20110259540 | DOUBLE-LAYER HEADBOX FOR A MACHINE FOR PRODUCING A DOUBLE-LAYER FIBROUS WEB - The invention relates to a dual-layer material ramp for a machine for producing a dual-layered fibrous web, in particular a dual-layered paper or cardboard web, from two fibrous suspensions, comprising a material ramp nozzle with two nozzle spaces extending along the width and separated from one another on the inside by a separating wedge, said nozzle spaces guiding a respective fibrous suspension during operation of the dual-layer material ramp as fibrous suspension streams and coming together, each of said nozzle spaces comprising an upstream feed device, a downstream outlet gap with a gap width, said gap extending along the width and an outer wall on the outside, wherein the separating wedge comprises two separating wedge surfaces that are contacted by the respective fibrous suspension stream during operation of the dual-layer material ramp. The dual-layer material ramp according to the invention is characterized in that the separating wedge comprises two separating wedge areas, each having a separating wedge angle, an upstream separating wedge starting area and a downstream separating wedge end area, that the two separating wedge angles of the two separating wedge areas assume different angular values, wherein the separating wedge starting angle of the upstream separating wedge starting area assumes a greater angular value than the separating wedge end angle of the downstream separating wedge end area, and that a non-planar transition area is provided between at least one separating wedge surface of the separating wedge between the two separating wedge areas of the separating wedge. | 10-27-2011 |
20110303382 | SHEET FORMING SYSTEM FOR A MACHINE FOR PRODUCING A MULTILAYER FIBROUS WEB - The invention relates to a sheet-forming system for a machine for producing a multilayer fibrous material web, comprising a multilayer headbox having a headbox nozzle, which has at least two nozzle chambers that are separated from one another by at least one separating wedge, and further comprising a gap former, which is connected directly downstream of the multilayer headbox and has two continuous revolving screens, the first screen of which runs over a circumferential area of a forming roll and the second screen of which runs over a circumferential area of a breast roll and then runs onto the first screen in the area of the forming roll to form a wedge-shaped material inlet gap. The sheet-forming system according to the invention is characterized in that the separating wedge has a separating wedge protrusion in a range of 0.05 to 3.0 of the largest single gap width of the at least two nozzle chambers; the separating wedge comprises two separating wedge areas, each having one separating wedge angle, an upstream separating wedge starting area and a downstream separating wedge ending area; the two separating wedge angles of the two separating wedge areas assume different angle values, wherein the separating wedge starting angle of the upstream separating wedge initial area assumes a greater angle value than the separating wedge ending angle of the downstream separating wedge end area, and at least one separating wedge surface of the separating wedge is provided as a nonplanar transitional area between the two separating wedge areas of the separating wedge; the fibrous material suspension free jet formed from at least two fibrous material suspension streams has a free jet length in the range of 100 to 500 mm, and the forming roll has a diameter in the range of 1,200 to 2,500 mm. | 12-15-2011 |