Hot melts after melting with inert gas or air into the metering pump at the same time mixed, output to the glue gun. The external circulation part of the glue gun flows back to the melting cylinder and re-enters the gear pump. Foaming rate through nitrogen or air conditioning, the use of special foam foam foam efficiency of up to 50%, to save plastic 35% -45%. The flexibility of the glue is better, not broken, the product is better sealed, similar to sponge. The host computer is driven by servo. The machine is mainly used in honeycomb filter, household air purifier, household refrigerator, air conditioner, electronics, automobile and other industries foam sealing.