Device for continuously dewatering a fiber web

A device for continuous dewatering of a web of fiber material in a paper making machine, or the like, comprising:

• a porous belt for water to pass through, and horizontally oriented guide rolls and the like for guiding and moving the belt for movement longitudinally of the belt;
• the belt having one surface adapted to receive thereon a fiber web to be dewatered, and the belt also having an opposite other surface;
• the guide rolls and the like define such a path for the belt and cause the belt to move at such speed that at least part of the water which has been removed from the fiber web penetrates through the belt and is thrown off the opposite surface of the belt;
• a container placed near the belt opposite surface for receiving water thrown off the belt opposite surface;
• the container being divided into two separate water containing chambers, and each chamber extending across the width of the belt;
• each chamber having a respective water exit therefrom;
• a guide wall above the area from which the water is thrown, said guide wall being positioned to be struck by the water thrown off the belt and to direct the thrown off water into the container;
• the guide wall being shaped and positioned to direct the more dense jets of water into a first one of the chambers of the container;
• the said belt being in the form of an endless loop;
• said web being received against the one surface which is the outside surface of the loop, and the container being positioned at the inside of the loop of the belt and a second belt for cooperating with the first-mentioned belt, said second belt being positioned and adapted to press a web between the first and second belts in the vicinity of the container;
• the exit from one chamber being at one lateral side of the container and the exit from the other chamber being at the opposite lateral side of the container;
• the said container being shaped so that the respective inside width of each chamber, measured along the path of the belt, increases laterally along the container in the direction toward the respective exit from that chamber;
• one of the guide rolls for the first belt comprising a dewatering roll which is located toward the lower region of the path of the first belt;
• the first belt passes at least predominantly around the bottom side of the dewatering roll;
• the dewatering roll including an external shell with recesses defined in the shell which receive water from the first belt in the region where the first belt is wrapped around the dewatering roll, and beyond where the belt is guided off the dewatering roll, the said dewatering roll throwing off water.

A device for continuous dewatering of a web of fiber material in a paper making machine, comprising:

• (a) a lower endless wire belt 21 forming a lower belt loop and a substantially horizontal pre-dewatering path 23;
• an upper endless wire belt 22 forming an upper belt loop;
• horizontally oriented guide rolls for guiding and moving the upper wire belt around said guide rolls;
• the upper wire belt cooperating with the lower wire belt;
• the wire belts forming a twin-belt zone;
• the said fiber web to be dewatered being guided between the wire belts;
• (b) one of the guide rolls 25 for the upper wire belt 22 being a dewatering roll located inside said upper belt loop and conducting the upper wire from above downwards on to the substantially horizontal pre-dewatering path of the lower wire belt and forming an initial region of the twin-belt-zone wherein the wire belts being wrapped around the dewatering roll up to a point of departure;
• (c) the point of departure of the wire belts from the dewatering roll lying in the lower ascendant quadrant of the roll shell;
• (d) the wire belts wrapping, directly behind the dewatering roll as seen in the direction of travel together with the fiber web therebetween, around a support roll arranged within the lower belt loop, with the wire belts travelling downward from the support roll;
• (e) the dewatering roll including an external shell with recesses defined in the shell, said recesses receiving water from the upper wire belt in said initial region of the twin wire zone, the said dewatering roll, throwing off said water out of said recesses from below upwards into the interior of the upper belt loop;
• (f) a container 36 placed inside said upper belt loop for receiving water thrown off the upper wire belt and off said dewatering roll;
• said container being arranged behind the support roll 26 as seen in the direction of travel of the wire belts;
• (g) a guide wall 40 being placed inside said upper belt loop and being positioned to be struck by the water thrown off the first wire belt and off said dewatering roll and directing the thrown off water into the container;
• said guide wall 40 being at the same time a covering wall of the container 36 and having a front edge 41 which is arranged within the wedge-shaped nip present between the dewatering roll and said wire belts (near said point of departure);
• (i.) the upper region of the dewatering roll 25 being covered by an additional guide wall 37 for water which has been slung off;
• an exit groove 38 being connected to the additional guide wall;
• the additional guide wall 37 being connected to said front edge 41 of the first-mentioned guide wall 40.