The barrel structure of the twin-screw pelletizer is the same as the barrel structure of the single-screw pelletizer, also divided into integral barrel and segmented combination barrel.
 
In the twin-screw pelletizing machine, the meshing anisotropic twin-screw pelletizing machine and conical twin-screw pelletizing machine generally use the integral barrel; only a few large pelletizing machine using the segmented combination barrel, in order to facilitate machining and save some of the more expensive alloy steel. Most of the meshed co-rotating twin-screw pelletizers use segmented barrels. Segmented barrels are divided into equal length sections, some with a feeding port, some with an exhaust port, and some with an additive port, and then the sections are connected with screws to form a twin-screw combination barrel.