Sealing elements in a twin-wire paper machine

Abstract

Twin-wire presses are disclosed for dewatering fiber suspensions comprising endless upper and lower wires defining a dewatering space, upper and lower wire guides for guiding the wires obliquely towards the inlet end of the dewatering space, and upper and lower wedge-shaped seals extending from an inlet box towards the dewatering space inlet to create a seal in the tapering space between the wires and the fiber suspension entering the dewatering space. The inner surfaces of the wedge-shaped seals define a passage for the fiber suspension and the outer surfaces extend at an acute angle towards the inner surfaces so that at least part of the seals are sealed against the wires and the distance between the inner surfaces of the seals is substantially equal to the distance between the wires at the dewatering space inlet.

1 - 10 . (canceled) 
   
   
       11 . A twin-wire press for dewatering a fiber suspension comprising an endless lower wire and an endless upper wire defining an elongated dewatering space therebetween having an inlet end and an outlet end for dewatering said fiber suspension during simultaneous displacement of said endless upper and lower wires, an inlet box for supplying said fiber suspension to said inlet end of said elongated dewatering space, upper and lower perforated dewatering elements disposed against the sides of said endless upper and lower wires outside of said elongated dewatering space, an upper outlet box for collection of filtrate flowing from said elongated dewatering space through said upper wire and said upper perforated dewatering element, a lower outlet box for collection of filtrate flowing from said elongated dewatering space through said lower wire and said lower perforated dewatering element, an upper wire guiding member arranged to guide said endless upper wire obliquely downwardly towards said inlet end of said elongated dewatering space, a lower wire guiding member arranged to guide said endless lower wire obliquely upwardly towards said inlet end of said elongated dewatering space, whereby a tapering space is formed between said upper and lower wire guiding members, and upper and lower wedge-shaped sealing members extending from said inlet box towards said inlet end of said elongated dewatering space for creating a seal in said tapering space between said endless upper and lower wires and said fiber suspension entering said elongated dewatering space, said upper and lower wedge-shaped sealing members defining a passage therebetween for said fiber suspension flowing to said elongated dewatering space from said inlet box, each of said wedge-shaped upper and lower sealing elements including an inner surface defining part of said passage for said fiber suspension and an outer surface extending at an acute angle towards said inner surface, at least part of said wedge-shaped upper and lower sealing elements sealingly disposed against its respective upper and lower wire, the distance between said inner surfaces of said upper and lower wedge-shaped sealing elements forming said passage for said fiber suspension being substantially equal to the distance between said upper and lower wires at the inlet end of said elongated dewatering space. 
   
   
       12 . The twin-wire press of  claim 11  wherein said at least part of each of said upper and lower wedge-shaped sealing elements is sealingly disposed against its respective upper and lower wire only at the location of said respective upper and lower wire guiding member corresponding thereto. 
   
   
       13 . The twin-wire press of  claim 11  wherein said inner and outer surfaces of each of said upper and lower wedge-shaped sealing elements tapers into a narrow, tongue-shaped portion towards a free end of said respective upper and lower wedge-shaped sealing elements in abutment against the inner surfaces of said upper and lower wires, respectively. 
   
   
       14 . The twin-wire press of  claim 11  wherein each of said upper and lower wedge-shaped sealing elements and said corresponding upper and lower wire guiding members includes adjacent oblique portions abutting against each other with said upper and lower endless wires therebetween. 
   
   
       15 . The twin-wire press of  claim 11  wherein said upper and lower wedge-shaped sealing elements comprise a polymer. 
   
   
       16 . The twin-wire press of  claim 11  wherein each of said upper and lower wedge-shaped sealing elements is horizontally adjustable against each of said respective upper and lower wire guiding members in the longitudinal direction of said twin-wire press. 
   
   
       17 . The twin-wire press of  claim 11  wherein said upper and lower wire guiding members are vertically adjustable against said upper and lower wedge-shaped sealing elements. 
   
   
       18 . The twin-wire press of  claim 11  wherein said upper and lower wire guiding members include wear element portions disposed against said upper and lower endless wires respectively. 
   
   
       19 . The twin-wire press of  claim 11  wherein said upper and lower wire guiding members are integrally attached to said upper and lower perforated dewatering elements. 
   
   
       20 . The twin-wire press of  claim 11  wherein said upper and lower wire guiding members are integral with said upper and lower perforated dewatering elements, respectively.