摘要 |
A process for producing a foamed material web, for example polystyrene, of constant density and thickness is disclosed as well as a tandem extruder system which is suitable for carrying out the process and has a corresponding control system. This object is achieved by a monitored feeding of the first extruder with a constant amount by weight of blowing agent and material, by a control of the screw speed of the first extruder dependent on the state of filling of its feed hopper and by monitoring and keeping constant the screw speed of the second extruder. |