The products are baked continuously on the assembly line to improve the production efficiency. The tunnel oven can be transmitted by Teflon or metal mesh belt, the heating tube is installed in the top duct (or both sides of the duct), the room temperature is adjustable from room temperature to 250℃, and the door curtain is sealed by silicone rubber. Adopting the new technology of far infrared heating which is promoted by the State Science and Technology Commission, the far infrared element can radiate far infrared rays of more than 2~15 microns after being heated, and when it is absorbed by the heated object, it can be directly transformed into heat energy, so as to get the effect of rapid drying, shorten the production cycle, save energy, improve product quality and so on, which is easy to use and saves energy!