Aerosol polyurethane foam (PU foam) is used for sealing plastic windows, doors or any gaps or cavities. This kinds of aerosol product require to put two kinds of material (MDI and PPG) into the aerosol can , and then capping immediately and meanwhile input two kinds of the propellant (DME AND LPG ) . and press the screw thread cap , and the last step is that vibrating the aerosol can , it is used to mixing the liquid material and propellant , the filling working condition require less than10 , furthermore ,before filling we should heating or warm the PPG .that can get better filling speed and filling accuracy , we suggest the manufacturer to set up the gas station (DME and LPG ) ,sometimes ,we should increase or keep the pressure on DME and LPG ,then the propellant will turn into the liquid state .because it is easy and better to supply to the inflating machine at this situation  .