Sulzer-escher Wyss Limited

Escher Wyss Limited

Voith Sulzer Papiertechnik Patent Gmbh

Voith Sulzer Papiermaschinen Gmbh

Other

Hans K Dahl

Alfred Bubik

Rudiger Kurtz

Herbert Holik

Wolf-Gunter Stotz

Werner Seider

Peter Mirsberger

Elmer Weisshuhn

Karl Muller

Ulrich Begemann

Joachim Grabscheid

Volker Schmidt-Rohr

Robert Trondle

Anton Zembrot

Gerhard Kotitschke

Andreas Meschenmoser

David A Beck

Otto Hildebrand

Heinz Braun

Karl Josef B&ouml;ck

Thomas Elenz

Heinz Steckenreuter

Jorg Walter

Hannes Vomhoff

Dieter Egelhof

Wolfgang Mayer

Harald Hess

Josef Schneid

Wilfried Kraft

Johann Moser

Klaus Esslinger

Gunther Mohrhardt

Hans-J&uuml;rgen Wulz

Helmut Storr

Roger Wiedenmann

Thomas Schaible

Josef Dom

Jost Hefter

Process and apparatus for dewatering a fibrous material web. The process includes guiding the fibrous material web through a dewatering zone, and directing a plurality of gas pressure pulses of a pressurized displacement gas one after the other onto a surface of the fibrous material web within the dewatering zone. The apparatus includes a device for forming a plurality of gas pressure pulses which are arranged one after the other within the dewatering zone. The plurality of gas pressure pulses are directed onto a surface of the fibrous material web.

Process and device for dewatering a fibrous material web

Press device and process for treating a material web. The press device includes a first shoe press and a second shoe press. The first and the second shoe press are successively arranged in a web run direction. A transfer suction roll is positioned between the first shoe press and the second shoe press and is adapted to at least partially suction the material web and to guide the material web in a closed draw through at least one of the first and the second shoe presses. The process may includes at least partially suctioning the material web with the transfer suction roll, and guiding the material web in a closed draw through at least one of the first and the second shoe presses.

Press device and process for treating a material web

Apparatus and process for dewatering a material web. The apparatus includes at least one pressure chamber formed by at least four substantially parallel rolls, a device arranged to introduce a pressurized gas into the at least one pressure chamber, and the at least four substantially parallel rolls being displaceable relative to one another to change an effective area of the at least one pressure chamber. The material web is guided through the at least one pressure chamber. The process includes pressurizing at least one pressure chamber with a gas medium, guiding the material web through the pressure chamber, driving water out of the material web using gas pressure within the at least one pressure chamber, and changing an effective area of the pressure chamber so as to adjust a dewatering capacity.

Device for dewatering a material web

Wire section, guidance device, and process of forming a web in a machine for producing a fibrous material web. The device include two revolving endless wire belts, a twin wire zone formed between the two revolving endless wire belts, and a revolving flexible support belt located in a vicinity of the twin wire zone and positioned to support at least one of the two wire belts in a support region. The flexible support belt is generally guided along an at least essentially circular cylindrical path, and the support region includes a support path having an average curvature radius that is greater than a curvature radius of the essentially circular path. The process includes supporting at least one of the two endless wire belts with the flexible support belt in a support region, rotating the flexible support belt along a generally circular path, and deflecting the support belt from the generally circular path in the support region, whereby the support belt in the support regions travels along a support path. An average radius of curvature of the flexible support belt in the support path is greater than an average radius of curvature of the flexible support belt in the generally circular path.

Wire section, belt guidance device, and process for forming fibrous material web in wire section

Suction forming roll n double screen method and machine for the manufacture of a fibrous material web

A three layer headbox for producing a multilayer fiber web. The headbox has top and bottom walls inclined toward each other toward the outlet of the headbox. Top and a bottom separating blades in the headbox, the top blade defining a first chamber toward the top wall, the bottom blade being below defining a second chamber between the blades and also defining a third chamber between the bottom blade and the bottom wall. A respective pulp inlet to each of the three chambers. One of the top and bottom blades being hingedly supported at its upstream end to be adjustable in position for affecting the speed of pulp suspension in respective layers in the chambers affected by the orientation of the blade. The pulp suspension layers passing through a headbox are delivered to a paper machine forming section wire and the three streams from the headbox are combined directly before or upon impingement on the wire. Various velocities of the pulp suspension in each of the layers are obtainable and relatively adjustable with reference to each other.

Three-layer headbox

The invention concerns the wire section of a papermaking machine and a method of removing water from a fiber web in that section. A fiber suspension is discharged from a headbox on at least one and usually between two wires in the forming section. The fiber suspension is dewatered until it eventually reaches the point of immobility at which the fiber orientation is fixed. The rate of removal of water transverse to the direction of travel of the web is controlled at regions across the web. In particular, the rate of water removal is decreased at the edge regions of the wire and the web, as compared with the center region, to improve the transverse formation profile of the web. Various techniques for controlling the rate of water removal are disclosed including using different mesh of the wire at the edge regions and at the center region, a suction forming roll applying different levels of suction at different zones across the wire and the web, and adjustable ledges engaging one of the two wires and being adapted or adjusted to apply different pressure levels to the wire across the web.

Wire section and method of dewatering a fiber web in a wire section web

In a double wire former of a paper machine, a first continuous wire (1) is fed onto an at least partially curved guiding surface (4) so as to converge with a second wire (2), wherein the guiding surface (4) is movable in a form-locked manner relative to the wires. After the dewatering section described above, a further guiding surface (7) follows which, in advantageous embodiments, has an opposite sense of curvature and is fixedly located.

Double wire former

The invention pertains to a winding device for a fiber web having a carrier drum that is at least partially enveloped by the fiber web, wherein a carrier axis for the fiber web is adapted to fed or moved to the carrier drum and is adapted to contact the carrier drum jacket in an axially parallel winding position, with the goal being to further develop winding devices which limit the danger of web tearing and act against the formation of folds in the fiber webs, with this being achieved in that the fiber web is transferred, from a device, which device precedes the carrier drum in the web moving direction, together with a driving band, to the carrier drum and transferred there from the driving band to the carrier drum.

Winding device for a fiber web

In order to regulate dewatering of the fiber suspension and the formation of the paper web between the upper and lower wires of the papermaking machines, upper ledges are provided along with the upper wire. These upper ledges are particularly constructed so as to have uniform design. Between these upper ledges, there is left free the same distance or spacing. This distance is not smaller than the width of each upper ledge. The individual distances between the upper ledges can be closed by insertable inserts so that the dewatering can be forcibly accomplished at mutually separated zones. Along the lower wire, there are provided lower ledges at a table, and between these lower ledges, it can be adjusted varying distances or spacing therebetween. The mutual distance or spacing between the lower ledges, according to a favorable construction, is always greater than the width of the individual upper ledges plus the distance or spacing of an upper ledge from the next neighboring upper ledge. The lower ledges can be mounted at the table so as to be lengthwise displaceably and individually adjustable in the direction of the lower wire. The table can be selectably positioned vertically as well as horizontally relative to the lower wire. All of these measures also can be accomplished during operation of the papermaking machine. The individual lower ledges are elastically supported against the table and this table is elastically supported against its foundation. It is possible to undertake the web forming operation, during operation of the papermaking machines, in accordance with technological requirements and the time wise as well as localized situations, while protecting the paper web which is to be formed and equally the equipment which is to be operated.

Method of using a forming section of a papermaking machine

In a headbox for a paper machine a hydraulic headbox is combined with an apertured roller headbox, with at least one movable insert part (15) through which the material suspension (5) can flow being provided in the region of the flow channel (4) and/or of the nozzle channel (18) and with the flow channel (4) having a cross section through which flow takes place which broadens over at least a substantial part of its length in the direction of flow up to the moveable insert part (15).

Headbox for a paper-making machine

The wet section of a twin wire papermaking machine is provided with an open forming roll at the lower wire and with the combination of a suction box at the lower wire and a vacuum suction box at the upper wire. Furthermore, by selecting the elevational position or level of the individual wire sections there can be obtained particularly advantageous conditions for the operation of the papermaking machine throughout a wide field of application, especially heavy types of paper at relatively low operating velocities of the papermaking machine. Gap-former and hybrid-former constructions of the papermaking machine are possible.

Wet section for a twin wire papermaking machine

The de-watering apparatus for a two-wire paper machine is constructed in such a manner that following the convergence of both wires, firstly, a uniform pressure at a forming roll is exerted on the suspension layer located between the wires. Subsequently, both wires pass de-watering rails which may be located in the upper and/or the lower wire. In this case, an under-pressure is exerted at least at the rails located in the upper wire. At least one further de-watering member then follows before both wires are separated again. The de-watering apparatus can also be used after a preliminary de-watering section, for example an endless wire, and also in the direct vicinity of a head box.

De-watering apparatus in a two-wire former

Calendering takes place in a calendering zone which operates under pressure with application of temperature and moisture. The desired smoothness is achieved with a correspondingly long dwell time of the material web in a correspondingly long calendering zone in view of the speed of web travel. A web which is still wet is guided between parallel heatable surfaces which are arranged on both sides of the web and face each other through the web and can each be pressed against the web. The surfaces are designed to form and hold a given precise contour of the calendering zone over its full length. One surface is constructed e.g. as a casing of a heated roller and the second surface is constructed as an endless flexible belt which can be pressed in a direction towards the roller casing by means of a concave supporting element. If wished, the web can be calendered on both sides with the method.

Method for calendering a paper or cardboard web

For dewatering a paper web the pressing or press section has two separate or spaced pressing locations arranged in tandem and comprising extended nips. These pressing locations are each formed between an upper pressing surface and a lower pressing surface. The paper web to be dewatered travels between an upper felt belt and a lower felt belt. One of the felt belts extends through both pressing locations while the other felt belt only travels through the first pressing location as viewed in the direction of travel of the paper web. The paper web is only sandwiched between the two felt belts in the first pressing location. The other felt belt which is guided solely through the first pressing location is diverted away from the paper web directly downstream of the first pressing location by a pivotably mounted guide roll, so that the paper web passes through the second pressing location while being supported solely by the one felt belt guided through both pressing locations. Downstream of the second pressing location the paper web is deflected away from the one felt belt and conveyed to a drying section of the papermaking machine. In this manner, re-wetting of the paper web is reduced following each dewatering operation in the pressing locations. According to one embodiment the upper felt belt is guided through both pressing locations. The lower felt belt extends solely through the first pressing location.

Press section of a papermaking machine with adjustable felt guide roll

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Ravensburg, Germany

Hans K Dahl