CA1165606A - Double sieve papermaking machine - Google Patents
Double sieve papermaking machineInfo
- Publication number
- CA1165606A CA1165606A CA000390622A CA390622A CA1165606A CA 1165606 A CA1165606 A CA 1165606A CA 000390622 A CA000390622 A CA 000390622A CA 390622 A CA390622 A CA 390622A CA 1165606 A CA1165606 A CA 1165606A
- Authority
- CA
- Canada
- Prior art keywords
- wire
- dewatering
- cylinder
- papermaking machine
- sieve
- 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.)
- Expired
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
- D21F1/60—Cylinder moulds
-
- 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
6886 CAN INVENTORS: ALFRED BUBIK and SIEGFRIED REUTTER
INVENTION: DOUBLE SIEVE PAPERMAKING MACHINE
ABSTRACT OF THE DISCLOSURE
A double sieve or twin-wire papermaking machine con-tains a dewatering cylinder with an open surface which is pervious for water. Below the pervious or foraminous surface of the cylinder there is arranged in spaced relationship there-from a closed cylinder wall. There is provided a dewatering path formed by the outer wire or sieve and arranged forwardly of the dewatering cylinder. The dewatering path is equipped with a dewatering device, such as for instance a foil or suction box. Arranged after the dewatering cylinder is a wire or sieve separation roll which is located internally of the inner wire, After the wire separation roll there can be arranged a suction roll. Between the wire separation roll and the suction roll there can be arranged further dewatering devices.
INVENTION: DOUBLE SIEVE PAPERMAKING MACHINE
ABSTRACT OF THE DISCLOSURE
A double sieve or twin-wire papermaking machine con-tains a dewatering cylinder with an open surface which is pervious for water. Below the pervious or foraminous surface of the cylinder there is arranged in spaced relationship there-from a closed cylinder wall. There is provided a dewatering path formed by the outer wire or sieve and arranged forwardly of the dewatering cylinder. The dewatering path is equipped with a dewatering device, such as for instance a foil or suction box. Arranged after the dewatering cylinder is a wire or sieve separation roll which is located internally of the inner wire, After the wire separation roll there can be arranged a suction roll. Between the wire separation roll and the suction roll there can be arranged further dewatering devices.
Description
BACK~ROUND OF THE INVENTION
The present invention broadly relates to the paper-making art and, more specifically, concerns a new and improved construction of a double sieve or filter papermaking machine, also referred to in the art as a twin-wire papermaking machine.
Generally speaking, the double sieve or twin-wire papermaking machine is of the type comprising a dewatering cylinder wherein along a portion of its circumference there is wrapped thereabout a first inner wire or sieve band or belt which, at least at the region of the dewatering cylinder, is surrounded by a second wire or sieve band or belt. The second wire or sieve band forms below the dewatering cylinder for-wardly of such cylinder, viewed with respect to the direction of movement of -the wires or sieve bands, a dewaterlng pa-th to which there is infed the stoak suspension by a headboX. The stock suspension serves for the fabrication o~ paper.
Such type of papermaking machine is generally known to the art specifically from Figure 3 of United States Patent No. 3,201,305.
~ith the prior art papermaking machine the dewatering cylinder possesses a completely open surface through which there can penetrate without hindrance the sieved or filtered water
The present invention broadly relates to the paper-making art and, more specifically, concerns a new and improved construction of a double sieve or filter papermaking machine, also referred to in the art as a twin-wire papermaking machine.
Generally speaking, the double sieve or twin-wire papermaking machine is of the type comprising a dewatering cylinder wherein along a portion of its circumference there is wrapped thereabout a first inner wire or sieve band or belt which, at least at the region of the dewatering cylinder, is surrounded by a second wire or sieve band or belt. The second wire or sieve band forms below the dewatering cylinder for-wardly of such cylinder, viewed with respect to the direction of movement of -the wires or sieve bands, a dewaterlng pa-th to which there is infed the stoak suspension by a headboX. The stock suspension serves for the fabrication o~ paper.
Such type of papermaking machine is generally known to the art specifically from Figure 3 of United States Patent No. 3,201,305.
~ith the prior art papermaking machine the dewatering cylinder possesses a completely open surface through which there can penetrate without hindrance the sieved or filtered water
- 2 - ~
which is expressed out of the formed paper web into the in-terior of the dewatering cylinder. However, it is unavoidable that such penetrated water can impair the web formation at other locations of the dewatering cylinder. On the other hand, there is provided forwardly of the dewatering c~linder a de-watering path which should be freely movable and at which there should be augmented the dewatering action by a fluttering of the wire of sieve band at such location. Because of difficul-ties which have arisen with this prior art proposal of papermak-ing machine, such seemingly advantageous type of papermakingmachine has not found any widespread use or acceptance in actual practice.
SUMMARY OF THE INVENTION
Therefore, with the foregotny in mind it is a primary object of the present invention to provide a new and imp~oved construction of a double sieve or twin~wire paperrna]cing rnachine with is not assoc:lated with the a~orementioned drawbacks and limitations of the prior ar-t proposals.
Another and more specific object of the present invention aims at providing a simple construction of papermaking machine working in accordance with the aforementioned prior art principle and which, however, is suitable for use in practical applications, and which in particular possesses an increased dewatering capacity, with lower energy xequirements, than similar heretofore known papermaking machines~
Now in order to implement these and still further .
objects of the inven-ti.on, which will become more readily apparent as the description proceeds, the papermakiny machine of the present development is manifested by the features that the dewatering cylinder is constituted by a cylinder having an open surface which is pervio~s to water. Below the sur-face of the cylinder there is arranged in spaced relationship therefrom a closed cylinder wall in a manner such that ~ -between the pervious or foraminous surface and the cylinder wall there is formed a receiving chamber for the sieved or filtered water, and the dewatering path is equipped with at least one dewatering device.
In this connection attention is directcd to Figure 1 of United States Patent ~o. 3,565,'~57 which dlsc:loses a double sieve or twin-wire papermaking machine wherein a dewatering cylinder is wrapped by two wires or ~elts in a similar fashion.
With this prior art machine the dewatering cylinder however is constituted by a cylinder having a solid closed surface, so that by virtue of thi.s design there only can be approximately realized one-half of the dewatering capacity owing to the one-sided dewatering action. Additionally, there is absent any dewatering path forwardly of the cylinder, so that the dewatering ~ ~S6~
capacity of the papermaking machine is still ~ur~her reduced.
Finally, in Figure 5 of United States Patent No.
4,209,360 there is disclosed to the art a double sieve or twin-wire papermaking machine which utilizes a dewatering cylinder having an open, outer surface which is formed by a wire or sieve which is shrunk-fitted thereon. The wire is supported upon circumferential grooves which form a re-ceiving chamber for the expressed sieved or filtered water.
With this state-of-the-art papermaking machine there is missing the pre-dewatering path, and also -the mannex of guiding the wire differs in a most disadvantageous fashion from the technique employed with the inventive papermaking machine of this development.
Preferably, the dewa-tering cylinder can have arranyed thereafter a wlre or sieve separation ro:L:L, at the swrfac~ o which there is accomplished the separat:Lon of the outer sieve band or wire from the inner sieve band or wire. This sieve or wire separation roll is located internally of the inner wire or sieve band. Through the use of this wire o$ sieve separation roll there is obtained, in contrast to the papermaking machine of the aforementioned United States Patent No. 3,201,305, an additional path which can be equipped with dewatering devices, such as for instance suction boxes. By virtue of the arrangement of the wire separation roll within the inner sieve band or wire there is obtained a low or compact structural height of the PaPermakiny machine which, for reasons of cost for the s~
machine and the building and for the structural alteration of longitudinal sieve or wire papermaking machines is favor-able.
Finally, within the inner wire or sieve band there can be arranged after the wire or sieve separation roll a suction roll~ The inner wire or sieve band is provided with additional dewatering devices between the wire or sieve separa-tion roll and the suction roll. By virtue of these measures the dewatering capacity of the papermaking machine can be further augmented with modest energy requirements.
BRIEF DESCRIPTION OF THE DR~INGS
The invention will be better understood and objects other than those set forth above, will become apparent when consideration is given to the ~ollow:lng detailed descrlption thereoE. Such description makes re:Ee:rence to the annexed drawings wherein:
Figure 1 schematically illustrates an exemplary embodiment of twin-wire or double sieve papermaking machine according to the invention;
Figure 2 is a fragmentary sectional view of the dewatering cylinder used in the arrangement of Figure 1 and shown on an enlarged scalej and ~ ~5~
Fi.gure 3 ls, a parti.al front view o~ the sur~ace of the dewatering cvlinder shown in the arrangement of Fiyure 2, looking essentially in the direction of the arrow A thereof.
DETAILE~ DESCRIPTION OF THE PREFERRED EMBODIMENTS
Describing now the drawings, it is to be understood that only enough of the construction of the twin-wire or double sieve papermaking machine has been shown in the drawings, while simplifying the illustration, as will enable those skilled in the art to readily understand the underlying principles and concep-ts of the present development. Turning attention now to Figure 1 there is illustrated therein an exemplary embodiment of papermaking machine which will be seen to contain a dewater-ing cylinder 1 about which there is wrapped or trained along a circumferential or peripheralangle ~ an inner wire or sieve 2. The inner wire or sieve 2 is guided over yuide rolls 3, a wire or sieve separation roll ~ and a suctionroll 5. Between the ~ suction roll 5 and the guide roll 3 which is arranged after the
which is expressed out of the formed paper web into the in-terior of the dewatering cylinder. However, it is unavoidable that such penetrated water can impair the web formation at other locations of the dewatering cylinder. On the other hand, there is provided forwardly of the dewatering c~linder a de-watering path which should be freely movable and at which there should be augmented the dewatering action by a fluttering of the wire of sieve band at such location. Because of difficul-ties which have arisen with this prior art proposal of papermak-ing machine, such seemingly advantageous type of papermakingmachine has not found any widespread use or acceptance in actual practice.
SUMMARY OF THE INVENTION
Therefore, with the foregotny in mind it is a primary object of the present invention to provide a new and imp~oved construction of a double sieve or twin~wire paperrna]cing rnachine with is not assoc:lated with the a~orementioned drawbacks and limitations of the prior ar-t proposals.
Another and more specific object of the present invention aims at providing a simple construction of papermaking machine working in accordance with the aforementioned prior art principle and which, however, is suitable for use in practical applications, and which in particular possesses an increased dewatering capacity, with lower energy xequirements, than similar heretofore known papermaking machines~
Now in order to implement these and still further .
objects of the inven-ti.on, which will become more readily apparent as the description proceeds, the papermakiny machine of the present development is manifested by the features that the dewatering cylinder is constituted by a cylinder having an open surface which is pervio~s to water. Below the sur-face of the cylinder there is arranged in spaced relationship therefrom a closed cylinder wall in a manner such that ~ -between the pervious or foraminous surface and the cylinder wall there is formed a receiving chamber for the sieved or filtered water, and the dewatering path is equipped with at least one dewatering device.
In this connection attention is directcd to Figure 1 of United States Patent ~o. 3,565,'~57 which dlsc:loses a double sieve or twin-wire papermaking machine wherein a dewatering cylinder is wrapped by two wires or ~elts in a similar fashion.
With this prior art machine the dewatering cylinder however is constituted by a cylinder having a solid closed surface, so that by virtue of thi.s design there only can be approximately realized one-half of the dewatering capacity owing to the one-sided dewatering action. Additionally, there is absent any dewatering path forwardly of the cylinder, so that the dewatering ~ ~S6~
capacity of the papermaking machine is still ~ur~her reduced.
Finally, in Figure 5 of United States Patent No.
4,209,360 there is disclosed to the art a double sieve or twin-wire papermaking machine which utilizes a dewatering cylinder having an open, outer surface which is formed by a wire or sieve which is shrunk-fitted thereon. The wire is supported upon circumferential grooves which form a re-ceiving chamber for the expressed sieved or filtered water.
With this state-of-the-art papermaking machine there is missing the pre-dewatering path, and also -the mannex of guiding the wire differs in a most disadvantageous fashion from the technique employed with the inventive papermaking machine of this development.
Preferably, the dewa-tering cylinder can have arranyed thereafter a wlre or sieve separation ro:L:L, at the swrfac~ o which there is accomplished the separat:Lon of the outer sieve band or wire from the inner sieve band or wire. This sieve or wire separation roll is located internally of the inner wire or sieve band. Through the use of this wire o$ sieve separation roll there is obtained, in contrast to the papermaking machine of the aforementioned United States Patent No. 3,201,305, an additional path which can be equipped with dewatering devices, such as for instance suction boxes. By virtue of the arrangement of the wire separation roll within the inner sieve band or wire there is obtained a low or compact structural height of the PaPermakiny machine which, for reasons of cost for the s~
machine and the building and for the structural alteration of longitudinal sieve or wire papermaking machines is favor-able.
Finally, within the inner wire or sieve band there can be arranged after the wire or sieve separation roll a suction roll~ The inner wire or sieve band is provided with additional dewatering devices between the wire or sieve separa-tion roll and the suction roll. By virtue of these measures the dewatering capacity of the papermaking machine can be further augmented with modest energy requirements.
BRIEF DESCRIPTION OF THE DR~INGS
The invention will be better understood and objects other than those set forth above, will become apparent when consideration is given to the ~ollow:lng detailed descrlption thereoE. Such description makes re:Ee:rence to the annexed drawings wherein:
Figure 1 schematically illustrates an exemplary embodiment of twin-wire or double sieve papermaking machine according to the invention;
Figure 2 is a fragmentary sectional view of the dewatering cylinder used in the arrangement of Figure 1 and shown on an enlarged scalej and ~ ~5~
Fi.gure 3 ls, a parti.al front view o~ the sur~ace of the dewatering cvlinder shown in the arrangement of Fiyure 2, looking essentially in the direction of the arrow A thereof.
DETAILE~ DESCRIPTION OF THE PREFERRED EMBODIMENTS
Describing now the drawings, it is to be understood that only enough of the construction of the twin-wire or double sieve papermaking machine has been shown in the drawings, while simplifying the illustration, as will enable those skilled in the art to readily understand the underlying principles and concep-ts of the present development. Turning attention now to Figure 1 there is illustrated therein an exemplary embodiment of papermaking machine which will be seen to contain a dewater-ing cylinder 1 about which there is wrapped or trained along a circumferential or peripheralangle ~ an inner wire or sieve 2. The inner wire or sieve 2 is guided over yuide rolls 3, a wire or sieve separation roll ~ and a suctionroll 5. Between the ~ suction roll 5 and the guide roll 3 which is arranged after the
3", '` Y~ 99 suctionJs, viewed with respect to the direction of movement B
of the wire or sieve 2, there is arranged in known manner a take-off or removal roll 6 containing a felt band 7 or equivalent structure.
Additionally, the papermaking machine shown in Figure 1 is equipped with a second wire or sieve 101 the so-called outer wire or sieve. This second wire 1.0, viewed with respect to its v ~
direction of movernent B, forms a dewatering path or rwn E or~
wardly of the dewatering cylinder l. Following the location of the dewatering path E this second wire or sieve 10 wraps in conjunction with the inner wire ~r sieve 2 about the dewatering cylinder l along a circumferential or peripheral angle a.
This second or outer wire or sieve 10 together wi-th the inner wire sieve 2 extends conjointly up to the region of the wire or sieve separation roll 4 where there is accomplished the separation of both wires or sieves 2 and lO from one ano-ther.
For this purpose the outer wire or sieve 10 is guided over guide rolls 11.
A conventionally constructed headbox 12 serves to infeed the stock suspension needed for the paper fabrication to the dewatering path E. This dewatering path or run ~., in turn, is equipped wi-th a dewatering device 13 which contains dewatering ledges or strips 1~, typically :Eor instance Eoils or the like, or else can be constructed as a suction box. ~l.so, suction boxes 15 and 16 o.r equivalent expedients can be arranged between the dewatering cylinder 1 and the wire or sieve separa-tion roll 4 as well as between the wire separation roll ~ andthe suction roll 5.
Additionally, and as will be seen by reverting -to Figure l the twin-wire papermaking machine is also equipped with catch or receiving contairers or vats 17 and 18 for receiving the sieved or filtered water which has been expressed out of the formed paper web through both of the wires 2 and 10 at the region of the dewatering cylinder 1.
This dewatering cylinder l, as best seen by referr-ing to Figure 2, is provided with a closed f solid cylinder wall 20 upon which there are arranged and secured in any suitable fashion, according to one embodiment o~ the in-vention, ribs 21 in the circumferential direction. Extend-ing tranversally to the circumferential ribs 21 there are arranged in axial direction transvers-ribs 22 upon which there can be shrunk-fitted a wire or sieve 23 or the like.
To simplify the illustration such has only been shown in Figure 2. This wire or sieve 23 forms the open surface 0 which is pervious for water and upon which there are supported both of the wires or sieves 2 and 10.
Howevex, it should be clearly understood that it is possible to dispense w:Lth the wse o~ the wire or sieve 23 and that also the dewatering cylinder l can be constructed in a different similar Eashion. What is only of importance is that between an outer cylinder surface 0, which is pervious to the water, and the inner solid cylinder wall 20 there is formed a receiving or collecting chamber 24 for the sieved or filtered water.
During opera-tion, the papermaki~g machine of the invention dewaters the fiber stock suspension which is infed by the headbox 12 initially at the wire or sieve 10 at the region of the dewatering path E by means of the dewatering device 13. Thereafter, there ~s accomplished the dewatering between both of the wires or sieves 2 and 10, and specifically, essentially towards the ou-tside and also towards the inside, and the inwardly expressed water arrives at the receiving chamber 23 of the dewatering cylinder 1 and following raising of both wires or sieves 2 and 10 from the dewatering cylinder 1 such removed water is deposi.ted into the catch or collecting container 18. After such double-sided dewatering there is accomplished a dewatering towards the other side, and specific-ally, initially by the dewatering device 15 and following the separation of -the wires or sieves 2 and 10 from one another by the action of the wire separation roll 4 by means of the dewatering devices 16.
of the wire or sieve 2, there is arranged in known manner a take-off or removal roll 6 containing a felt band 7 or equivalent structure.
Additionally, the papermaking machine shown in Figure 1 is equipped with a second wire or sieve 101 the so-called outer wire or sieve. This second wire 1.0, viewed with respect to its v ~
direction of movernent B, forms a dewatering path or rwn E or~
wardly of the dewatering cylinder l. Following the location of the dewatering path E this second wire or sieve 10 wraps in conjunction with the inner wire ~r sieve 2 about the dewatering cylinder l along a circumferential or peripheral angle a.
This second or outer wire or sieve 10 together wi-th the inner wire sieve 2 extends conjointly up to the region of the wire or sieve separation roll 4 where there is accomplished the separation of both wires or sieves 2 and lO from one ano-ther.
For this purpose the outer wire or sieve 10 is guided over guide rolls 11.
A conventionally constructed headbox 12 serves to infeed the stock suspension needed for the paper fabrication to the dewatering path E. This dewatering path or run ~., in turn, is equipped wi-th a dewatering device 13 which contains dewatering ledges or strips 1~, typically :Eor instance Eoils or the like, or else can be constructed as a suction box. ~l.so, suction boxes 15 and 16 o.r equivalent expedients can be arranged between the dewatering cylinder 1 and the wire or sieve separa-tion roll 4 as well as between the wire separation roll ~ andthe suction roll 5.
Additionally, and as will be seen by reverting -to Figure l the twin-wire papermaking machine is also equipped with catch or receiving contairers or vats 17 and 18 for receiving the sieved or filtered water which has been expressed out of the formed paper web through both of the wires 2 and 10 at the region of the dewatering cylinder 1.
This dewatering cylinder l, as best seen by referr-ing to Figure 2, is provided with a closed f solid cylinder wall 20 upon which there are arranged and secured in any suitable fashion, according to one embodiment o~ the in-vention, ribs 21 in the circumferential direction. Extend-ing tranversally to the circumferential ribs 21 there are arranged in axial direction transvers-ribs 22 upon which there can be shrunk-fitted a wire or sieve 23 or the like.
To simplify the illustration such has only been shown in Figure 2. This wire or sieve 23 forms the open surface 0 which is pervious for water and upon which there are supported both of the wires or sieves 2 and 10.
Howevex, it should be clearly understood that it is possible to dispense w:Lth the wse o~ the wire or sieve 23 and that also the dewatering cylinder l can be constructed in a different similar Eashion. What is only of importance is that between an outer cylinder surface 0, which is pervious to the water, and the inner solid cylinder wall 20 there is formed a receiving or collecting chamber 24 for the sieved or filtered water.
During opera-tion, the papermaki~g machine of the invention dewaters the fiber stock suspension which is infed by the headbox 12 initially at the wire or sieve 10 at the region of the dewatering path E by means of the dewatering device 13. Thereafter, there ~s accomplished the dewatering between both of the wires or sieves 2 and 10, and specifically, essentially towards the ou-tside and also towards the inside, and the inwardly expressed water arrives at the receiving chamber 23 of the dewatering cylinder 1 and following raising of both wires or sieves 2 and 10 from the dewatering cylinder 1 such removed water is deposi.ted into the catch or collecting container 18. After such double-sided dewatering there is accomplished a dewatering towards the other side, and specific-ally, initially by the dewatering device 15 and following the separation of -the wires or sieves 2 and 10 from one another by the action of the wire separation roll 4 by means of the dewatering devices 16.
Claims (6)
1. A twin-wire papermaking machine for forming a paper web comprising:
a dewatering cylinder;
a first inner wire which wraps about a portion of the circumference of said dewatering cylinder;
a second wire surrounding the first inner wire at least at the region of the dewatering cylinder;
the second wire defining a dewatering path extending substantially in horizontal direction below the dewatering cylinder and forwardly of said dewatering cylinder, viewed with respect to the direction of movement of the wires;
headbox means for infeeding a stock suspension used for fabricating paper to the dewatering path;
said dewatering cylinder comprising a cylinder having an open surface which is pervious to water;
a closed cylinder wall located radially inwardly of and below said pervious surface of said cylinder in a manner such that there is formed a receiving chamber for the sieved water between the pervious surface of the cylinder and said closed cylinder wall; and at least one dewatering device provided for said dewatering path.
a dewatering cylinder;
a first inner wire which wraps about a portion of the circumference of said dewatering cylinder;
a second wire surrounding the first inner wire at least at the region of the dewatering cylinder;
the second wire defining a dewatering path extending substantially in horizontal direction below the dewatering cylinder and forwardly of said dewatering cylinder, viewed with respect to the direction of movement of the wires;
headbox means for infeeding a stock suspension used for fabricating paper to the dewatering path;
said dewatering cylinder comprising a cylinder having an open surface which is pervious to water;
a closed cylinder wall located radially inwardly of and below said pervious surface of said cylinder in a manner such that there is formed a receiving chamber for the sieved water between the pervious surface of the cylinder and said closed cylinder wall; and at least one dewatering device provided for said dewatering path.
2. The twin-wire papermaking machine as defined in claim 1, further including:
a wire separation roll arranged after said dewatering cylinder;
said wire separation roll having a surface at which there is accomplished the separation of the second wire from the first inner wire such that the formed paper web remains at the first inner wire; and said wire separation roll being located internally of the first inner wire.
a wire separation roll arranged after said dewatering cylinder;
said wire separation roll having a surface at which there is accomplished the separation of the second wire from the first inner wire such that the formed paper web remains at the first inner wire; and said wire separation roll being located internally of the first inner wire.
3. The twin-wire papermaking machine as defined in claim 1 or 2, further including:
a suction roll arranged within the first inner wire following the wire separation roll; and additional dewatering devices provided for said first inner wire between the wire separation roll and the suction roll.
a suction roll arranged within the first inner wire following the wire separation roll; and additional dewatering devices provided for said first inner wire between the wire separation roll and the suction roll.
4. The twin-wire papermaking machine as defined in claim 2, wherein:
said wire separation roll acting upon said inner wire such that said inner wire runs-off the dewatering cylinder with at most a slight inclination and extends in a direction opposite to the direction of infeed of the stock suspension by said headbox means to said dewatering path.
said wire separation roll acting upon said inner wire such that said inner wire runs-off the dewatering cylinder with at most a slight inclination and extends in a direction opposite to the direction of infeed of the stock suspension by said headbox means to said dewatering path.
5. The twin-wire papermaking machine as defined in claim 4, further including:
water catch means arranged between said dewatering cylinder and said wire separation roll for receiving water expressed out of the formed paper web; and said dewatering cylinder containing rib members extending in the lengthwise direction of said dewatering cylinder above said closed cylinder wall and serving to propel water expressed from the formed paper web in the direction of said water catch means.
water catch means arranged between said dewatering cylinder and said wire separation roll for receiving water expressed out of the formed paper web; and said dewatering cylinder containing rib members extending in the lengthwise direction of said dewatering cylinder above said closed cylinder wall and serving to propel water expressed from the formed paper web in the direction of said water catch means.
6. The twin-wire papermaking machine as defined in claim 1, wherein:
said dewatering cylinder is devoid of any further rolls at the immediate vicinity thereof, either beneath or above said dewatering cylinder.
said dewatering cylinder is devoid of any further rolls at the immediate vicinity thereof, either beneath or above said dewatering cylinder.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CH939180 | 1980-12-19 | ||
| CH9391/80-3 | 1980-12-19 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1165606A true CA1165606A (en) | 1984-04-17 |
Family
ID=4351500
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000390622A Expired CA1165606A (en) | 1980-12-19 | 1981-11-20 | Double sieve papermaking machine |
Country Status (5)
| Country | Link |
|---|---|
| JP (1) | JPS57128291A (en) |
| CA (1) | CA1165606A (en) |
| DE (1) | DE3102496A1 (en) |
| FI (1) | FI813435L (en) |
| IT (1) | IT1140095B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FI91788C (en) * | 1990-09-12 | 1994-08-10 | Valmet Paper Machinery Inc | Path forming section with double wire in a paper machine |
| US6203666B1 (en) * | 1997-09-09 | 2001-03-20 | Tokushu Paper Mfg. Co., Ltd. | Method and device for paper web manufacturing |
-
1981
- 1981-01-27 DE DE19813102496 patent/DE3102496A1/en not_active Withdrawn
- 1981-11-02 FI FI813435A patent/FI813435L/en not_active Application Discontinuation
- 1981-11-20 CA CA000390622A patent/CA1165606A/en not_active Expired
- 1981-12-10 IT IT25503/81A patent/IT1140095B/en active
- 1981-12-18 JP JP56205049A patent/JPS57128291A/en active Pending
Also Published As
| Publication number | Publication date |
|---|---|
| JPS57128291A (en) | 1982-08-09 |
| IT8125503A0 (en) | 1981-12-10 |
| IT1140095B (en) | 1986-09-24 |
| DE3102496A1 (en) | 1982-08-12 |
| FI813435L (en) | 1982-06-20 |
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