EP0712454B1 - Gap former in a paper machine - Google Patents
Gap former in a paper machine Download PDFInfo
- Publication number
- EP0712454B1 EP0712454B1 EP95920084A EP95920084A EP0712454B1 EP 0712454 B1 EP0712454 B1 EP 0712454B1 EP 95920084 A EP95920084 A EP 95920084A EP 95920084 A EP95920084 A EP 95920084A EP 0712454 B1 EP0712454 B1 EP 0712454B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- forming
- rib
- wire
- roll
- gap
- 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 - Lifetime
Links
Images
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
-
- 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
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21F—PAPER-MAKING MACHINES; METHODS OF PRODUCING PAPER THEREON
- D21F11/00—Processes for making continuous lengths of paper, or of cardboard, or of wet web for fibre board production, on paper-making machines
Definitions
- the invention concerns a gap former in a paper machine, comprising a twin-wire zone, according to the pre-characterizing clause of claim 1.
- the pulp suspension is passed from the headbox into a gap formed by a forming roll and by two wires, after which gap the two wires and the pulp layer placed between them follow the curve form of the forming roll, most of the water being drained through the wires.
- the necessary dewatering pressure is produced by means of the tension of the outer wire, which tension produces a pressure in the pulp layer, which pressure is proportional to the wire tension and inversely proportional to the curve radius of the forming roll.
- part of the kinetic energy of the pulp jet is converted to pressure energy, and the jet speed is lowered accordingly.
- the dewatering through the outer wire away from the forming roll is intensified by the centrifugal force. Dewatering towards the forming roll can be intensified by means of negative pressure in a zone of the forming roll.
- the gap former according to the present invention is characterized in that the free run of the forming wires from the forming roll to the first forming rib is substantially little and less than 200 mm and in that the first forming rib of the forming shoe or a forming-rib construction composed of two or more interconnected forming ribs, which are the first forming ribs of the forming shoe, is mounted resiliently and is loaded adjustably.
- the principal idea of the invention i.e. that the first or the first two forming ribs are mounted on the former resiliently, provides the significant advantage that said forming, rib (or ribs) can be brought very close to the forming roll, even so that the first forming rib can be placed facing the forming roll, in which case there is no free distance between the forming roll and the first forming rib. This improves the stability of the wires and the runnability of the former in different running situations to a substantial extent.
- first forming, rib is mounted resiliently, it is also loaded adjustably, thereby permiting running with a number of grammages, thicknesses, etc.
- first forming, rib is mounted resiliently in accordance with the present invention, if is placed automatically in the correct position when the layer thickness is changed.
- the solution in accordance with the present invention is particularly usable for different grades of fine paper.
- the deflector rib of the MB-unit can be placed facing the resilient ribbed forming, shoe to improve the draining. In such a case, the deflector rib does not have to be loaded or adjustable, but it may be stationary.
- Figure 1 is a schematic side view of a gap former in accordance with the invention.
- Figure 2 shows an enlarged detail of the gap former as shown in Fig. 1 from the area of the forming roll, and a forming-rib construction.
- Figure 3 is a schematic sectional view of the installation of the resilient forming rib in relation to the forming roll.
- the former shown in Fig. 1 is a so-called gap former, in which the slice part 31 of the headbox 30 feeds a pulp suspension jet into the forming gap G between the forming wires 10,20.
- the geometry of said forming gap G is determined from above by the forming roll 11 and from below by the breast roll 21, which guides the second forming wire 20, i.e., in the illustration in Fig. 1, the lower wire.
- the forming roll 11 is followed by the MB-unit 40.
- the breast roll 21 has been arranged so that its position can be regulated in the direction of the arrow E, i.e., in the exemplifying embodiment shown in Fig. 1, substantially in the vertical direction.
- the geometry of the forming gap G is preferably such that, on the forming roll 11, the forming wires 10.20 have a common curve sector ⁇ .
- the first forming wire 10 has been formed into a wire loop by means of the forming roll 11 and the guide rolls 14, and, as was already stated above, inside said loop of the first forming wire 10, the MB-unit 40 is fitted.
- the MB-unit 40 comprises two draining chambers 41,42, in which a vacuum has been arranged to be effective.
- Each draining chamber 41,42 is provided with a drain duct 43,44, through which the water that has been passed into the draining chamber 41,42 with the aid of said vacuum is drained away from the draining chamber.
- the water enters along the deflector duct 12,13.
- the deflector rib 12a As is shown in connection with the first deflector duct 12. at the lower end of said deflector duct 12, there is a deflector rib 12a placed against the first forming wire 10.
- the deflector rib 12a defines said deflector duct 12, and the water, which is guided by the deflector rib 12a, is drained through the first forming wire 10 along the first deflector duct 12 into the first draining chamber 41.
- the second forming wire 20 has been formed into a wire loop by means of the breast roll 21 and the guide rolls 21a.
- a first forming rib 22a of a forming shoe is arranged, which is placed against the second forming wire 20 and which is followed by a number of forming ribs 23, which are placed at a distance from one another and which have been arranged as a set of ribs or as a ribbed deck.
- the set of ribs or the ribbed deck has been integrated as a common box 24, which can be subjected to a vacuum if necessary, by means of which vacuum the draining through the second forming wire 20 is intensified.
- the first set of ribs or the ribbed deck is substantially straight or slightly curved.
- a second set or ribs 25 or an equivalent ribbed deck which is fitted inside the loop of the second forming wire 20 and which has been integrated similarly as a box 26.
- the open ribbed deck of the second set of ribs 25 has been formed as curved so that, owing to this curve form, a compression is applied to the stock web running between the wires 10,20. whereby this compression, together with the centrifugal force produced by the curve form of the ribbed deck 25, produces draining of water out of the stock web through the first forming wire 10.
- This water that has been drained out of the stock is passed along the second deflector duct 13 into the second draining chamber 42, being aided by a vacuum that is preferably effective in said chamber 42.
- the draining is intensified and promoted further by the deflector rib (not shown) placed in the lower part of the second deflector duct 13.
- suction boxes 27 are provided with a ribbed deck and by whose means draining of water out of the stock web through the second forming wire 20 is produced, and by means of which suction boxes 27 it is achieved at the same time that the stock web follows along with the second forming wire 20 as the runs of the wires 10,20 are separated from one another.
- the suction boxes 27 there follows the second forming roll 28, which is provided with a suction zone 29 for further removal of water out of the stock web and so as to guarantee that the stock web remains on the second forming wire 20.
- Fig. 2 shows an enlarged detail of the former as shown in Fig. 1 from the area of the forming gap G and of a forming-rib construction 22.
- the forming-rib construction 22 comprises the first forming rib 22a and a successive second forming rib 22b which are interconnected by means of a fastening member 22c.
- This forming-rib construction 22 is supported on the frame 22d of the former or the box 24 by means of adjustable loading members, preferably loading hoses 22e, so that, by feeding a pressure medium into these loading hoses 22e in the desired way, the forming-rib construction 22 can be made to be positioned in the desired position in relation to the wires 10,20 and to the forming roll 11.
- the installation of the forming-rib construction 22 is resilient, in which case the ribs 22a,22b are placed automatically in the correct position if, for example, the thickness of the pulp suspension layer fed into the forming gap G is changed.
- the pressure of the pressure medium in the loading hoses 22e can be regulated even during running. Besides the possibility of regulating the pressure of the ribs against the second forming wire 20 by means of the loading hoses 22e, by means of said loading hoses 22e it is also possible to regulate the angle of the ribs 22a,22b in relation to the forming wire 20.
- the forming rib 22a in accordance with the invention can be placed fully facing the forming roll 11, in which case there is no such free distance a at all.
- the elimination of this free distance improves the stability of the wires 10,20 and the runnability of the former in different running situations essentially.
- the free run from the forming roll 11 to the first forming rib 22a is preferably in the range of 0...70 mm.
- Such an adjustable, and resilient installation is particularly favourable when grades of fine paper are run, in which case the common curve sector ⁇ of the wires 10,20 on the forming roll 11 is very little and the streaks occurring in the fibre stock are more common than in cases in which a larger curve sector ⁇ is used.
- the forming-rib construction 22 whose position can be adjusted can be pulled apart from the forming wire 20 when the machine is being started or run down. Also otherwise, if necessary, the forming-rib construction 22 can be pulled apart from the wire 20.
Landscapes
- Paper (AREA)
- Diaphragms For Electromechanical Transducers (AREA)
- Making Paper Articles (AREA)
- Folding Of Thin Sheet-Like Materials, Special Discharging Devices, And Others (AREA)
Abstract
Description
Claims (9)
- A gap former in a paper machine, comprising a twin-wire zone, which is composed of a loop of a first forming wire (10) and of a loop of a second forming wire (20) and which starts from a forming gap (G), into which a slice part (31) of a headbox (30) feeds a pulp suspension jet, and which forming gap (G) is defined, from one side, by the first forming wire (10), which runs over a forming roll (11), and, from the opposite side, by a substantially straight run of the second forming wire (20) extending from a breast roll (21) to the forming roll (11), draining equipment (40...44) being fitted inside the loop of the first forming wire (10) downstream of the forming roll (11), which draining equipment is provided with a deflector duct (12) and with a deflector rib (12a) placed against the first forming wire (10) at the lower part of said deflector duct (12), and a forming shoe being arranged inside the loop of the second wire (20), which forming shoe is provided with a ribbed deck consisting of forming ribs (22a, 22b, 23) and which is loaded against the second forming wire (20), characterized in that the free run of the forming wires (10, 20) from the forming roll (11) to the first forming rib (22a) of the forming shoe is substantially little and less than 200 mm and in that the first forming rib (22a) or a forming-rib construction (22) composed of two or more interconnected forming ribs (22a, 22b), which are the first forming ribs of the forming shoe, is mounted resiliently and is loaded adjustably.
- A gap former as claimed in claim 1, characterized in that the first forming rib (22a) or the forming-rib construction (22) is mounted so that said forming rib (22a) or forming-rib construction (22) can be pulled apart from the second forming wire (20).
- A gap former as claimed in claim 1 or 2, characterized in that the first forming rib (22a) is mounted, in the running direction of the forming wires (10,20), substantially at the point at which the forming wires (10,20) depart from the forming roll (11) at the end of their common curve sector (α).
- A gap former as claimed in claim 1 or 2, characterized in that the first forming rib (22a) or the forming-rib construction (22) is mounted substantially facing the deflector rib (12a), which is placed directly after the forming roll (11).
- A gap former as claimed in any of the preceding claims, characterized in that the first forming rib (22a) or the forming-rib construction (22) is loaded against the second forming wire (20) by means of pressure-medium operated loading members, such as loading hoses (22e).
- A gap former as claimed in claim 5, characterized in that the first forming rib (22a) or the forming-rib construction (22) is loaded resiliently by means of a pneumatic pressure medium.
- A gap former as claimed in claim 6, characterized in that the first forming rib (22a) or the forming-rib construction (22) is loaded pneumatically so that said forming rib (22a) or the forming-rib construction (22) is fitted to be positioned automatically in accordance with the thickness of the layer of fibrous pulp.
- A gap former as claimed in any of the preceding claims, characterized in that the run of the forming wires (10,20) from the forming roll (11) to the first forming rib (22a) is substantially nil.
- A gap former as claimed in any of the claims 1 to 7, characterized in that the run of the forming wires (10,20) from the forming roll (11) to the first forming rib (22a) is in the range of 0...70 mm.
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FI942832A FI112509B (en) | 1994-06-15 | 1994-06-15 | Paper machine other formers |
FI942832 | 1994-06-15 | ||
PCT/FI1995/000276 WO1995034713A1 (en) | 1994-06-15 | 1995-05-22 | Gap former in a paper machine |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0712454A1 EP0712454A1 (en) | 1996-05-22 |
EP0712454B1 true EP0712454B1 (en) | 2001-10-17 |
Family
ID=8540921
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP95920084A Expired - Lifetime EP0712454B1 (en) | 1994-06-15 | 1995-05-22 | Gap former in a paper machine |
Country Status (8)
Country | Link |
---|---|
EP (1) | EP0712454B1 (en) |
JP (1) | JP3828148B2 (en) |
KR (1) | KR100356281B1 (en) |
AT (1) | ATE207154T1 (en) |
CA (1) | CA2168119C (en) |
DE (1) | DE69523257T2 (en) |
FI (1) | FI112509B (en) |
WO (1) | WO1995034713A1 (en) |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE19828237A1 (en) | 1998-06-25 | 1999-12-30 | Voith Sulzer Papiertech Patent | Double-fourdrinier section at a papermaking machine |
DE10327425A1 (en) * | 2003-06-18 | 2005-01-05 | Voith Paper Patent Gmbh | Twin-wire former of a machine for producing a fibrous web |
EP3260802B1 (en) * | 2016-06-23 | 2019-10-09 | Valmet Technologies Oy | Nozzle for a device for contact-free treatment of a running fiber web |
KR102236703B1 (en) * | 2020-07-17 | 2021-04-06 | 주식회사 아진피앤피 | sheet forming section structure of papermaking processing equipment |
Family Cites Families (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE4002304A1 (en) * | 1990-01-26 | 1991-08-14 | Escher Wyss Gmbh | Paper forming stretch |
DE4026953C2 (en) * | 1990-01-26 | 1995-11-30 | Escher Wyss Gmbh | Dewatering device and method for dewatering on a twin wire former |
-
1994
- 1994-06-15 FI FI942832A patent/FI112509B/en active
-
1995
- 1995-05-22 KR KR1019960700771A patent/KR100356281B1/en not_active IP Right Cessation
- 1995-05-22 JP JP50168396A patent/JP3828148B2/en not_active Expired - Fee Related
- 1995-05-22 AT AT95920084T patent/ATE207154T1/en active
- 1995-05-22 DE DE69523257T patent/DE69523257T2/en not_active Expired - Lifetime
- 1995-05-22 EP EP95920084A patent/EP0712454B1/en not_active Expired - Lifetime
- 1995-05-22 WO PCT/FI1995/000276 patent/WO1995034713A1/en active IP Right Grant
- 1995-05-22 CA CA002168119A patent/CA2168119C/en not_active Expired - Fee Related
Also Published As
Publication number | Publication date |
---|---|
WO1995034713A1 (en) | 1995-12-21 |
FI942832A (en) | 1995-12-16 |
FI942832A0 (en) | 1994-06-15 |
CA2168119A1 (en) | 1995-12-21 |
FI112509B (en) | 2003-12-15 |
EP0712454A1 (en) | 1996-05-22 |
KR100356281B1 (en) | 2003-02-11 |
ATE207154T1 (en) | 2001-11-15 |
CA2168119C (en) | 2007-03-27 |
JP3828148B2 (en) | 2006-10-04 |
DE69523257T2 (en) | 2002-06-27 |
JPH09504060A (en) | 1997-04-22 |
DE69523257D1 (en) | 2001-11-22 |
KR960704112A (en) | 1996-08-31 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
EP1543194B1 (en) | Forming of a paper or board web in a twin-wire former | |
US5074964A (en) | Web forming apparatus having a double wire section | |
CA1176492A (en) | Twin-wire paper machine and method of opertion | |
US5536372A (en) | Web former for a paper machine with spring blade loading device | |
EP0373133A2 (en) | Method and device in the formation of a paper or board web | |
EP0371786A2 (en) | Web forming method and apparatus | |
EP0296135B1 (en) | Hydrid former for a paper machine | |
US5599427A (en) | Twin-wire web former in a paper machine | |
US5074966A (en) | Gap former in a paper machine | |
CA2336341A1 (en) | Former-press section in a paper machine and method for transfer of the web from the former to the press section | |
EP0699798B1 (en) | Twin-wire former, in particular for high-speed paper machines | |
EP0160615A2 (en) | Top wire former | |
EP0712454B1 (en) | Gap former in a paper machine | |
CA2151645C (en) | Hybrid former for a paper machine | |
US4919760A (en) | Web former for a paper machine | |
US4923568A (en) | Dewatering zone in a papermachine | |
EP0865532B1 (en) | Method and arrangement in a web former for preventing rewetting of a web | |
EP0627524B1 (en) | Web former in a paper machine | |
US5759353A (en) | Web former in a paper machine | |
US5573643A (en) | Twin wire web former in a paper machine | |
US7300553B2 (en) | Arrangement for a wire section of a paper or board machine | |
EP1137844B1 (en) | Twin-wire former | |
WO1999060205A1 (en) | Twin-wire roll-gap former in a paper machine | |
GB2063948A (en) | Paper-making machines | |
GB1378055A (en) | Paper forming apparatus |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
AK | Designated contracting states |
Kind code of ref document: A1 Designated state(s): AT DE FR GB IT SE |
|
17P | Request for examination filed |
Effective date: 19960605 |
|
17Q | First examination report despatched |
Effective date: 19980616 |
|
RTI1 | Title (correction) |
Free format text: GAP FORMER IN A PAPER MACHINE |
|
GRAG | Despatch of communication of intention to grant |
Free format text: ORIGINAL CODE: EPIDOS AGRA |
|
GRAG | Despatch of communication of intention to grant |
Free format text: ORIGINAL CODE: EPIDOS AGRA |
|
GRAH | Despatch of communication of intention to grant a patent |
Free format text: ORIGINAL CODE: EPIDOS IGRA |
|
GRAH | Despatch of communication of intention to grant a patent |
Free format text: ORIGINAL CODE: EPIDOS IGRA |
|
RAP1 | Party data changed (applicant data changed or rights of an application transferred) |
Owner name: VALMET CORPORATION(REG.NO.763281) |
|
RAP1 | Party data changed (applicant data changed or rights of an application transferred) |
Owner name: METSO PAPER, INC.(REG.NO. 763281) |
|
GRAA | (expected) grant |
Free format text: ORIGINAL CODE: 0009210 |
|
AK | Designated contracting states |
Kind code of ref document: B1 Designated state(s): AT DE FR GB IT SE |
|
REF | Corresponds to: |
Ref document number: 207154 Country of ref document: AT Date of ref document: 20011115 Kind code of ref document: T |
|
REF | Corresponds to: |
Ref document number: 69523257 Country of ref document: DE Date of ref document: 20011122 |
|
REG | Reference to a national code |
Ref country code: GB Ref legal event code: IF02 |
|
ET | Fr: translation filed | ||
PLBE | No opposition filed within time limit |
Free format text: ORIGINAL CODE: 0009261 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT |
|
26N | No opposition filed | ||
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: FR Payment date: 20100611 Year of fee payment: 16 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: IT Payment date: 20100522 Year of fee payment: 16 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: SE Payment date: 20100517 Year of fee payment: 16 Ref country code: GB Payment date: 20100519 Year of fee payment: 16 |
|
REG | Reference to a national code |
Ref country code: SE Ref legal event code: EUG |
|
GBPC | Gb: european patent ceased through non-payment of renewal fee |
Effective date: 20110522 |
|
REG | Reference to a national code |
Ref country code: FR Ref legal event code: ST Effective date: 20120131 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: IT Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20110522 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: FR Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20110531 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: GB Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20110522 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: AT Payment date: 20120511 Year of fee payment: 18 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: SE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20110523 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: DE Payment date: 20130522 Year of fee payment: 19 |
|
REG | Reference to a national code |
Ref country code: AT Ref legal event code: MM01 Ref document number: 207154 Country of ref document: AT Kind code of ref document: T Effective date: 20130531 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: AT Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20130531 |
|
REG | Reference to a national code |
Ref country code: DE Ref legal event code: R119 Ref document number: 69523257 Country of ref document: DE |
|
REG | Reference to a national code |
Ref country code: DE Ref legal event code: R119 Ref document number: 69523257 Country of ref document: DE Effective date: 20141202 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: DE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20141202 |