Shearing part

A shearing part for a plasticising screw, with at least one inlet channel, which has an open inlet channel start situated at the upstream end of the shearing part, and a closed inlet channel end situated at the downstream end of the shearing part, and with at least one outlet channel, which has an open outlet channel end situated at the downstream end of the shearing part, and a closed outlet channel start situated at the upstream end of the shearing part, wherein the at least one inlet channel and the at least one outlet channel run helically around the longitudinal axis of the shearing part or parallel to the longitudinal axis of the shearing part, wherein

• the inlet channel and the outlet channel are arranged lying directly adjacent to one another and contiguous to one another, wherein the inlet channel continues directly into the outlet channel and the inlet channel and the outlet channel are fluidically connected here directly with one another, in such a way that melt flowing into the inlet channel can flow over directly from the inlet channel into the outlet channel, wherein a flow direction is produced which lies substantially transversely to the longitudinal axis of the shearing part, that the inlet channel has a depth at which a shearing action on the melt flowing through the inlet channel is avoided, and that the outlet channel is configured as shearing surface, in such a way that a shearing action is present on the melt flowing through the outlet channel,
• wherein, at a transition between the inlet channel and the outlet channel, a rounding is provided comprising a rounded channel boundary that extends in a direction substantially transversely to the longitudinal axis of the shearing part.