Measuring arrangement and method for determining properties of a material to be extruded while a screw-extrusion process is being carried out

A measuring arrangement for determining properties of a material to be extruded while an extrusion process is being carried out in an extruder, comprising:

• at least one extruder screw rotatably mounted in a tubular guide in a barrel, said at least one extruder screw is connected to a rotary drive and material to be extruded can be fed to the tubular guide at one end and can be removed as finish-extruded material at an oppositely arranged discharge, and
• multiple first sound transducers arranged at measuring positions at predeterminable defined intervals on a wall of the tubular guide along the longitudinal axis of the extruder screw, said multiple first sound transducers adapted for the detection of sound waves that are at least generated as extrusion process noise by the extrusion process or are emitted by a second sound transducer, arranged at one end of the tubular guide, in the direction of a longitudinal axis of the at least one extruder screw and into the material to be extruded that is conveyed through a mixing chamber present in the tubular guide.