It is provided a method for preparing a thermosetting material, in particular a elastomer, for injection molding, the method comprising: flowing the thermosetting material through a conduit (111, 113, 115, 123, 311), the conduit having a variable cross-sectional area in order to increase an average temperature of the thermosetting material; controlling a flow rate of the thermosetting material flowing through the conduit based on a parameter indicative of a heating characteristics of the thermosetting material due to a stretching the thermosetting material; and ejecting the prepared thermosetting material form the conduit. Further another method and corresponding apparatuses are provided.