Doctor blade arrangement and method in fibre processing

Abstract

Apparatus for removing fiber webs from fiber conveying supports are disclosed including a doctor beam, a doctor blade having a web contacting edge, a hose for fluids for applying a force between the doctor beam and the doctor blade when pressurized to move the web contacting edge towards the fiber conveying support, the fiber web having a basis weight over 1000 g/m 2 , the doctor blade and doctor beam being pivotably attached, and the hose arranged for applying the force at a distance form the pivotable attachment to move the web contacting edge by pivoting the doctor blade relative to the doctor beam.

1 . An arrangement for removal of a fiber web from a fiber conveying support, comprising:
 a doctor beam;   a doctor blade having a web contacting edge; and   a hose for fluids arranged for applying a force between said doctor beam and said doctor blade when being pressurized to move said web contacting edge towards said fiber conveying support;   said fiber web having a basis weight over 1000 g/m 2 ;   said doctor blade and said doctor beam being attached to each other by a pivotable attachment; and   said hose being arranged for applying said force at a distance from said pivotable attachment to move said web contacting edge by pivoting said doctor blade relative to said doctor beam.   
     
     
         2 . The arrangement according to  claim 1 , wherein said hose is provided in a recess in said doctor blade and arranged to actuate on said doctor beam. 
     
     
         3 . The arrangement according to  claim 1 , wherein said hose is provided in a recess in said doctor beam and arranged to actuate on said doctor blade. 
     
     
         4 . The arrangement according to  claim 1 , wherein said hose is applying said force on said doctor blade at a side opposite to said web contacting edge relative to said pivotable attachment. 
     
     
         5 . The arrangement according to  claim 1 , wherein said hose is a gas hose. 
     
     
         6 . The arrangement according to  claim 1 , wherein said pivotable attachment is provided by clamping said doctor blade between a main portion of said doctor beam and a clamping plate, in turn mechanically attached to said main portion of said doctor beam. 
     
     
         7 . The arrangement according to any  claim 1 , further comprising a hose pressurizing arrangement connected to said hose. 
     
     
         8 . The arrangement according to  claim 7 , further comprising a controller arranged for controlling said hose pressurizing arrangement. 
     
     
         9 . A twin-wire press for dewatering of a fiber suspension, comprising lower rolls, an endless lower wire, upper rolls and, an endless upper wire, and an arrangement for removal of a fiber web from at least one of said endless upper wire and said endless lower wire, said arrangement for removal of a fiber web in turn comprising:
 a doctor beam;   a doctor blade having a web contacting edge; and   a hose for fluids arranged for applying a force between said doctor beam and said doctor blade when being pressurized to move said web contacting edge towards said fiber conveying support;   said fiber web has a basis weight over 1000 g/m 2 ;   said doctor blade and said doctor beam being attached to each other by a pivotable attachment; and   said hose being arranged for applying said force at a distance from said pivotable attachment to move said web contacting edge by pivoting said doctor blade relative to said doctor beam.   
     
     
         10 . A method for operating an arrangement for removal of a fiber web from a fiber conveying support, comprising the steps of:
 pressurizing a hose for fluids arranged for applying a force between a doctor beam and a doctor blade to move a web contacting edge of said doctor blade towards said fiber conveying support;   pivoting said doctor blade relative to said doctor beam by applying said force at a distance from a pivotable attachment between said doctor beam and said doctor blade to provide said moving of said web contacting edge; and   controlling said pressurizing dependent on an operating condition of a device providing said fiber web.   
     
     
         11 . The arrangement according to  claim 2 , wherein said hose is applying said force on said doctor blade at a side opposite to said web contacting edge relative to said pivotable attachment. 
     
     
         12 . The arrangement according to  claim 3 , wherein said hose is applying said force on said doctor blade at a side opposite to said web contacting edge relative to said pivotable attachment. 
     
     
         13 . The arrangement according to  claim 2 , wherein said hose is a gas hose. 
     
     
         14 . The arrangement according to  claim 3 , wherein said hose is a gas hose. 
     
     
         15 . The arrangement according to  claim 4 , wherein said hose is a gas hose. 
     
     
         16 . The twin-wire press according to  claim 9 , wherein said hose is provided in a recess in said doctor blade and arranged to actuate on said doctor beam. 
     
     
         17 . The twin-wire press according to  claim 9 , wherein said hose is provided in a recess in said doctor beam and arranged to actuate on said doctor blade. 
     
     
         18 . The arrangement according to  claim 9 , wherein said hose is applying said force on said doctor blade at a side opposite to said web contacting edge relative to said pivotable attachment. 
     
     
         19 . The arrangement according to  claim 16 , wherein said hose is applying said force on said doctor blade at a side opposite to said web contacting edge relative to said pivotable attachment. 
     
     
         20 . The arrangement according to  claim 17 , wherein said hose is applying said force on said doctor blade at a side opposite to said web contacting edge relative to said pivotable attachment.