Method using hot air circulation tunnel furnace, the furnace temperature uniformity, fast heat, air circulation and heating points are two kinds of far infrared heating, energy saving, (large tunnel furnace also can use diesel fuel or liquefied gas burner stove) has been widely applied metal products and plastic products in the dehydration drying, paint drying, wood furniture, metal metal, electroplating, electronics, printing, plastics, food industry, baking, drying and heat treatment. PVC conveyor belt by way of generally low temperature, Teflon mesh belt, high temperature stainless steel mesh belt, chain plate or galvanized chrome rollers. In accordance with the specific system to do according to customer requirements and design specifications