Extension device for an air guide box

A method for producing a paper product in a paper production installation, the paper production installation including an air guide box having a flat uncovered exterior surface defining a stabilization surface that stabilizes and prevents speed-induced oscillations in a portion of a material web moving with high speed through the paper production installation, the air guide box characterised by a width in a width direction of the material web, a length in a length direction of the material web, and a height in a direction perpendicular to both the length and width directions of the material web, said method comprising:

• arranging the air guide box over or under the material web with a gap therebetween and with the stabilization surface of the air guide box facing the material web and extending substantially parallel thereto, the gap between the stabilization surface of the air guide box and the material web receiving a flow of air in a direction of running of the material web, producing a negative pressure between the material web and the stabilization surface which creates a stabilizing effect on the material web as it runs past the air guide box,
• providing an extension device having a height and a length that are less than the height and length, respectively, of the air guide box, the extension device comprising a plate that does not define an interior of another air guide box, the plate having at least one fastening side and at least one recess, said providing an extension device including determining a width of the extension device on a basis of the width of a particular side of the air guide box to which the extension device is to be attached;
• extending a dimension of the stabilization surface of the air guide box, and thus extending the stabilizing effect of the air guide box on the material web beyond said dimension of the stabilization surface, by attaching said extension device to the particular side of the air guide box, said attaching comprising aligning a surface of the plate with the stabilization surface of the air guide box and connecting the fastening side of the plate to the particular side of the air guide box in a flush manner with the surface of the plate extending in a substantially same plane as the stabilization surface, thus defining substantially the same gap between the material web and the surface of the plate as between the material web and the stabilization surface,
• cutting the material web extending in the longitudinal direction in the paper production installation using at least one high-pressure water jet or at least one laser beam generated by at least one cutting device proximal to the air guide box,
• wherein said cutting by the at least one high-pressure water jet or laser beam is effected proximal to the at least one recess in the plate of the extension device.

A method for producing a paper product in a paper production installation, comprising:

• arranging an air guide box over or under a web of paper with a gap therebetween, the air guide box characterised by a width in a width direction of the web of paper, a length in a length direction of the web of paper, and a height in a direction perpendicular to both the length and width directions of the web of paper;
• conveying the web of paper in a longitudinal direction along a flat uncovered exterior surface of the air guide box, the air guide box having an upstream end and a downstream end, the flat uncovered exterior surface being a stabilizing surface that extends substantially parallel to the web and that stabilizes and prevents speed-induced oscillations in a portion of the web as it moves with high speed through the paper production installation;
• receiving in the gap between the stabilizing surface and the web a flow of air in a direction of running of the web, producing a negative pressure between the web and the stabilizing surface which creates a stabilizing effect on the web as it runs past the air guide box;
• providing an extension plate having a height and a length that are less than the height and length, respectively, of the air guide box, the extension plate having at least one fastening side and at least one recess, said providing an extension plate including determining a width of the extension plate on a basis of the width of a particular side of the air guide box to which the extension plate is to be attached;
• extending a dimension of the stabilizing surface of the air guide box without using an additional air guide box, and thus extending the stabilizing effect of the air guide box on the web beyond said dimension of the stabilizing surface, by mounting said extension plate at the downstream end of the air guide box, said mounting comprising aligning a surface of the extension plate with the stabilization surface of the air guide box and connecting the fastening side of the extension plate to the downstream end of the air guide box in a flush manner with the surface of the extension plate extending in a substantially same plane as the stabilizing surface, thus defining substantially the same gap between the web and the surface of the extension plate as between the web and the stabilizing surface;
• and
• directing at least one high-pressure water jet or at least one laser beam through the at least one recess of the extension plate to cut the web of paper.