Voith Sulzer Papiermaschinen Gmbh

Voith Sulzer Papiertechnik Patent Gmbh

Voith Patent Gmbh

J. M. Voith Gmbh

Voith Paper Patent Gmbh

Loith Sulzer Papiermaschinen Gmbh

Hans Loser

Wolfgang Ruf

Klaus Lehleiter

Karl Steiner

Joachim Henssler

Albrecht Meinecke

Ulrich Begemann

Volker Schmidt-Rohr

Tri Chau-Huu

Konstantin Fenkl

Thomas Dietz

Udo Grossmann

Helmut Konecsny

Markus Häussler

Thomas Ruehl

Jürgen Prössl

Thomas Rühl

Marco Thomisch

Albrecht Bauder

Markus Häubler

Josef M&uuml;ellner

Thomas Elenz

Karl Bunz

Ole Hansen

Markus HÄUSSLER

Torben Schlieckau

Markus Häußler

Markus Haeussler

Axel Von Noorden

A method for operating a sheet-forming unit of a papermaking machine. At least one fibrous material suspension is fed to a headbox and is conducted in a plurality of turbulence-generating channels to form sub-flows, and fed to a nozzle. From the nozzle, the at least one fibrous material suspension is in the form of a free jet into the forming unit to define an impingement line. In a final fluidization region of an individual turbulence-generating channel a pressure loss (&#x394;p) of &#x2267;50 mbar is generated within the fibrous material suspension before inlet thereof into the nozzle, and the fibrous material suspension is guided from the final fluidization region as far as the impingement line in such a way that the dwell time of the suspension in the region defined by the final fluidization region as far as the impingement line ranges from &#x3e;30 ms to &#x2266;300 ms.

Method for operating a sheet-forming unit, and sheet forming unit

The invention relates to a headbox for a machine for producing a fibrous web, in particular a paper or cardboard web, from at least one fibrous stock suspension, having a feed apparatus which feeds the at least one fibrous stock suspension, having a distributor-pipe perforated plate which is adjacent downstream and has a multiplicity of channels which are arranged in rows and in columns, having an intermediate channel which lies downstream of the latter, extends over the width of the headbox and has a plurality of means which are spaced apart from one another in the width direction of the headbox for the preferably regulatable/controllable metering of a fluid in fluid part streams into the at least one fibrous stock suspension. The headbox according to the invention is characterized in that the means for the preferably regulatable/controllable metering of the fluid in fluid part streams into the at least one fibrous stock suspension is also configured for the preferably regulatable/controllable metering of at least one further fluid in fluid part streams into the at least one fibrous stock suspension, wherein the individual means comprises in each case a plurality of metering channels for the at least one further fluid, which metering channels have a respective metering-channel opening, open at different heights and are connected to a common supply channel.

Headbox for a machine for producing a fibrous web

Headbox for one of a paper and cardboard machine includes at least one material suspension supply running a width of the machine. At least one turbulence producer has at least one conduit through which a material suspension flows. At least one metered addition point is located in the conduit for introducing a fluid medium. A headbox nozzle is located downstream from the at least one turbulence producer for delivering the material suspension. A portion of a flow resistance located downstream of the metered addition point is at least approximately 50% of a total flow resistance of the at least one conduit.

Headbox for the metered addition of a fluid medium into a suspension stream

Lamella and headbox of a web production machine. The lamella is formed of at least one high-performance polymer. The at least one high-performance polymer includes high stability, high heat resistance, and good to very good resistance to at least one of alkaline solution and acid. The headbox includes the lamella.

Lamella of a headbox of a paper, cardboard, or tissue machine

Process of forming a headbox for a machine, which includes arranging a plurality of headbox channels into rows and columns, positioning a lamella between adjacent rows, fixing an end of the lamella at a fixing point, and arranging lamellar supports downstream of, relative to a headbox flow direction, the fixing point.

Process for forming headbox for a machine

Method for regulating a basis weight of a paper or cardboard web in the manufacturing process. The method includes determining a basis weight at an end of the manufacturing process, calculating a deviation of the determined basis weight from a predetermined target value, adjusting a concentration of a material suspension supplied to a headbox via a first control loop such that the calculated deviation is corrected, one of directly and indirectly measuring a basis weight of a resulting web in a region upstream, with regard to a web travel direction, a drying section, and supplying a signal related to the measured basis weight to a second control loop.

Method to control or regulate the basis weight of a paper or cardboard web

Process and a device for detecting a change in the fiber orientation cross-direction profile of a paper or cardboard web in the manufacturing process on a paper or cardboard machine. It is recognized that a change in the fiber orientation cross-direction profile in the web is inferred or determined by way of a characteristic change in the basis weight cross-direction profile or at least one measurement quantity that correlates to it, and/or by way of a characteristic change in the basis weight in the travel direction of the web or at least one measurement quantity that correlates to it. The device includes an arrangement for detecting a change in the basis weight cross-direction profile and/or a characteristic chronological course of the change in the basis weight, which is characteristic for a change in the fiber orientation.

Process for detecting and correcting a fiber orientation cross direction profile change

Headbox for a machine and process for forming the same. The headbox includes a plurality of channels arranged in rows that extend across a width of the machine and in columns substantially perpendicular to the rows, at least one lamella positioned between adjacent rows, a fixing point for the at least one lamella, and lamellar supports positioned after the fixing point, relative to a headbox flow. This includes arranging a plurality of headbox channels into rows and columns, positioning a lamella between adjacent rows, fixing an end of the lamella at a fixing point, and arranging lamellar supports downstream of, relative to a headbox flow direction, the fixing point.

Headbox

Process for a metered addition of a fluid medium into a material suspension stream of a headbox, including feeding the material suspension in a main flow direction through at least one turbulence-producing conduit to a headbox nozzle, the at least one turbulence-producing conduit having an entrance, a graduated pressure loss area, and an exit. A total pressure loss &Dgr;P is caused in the at least one turbulence-producing conduit such that the total pressure loss &Dgr;P includes at least one intake pressure loss &Dgr;P formed at the entrance and a graduated pressure loss &Dgr;P formed at the graduated pressure loss area. A metered addition of a fluid medium is also provided in a region between the entrance and the exit. The headbox for one of a paper and cardboard machine includes at least one material suspension supply running a width of the machine, at least one turbulence producer having at least one conduit through which a material suspension flows, at least one metered suspension supply running a width of the machine, at least one turbulence producer having at least one conduit through which a material suspension flows, at least one metered addition point located in the conduit for introducing a fluid medium, and a headbox nozzle located downstream from the at least one turbulence producer for delivering the material suspension. A portion of a flow resistance located downstream of the metered addition point is at least approximately 50% of a total flow resistance of the at least one conduit.

Headbox and process for the metered addition of a fluid medium into a suspension stream of a headbox

Paper or cardboard machine and method for regulating a basis weight of a paper or cardboard web in the manufacturing process. The paper or cardboard machine includes at least one headbox that extends across a machine width. The at least one headbox is adapted to provide a machine-wide distribution of a material suspension onto one of a screen and between two screens. The machine also includes at least one material suspension supply coupled to the at least one headbox and adapted to supply a material suspension to the at least one headbox. The at least one material suspension supply has at least one concentration. At least one first control loop is provided that includes at least one actuator being adapted to adjust the at least one concentration of the at least one material suspension supply, at least one detector for determining a basis weight of a finished web, at least one supply being adapted to modify the at least one concentration of the at least one material suspension supply, and at least one device that adjusts the at least one actuator. In this manner, the at least one concentration of the at least one material suspension supply is adjusted. At least one second control loop is provided that is adapted to regulate the concentration of the material suspension supply. The method includes determining a basis weight at an end of the manufacturing process, calculating a deviation of the determined basis weight from a predetermined target value, adjusting a concentration of a material suspension supplied to a headbox via a first control loop such that the calculated deviation is corrected, one of directly and indirectly measuring a basis weight of a resulting web in a region upstream, with regard to a web travel direction, a drying section, and supplying a signal related to the measured basis weight to a second control loop.

Device to control or regulate the basis weight of a paper or cardboard web

A method and machine for the manufacturing a fibrous pulp web including a first draining zone and a second draining zone, where the first and second draining zones are successively arranged in the web run direction, where a first side of the web is drained in the first draining zone by pressure acting on the web which increases from an initial pressure to a final pressure, where a second side of the web is drained in the second draining zone by pressure acting on the web which increases from an initial pressure to a final pressure in the web run direction, and where the initial pressure in the second draining zone is less than the final pressure in the first draining zone.

Method and machine for manufacturing a fibrous pulp web

Process for dewatering a fibrous web in a dewatering press including a counterpart face, a shoe press unit having a revolving flexible press belt and at least one press shoe such that the at least one press shoe is arranged to press the flexible press belt against the counterpart face, at least one nip formed by the flexible press belt being pressed against the counterpart face having a length extending in a web travel direction and being at least substantially similar to a length of the at least one press shoe in the web travel direction, and a device that guides the fibrous web and at least one dewatering belt being guided through the extended nip. The process may include pressing the fibrous web within the extended nip, determining a dwell time of the fibrous web within the extended nip, and maintaining the dwell time at less than approximately 12 ms. The dewatering press may include a counterpart face and a shoe press unit that includes a revolving flexible press belt and at least one press shoe. The at least one press shoe may be arranged to press the flexible press belt against the counterpart face. At least one nip may be formed by the flexible press belt being pressed against the counterpart face and may have a length extended in a web travel direction. The extended nip length in the web travel direction may be at least substantially similar to a length of the at least one press shoe in the web travel direction, and the fibrous web and at least one dewatering belt may be guided through the extended nip. The dewatering press may be arranged to provide a dwell time of the fibrous web being within the extended nip of less than approximately 12 ms.

Dewatering press and process

Press section of a machine for producing a fibrous web and process for pressing a fibrous web. The press section may include at least two shoe press units including at least one press shoe and a revolving flexible press belt, a counterpart face, at least two nips having a length extended in a web travel direction and formed by each at least one press shoe pressing the revolving flexible press belt against the counterpart face. A length of the extended nip may be at least substantially the same as a length of the at least press shoe length, measured in the web travel direction, forming the extended nip and at least one of the shoe press units having press shoe length different from the other shoe press units, whereby various extended nip length are formed. The process may include positioning a first of the at least two nips upstream, with respect to the web travel direction, a last of the at least two nips, wherein one of the first and last nips has a nip length greater than the other and applying different pressing forces in the at least two nips such that the one of the first and last nip having a greater length has a lesser pressing force applied.

Press section and method for pressing with different shoe press lengths

Device for detecting and correcting a fiber orientation cross direction profile change

An apparatus and a process for controlling or regulating a web property profile of a paper or cardboard web produced in the manufacturing process of a paper or cardboard machine is disclosed. The apparatus incorporates information regarding the position of one or more devices of a plurality of adjustable devices for sectionally manipulating at least one web property for regulating or controlling the devices to manipulate at least one web property across the width of the machine. The process includes combing the regulating process or a regulator device for adjusting individual actuators that only act on a certain section of conventional systems with the adjustment of an actuator acting across the entire web width for achieving a certain web property, so that the sectionally-operating actuators are not located in an end-position, so that these sectional actuators continue to be able to adjust the web property.

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Langenau, Germany

Hans Loser