CA2106355A1 - Double wire former with locally adjustable dewatering slat - Google Patents
Double wire former with locally adjustable dewatering slatInfo
- Publication number
- CA2106355A1 CA2106355A1 CA 2106355 CA2106355A CA2106355A1 CA 2106355 A1 CA2106355 A1 CA 2106355A1 CA 2106355 CA2106355 CA 2106355 CA 2106355 A CA2106355 A CA 2106355A CA 2106355 A1 CA2106355 A1 CA 2106355A1
- Authority
- CA
- Canada
- Prior art keywords
- dewatering
- slat
- double wire
- wire
- zone
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Classifications
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21F—PAPER-MAKING MACHINES; METHODS OF PRODUCING PAPER THEREON
- D21F1/00—Wet end of machines for making continuous webs of paper
- D21F1/48—Suction apparatus
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21F—PAPER-MAKING MACHINES; METHODS OF PRODUCING PAPER THEREON
- D21F1/00—Wet end of machines for making continuous webs of paper
- D21F1/48—Suction apparatus
- D21F1/483—Drainage foils and bars
- D21F1/486—Drainage foils and bars adjustable
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21F—PAPER-MAKING MACHINES; METHODS OF PRODUCING PAPER THEREON
- D21F9/00—Complete machines for making continuous webs of paper
- D21F9/003—Complete machines for making continuous webs of paper of the twin-wire type
Landscapes
- Paper (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
A double wire former for producing a fiber web, specifically a paper web, from a fiber suspension. The double wire former includes two wires which together form a double wire, at least one double wire dewatering zone, and at least one dewatering slat in the double wire dewatering zone. The at least one dewatering slat is provided with a number of adjustment devices across the width of the paper web which influence, limited in width, the position of the contact surface of the dewatering slat.
A double wire former for producing a fiber web, specifically a paper web, from a fiber suspension. The double wire former includes two wires which together form a double wire, at least one double wire dewatering zone, and at least one dewatering slat in the double wire dewatering zone. The at least one dewatering slat is provided with a number of adjustment devices across the width of the paper web which influence, limited in width, the position of the contact surface of the dewatering slat.
Description
3 ~ ~
DOUBLJ~: WIRE FOl~ME]R WIT}~ LOCALLY
ADJUSTABLE: DEWATERING SLAT
BACK~:ROUND OF T~HE INVENTION
The invention concerns a doubl~ wire former for producing a fiber web, specifically a paper web, from a fiber suspension.
The invention is based on the double wire former known from the British patent document 1,125,906. The characteristics known from this publication are providing two wires which together form a double wire, providing at least one double wire dewatering zone, and providing at least one dewatering slat in the double wire dewatering zone. This publication illustrates a double wire former which, in a first section of the double wire zone, ~o~ms with the two wires a wedge-shaped entrance gap. A jet of stock suspension coming from the headbox empties into it, impinging on the two wires at a point where they run across a curved dewatering element. In the case o~ the said British pate~t document, this element is a stationary, curved forming shoe~ Its curved wire support surface is formed of numerous slats with interposed dewatering slots. This forming shoe is followed (in a ~econd section of the double wire zone) by a dewatering slat arranged in the other wire loop and, behind it, a dewatering ~lat arranged in the former wire loop (and formed by a first suction box). Lastly, ~ollowing in a third section of the double wire zone are several stationary dewatering elements fashioned as suction flat boxes~
Using double wire formers of the prior type, attempts have already been made for decades at producing fiber webs (specifically paper webs) of maximally high quality and at relatively high operating speeds. The web formation between two wires has achieved, in particular~
a finished fiber web which possesses on both sides extensively the same properties (slight "twosidedness").
However, difficulties are encolmtered in achieving a maximally uniform fiber distribution in the finished fiber web. In other words, it is difficult to achieve a good "formation." During the web formation there constantly exists the risk that ~ibers will coagulate to flocks. Therefore, attempts are made to form at the headbox a maximally flock-free jet of stock suspension (for instance with the aid of a turbulence generator).
In addition, efforts are being made toward influencing the dewatering of the fiber suspension during web formation to the effect that a "reflocculation" is maximally avoided or that after any flock formation a "deflocculation" (i.e., dissolution of the flocks) occurs again.
It is known that a curved d~watering element arranged in the first section of the double wire zone, specifically a stationary, curved forming shoe fashioned according to the British patent document 1,125,906, counteracts the risk of reflocculation. This is true also for the dewatering slats which acc~rding to the British patent document are arranged in the second ection of the double wire zone. Nevertheless, the risk of reflocculation is not completely eliminated with the arrangement according to this British patent document.
Namely t with the number of dewa~ering slats being very small there, the web formation largely takPs place ln the area of the following suction flat boxes. While these have a high dewatering capacity so that the web formation can be terminated in the area of the last ~uction flat box (i.e., the so-called major dewatering zone in which part of the fiber material still on hand in the form of a suspension ends in the area of the suction flat boxes), 3 ~ ~
the suction flat boxes are unable to avoid a reflocculation or to redissolv~e flocks which have been created.
To master the latter difficultles, a web forming system known as "Duoformer Dl~:has been developed (TAPPI
Proceedings 1988 Annual Meeting, pp. 75-80~. This prior web forming system is part of a double wire former featuring a sin~le wire primary dewatering zone.
Provided in the double wire zone, in the one wire loop, is a number of fixed but adjustably supported slats on the underside of a suction flat box dewatering upwardly.
In addition, a number of flexibly supported slats are provided in the other wire loop. Due to the flexibility of the latter slats, the following can be achieved. For instance, at an increase of the suspension quantity fed between the two wires, the flexibly supported slats can somewhat yi~ld. This eliminates the risk (which exis~s when fixedly supported slats are solely used) that a backup will form in the fiber suspension in front of the slats. Such backup could again destroy the fiber layers formed up to here on the two wires. In other words, a dewatering pressure once adjusted remains constant with this web forming system, owing to the flexibly supported slats, also at a change of the supplied suspension quantity or of the dewatering performance of the fiber suspension. Thus, an automatic adaptation of the web forming system to the said changed conditions is taking place.
Fiber w~bs with relatively good formation can be formed with this prior web forming system. Requirements have recently risen considerably, however, making further improvements desirable. It would be a considerable improvement of the sheet forming mechanism if the basis weight cross profile and the fiber orientation cross profile were more specific and influenceable at the points where the defects occur.
First variations, or defects, in the basis weight and fiber orientation cross profiles occur in the headbox. From the German patent disclosure DE 31 09 227 A1, for example, it is known that variations o~ the basis weight cross profile from the ideal condition are corrected by adjustments on the headbox profile bar. In the aforementioned patent disclosure, the basis weight cross profile is influenced by bending the headbox profile bar directly at the slice, in such a way that both errors that have nccurred in setting the headbox and errors which in the subsequent course of the paper machine occur in the dewatering zone, for instance by nonuniform contact pressure in the press section or nonuniform contact pressure of dewatering slats, will thereby be eliminated.
For onel however, it is technically unsatisfactory to compensate for defects occurring at one point of the machine by "maladjustments," seen in the ideal sense at another point of the paper machine; for another, this also entails the problem that adjustments made with regard to the basis weight cross profile will undesirably in~luence, as the case may be, the fiber orientation of the paper web.
The problem underlying the invention is to design a double wire former of the initially described type such that defects in the basis weight cross pro~ile which occur through peculiarities of the dewatering zone also will be in~luenced, or corrected, within the dewatering zone.
SUMMARY OF THE INVENTION
This problem is solved by the inventive features of the present invention. A number of adjustment devices 2 ~
are provided for a dewatering slat across the width of the paper web, wherein each adjustment device, for a limited width, allows for influencing the position of the contact surface of the dewatering slat.
The inventors have recognized that it is possible to influence the basis weight croRs profile o~ a fiber web in the area of the dewatering zone through the use of one or several flexible dewatering slats whose position is individually adjustable, across the entire width of the web, nearly or approximately perpendicularly to the travel direction of the wire.
BRIEF DESCRIPTION OF THE_DRAWINGS
The invention will be more fully explained with the aid of the drawings.
Eigs. 1 and 2 show two embodiments of the adjustable dewatering slat.
Eig. 3 shows an embodiment of a flexural slat of two materials.
Fig. 4 shows a flexibly arranged dewatering slat.
Figs. 5 through 7 show various positions for arrangement of the adjustable dewatering slat.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Fig. 1 shows one embodiment of the dewatering slat where the flexural slat B is forced on the wire by a spindle type actuator in keeping with setting requirements. Fig. 1 shows a cross section of this device, where the device consists of a stable body having approximately the shape of a flat U-profile through the short topside of which holes are tapped matching the number of actuators. A threaded spindle S is passed - through each hole. Threaded spindle S connects via a holder H in the form of a claw with a deflector slat D, which in turn bears on the lower short side of the U-profile. The part of the U-profile now remaining open 3 ~ ~
is covered by a contact plate A across the machine width, causing the deflector slat to be forced on the U-profile at its underside. The spindles are each adjustable through a device V. The de~lector slat slidably mounted between the guide element F and the contact plate A can be positionally adjusted with the aid of the pindle/
causing the slat to exert variable pressure on the wires Sl and S2 passing beneath it.
Fig. 2 shows another embodiment of the dewatering slat described by the invention. Illustrated in cross section in Fig. 2 is a deflector slat D deflected at an angle ~ to the vertical and bearing on a wire S1 situated underneath. On its nonbearing side, the deflector slat is retained by a holder H in ths fonn of a claw. Holder H is in turn attached to a guide body having approximately the shape of a flat iron, such that the guide body and deflector slat assume the shape of a lying, left-opening V whose topside i9 situated parallel to the wire passing beneath. A number of tapped bores are again provided in the guide body, through which the spindles, adjusted by the device V, bear down on the deflector slat, again enabling the position-dependent adjustm~nt of the deflector slat.
Fig. 3 shows schematically the embodiment of the deflector slat corresponding to the shape illustrated in Fig. 1 where the deflector slat consists of two materials. The slat includes an upper continuous, flexurally elastic material B where the spindles S are arranged on the topside with the aid of claws. On the opposite sicle there are a number of individual elements set side by side which consist of a more resistant, more brittle material E and which bear dir ctly on the wire.
A relatively high flexibility of the overall slat, and a good wear performance, is thereby achieved.
3 ~ ~
Fig. 4 shows a dewatering slat similar to Fig. 1, but here the guide element F connects with a carrier T by way of a web S arranged on the underside. Two pressure cushions are arranged bstween the guide element F and carrier ~ The size of the pressure cushions can be adjusted by application of different pressures, such that the guide element F, in relation to the carrier, can move in its entirety, thus exerting on the wire an adjustable, flexible pressure. In the present form, th~ two pressure cushions are prevented from slipping out of the intermediate gap between the guide element and carrier by slats arranged above them.
Fig. 5 shows in exemplary fashion the sheet formation zone of a double wire former with a headbox coming ~rom the left and injecting its fiber suspension between two wires Sl and S2 passing over two reversing cylinders Zl and Z2. The two wires S1 and S2 extend in sandwich fashion across a dewatering unit E, behind which a locally adjustable dewatering slat according to the invention is provided. The locally adjustable dewatering slat is bearing from above.
Fig. 6 shows a double wire former as well. In this embodiment, the stock suspension is injected between two wires from below. The two reversing cylinders Zl and 22 carrying the wires are situated with their axes on a nearly horizontal plane, whereby the wire Sl coming from above is deflected to the right, first across cylinder Z1 and thent bearing on wire S2, across cylinder Z2. In this embodiment, there are two inven~ional dewatering slats Ll and L2 provided at a mutual offset, above and below the w:ire, bordering directly on the cylinder Z2.
Fig. 7 once again shows a headbox of a double wire former, this time with a primary dewatering. Coming from the left, the headbox applies the stock suspension on the p ~
wire S2 which, coming from below, is de~lected via cylinder Z2 and is passed to the dewatering zone El.
Following the dewatering zone E1, a wire S1 is moved across cylinder Zl ~rom above and, with a steadily diminishing gap, to the wire S2. Both wires run to a double-sided dewatering zone 2, and wire Sl is then deflected upward via cylinder Z3 while wire S2 is deflected downward via cylinder Z4. This embodiment proposes placing an inventional dewatering slat L between reversing cylinder Zl and the double-sided dewatering zone E2 on the topside o~ wire S1, and the slat~ on the lower wire in the dewatering zone E2.
DOUBLJ~: WIRE FOl~ME]R WIT}~ LOCALLY
ADJUSTABLE: DEWATERING SLAT
BACK~:ROUND OF T~HE INVENTION
The invention concerns a doubl~ wire former for producing a fiber web, specifically a paper web, from a fiber suspension.
The invention is based on the double wire former known from the British patent document 1,125,906. The characteristics known from this publication are providing two wires which together form a double wire, providing at least one double wire dewatering zone, and providing at least one dewatering slat in the double wire dewatering zone. This publication illustrates a double wire former which, in a first section of the double wire zone, ~o~ms with the two wires a wedge-shaped entrance gap. A jet of stock suspension coming from the headbox empties into it, impinging on the two wires at a point where they run across a curved dewatering element. In the case o~ the said British pate~t document, this element is a stationary, curved forming shoe~ Its curved wire support surface is formed of numerous slats with interposed dewatering slots. This forming shoe is followed (in a ~econd section of the double wire zone) by a dewatering slat arranged in the other wire loop and, behind it, a dewatering ~lat arranged in the former wire loop (and formed by a first suction box). Lastly, ~ollowing in a third section of the double wire zone are several stationary dewatering elements fashioned as suction flat boxes~
Using double wire formers of the prior type, attempts have already been made for decades at producing fiber webs (specifically paper webs) of maximally high quality and at relatively high operating speeds. The web formation between two wires has achieved, in particular~
a finished fiber web which possesses on both sides extensively the same properties (slight "twosidedness").
However, difficulties are encolmtered in achieving a maximally uniform fiber distribution in the finished fiber web. In other words, it is difficult to achieve a good "formation." During the web formation there constantly exists the risk that ~ibers will coagulate to flocks. Therefore, attempts are made to form at the headbox a maximally flock-free jet of stock suspension (for instance with the aid of a turbulence generator).
In addition, efforts are being made toward influencing the dewatering of the fiber suspension during web formation to the effect that a "reflocculation" is maximally avoided or that after any flock formation a "deflocculation" (i.e., dissolution of the flocks) occurs again.
It is known that a curved d~watering element arranged in the first section of the double wire zone, specifically a stationary, curved forming shoe fashioned according to the British patent document 1,125,906, counteracts the risk of reflocculation. This is true also for the dewatering slats which acc~rding to the British patent document are arranged in the second ection of the double wire zone. Nevertheless, the risk of reflocculation is not completely eliminated with the arrangement according to this British patent document.
Namely t with the number of dewa~ering slats being very small there, the web formation largely takPs place ln the area of the following suction flat boxes. While these have a high dewatering capacity so that the web formation can be terminated in the area of the last ~uction flat box (i.e., the so-called major dewatering zone in which part of the fiber material still on hand in the form of a suspension ends in the area of the suction flat boxes), 3 ~ ~
the suction flat boxes are unable to avoid a reflocculation or to redissolv~e flocks which have been created.
To master the latter difficultles, a web forming system known as "Duoformer Dl~:has been developed (TAPPI
Proceedings 1988 Annual Meeting, pp. 75-80~. This prior web forming system is part of a double wire former featuring a sin~le wire primary dewatering zone.
Provided in the double wire zone, in the one wire loop, is a number of fixed but adjustably supported slats on the underside of a suction flat box dewatering upwardly.
In addition, a number of flexibly supported slats are provided in the other wire loop. Due to the flexibility of the latter slats, the following can be achieved. For instance, at an increase of the suspension quantity fed between the two wires, the flexibly supported slats can somewhat yi~ld. This eliminates the risk (which exis~s when fixedly supported slats are solely used) that a backup will form in the fiber suspension in front of the slats. Such backup could again destroy the fiber layers formed up to here on the two wires. In other words, a dewatering pressure once adjusted remains constant with this web forming system, owing to the flexibly supported slats, also at a change of the supplied suspension quantity or of the dewatering performance of the fiber suspension. Thus, an automatic adaptation of the web forming system to the said changed conditions is taking place.
Fiber w~bs with relatively good formation can be formed with this prior web forming system. Requirements have recently risen considerably, however, making further improvements desirable. It would be a considerable improvement of the sheet forming mechanism if the basis weight cross profile and the fiber orientation cross profile were more specific and influenceable at the points where the defects occur.
First variations, or defects, in the basis weight and fiber orientation cross profiles occur in the headbox. From the German patent disclosure DE 31 09 227 A1, for example, it is known that variations o~ the basis weight cross profile from the ideal condition are corrected by adjustments on the headbox profile bar. In the aforementioned patent disclosure, the basis weight cross profile is influenced by bending the headbox profile bar directly at the slice, in such a way that both errors that have nccurred in setting the headbox and errors which in the subsequent course of the paper machine occur in the dewatering zone, for instance by nonuniform contact pressure in the press section or nonuniform contact pressure of dewatering slats, will thereby be eliminated.
For onel however, it is technically unsatisfactory to compensate for defects occurring at one point of the machine by "maladjustments," seen in the ideal sense at another point of the paper machine; for another, this also entails the problem that adjustments made with regard to the basis weight cross profile will undesirably in~luence, as the case may be, the fiber orientation of the paper web.
The problem underlying the invention is to design a double wire former of the initially described type such that defects in the basis weight cross pro~ile which occur through peculiarities of the dewatering zone also will be in~luenced, or corrected, within the dewatering zone.
SUMMARY OF THE INVENTION
This problem is solved by the inventive features of the present invention. A number of adjustment devices 2 ~
are provided for a dewatering slat across the width of the paper web, wherein each adjustment device, for a limited width, allows for influencing the position of the contact surface of the dewatering slat.
The inventors have recognized that it is possible to influence the basis weight croRs profile o~ a fiber web in the area of the dewatering zone through the use of one or several flexible dewatering slats whose position is individually adjustable, across the entire width of the web, nearly or approximately perpendicularly to the travel direction of the wire.
BRIEF DESCRIPTION OF THE_DRAWINGS
The invention will be more fully explained with the aid of the drawings.
Eigs. 1 and 2 show two embodiments of the adjustable dewatering slat.
Eig. 3 shows an embodiment of a flexural slat of two materials.
Fig. 4 shows a flexibly arranged dewatering slat.
Figs. 5 through 7 show various positions for arrangement of the adjustable dewatering slat.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Fig. 1 shows one embodiment of the dewatering slat where the flexural slat B is forced on the wire by a spindle type actuator in keeping with setting requirements. Fig. 1 shows a cross section of this device, where the device consists of a stable body having approximately the shape of a flat U-profile through the short topside of which holes are tapped matching the number of actuators. A threaded spindle S is passed - through each hole. Threaded spindle S connects via a holder H in the form of a claw with a deflector slat D, which in turn bears on the lower short side of the U-profile. The part of the U-profile now remaining open 3 ~ ~
is covered by a contact plate A across the machine width, causing the deflector slat to be forced on the U-profile at its underside. The spindles are each adjustable through a device V. The de~lector slat slidably mounted between the guide element F and the contact plate A can be positionally adjusted with the aid of the pindle/
causing the slat to exert variable pressure on the wires Sl and S2 passing beneath it.
Fig. 2 shows another embodiment of the dewatering slat described by the invention. Illustrated in cross section in Fig. 2 is a deflector slat D deflected at an angle ~ to the vertical and bearing on a wire S1 situated underneath. On its nonbearing side, the deflector slat is retained by a holder H in ths fonn of a claw. Holder H is in turn attached to a guide body having approximately the shape of a flat iron, such that the guide body and deflector slat assume the shape of a lying, left-opening V whose topside i9 situated parallel to the wire passing beneath. A number of tapped bores are again provided in the guide body, through which the spindles, adjusted by the device V, bear down on the deflector slat, again enabling the position-dependent adjustm~nt of the deflector slat.
Fig. 3 shows schematically the embodiment of the deflector slat corresponding to the shape illustrated in Fig. 1 where the deflector slat consists of two materials. The slat includes an upper continuous, flexurally elastic material B where the spindles S are arranged on the topside with the aid of claws. On the opposite sicle there are a number of individual elements set side by side which consist of a more resistant, more brittle material E and which bear dir ctly on the wire.
A relatively high flexibility of the overall slat, and a good wear performance, is thereby achieved.
3 ~ ~
Fig. 4 shows a dewatering slat similar to Fig. 1, but here the guide element F connects with a carrier T by way of a web S arranged on the underside. Two pressure cushions are arranged bstween the guide element F and carrier ~ The size of the pressure cushions can be adjusted by application of different pressures, such that the guide element F, in relation to the carrier, can move in its entirety, thus exerting on the wire an adjustable, flexible pressure. In the present form, th~ two pressure cushions are prevented from slipping out of the intermediate gap between the guide element and carrier by slats arranged above them.
Fig. 5 shows in exemplary fashion the sheet formation zone of a double wire former with a headbox coming ~rom the left and injecting its fiber suspension between two wires Sl and S2 passing over two reversing cylinders Zl and Z2. The two wires S1 and S2 extend in sandwich fashion across a dewatering unit E, behind which a locally adjustable dewatering slat according to the invention is provided. The locally adjustable dewatering slat is bearing from above.
Fig. 6 shows a double wire former as well. In this embodiment, the stock suspension is injected between two wires from below. The two reversing cylinders Zl and 22 carrying the wires are situated with their axes on a nearly horizontal plane, whereby the wire Sl coming from above is deflected to the right, first across cylinder Z1 and thent bearing on wire S2, across cylinder Z2. In this embodiment, there are two inven~ional dewatering slats Ll and L2 provided at a mutual offset, above and below the w:ire, bordering directly on the cylinder Z2.
Fig. 7 once again shows a headbox of a double wire former, this time with a primary dewatering. Coming from the left, the headbox applies the stock suspension on the p ~
wire S2 which, coming from below, is de~lected via cylinder Z2 and is passed to the dewatering zone El.
Following the dewatering zone E1, a wire S1 is moved across cylinder Zl ~rom above and, with a steadily diminishing gap, to the wire S2. Both wires run to a double-sided dewatering zone 2, and wire Sl is then deflected upward via cylinder Z3 while wire S2 is deflected downward via cylinder Z4. This embodiment proposes placing an inventional dewatering slat L between reversing cylinder Zl and the double-sided dewatering zone E2 on the topside o~ wire S1, and the slat~ on the lower wire in the dewatering zone E2.
Claims (4)
1. A double wire former for producing a fiber web from a fiber suspension, the double wire former comprising:
two wires which together form a double wire;
at least one double wire dewatering zone;
at least one dewatering slat in the double wire dewatering zone, the at least one dewatering slat further comprising a contact surface; and a plurality of adjustment devices distributed across the width of the web, wherein each adjustment device allows for influencing the position of the contact surface of the dewatering slat for a portion of the web.
two wires which together form a double wire;
at least one double wire dewatering zone;
at least one dewatering slat in the double wire dewatering zone, the at least one dewatering slat further comprising a contact surface; and a plurality of adjustment devices distributed across the width of the web, wherein each adjustment device allows for influencing the position of the contact surface of the dewatering slat for a portion of the web.
2. The double wire former of claim 1 further comprising means distributed substantially across the width of the double wire former which influence position specifically the contact pressure of the at least one dewatering slat on the wire.
3. The double wire former of claim 1 wherein the two wires forming the double wire are situated such that a fiber suspension is injected from a headbox between said two wires, said fiber suspension having a basis weight profile and said headbox including a spindle position, further comprising a control device for controlling the contact pressure of the dewatering slat on the wire or for controlling an adjustment height of the dewatering slat, said control device being actuable to effect said control in contingence upon the basis weight profile or spindle position of the headbox.
4. A double wire former for producing a fiber web, comprising:
two wires which together form a double wire;
at least one double wire dewatering zone;
at least one dewatering slat in the double wire dewatering zone; and a plurality of adjustment devices provided across the width of the dewatering slat for influencing the position of the contact surface of the dewatering slat, each limited in width.
two wires which together form a double wire;
at least one double wire dewatering zone;
at least one dewatering slat in the double wire dewatering zone; and a plurality of adjustment devices provided across the width of the dewatering slat for influencing the position of the contact surface of the dewatering slat, each limited in width.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE9212448U DE9212448U1 (en) | 1992-09-16 | 1992-09-16 | Double wire former with locally adjustable drainage bar |
| DEG9212448.8 | 1992-09-16 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2106355A1 true CA2106355A1 (en) | 1994-03-17 |
Family
ID=6883799
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA 2106355 Abandoned CA2106355A1 (en) | 1992-09-16 | 1993-09-16 | Double wire former with locally adjustable dewatering slat |
Country Status (6)
| Country | Link |
|---|---|
| JP (1) | JPH06207397A (en) |
| AT (1) | AT402746B (en) |
| CA (1) | CA2106355A1 (en) |
| DE (3) | DE9212448U1 (en) |
| FI (1) | FI934033A (en) |
| SE (1) | SE9302926L (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5552021A (en) * | 1993-06-17 | 1996-09-03 | Valmet Corporation | Method, device and arrangement for regulating the control of a transverse profile of a paper web in a paper machine |
| US6027612A (en) * | 1996-09-11 | 2000-02-22 | Voith Sulze Papiermaschinen Gmbh | Wire section and method of dewatering a fiber web in a wire section web |
| US6361657B2 (en) | 1999-11-17 | 2002-03-26 | Mcpherson Douglas R. | Twin fabric forming section blade mounting |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE29619709U1 (en) * | 1996-11-13 | 1997-01-09 | Voith Sulzer Papiermaschinen GmbH, 89522 Heidenheim | Screen section of a paper machine |
| DE19652485A1 (en) * | 1996-12-17 | 1998-06-18 | Voith Sulzer Papiermasch Gmbh | Paper-making machine fourdrinier section |
| DE10333201A1 (en) * | 2003-07-22 | 2005-02-24 | Voith Paper Patent Gmbh | Papermaking dewatering double sieve belt passes over transverse pressure beam subdivided into equal segments with individual pressure control |
| DE102005000175A1 (en) * | 2005-12-05 | 2007-06-06 | Voith Patent Gmbh | Strip for the flexible support of a sieve and a double sieve section |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3815470A1 (en) * | 1988-05-06 | 1989-11-16 | Voith Gmbh J M | DOUBLE SCREEN SHAPER |
| FI885606A (en) * | 1988-12-01 | 1990-06-02 | Ahlstroem Valmet | BANFORMNINGSFOERFARANDE OCH ANORDNING. |
| DE3927597A1 (en) * | 1989-08-22 | 1991-02-28 | Voith Gmbh J M | DOUBLE SCREEN SHAPER |
| DE4002305C2 (en) * | 1990-01-26 | 1996-02-22 | Voith Sulzer Papiermasch Gmbh | Drainage device on a twin wire former |
-
1992
- 1992-09-16 DE DE9212448U patent/DE9212448U1/en not_active Expired - Lifetime
- 1992-11-19 DE DE4238885A patent/DE4238885A1/en not_active Withdrawn
-
1993
- 1993-09-09 DE DE4330546A patent/DE4330546A1/en not_active Withdrawn
- 1993-09-10 SE SE9302926A patent/SE9302926L/en not_active Application Discontinuation
- 1993-09-14 AT AT185393A patent/AT402746B/en not_active IP Right Cessation
- 1993-09-14 FI FI934033A patent/FI934033A/en not_active Application Discontinuation
- 1993-09-16 JP JP23052293A patent/JPH06207397A/en active Pending
- 1993-09-16 CA CA 2106355 patent/CA2106355A1/en not_active Abandoned
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5552021A (en) * | 1993-06-17 | 1996-09-03 | Valmet Corporation | Method, device and arrangement for regulating the control of a transverse profile of a paper web in a paper machine |
| US6027612A (en) * | 1996-09-11 | 2000-02-22 | Voith Sulze Papiermaschinen Gmbh | Wire section and method of dewatering a fiber web in a wire section web |
| US6361657B2 (en) | 1999-11-17 | 2002-03-26 | Mcpherson Douglas R. | Twin fabric forming section blade mounting |
Also Published As
| Publication number | Publication date |
|---|---|
| ATA185393A (en) | 1996-12-15 |
| DE9212448U1 (en) | 1992-11-05 |
| FI934033A0 (en) | 1993-09-14 |
| DE4330546A1 (en) | 1994-03-17 |
| DE4238885A1 (en) | 1994-03-17 |
| SE9302926L (en) | 1994-03-17 |
| AT402746B (en) | 1997-08-25 |
| JPH06207397A (en) | 1994-07-26 |
| FI934033A (en) | 1994-03-17 |
| SE9302926D0 (en) | 1993-09-10 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FZDE | Discontinued | ||
| FZDE | Discontinued |
Effective date: 19990916 |