Abstract: Pulper used in the paper industry that processes pulp which pulper comprises a pulper container (19), a punched plate screen (15) installed to the mentioned container, a binnacle (8) out of the lower part (3) of the container for the mass that has penetrated the punched plate screen (15) and a rotating mixing rotor located in the container (19) and equipped with wings (1); (5) the purpose of which mixing rotor is to defibrate paper and mix the mass in the container (19) and that the mixing rotor further comprises a cylinder part (20) directed downwards towards the punched plate screen (15) and that rotates along the mentioned rotor to which cylinder part wings (2) that clean the punched plate screen (15) are attached and which cylinder part (20) is located between the mixing rotor and the punched plate screen (15).