According to the different characteristics and packaging requirements of different products, online thermoforming packaging equipment is divided into two types: hard film stretching and soft film stretching. Dural stretching includes two types: modified atmosphere packaging and vacuum skin packaging, mainly used in the fields of snack food, fresh food, aquatic products, baked goods, medical equipment, hardware, pre packaged dishes, etc; Soft film stretching is mainly used in vacuum packaging and is mainly applied in industries such as frozen food and snack food.