The meltblown process requires large amounts of hot air. Compressor output of compressed air through the dehumidifier filters and transported to the air heater, and then sent to the meltblown die head assembly. The air heater is a pressure vessel, and to resist the high temperature air oxidation, the material must be made of stainless steel. The air heater heating element stainless steel electric heating pipe. The heater cavity set up more Baffled extend the residence time of air in the heater cavity, in order to improve heat exchange efficiency. Appropriate to increase the number of heating pipes, air heater installed power, and can shorten the production line to drive the heating time. The meltblown process on the draft air heater temperature control precision are higher, and the draft air temperature required to stabilize within the range of ± 1 ° C.