Injection moulding is one of the most common methods to produce rubber parts. For rubber the curing time is the biggest part of the cycle time which is an important factor for the efficiency of the production due to machine and working hours. For the reduction of the curing time preheating of the material during the injection process is needed. The energy is brought into the rubber by shearing and heat conduction. In the experiments a heat-shear-mixing device is used. It was developed at the IKV Leoben. It is mounted on a mould that was used for the rheological characterization of rubber compounds. In the experiments the influence of the material, modifications of the mixing device, the barrel temperature and the injection speed were investigated. After this the properties of the produced parts were analyzed. The hardness, the compression set, the tensile strength and the elongation at break were tested to determine the possible reduction of the curing time in dependence of the desired properties. In the experiments it was proven that a significant reduction of curing time can be realized using this mixing device. Depending on the modification of the device relevant rises in the melt temperature were detected which lead to a cure time reduction up to 50%. But these values are strongly dependent of the rubber compound and the part's thickness. A direct constructive realization is not possible at the moment because of the material loss in the gate and the mixing device. After the experiments a simulation was made using the software Polyflow. The mixing device and another unheated, short and intense shear gap were modelled. The simulation showed that similar temperatures can be realized with both geometries, but the short gap showed higher losses in pressure.