PROCEDE DE PREPARATION DE MELANGES DE CHLORURES DE POLYVINYLE DANS UN MELANGEUR A CHAUD ET DISPOSITIF POUR LA MISE EN PRATIQUE DU PROCEDE

摘要

1517330 Mixing apparatus THYSSEN INDUSTRIE AG 28 Nov 1975 [29 Nov 1974] 49000/75 Heading BIC [Also in Division C3] An apparatus suitable for processing polyvinyl chloride mixtures comprises a heating mixer constructed as an upright cylindrical or double walled container closable by a cover and provided with a closable outlet, said cover having an air outlet aperture to which a suction pump is connected with interspersion of one or more dust separators, said container having mixing members arranged at its base and drivable at peripheral speeds of up to 40m/sec by means of a driving shaft which is passed through the base of the container and which cooperates with a seal assembly as illustrated in Fig. 2 comprising a plurality of superimposed lip seals, the top seal 20 of said assembly having its sealing lip pointing towards the interior of the container and a free annular space 21 located beneath this lip seal being connected by a connecting pipe and an adjustable throttle to the atmosphere, a free annular space 19 formed between the driving shaft and the sealing lip, which lip lifts slightly from the driving shaft in the case of negative pressure in the container, serving as an air inlet aperture.