It is presented a concept for simple processing related rheological characterisation of rubber. A modified injection-moulding machine was equipped with a slit die, a suitable and powerful data acquisition system and a special mixing device. The energy-balance was carried out, The examined EPDM-compound showed a strong tendency for wall slipping. This wall slipping velocity was calculated as a function of the wall stress and the temperature. The shear viscosity was determined from the volumetric rate caused by shear flow.