The electric steam mixing pre-foaming machine operates intermittently, and the control system adopts the most advanced PLC technology to evenly prefoam the beads. It consists of an automatic quantitative feeding system, a foaming machine pressurized foaming barrel, a computer control system, a discharge system, and a fluidized buffer bed. The electric steam pre-foaming can be started with one button and operated in a foolproof manner. Automatic feeding, foolproof operation, unmanned.