The number of wrapping belt in the packaging industry is very large, the market in Guangdong, China, there are nearly a thousand production lines, basically all with scrap production, impurities and change the net is extremely frequent, and are manually stopped to change the net, resulting in a large number of back to material, waste, easy to form a vicious circle. The strength of the scrap is originally low, and then recycling energy consumption, waste of labor, and then the quality of the product will also be reduced. It is a new multi-station structure with preheating and exhausting mechani