FI90443C

FI90443C - Method and apparatus for controlling the vacuum plane of a dewatering element in a paper machine

Info

Publication number: FI90443C
Application number: FI912202A
Authority: FI
Inventors: Jaakko Kirjasniemi; Antti Suonperae
Original assignee: Valmet Paper Machinery Inc
Priority date: 1991-05-07
Filing date: 1991-05-07
Publication date: 1994-02-10
Also published as: FI912202A; FI90443B; FI912202A0

Description

9044390443

Menetelmå ja laite tyhjdtason sååtåmiseksi paperikoneen vedenpoistoelementisså Forfarande och anordning for regiering 5 av vakuumplanet i ett awattningselement i en pappersmaskin 10 Keksinnon kohteena on menetelmå ja laite tyhjotason saåtåmiseksi paperikoneen vedenpoistoelementisså.The invention relates to a method and an apparatus for obtaining a vacuum level in a dewatering element of a paper machine. The invention relates to a method and an apparatus for obtaining a vacuum level in a dewatering element of a paper machine.

Paperikoneen viiraosalla on kåytetty vedenpoistoelementtejå, joissa tyhjdtasoa ja veden poistumista yllåpidetåån nestepatsaan muodostaman 15 ns. imujalan avulla. Nåitå vedenpoistoelementtejå ovat nykyisin mm.Dewatering elements have been used on the wire part of the paper machine, in which the vacuum level and the drainage of water are maintained by the 15 ns. by means of a suction foot. These dewatering elements currently include e.g.

imufoililaatikot ja listakengåt. Tarvittava nestepatsaan korkeus syntyy foililaatikossa olevan pinnan ja imujalan alapååsså olevan vesilukko-osan pinnan vålisestå korkeuserosta. Imujalkaosana voi toimia joko tasaisesti koneen poikkileveydelle sijoitetut putket tai koneen poikki 20 yltåvå yhtenainen pystykanava.suction foil boxes and moldings. The required height of the liquid column is created by the height difference between the surface in the foil box and the surface of the water trap section at the lower end of the suction foot. The suction foot section can be either pipes evenly spaced across the cross-section of the machine or a uniform vertical channel 20 across the machine.

Teoriassa tållaisen vedenpoistoelementin enimmåistyhjdtaso on viiran alapinnan ja vesilukko-osan nestepinnan vålistå nestepatsasta vastaava alipaine. Kuitenkin kåytånnosså viira kuljettaa mukanaan laatikkoon 25 ilmaa ja myos vuotoilmaa pååsee viiran ja laatikon vålistå alipaineen imemånå sisåån. Tålloin tehollinen pinta laatikossa asettuu nåiden tekijoiden yhteisvaikutuksen mukaiselle korkeudelle.In theory, the maximum drainage level of such a dewatering element is the vacuum corresponding to the liquid column between the lower surface of the wire and the liquid surface of the water trap part. However, in practice, the wire carries 25 air into the box and leakage air also enters the vacuum between the wire and the box. In this case, the effective surface in the box is set to a height corresponding to the combined effect of these factors.

Vedenpoistoelementtien alkupaineen muodostamisessa on tekniikan tason 30 ratkaisuissa kåytetty usein paperikoneen imujårjestelraåå tai erillistå ____ puhallinta. Kun imujalka on muodostunut, voidaan yhteys imujårjestel- måån sulkea.In the prior art solutions for generating the initial pressure of the dewatering elements, a paper machine suction system or a separate ____ fan has often been used. Once the suction foot is formed, the connection to the suction system can be closed.

Tyhjotason sååtd tekniikan tason mukaisissa laiteratkaisuissa on tyy-35 pillisesti tehty pååståmållå laatikkoon vuotoilmaa erityisesti tåtå vårten tehtyjen yhteiden kautta. Ilma sekoittuu poistuvaan veteen ja pienentåå imujalan painevaikutusta.Vacuum level control in prior art equipment solutions has typically been done by letting leaking air into the box, in particular through connections made for this purpose. The air mixes with the outgoing water and reduces the pressure effect of the suction foot.

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Kuitenkin kåytånndsså edellå mainittua menetelmåå ei ole saatu riittå-vållå tarkkuudella såådettåvåksi. Tåmå on johtunut osittain siitå, ettå ilman sekoittuminen on ollut epåtasaista. Lopputuloksena on usein ollut tilanne, jossa ei ole pååsty lainkaan haluttuihin tyhjotasoihin.However, in practice, the above-mentioned method has not been made adjustable with sufficient accuracy. This is partly due to the uneven mixing of the air. The end result has often been a situation in which the desired vacuum levels have not been reached at all.

5 Tåsså hakemuksessa onkin pyritty loytåmåån ratkaisu edellå mainittuun såådettåvyysongelmaan. Keksinnosså on oivallettu sååtåå tyhjdtasoa itse imujalan nesteeseen vaikuttamalla. Imujalan tyhjdlaatikossa olevan nes-tepinnan tasoon on vaikutettu vaikuttamalla imujalan alapuoliseen ns.5 This application therefore seeks to find a solution to the aforementioned problem of controllability. The invention has been found to control the vacuum level by acting on the liquid of the suction foot itself. The level of the liquid surface in the empty box of the suction foot has been affected by affecting the so-called

10 vesilukko-osan nestepinnan tasoon. Keksinnon erååsså suoritusmuodossa on imujalkaosaan kytketty joustavat letkut, joiden kautta poistovesi viedåån pois ja joiden korkeusasema on såådettåvisså. Nåiden joustavien virtausteiden toiset pååt on kytketty esim. levyyn, jonka korkeusasemaa voidaan sååtåå. Siten ulosvirtausaukon korkeutta laatikon suhteen voi-15 daan sååtåå ja siten voidaan sååtaa imujalan ylåpuolisen nestepinta- tason ja alapuolisen nestepintatason valistå korkeuseroa, joka on olen-nainen sååtdparametri tyhjolaatikon tyhjotasoa såådettåesså.10 water trap parts to the liquid level. In one embodiment of the invention, flexible hoses are connected to the suction foot part, through which the effluent is discharged and the height position of which can be adjusted. The other ends of these flexible flow paths are connected, for example, to a plate whose height position can be adjusted. Thus, the height of the outflow opening with respect to the box can be adjusted, and thus the difference in height between the liquid surface level above and below the liquid surface level of the suction foot can be adjusted, which is an essential control parameter when adjusting the vacuum level of the vacuum box.

Keksinnon erååsså suoritusmuodossa såådetåån imujalan ylåpuolisen ja 20 alapuolisen nestepinnan vålistå korkeuseroa varustamalla laite kåånty-måån nivelåidyllå ulosvirtauskourulla, jonka ylåjuoksun kynnyksen korkeusasemaa voidaan muuttaa ja siten edellå mainittuun korkeusasemaan perustuen sååtåå imujalan painevaikutus ja sen aikaansaama tyhjdtaso - J imulaatikossa.In one embodiment of the invention, the height difference between the upper and lower liquid surfaces of the suction leg is adjusted by providing the device with a pivoted articulated outflow chute, the upstream threshold of which

.·. r 25 : Keksinndn erååsså suoritusmuodossa såådetåån imujalan ylåpuolisen ja alapuolisen nestepinnan vålistå korkeuseroa vaikuttamalla imujalan ulosvirtausjuoksutuksen virtausvastukseen erillisen venttiililaitteen avulla.. ·. r 25: In one embodiment of the invention, the height difference between the liquid surface above and below the suction foot is adjusted by influencing the flow resistance of the outflow flow of the suction foot by means of a separate valve device.

' : 30 . ' Keksinnon mukaisen menetelmån erååsså suoritusmuodossa vaikutetaan imujalan aikaansaamaan alipaineeseen tyhjdlaatikossa tuottamalla pai-neilmaa vesilukko-osaan. Tålloin paineilman virtausmååråå sååtåmållå muutetaan vesilukko-osan nesteen tiheyttå ja siten såådetåån imujalan 35 aikaansaamaa tyhjovaikutusta imulaatikossa.': 30. In one embodiment of the method according to the invention, the vacuum created by the suction foot in the empty box is acted upon by producing compressed air in the water trap part. In this case, by adjusting the flow rate of the compressed air, the density of the liquid in the water trap section is changed, and thus the vacuum effect caused by the suction foot 35 in the suction box is irradiated.

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Keksinn6n mukaiselle menetelmålle paperikoneen vedenpoistoelementin tyhjotason sååtåmiseksi on pååasiallisesti tunnusomaista se, ettå mene· telmåsså kåytetåån sellaista imulaatlkkoa, joka on jaettu våliseinillå paperiradan leveyssuunnassa lohkoihin, jolloin kunkin lohkon alipaine-5 taso on såådettåvisså halutuksi muuttamalla kussakin lohkossa olevan nestepatsaan korkeutta.The method according to the invention for controlling the void level of the dewatering element of a paper machine is mainly characterized in that the method uses a suction tube which is divided into a section at the upper part of the paper web in the width direction of the paper web.

Kekslnndn mukaiselle laitteelle paperikoneen vedenpoistoelementin tyhjotason sååtåmiseksi on pååasiallisesti tunnusomaista se, ettå Imulaa-10 tikko on jaettu paperIralnan leveyssuunnassa lohkoihin, jolloin kuhun-kin lohkoon johtaa oma nestevirtauksen purkukanava tal vastaava laite, jonka avulla voidaan sååtåå alapuolisen vesilukko-osan ylåpuolisen nesteplnnan korkeustasoa ja sltå painetasoa, joka valkuttaa kussakin lohkossa.The device according to the invention for adjusting the void level of a dewatering element of a paper machine is mainly characterized in that the suction-10 rod is divided into blocks in the width direction of the which whitens in each block.

1515

Keksintdå selostetaan seuraavassa viittaamalla oheisien piirustuksien kuvioissa esltettyihin kekslnndn eråisiin edullisiln suoritusmuotoihin, joihin keksintoå el ole tarkoitus kuitenkaan yksinomaan rajoittaa.The invention will now be described with reference to some preferred embodiments of the invention shown in the figures of the accompanying drawings, to which, however, the invention is not intended to be exclusively limited.

20 Kuvlossa 1A on esltetty tekniikan tason mukaiset vedenpoistoelementit viiraosalla.Figure 1A shows prior art dewatering elements on a wire section.

Kuvlossa IB on esitetty kaaviomaisesti tekniikan tason mukainen veden-poistoelementti.Figure 1B schematically shows a prior art dewatering element.

2525

Kuviossa 1C on esitetty leikkaus I-I kuviosta IB.Figure 1C shows a section I-I of Figure IB.

Kuvlossa 2 on esitetty keksinnon ensimmåinen edullinen suoritusmuoto ·. aksonometrisenå esityksenå.Figure 2 shows a first preferred embodiment of the invention. as an axonometric representation.

30 . Kuviossa 3 on esitetty leikkaus II-II kuviosta 2.30. Figure 3 shows a section II-II of Figure 2.

Kuviossa 4 on esitetty kekslnndn toinen edullinen suoritusmuoto aksono-metrisend esityksenå.Figure 4 shows another preferred embodiment of the invention in the form of an axonometric view.

3535

Kuviossa 5 on esitetty leikkaus III-III kuviosta 4.Figure 5 shows a section III-III of Figure 4.

Kuviossa 6 on esitetty keksinnon kolmas edullinen suoritusmuoto.Figure 6 shows a third preferred embodiment of the invention.

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Kuviossa 7 on esitetty kuvion 6 suoritusmuotoon liittyvå vuotovirtauk-sen kurlstuksen sflfltd.Fig. 7 shows a leakage flow suction sflfltd associated with the embodiment of Fig. 6.

Kuviossa 8 on keksinndn neljås edullinen suoritusmuoto.Figure 8 shows a fourth preferred embodiment of the invention.

55

Kuviossa 9 on keksinndn viides edullinen suoritusmuoto.Figure 9 shows a fifth preferred embodiment of the invention.

Kuviossa 10 on esitetty kuvioiden 2 ja 3 suoritusmuotoon liittyvå radan poikittaissuuntainen alipaineen sååtdjårjestely.Fig. 10 shows a transverse vacuum control arrangement associated with the embodiment of Figs. 2 and 3.

1010

Kuviossa 11A on esitetty imulaatikko pååltåpåin ja våliseinien vinoon asettelun ensimmåinen suoritusmuoto.Fig. 11A shows a first embodiment of the suction box on the top and the sloping arrangement of the partitions.

Kuviossa 11B on esitetty våliseinien vinoon asettelun toinen edullinen 13 suoritusmuoto.Figure 11B shows another preferred embodiment 13 of the oblique arrangement of the partitions.

Kuviossa 1A on esitetty kaaviomaisesti tekniikan tason mukaista viira-vientiå, jonka yhteydesså on vedenpoistoelementit 10a,10b,10c ja lOd. Imulaatikon 11 ylåpuolisessa alipainetilassa C pidetåån yllå alipainet-20 ta imujalan 12 avulla alipainetason riippuessa imujalan nesteen N ylå-puolisen nestepinnan 14a ja alapuolisen vesilukko-osan 13 nestepinnan 14b vålisestå korkeuserosta.Figure 1A schematically shows a prior art wire export with dewatering elements 10a, 10b, 10c and 10d. In the vacuum space C above the suction box 11, the vacuum 20 is maintained by the suction foot 12, the vacuum level depending on the height difference between the upper liquid surface 14a of the suction foot liquid N and the liquid surface 14b of the lower water trap portion 13.

Kuviossa IB esitetysså tekniikan tason ratkaisussa pidetåån nesteen N ! 1 25 ylåpinnan 14a taso halutussa pisteesså vuotoilman V, ja poistoilman V2 virtausta såatåmallå. Alkutilanteessa saadaan aikaan alkutyhjo pumpun P avulla.In the prior art solution shown in Fig. 1B, the liquid N! 1 25 the level of the upper surface 14a at the desired point by controlling the flow of the exhaust air V2 and the exhaust air V2. In the initial situation, an initial vacuum is created by means of pump P.

Kuviossa 1C on esitetty leikkaus I-I kuviosta IB. Imujalan 12 alapinnan 30 14b ja ylåpinnan 14a vålinen korkeusero h eli nestepatsaan korkeus mååråå tyhjdlaatikossa 11 sen tyhjdtilassa C vallitsevan alipaineen.Figure 1C shows a section I-I of Figure IB. The height difference h between the lower surface 30 14b and the upper surface 14a of the suction foot 12, i.e. the height of the liquid column, determines the vacuum prevailing in the empty box 11 in its empty space C.

Kuviossa 2 on esitetty keksinndn ensimmåinen edullinen suoritusmuoto. Imulaatikko 11 kåsittåå ylåpuolisen imulaatikko-osuuden 11a ja siitå 35 alaspåin johtavan paperiradan leveyssuunnan yli ulottuvan kanavaosuuden lib. Kanavaosuuden lib alapuoliseen tilaan E on kytketty joustavat 5 90443 taipulsat putket 15a,15b,15c... joiden ylåpaådyt on yhdistetty levyyn 16. Levyå 16 pystysuuntaisesti liikuttamalla (nuoli L,) saadetaan imuja-lan alapuolisen nesteplnnan korkeustasoa ja siten imujalan alkaansaamaa tyhjdå iraulaatikon 11 yl&puolisessa alipainetilassa C.Figure 2 shows a first preferred embodiment of the invention. The suction box 11 comprises an upper suction box portion 11a and a channel portion lib extending over the width direction of the paper path leading downwards therefrom 35. Connected to the space E below the channel section lib are flexible flexible tubes 15a, 15b, 15c ... the upper ends of which are connected to the plate 16. By moving the plate 16 vertically (arrow L,) the height of the liquid surface below the suction foot is obtained. in top & side vacuum mode C.

55

Kuviossa 3 on esltetty kuvion 2 leikkaus II-II. Viira W viedaan veden-poistolistojen 17a,17b ja 17c ylåpuolitse ja alipaine imulaatikon 11 alipainetilassa C yllapidetaan ja saadetaan imujalan 12 alapinnan 14b korkeutta saatamalla, saatamalla kulloisessakin sååtovaiheessa imujalan 10 ylåpinnan 14a ja imujalan alapuolisen nestepintatason 14b valista kor-keuseroa. Mainittu korkeuseron H såatåminen tapahtuu saatåmalla tai-puisten letkujen 15a,15b... purkuaukon korkeusasemaa levya 16 liikuttamalla (nuoli L,).Figure 3 shows section II-II of Figure 2. The wire W is passed above the dewatering strips 17a, 17b and 17c and the vacuum in the vacuum space C of the suction box 11 is maintained and obtained by raising the height of the lower surface 14b of the suction foot 12, bringing the upper surface 14a of the suction foot 10 and the suction foot below 14. Said adjustment of the height difference H takes place by obtaining the height position of the discharge opening of the hoses 15a, 15b ... or by moving the plate 16 (arrow L 1).

15 Kuviossa 3 esitetysti voldaan lisåsaatdparametrina pitaa erillisissa alkusååtovaiheissa kanavan 17 kautta tuotua lisånestetta, joka voidaan tuoda pumppulaitteen P2 avulla ja venttiiliå 18 saatamalla.As shown in Fig. 3, an additional supply parameter is the additional liquid introduced via the channel 17 in the separate initial setting steps, which can be introduced by means of the pump device P2 and by supplying the valve 18.

Kuviossa 4 on esitetty keksinndn toinen edullinen suoritusmuoto, jossa 20 nestepinnan 14b korkeustaso ja ulosvirtaustaso saadetaan kaukalon 20 ulosvirtauskynnyksen reunan 21 korkeusasemaa saatamalla. Kaukalo 20 on ;'· j liikutettavissa nivelen 19 ympåri ja kaukalon ulosvirtausreuna 21 on saadettåvissa korkeusasemaltaan nuolella Lj esitetysti. Kaukalo 20 on kytketty imulaatikon 11 imujalkaosan lib alaosaan.Figure 4 shows another preferred embodiment of the invention, in which the height level and the outflow level of the liquid surface 14b 20 are obtained by bringing the height position of the edge 21 of the outlet threshold of the trough 20. The trough 20 is movable around the joint 19 and the outflow edge 21 of the trough can be reached from its height position as shown by the arrow Lj. The trough 20 is connected to the lower part of the suction foot part lib of the suction box 11.

: 25: 25

Kuviossa 5 on esitetty leikkaus III-III kuviosta 4. Kaukaloa 20 liikuttamalla saadetaan kaukalon ylapuolisen nestepinnan 14b ja imujalan ylapuolisen nestepinnan 14a vålista korkeuseroa H ja sita alipainetta, joka imujalan avulla aikaansaadaan laatikon 11 alipainetilaan C.Fig. 5 shows a section III-III of Fig. 4. By moving the trough 20, the height difference H between the upper liquid surface 14b of the trough and the upper liquid surface 14a of the suction foot and the vacuum created by the suction foot in the vacuum space C of the box 11 is obtained.

3030

Kuviossa 6 on esitetty keksinnon suoritusmuoto, jossa imulaatikon 11 imujalan 12 alapuoliseen nestepintaan ja siten alapuolisen nestepinnan ja ylapuolisen nestepinnan 14a,14b valiseen korkeuseroon vaikutetaan saatamalla ulosvirtausta imujalan 12 alapuolisesta tilasta D. Ulosvir-35 tausta tilasta D saadetaan venttiilin 22 avulla.Fig. 6 shows an embodiment of the invention in which the liquid surface below the suction leg 12 of the suction box 11 and thus the height difference between the lower liquid surface and the upper liquid surface 14a, 14b is influenced by causing an outflow from the space D below the suction leg.

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Kuviossa 7 on esitetty eras kuvion 6 venttiilin toteutusmuoto, jossa virtausaukon 23a ja 23b yhteyteen on sovitettu reikalevy 24, jonka Hike on saadettavissa nuolella L, esitetysti ja siten on saadettavissa se peittoaste, jolla levy 24 peittaa aukkoja 23a ja 23b. Peittoasteen 5 mukaan sååtyy ulosvirtausvastus ja siten imujalassa olevan alapuolisen nestepinnan 14b korkeustaso suhteessa ylapuoliseen imujalan nestepinnan tasoon 14a. Hy6s kuvion 6 suoritusmuodossa voidaan nestepinnan tasoon imujalassa 12 vaikuttaa edelleen tuomalla kuten on esitetty kuvion 3 suoritusmuodossa lisanestetta venttiililaitteen 18 saatamånd kanavan 17 10 kautta. Lisanesteen tuonti voi tapahtua nestetankista T pumppulaitteen Pj aikaansaamalla ylipaineella.Fig. 7 shows an embodiment of the valve of Fig. 6, in which a hole plate 24 is arranged in connection with the flow opening 23a and 23b, the Hike of which can be obtained with arrow L, as shown, and thus the degree of coverage with which the plate 24 covers the openings 23a and 23b. According to the degree of coverage 5, the outflow resistance and thus the height level of the lower liquid surface 14b in the suction foot relative to the upper liquid surface level 14a of the suction foot is determined. In the embodiment of Fig. 6, the level of the liquid surface in the suction foot 12 can be further influenced by introducing, as shown in the embodiment of Fig. 3, additional liquid through the channel 17 10 provided by the valve device 18. Additional liquid can be imported from the liquid tank T with the overpressure provided by the pump device Pj.

Kuviossa 8 on esitetty keksinnOn lisasuoritusmuoto, jossa imujalan 12 alapuoliseen tilaan D on tuotu ilmayhde 25, jonka kautta puhalletaan 15 paineilmaa F imujalan 12 alapuolisen tilan D seinamien 26 ja sisdpuoli-sen seinaman 27 valiseen yldspain aukeavaan avoimeen tilaan G. Imujalan alapuolisen tilan nestepinta 14b pidetåån vakiona ja vesilukko-osan nesteen tiheyteen vaikutetaan paineisen ilman tuonnilla kanavan 25 kautta ja/tai sååtåmålla kanavan 25 asemaa.Fig. 8 shows a further embodiment of the invention in which an air connection 25 is introduced into the space D below the suction foot 12, through which compressed air F is blown into the open space G between the walls 26 and the inner wall 27 of the space D below the suction foot 12. as a constant and the density of the liquid in the water trap part is influenced by the introduction of compressed air through the duct 25 and / or by adjusting the position of the duct 25.

2020

Kuviossa 9 on esitetty keksinndn suoritusmuoto, jossa imulaatikko 11 k&sitt&a varsinaisen imulaatikko-osuuden 11a ja siita alaspdln aukeavan koneen poikittaisuuntaisen varsinaisen imujalkakanavaosuuden lib, jonka alapuolisesta tilasta johtaa putkiyhde 27 sdili66n 29. Kanavassa 27 25 sijaitsee sååtdventtiili 28. Kanavaan 27 aukeavat ylfispain avoimet yhteet 27a ja 27b. Tilojen 27a ja 27b nesteen pintatasojen 14b, ja 14b2 korkeusasemaan Ja vastaavasti sflilion 29 nestepinnan 14b3 korkeusasemaan vaikutetaan venttiililaitteen 28 kuristusta muuttamalla. Nestepintojen karkea asettelu voi tapahtua my6s tåsså suoritusmuodossa niin kuin 30 aiemmissa tuomalla pumpun P3 avulla nestesåilibsta T lisånestettå venttiilin 18 kautta kanavaan 17 ja edelleen kanavaan 27.Fig. 9 shows an embodiment of the invention, in which the suction box 11 27b. The height position of the liquid surface planes 14b, and 14b2 of the spaces 27a and 27b and the height position of the liquid surface 14b3 of the splilion 29, respectively, are affected by changing the throttle of the valve device 28. Coarse arrangement of the liquid surfaces can also take place in this embodiment as in the previous ones by introducing additional liquid from the liquid reservoir T via the valve 18 into the channel 17 and further into the channel 27 by means of the pump P3.

Kuviossa 10 on esitetty l&hinnfl kuvion 2 ja 3 suoritusmuotoihin liitty-va erityissuoritusmuoto, jossa kukin kanava 15a,15b,15c... on saadetta-35 visså korkeussuunnassa erillisesti (nuolet L,), jolloin imulaatikko 11 on jaettu erillisiin seinilla toisistaan erotettuihin alipainelohkoihin 7 90443 11',11",11"'... Nåin olien voidaan keksinnon tåsså suoritusrauodossa alkaansaada halutun suurulnen allpalne koneen erl leveyskohdissa ja nåln olien voidaan vaikuttaa alipaineen mååråån ja alipaineprofilliin mainittujen putkien 15a,15b... korkeusasemaa sååtåmållå. Nåin olien 5 voidaan vedenpoiston tasoa eli alipainetta lohkoissa 11',11"... sååtå-mållå vaikuttaa halutulla tavalla paperirainaan ja sen kosteusprofii-liin paperirainan leveydeltå. Menetelmå on kåytettåvisså my6s muissa esitetyisså suoritusmuodoissa.Fig. 10 shows a special embodiment related to the embodiments of Figs. 2 and 3, in which each channel 15a, 15b, 15c ... is sent separately in the height direction (arrows L 1), whereby the suction box 11 is divided into separate vacuum blocks 7 separated from each other by walls. 90443 11 ', 11 ", 11"' ... Thus, in this embodiment of the invention, the desired large bottom flange can be obtained at the erl widths of the machine, and these oils can be influenced by the amount of vacuum and the height profile of said pipes 15a, 15b ... Thus, the level of dewatering, i.e. the vacuum in the blocks 11 ', 11 "... can be influenced in the desired manner by the paper web and its moisture profile across the width of the paper web. The method can also be used in other embodiments shown.

10 Kuviossa 11A on esitetty imulaatikko 11 pååltåpåin ja paperirainan kulkusuunta on esitetty nuolella T,. Imulaatikko 11 on jaettu lohkoihin 11',11",11"'... kuten on esitetty kuvion 10 suoritusmuodossa. Våli-seinåt S',S",S"'... jakavat imulaatikon 11 edellå mainittuihin lohkoihin 11',11",11"'... Kuvion 11A suoritusmuodossa lohkojen vålisenåt 15 S',S",S"'... ovat asetettu vinoon paperiradan kulkusuuntaan T, nåhden, jolloin våltetåån våliseinien aiheuttamat alipainetasojen pitkåt epå-jatkuvuuskohdat paperirainassa. Kuvion 11A suoritusmuodossa ovat vå-liseinåt asetettu vain hieman viistoon asentoon paperiradan kulkusuuntaan T, nåhden.Fig. 11A shows the suction box 11 from above and the direction of travel of the paper web is indicated by the arrow T 1. The suction box 11 is divided into blocks 11 ', 11 ", 11"' ... as shown in the embodiment of Figure 10. The partition walls S ', S ", S"' ... divide the suction box 11 into the aforementioned blocks 11 ', 11 ", 11"' ... In the embodiment of Figure 11A, the partitions 15 S ', S ", S"' .. are set obliquely with respect to the direction of travel T of the paper web, thus avoiding long discontinuities of the vacuum levels in the paper web caused by the partitions. In the embodiment of Figure 11A, the partitions are set only slightly obliquely to the direction of travel T of the paper web.

2020

Kuviossa 11B esitetysså suoritusmuodossa ovat våliseinåt S',S",S"'... asetettu n. 45°:n viistouskulmaan paperiradan kulkusuuntaan T, nåhden ja siten, ettå våliseinien påådyt liittyvåt toisiinsa.In the embodiment shown in Fig. 11B, the partitions S ', S ", S"' ... are set at an oblique angle of about 45 ° with respect to the direction of travel T of the paper web and so that the ends of the partitions are connected to each other.

Claims

A method of controlling the vacuum level in the dewatering element of a paper machine, the dewatering element (10a, 10b ...) comprising a vacuum space (C) above the suction box (11), in which a vacuum is maintained by means of a suction foot (12). is formed by a liquid statue, the suction foot (12) comprising an upper surface (14a) of a liquid (N) and a lower surface (14b) bounded to the water-lock portion of the liquid statue, by which method the vacuum level of the vacuum space 10 (C) is controlled. the suction box (11) in the desired manner by regulating the level (14b) on the liquid surface of the lower water-locking part of the suction foot (12), which can therefore be used to draw on such a suction box (11), which divided by partition walls into sections (11 ', 11 ", 11"') in the width direction of the paper web, whereby the vacuum level of each section can be adjusted in the desired manner by breathing on the height (h) of the liquid statue in each Episode.

2. A method according to claim 1, characterized in that the suction box (11) is used in the method, where a channel 20 (15a, 15b ...) is connected to each section (11 *, 11 ", 11 "'), preferably a buoyant hose, wherein the height of the free spirit of the channel (15a, 15b ...) can be controlled by controlling the height of the 6th surface (14a) of the liquid statue (12) in each section (11 ', 11 ", 11"').

3. A method according to any one of the preceding claims, characterized in that, in the process, such a suction box (11) is used, where ducts extend to the lower liquid space thereof, advantageously tube (15a, 15b, 15c ...), the spring flame can be regulated, whereby the headlamp on the free spirit of the ducts (15a, 15b, 15c ...) is breathed by regulating the vacuum level to be maintained in the upper vacuum space t (C) of the suction box (11). .

4. A method according to any one of the preceding claims, characterized in that, in the process, the vacuum of the vacuum space is regulated by introducing pressurized air via a duct (23) to a lower liquid space, whereby the density of the liquid can be controlled. the water trap portion after the feed bar on the compressed air and the high cap and the desired pressure level in the vacuum compartment (C). 12 90 443

Apparatus for controlling the vacuum level in the dewatering element of a paper machine, the device including a suction box (11) in connection with the dewatering element (10a, 10b, 10c.), Maintaining the desired negative pressure level in the upper vacuum space (C) of the suction box by means of a suction foot (12), the suction foot (12) comprising a liquid surface (14a) bounded to the vacuum space (C) and a lower wet surface (14b) bounded to the lower water locking part, the installation comprising means for regulating the vacuum level of the upper vacuum space (C) of the suction box (11), by means of which means the head level of the liquid surface (14b) of the lower water trap portion (13) and through the vacuum level of the upper vacuum space can be noted, that the suction box (11) is subdivided into sections (11 ', 11 ", 11"' ...) in the width direction of the paper web, whereby it leads its own outflow channel (15a, 15b ...) for the liquid stream to each a section or corresponding device, by means of which the height level of the upper liquid surface (14b) of the lower water locking member (13) and the pressure level acting in each section (11 ', 11 ", 11') can be adjusted ”...).

6. Device according to the preceding claim, characterized in that there is a channel (15) in connection with each section 25 (11 ', 11 ", 11"' ...) in which the high lid of these spirits can be controlled.

7. Device according to claim 5 or 6, characterized in that the partitions (S ', S ", S"' ...) of the sections (11 ', 11 ", 11"' ...) are inclined in relation to the flow direction of the paper web, avoiding discontinuous steels at the vacuum levels caused by the paper web. Device according to any one of the preceding claims 5-7, characterized in that the device comprises one or more rows 35 (15a, 15b ...) which can be moved in a vertical direction in connection with the liquid space of the water lock part (14). whereby by controlling the height of the outflow opening of the rudder (15a, 15b ...), the head difference between the upper liquid surface (14a) and the lower liquid surface (14b) and the vacuum level prevailing in the vacuum space can be controlled ( C).

Device according to any one of the preceding claims 5-8, characterized in that there are several hoses (15a, 15b) which are fixed to a disc (16) or the like, whereby by breathing high the the disc (16) can breathe the cap of the open free spirit of the hose obtained at the disc and thus the level of depression prevailing in the space (C).

Device according to claim 8 or 9, characterized in that the ducts (15) are flexible hoses.

Device according to any one of the preceding claims 5-10, characterized in that the installation comprises a compression air drip (25) in connection with the water locking part (13), controlling the effective height (h) of the suction foot ( 12) with the compressed air introduced through the liner (25) by controlling the tightness of the liquid 20 of the water lock member.