VENTED STUFFING DEVICE

PURPOSE:To reduce the deflection of shafts and consequently the leakage of sealing liquid and prevent the sealing properties of the device concerned due to the intrusion of polymer and the like from deteriorating by a method wherein collar-like gas barrier discs, labyrinth packagings, two mechanical seals, which are provided so as to be axially shifted to each other, and bearings, which support each mechanical seal in front and in rear, are provided.. CONSTITUTION:On respective shaftings 31b and 32b, gas barrier discs 33 and 34, labyrinth packings 35 and 36 and mechanical seals 37 and 38 are mounted. Screws 31 and 32 are supported by bearings 39 and 40 at two positions before and after the mechanical seals 37 and 38. The gas barrier discs 33 and 34 are collars in shape and make it hard for gas and polymer to enter the mechanical seals 37 and 38 and the labyrinth packings 35 and 36. In the labyrinth packings 35 and 36, water jackets for introducing cooling water are respectively provided on their outside surface and labyrinth grooves 43 and 44, the directions of rota tion of which are opposite to those of the screws, are provided on their inner surfaces so as to liquefy gasified solvent by cooling and, at the same time, to push back polymer by means of the labyrinth grooves 43 and 44.