm，
                                               2）Stainless steel: SUS304, SUS304L, SUS316, SUS316L, plate thickness 0.5mm-1.0mm.

◆ The core product, the spiral duct system, far exceeds the national standards.
◆ The overall quality meets the European DW144 standard.
◆ The sealing performance has passed the CLASS D certification of the EU DW143 standard (the highest level in the industry).
◆ Pipe fittings are formed by stamping, with standardized and large-scale production. The dimensions are precise, the appearance is beautiful, the wind resistance is extremely small, and the sealing effect is excellent.
◆ The pipe fittings produced by the seam welding process have good sealing performance, do not damage the zinc layer, and the weld seams are neat, fine and beautiful.
◆ The "F" type EPDM sealing rubber ring is fixed with rolled edges. It does not slide or fall off during installation. The rubber ring has a good sealing effect and a long service life.
◆ It is convenient, simple and efficient to install, which can greatly save installation costs.