Apparatus for producing a material web

Abstract

An apparatus for producing a fibrous web, in particular a tissue, paper or cardboard web, has a forming section and a dryer section, whereby the dryer section includes a pressure nip formed by a suction roll and a press roll, a drying cylinder and a transfer pressure nip which is positioned downstream from the pressure nip for transferring the fibrous web to the drying cylinder, whereby the fibrous web together with a clothing wraps around the suction roll in a wraparound region in such a way that the clothing is positioned between the suction roll and the fibrous web.

What is claimed is: 
     
         1 . An apparatus for producing a web of fibrous material, said apparatus comprising:
 a forming section;   a clothing;   a dryer section including a suction roll, a press roll, a drying cylinder, a transfer pressure nip, and a heating device, said suction roll and said press roll forming a pressure nip, said transfer pressure nip being positioned downstream from said pressure nip and being configured for transferring the web to said drying cylinder, the web together with said clothing wrapping around said suction roll in a wraparound region in such a way that said clothing is positioned between said suction roll and the web, said wraparound region being located upstream of said pressure nip, said heating device being assigned directly to the web in said wraparound region.   
     
     
         2 . The apparatus according to  claim 1 , wherein the web is one of a tissue web, a paper web, and a cardboard web. 
     
     
         3 . The apparatus according to  claim 1 , wherein said clothing is a textured fabric. 
     
     
         4 . The apparatus according to  claim 1 , further including an inside felt, said suction roll being partially wrapped by said inside felt which is positioned between said clothing and said suction roll. 
     
     
         5 . The apparatus according to  claim 4 , wherein said inside felt is routed through said transfer pressure nip. 
     
     
         6 . The apparatus according to  claim 4 , wherein said inside felt is more compressible than said clothing. 
     
     
         7 . The apparatus according to  claim 1 , wherein said clothing is a water-absorbing felt. 
     
     
         8 . The apparatus according to  claim 1 , wherein said heating device is one of a steam blow box and a hot air blower hood. 
     
     
         9 . The apparatus according to  claim 1 , wherein the apparatus includes a region of said wraparound region and a region of said pressure nip, said suction roll including a suction box at least one of (a) in said region of said wraparound region, (b) in said region of said pressure nip, and (c) after said pressure nip, providing at least one suction zone. 
     
     
         10 . The apparatus according to  claim 1 , wherein the apparatus includes a region of said wraparound region and a region of said pressure nip, said suction roll including a suction box at least one of (a) in said region of said wraparound region, (b) in said region of said pressure nip, and (c) after said pressure nip, providing a plurality of suction zones. 
     
     
         11 . The apparatus according to  claim 1 , wherein a distance between said forming section and said dryer section is greater than a transfer distance created by a distance between said pressure nip and said transfer pressure nip. 
     
     
         12 . The apparatus according to  claim 11 , wherein said transfer distance is shorter than 3 meters. 
     
     
         13 . The apparatus according to  claim 11 , wherein said transfer distance is shorter than 2 meters. 
     
     
         14 . The apparatus according to  claim 11 , wherein said transfer distance is shorter than 1.5 meters. 
     
     
         15 . The apparatus according to  claim 1 , further including an outside felt, said outside felt being partially wrapped around said press roll. 
     
     
         16 . The apparatus according to  claim 1 , wherein said clothing and the web are routed through said transfer pressure nip. 
     
     
         17 . The apparatus according to  claim 1 , wherein said wraparound region extends in an angular range of 45° to 120°. 
     
     
         18 . The apparatus according to  claim 1 , wherein said wraparound region extends in an angular range of between 80° and 100°.