Gearbox assembly for a twin-screw extruder, treatment installation for material treatment comprising a gearbox assembly of this type, and method for the startup of a treatment installation comprising a gearbox assembly of this type

A method for the startup of a treatment installation for material treatment, the method comprising the following steps:

• providing a treatment installation for material treatment, the treatment installation comprising
• a gearbox assembly comprising
• a first speed change gearbox for adjusting a screw shaft speed of two screw shafts of a twin-screw extruder,
• a distribution gearbox with two distribution gearbox output shafts allowing the screw shafts of the twin-screw extruder to be coupled thereto,
• a speed reduction gearbox that couples the first speed change gearbox to the distribution gearbox, the speed reduction gearbox having precisely one speed reduction gearbox input shaft, with a speed change gearbox output shaft of the speed change gearbox being detachably connected to the speed reduction gearbox input shaft in such a way that the speed reduction gearbox is separable from the first speed change gearbox,
• a drive motor coupled to the first speed change gearbox, and
• a twin-screw extruder the screw shafts of which are coupled to the distribution gearbox,
• separating the first speed change gearbox from the drive motor and the speed reduction gearbox,
• replacing the first speed change gearbox by a second speed change gearbox,
• coupling the second speed change gearbox to the drive motor and the speed reduction gearbox, and
• starting up the twin-screw extruder by means of the drive motor.