Method and apparatus in a paper or board machine for confining pulp flow from the headbox

Abstract

A method in a paper or board machine for confining a pulp flow coming from the headbox ( 1 ), in which by at least one deckle part ( 2 ) being above the wire in the operating position the pulp flow coming from the headbox is confined in the lateral direction in the edge area of the wire ( 3 ). In the method, by a support part ( 50 ) impervious to liquid being below the wire ( 3 ) together with the deckle part ( 2 ) into connection with which liquid is brought, a pressure effect is provided which furthers the sealing between the deckle board ( 2 ) and the wire ( 3 ) and intensifies the lubrication of at least one sealing surface of the deckle ( 2 ). The invention also relates to an apparatus.

1 . A method in a paper or board machine for confining a pulp flow coming from the headbox ( 1 ), in which by at least one deckle part ( 2 ) being above the wire in the operating position the pulp flow coming from the headbox is confined in the lateral direction in the edge area of the wire ( 3 ), characterised in that, in the method, by a support part ( 50 ) impervious to liquid being below the wire ( 3 ) together with the deckle into connection with which liquid is brought, a pressure effect is provided which furthers the sealing between the deckle boards ( 2 ) and the wire ( 3 ) and intensifies the lubrication of at least one sealing surface of the deckle ( 2 ). 
     
     
         2 . A method according to  claim 1 , characterised in that the support part ( 50 ) is arranged below the wire substantially at the point of the deckle ( 2 ) being above the wire ( 3 ). 
     
     
         3 . A method according to  claim 1 , characterised in that the support part ( 50 ) is a substantially machine-directional (MD) strip part. 
     
     
         4 . A method according to  claim 1 , characterised in that between the deckle ( 2 ) and the wire ( 3 ) is brought water from openings ( 17 ′) arranged in the deckle. 
     
     
         5 . A method according to  claim 1 , characterised in that between the deckle ( 2 ) and the wire ( 3 ) is brought water from the openings ( 17 ′) arranged in the deckle, whereby water is supplied at an angle α (alpha) from a perpendicular direction in relation to the plane of the wire ( 3 ) inclined in the travel direction of the wire. 
     
     
         6 . A method according to  claim 1 , characterised in that water is supplied in at least one groove ( 17 ) formed in the deckle ( 2 ), opening on the side of the wire ( 3 ). 
     
     
         7 . A method according to  claim 1 , characterised in that the deckle ( 2 ) comprises one or more seal parts ( 52 ,  54 ) between which there is a gap or a groove ( 17 ) in which liquid is brought. 
     
     
         8 . A method according to  claim 1 , characterised in that liquid is sprayed with at least one spraying head ( 57 ) in the gap ( 53 ) between the deckle ( 2 ) and the wire. 
     
     
         9 . A method according to  claim 1 , characterised in that the support part ( 50 ) is mainly planar on the side of the wire. 
     
     
         10 . A method according to  claim 1 , characterised in that the support part ( 50 ) is supported in a fastening surface ( 55 ) formed in a dewatering strip ( 51 ). 
     
     
         11 . An apparatus in a paper or board machine for confining a pulp flow coming from the headbox ( 1 ), which apparatus comprises at least one deckle part ( 2 ) being above the wire which in the operating position is arranged to confine the pulp flow coming from the headbox in the lateral direction in the edge area of the wire ( 3 ), characterised by a combination which comprises a support part ( 50 ) impervious to liquid being below the wire ( 3 ) and the deckle part ( 2 ) into connection with which liquid is brought such that a pressure effect is provided which furthers the sealing between the deckle board ( 2 ) and the wire ( 3 ) and intensifies the lubrication of at least one sealing surface of the deckle ( 2 ). 
     
     
         12 . An apparatus according to  claim 11 , characterised in that the support part ( 50 ) is arranged below the wire ( 3 ) substantially at the point of the deckle ( 3 ) being above the wire ( 3 ). 
     
     
         13 . An apparatus according to  claim 11 , characterised in that the support part ( 50 ) is a substantially machine-directional (MD) strip part. 
     
     
         14 . An apparatus according to  claim 11 , characterised in that in the deckle ( 2 ) are arranged openings ( 17 ′) from which water is brought between the deckle ( 2 ) and the wire ( 3 ). 
     
     
         15 . An apparatus according to  claim 11 , characterised in that in the deckle ( 2 ) are arranged the openings ( 17 ′) which are directed to spray water between the deckle ( 2 ) and the wire ( 3 ) at an angle a (alpha) from a perpendicular direction in relation to the plane of the wire ( 3 ) inclined in the travel direction of the wire. 
     
     
         16 . An apparatus according to  claim 11 , characterised in that, in the apparatus, water is supplied in at least one groove ( 17 ,  18 ) formed in the deckle ( 2 ), opening on the side of the wire ( 3 ). 
     
     
         17 . An apparatus according to  claim 11 , characterised in that the deckle ( 2 ) comprises one or more seal parts ( 52 ,  54 ) between which there is a gap or a groove ( 17 ) in which liquid is brought. 
     
     
         18 . An apparatus according to  claim 11 , characterised in that a fastening point ( 21 ) of the deckle part ( 2 ) at or in the vicinity of the end on the side of the headbox ( 1 ). 
     
     
         19 . An apparatus according to  claim 11 , characterised in that the support elements of the deckle comprise a support body ( 4 ) in which the deckle part is arranged in the longitudinal machine direction movably supported, particularly slidingly supported. 
     
     
         20 . An apparatus according to  claim 11 , characterised in that the support body ( 4 ) of the deckle is arranged movable between at least two positions, a first position i.e. operating position in which position the deckle confines the pulp flow in the lateral direction, and a second position i.e. maintenance position in which position the deckle has been moved upwards at least to a distance from the surface of the wire ( 3 ). 
     
     
         21 . An apparatus according to  claim 11 , characterised in that the support body ( 4 ) is arranged movable at least by an actuator ( 9 ) between the first position and the second position. 
     
     
         22 . An apparatus according to  claim 11 , characterised in that the moving devices of the support body ( 4 ) comprise a support part ( 5 ) which is arranged in a support structure ( 6 ) or equivalent of the machine and a first support arm ( 7 ) which is rotatably arranged in the support part ( 6 ) around a crosswise axis ( 8 ) of the machine, and further an actuator ( 9 ) which is arranged to move the support arm ( 7 ), in which support arm the support body ( 4 ) is arranged rotatably around a second crosswise axis ( 10 ). 
     
     
         23 . An apparatus according to  claim 11 , characterised in that in the second position the deckle part ( 2 ) is moved in the machine direction away from the headbox ( 1 ) and upwards from the plane of the wire ( 3 ). 
     
     
         24 . An apparatus according to  claim 11 , characterised in that the moving devices of the support body ( 4 ) comprise at least one adjustable stopper part ( 12 ) and a stop surface ( 13 ) for it, against which stopper the stop surface sets at least in the operating position. 
     
     
         25 . An apparatus according to  claim 11 , characterised in that the apparatus further comprises means for supplying water between the deckle part ( 2 ) and the wire ( 3 ). 
     
     
         26 . An apparatus according to  claim 11 , characterised in that on the surface of the deckle part ( 2 ) on the side of the wire ( 3 ) is formed at least one longitudinal groove ( 17 ) in which is arranged a liquid passage ( 17 ′) for supplying water. 
     
     
         27 . An apparatus according to  claim 11 , characterised in that the surface of the deckle part ( 2 ) on the side of the wire ( 3 ) is formed oblique, whereby between the wire ( 3 ) and the deckle part there is on the side of the edge of the wire a gap ( 53 ) which narrows in the cross machine direction at least towards one seal part ( 54 ). 
     
     
         28 . An apparatus according to  claim 11 , characterised in that the apparatus comprises at least one spray nozzle ( 57 ) for spraying liquid in the gap ( 53 ) between the deckle part ( 2 ) and the wire.