The kind of pu conposite plate has characters as follows: 1,fine and smooth abscess; 2,well-distributed densitty; 3,guaranteed intension and heat insulation; 4,not lenght limit (≥2meters); Operating Environment 1,Working Temperature:-50—+80°C 2,Humidity:0—100% 3,Working Pressure:-2000—+2000Pa 4,Wind speed:less than 12m/s Key performance 1,Average frictional resistance coefficient of HuaYu Duct λ=0.0142 2,When the static pressure in the pipe is =2000Pa,the air inleakage rate is 0.When the pressure difference inside and outside the pipe is 4000Pa(positive or negative),visual test whether there is distortion or damage in the pipe . 3,In standard test condintion ,after operating for morre than five hours stably,there is no dewing outside the pipe. Features 1,Easy to manufacture; 2,Quick to install; 3,Pretty and durable; 4,Environmental friendly and energy saving . The kind of pu conposite plate has characters as follows: 1,fine and smooth abscess; 2,well-distributed densitty; 3,guaranteed intension and heat insulation; 4,not lenght limit (≥2meters); Operating Environment 1,Working Temperature:-50—+80°C 2,Humidity:0—100% 3,Working Pressure:-2000—+2000Pa 4,Wind speed:less than 12m/s Key performance 1,Average frictional resistance coefficient of HuaYu Duct λ=0.0142 2,When the static pressure in the pipe is =2000Pa,the air inleakage rate is 0.When the pressure difference inside and outside the pipe is 4000Pa(positive or negative),visual test whether there is distortion or damage in the pipe . 3,In standard test condintion ,after operating for morre than five hours stably,there is no dewing outside the pipe. Features 1,Easy to manufacture; 2,Quick to install; 3,Pretty and durable; 4,Environmental friendly and energy saving .