CA2483818C - Method for the production of a web of tissue material - Google Patents
Method for the production of a web of tissue material Download PDFInfo
- Publication number
- CA2483818C CA2483818C CA2483818A CA2483818A CA2483818C CA 2483818 C CA2483818 C CA 2483818C CA 2483818 A CA2483818 A CA 2483818A CA 2483818 A CA2483818 A CA 2483818A CA 2483818 C CA2483818 C CA 2483818C
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- Canada
- Prior art keywords
- accordance
- web
- equal
- reel
- drying
- Prior art date
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Classifications
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21F—PAPER-MAKING MACHINES; METHODS OF PRODUCING PAPER THEREON
- D21F3/00—Press section of machines for making continuous webs of paper
- D21F3/02—Wet presses
- D21F3/04—Arrangements thereof
- D21F3/045—Arrangements thereof including at least one extended press nip
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
- B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
- B65H18/00—Winding webs
- B65H18/08—Web-winding mechanisms
- B65H18/26—Mechanisms for controlling contact pressure on winding-web package, e.g. for regulating the quantity of air between web layers
-
- 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
- D21F1/02—Head boxes of Fourdrinier machines
-
- 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
- D21F1/02—Head boxes of Fourdrinier machines
- D21F1/028—Details of the nozzle section
-
- 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
- D21F11/14—Making cellulose wadding, filter or blotting paper
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21F—PAPER-MAKING MACHINES; METHODS OF PRODUCING PAPER THEREON
- D21F3/00—Press section of machines for making continuous webs of paper
- D21F3/02—Wet presses
- D21F3/0281—Wet presses in combination with a dryer roll
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21F—PAPER-MAKING MACHINES; METHODS OF PRODUCING PAPER THEREON
- D21F5/00—Dryer section of machines for making continuous webs of paper
- D21F5/02—Drying on cylinders
- D21F5/04—Drying on cylinders on two or more drying cylinders
- D21F5/042—Drying on cylinders on two or more drying cylinders in combination with suction or blowing devices
- D21F5/044—Drying on cylinders on two or more drying cylinders in combination with suction or blowing devices using air hoods over the cylinders
-
- 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
- D21F9/006—Complete machines for making continuous webs of paper of the twin-wire type paper or board consisting of two or more layers
Landscapes
- Paper (AREA)
- Sanitary Thin Papers (AREA)
- Replacement Of Web Rolls (AREA)
Abstract
The invention relates to a method for the production of a web of tissue material (12) by means of a tissue machine (10) comprising a material wind-on element (14) and an endless carrier belt (16) which is used to guide the web of tissue material (12) through a press gap (23) formed between a can drier (18) and a counter unit (20), wherein said material wind-on element is a multilayered element with at least two different types of material being fed thereto. At the connection with the press gap, the web of tissue material is wound on by means of a winding device (24). Preferably, the hardness of the roll (80) thus formed is influenced in a predefined manner, being controlled and/or regulated in particular. The invention also relates to a corresponding tissue machine.
Description
WO 03/091499 8CT/Ei~03/50074 I4ethod fos the produat~.o~. of a r~eb cf tissue m3beza.al . ~.. ~..--'~ha inver~tior~ relates to a method ~or the production of a web of tissue maLexial. This carx be, in particular, such t~.~~ue grades ae, for example, "toilet tissue".
"facial tissue", sexwiezte paper and/or and the l~.ke.
Furthermore, the inv~ntion relates to a tissue triachlne for aarxying out the method.
'10 In partiCUlar in the Case of the aforementioned tipsue grades, what is important, inter alia, is the speci~~,c voZutrie ( "bulk" , measured in, [cm3/ga ) , which should be as high as possible, and what is known as the "hamd, feel" , whicki is a measure o~ how p7,eaeant th~a tissue, for example faoa.al tissue, feels when gripped. Since this rileasure depez~ds on the 9ubj ective ~ s~nse of the user, there a.s no obaective measurement method.
Characzexistics such. as softness, ~relvetinesa, ~7.at surface topography (as opposed to roughly creped and/or embossed surfaces) benefit a high measure of "hand fael~ . A "hand feel" value is 8etex~nir~.ed as the result o~ the subjective a99eesment of a larg~ number of test people.
of cQUxse, a certai.~1 minimum strength, which suits the requirements of the user, ie also important'for such a , t a. ss~e product .
1, number of concepts of tissue machines have already been propaeed, which gera,axally have the object of improving the tissue Characteristics, The obj eeL of the invention. is to pro~ride an improved method and an improved tissue machine of the type mentioned aL the beginning with which a tissue product or tissue paper, in particular "toile~C Lissue" and "racial tissue" with a ps,ztieul,arly high "hand feed"
arid high specific volume (bulk) with acceptable strength is ensured. In the caeo of a "facial tzssue'~
"facial tissue", sexwiezte paper and/or and the l~.ke.
Furthermore, the inv~ntion relates to a tissue triachlne for aarxying out the method.
'10 In partiCUlar in the Case of the aforementioned tipsue grades, what is important, inter alia, is the speci~~,c voZutrie ( "bulk" , measured in, [cm3/ga ) , which should be as high as possible, and what is known as the "hamd, feel" , whicki is a measure o~ how p7,eaeant th~a tissue, for example faoa.al tissue, feels when gripped. Since this rileasure depez~ds on the 9ubj ective ~ s~nse of the user, there a.s no obaective measurement method.
Characzexistics such. as softness, ~relvetinesa, ~7.at surface topography (as opposed to roughly creped and/or embossed surfaces) benefit a high measure of "hand fael~ . A "hand feel" value is 8etex~nir~.ed as the result o~ the subjective a99eesment of a larg~ number of test people.
of cQUxse, a certai.~1 minimum strength, which suits the requirements of the user, ie also important'for such a , t a. ss~e product .
1, number of concepts of tissue machines have already been propaeed, which gera,axally have the object of improving the tissue Characteristics, The obj eeL of the invention. is to pro~ride an improved method and an improved tissue machine of the type mentioned aL the beginning with which a tissue product or tissue paper, in particular "toile~C Lissue" and "racial tissue" with a ps,ztieul,arly high "hand feed"
arid high specific volume (bulk) with acceptable strength is ensured. In the caeo of a "facial tzssue'~
with a mass per unit area (grammage) vf, for example, 15 g/m', the aim is a specific volume (bulk) of 10 eFns/g and higher, arid it1 the case of a mass per unit area (grammage) of 23 g/m~ , a specific vo7.ume (bulk) of 9.0 cm9/g and higher. Tr1 additioxi, the relevaxit tissue machine 9hvuld be as simple as possible ~.ri eonStrucLion and economical. At the same time, a,e marzy di~f~rent product gxadee as possible should be Capable of production on this machine.
to According CO zh2 l~lverstivn, this obj ect is achieved by a method for th~ production of a web of LisSUe material by means of a tissue machine compxieing a flow box and an endless fiv~pporting belt, with which the tissue web is led through a press nip formed between a drying cylinder and an oppQfiing unit, the flow box used being a mla,ltilaye~' flew box, at lea9t twa stock grades being supplied to this multilayer flow box, arid the 'C~.ssue web being wound up by means of a re~1-up after the preys nip, th~ hardness of the reel produced preferably beir~.g influezlc~d ~.n a predetinable away, in part a.cular controlled and/or regulated.
Tn this ease, the dxy~,ng cylir~.der used is p~eferab~.y a 2 5 Yawkee cyl ir~dcr , The 1 ixie Force produc~d ire, the winding nip expediently selected to be less than or equal to o . a 1sN'/m.
Accvrdizzg to a preferred pxaetical configuration of the method according to Lhe invent~,oxi, use i9 made of a Former havir~g two circulating endless belts, which rurl together, forming a stock inlet gap, and are then guided ovex a forming element, such aS iz1 particular a tox'nting roll, the innor belt that comes into contaot with the forming elemez~t preferably forming the tra.n~sport belt. Use is pr~afarably made of a crescent former, Whose inner belt is fox~led by a Felt.
to According CO zh2 l~lverstivn, this obj ect is achieved by a method for th~ production of a web of LisSUe material by means of a tissue machine compxieing a flow box and an endless fiv~pporting belt, with which the tissue web is led through a press nip formed between a drying cylinder and an oppQfiing unit, the flow box used being a mla,ltilaye~' flew box, at lea9t twa stock grades being supplied to this multilayer flow box, arid the 'C~.ssue web being wound up by means of a re~1-up after the preys nip, th~ hardness of the reel produced preferably beir~.g influezlc~d ~.n a predetinable away, in part a.cular controlled and/or regulated.
Tn this ease, the dxy~,ng cylir~.der used is p~eferab~.y a 2 5 Yawkee cyl ir~dcr , The 1 ixie Force produc~d ire, the winding nip expediently selected to be less than or equal to o . a 1sN'/m.
Accvrdizzg to a preferred pxaetical configuration of the method according to Lhe invent~,oxi, use i9 made of a Former havir~g two circulating endless belts, which rurl together, forming a stock inlet gap, and are then guided ovex a forming element, such aS iz1 particular a tox'nting roll, the innor belt that comes into contaot with the forming elemez~t preferably forming the tra.n~sport belt. Use is pr~afarably made of a crescent former, Whose inner belt is fox~led by a Felt.
It is also particularly advanLac~eoua if the tis9ue web, togethex with zhe supporting belt, is led through at least oz.~e shoe press . Tn this case, the opposing unit asa~,gned to the dry~.ng cylinder that is used is expediently a shoe press uzliL .
A high-temperature hood Can be provided, above the dx'y~.ng cylinder or Yankee cyl~.nder.
A further improvenletzt ire the tissue product properties can else be achieved in parL~.cular by the tise~.e web being doctored off the drying cylinder by means oL a crepi~g doctor, ~.n parLiCUlar a th~.n crep~.ng doctox.
one or more of the following stock grades ~.a preferably used:
- fibers made ox haxdwood, in particular short-fiber chemical. pulps ' 20 - fibers made of softwood, in particular long-fiber ' chemical pulps - CTMP (chemiC~l-thermojnechaaical pulp).
r Prefereriee is given. to stock grace mixtures in which the proportion of fibers made of hazdwood lies in a I range from about 50% to about BO~S, the proportion of ~ibere made of softwood lies in a range from about 20%
to abou'G 50% and/or the proportion of CTMQ (chemzcal thermomeahanical pulp) lies iz~ a range from 0% to about 20%.
Tht~e, amongst others, for example the following stock grad~ mixtures are conceivable:
Ex. "a" Ex. "b" Ex. "a~.
I Hardwood (50 to 80%) 50 60 Softwood (20 t0 50%) 30 40 20 CTMP (0 to 20k) 20 0 10 I
I
I
~z~ this case, in particular the C'fflP in a respective stock grade mixture ~,mpro~cres the specific volume (bulk) According to a preferred pract~.ca1 configuration of the method accordir~g to th~ invantion, the LisSue web is led around the drying cy~.inder after the press nip, the drying in the x~levant wrap region preferably being intensified by a drying hood, in partivular a high t~ntpera.ture hood.
2t is of particular advantage it Lhe Tnultilayer flow box is supplied with eat least two differer~t stQCk grades axed in this case for short fibers obtained from hardwood LO be used fox the layer of the t~.ssue zueb that faces tha dryiz~.g cylinder surface and for l.oag fibers 4bxained fzorn softwood to be used far the layer on the opposite side of the web, It is also of advantage in particular if the ~low box i~ loaded with at least two layers with different fibrous stocks, the stock with the short fibers obtained from hardwood being add~d into the layer of th~ flocu bo~c which forms the Side of the tissue web Z5 that faced the drying ox Yankee cylinder surface. The second layer is exped~.ently loaded with long fibers made Pram softwood. Alterr,~atively or additiozially, ' this second layer Can also be loaded with ~.oz~,g ~sbera and C'~tF and/or with long Fibers and CMF arid short 3o fibers. Th~.s layer forms the second layer of the tissue web, which faces the drying hood in the drying process. Tt therefore never comes into contact with i the dryixig or Yankee cylinder surface. Using these i method Steps, Che "hand f~cl"' and ~~bulk" values are 35 improved by s.bout 5~ and more.
Use i~ preferably made of a multilayer flow box, who~sa nozzle is subdivided into at leapt two channels by mews of at least one slat extending over the entzre .l f rnaehine~ width. zn this case, the nozzle is expedieritl.y subd~.vided at least s,.a.batantially symtt~etrieally into two charu~,els by a slat .
Particular~,y good results are achieved if the slat exter~.ds outward beyond the noazle in the region of the outlet gap. This counteracts any mixing of the plies.
Advantageously, uSe can be rilaCle of a flow box havi~,g l0 dilution water regulation and/or control section by section ever the machine width, in order to be able to set a respectively desir~d cross-machine grammage prof i~,e _ xn specific cases i,t ~.s advaritagevus if in each vape dilut~.on w~.t~r regu~,ation and/or contrel is provided fcr at least Lwo Layers. P'or example, when a two-layer flow box is used, in each case dilution water' regulation or control can therefore be provided in both layers. if appropriate.
Dilution water regulation ar~d/or control is preferably provided at least in the layez~ facir~.g the forming ox breast roll. In this case, appropriate dilution water regulation and/or control can in particular be providBd only for this one layer, that is to say the outer layer with, respect to the foaming or breast roll. The forming or breast roll can be closed, open yr else evacuated.
The drying of the web by the drying or 'S.'ar~.kee cylir~.der and a drying or hat-air hood is important for the drying process, aacorc~ir~,g to a preferred practical oonfiguration of the method accord~.ng to the invez~tlon, the proportion, of th~ drying contributed by the dx'Yirlg h4od to the drying of the tissue web being choacn tv be greater than the proportion of the drying Con'~z'ibuted by the drying cylinder.
Tn this case, the ratio between the propoz~t~.on o~ the drying from the dxyi~g hood and the proportion of zhe drying from the 8rying cylinder is advantageously chosez~ to be gre~.ter than 55:e~5, in pat'ticul8r greater than or equal 'to 60:80, in particular greater than or equal to 65 ; 35 and preferably greater than Or equal to 7a:3o_ The drying hood is pxefexa,bly operated at a t~mperature ZO which is gxeater than. or equal to 400°C, in par'Cicular gxeater Lhari or equal to 500°C, in particular greater than ox equal to 600aC and preferably greaLex than or equal to 700°C.
The steajn pressure in the dxY~.ng cylinder oan additionally be reduced_ For example, for Lhe steam pressuxe in the drying cylinder, a value is advaatageov.a.sly chosen which is less than Or equal zo 0.7 MPa, in particular lea9 than or equal to 0.6 M8a ar~.d preferably leSS than or ec~tlal zo 0.5 MFa.
As a result, the course of the drying can be raised further. By mea.a~a of the aforementioned rrieasurea, an increase in the "bulk" value by up to 5~ and an improvement xn the "hand feel" value are achiev~ed_ Particulax importance is also attached to wizZding vp the t~.~sue web at the ehd ofi 'Che tissue machine.
3o According to a pxeterred practical configuration of the method according to the invention, a re~1-up ~.s used in which the tissue web is led over a carrier drum and is then wound up onto a spool, in each case a drive prefera~?1y being assigned both. to the carrier drum and to the spool. As a xesult, optimum reeling of zhe web is achieved, without destroying the specific volume bulk) of the paper web produced. Thus. with the use of two d~-zves for the carriex drum arid the spool or the real, in partscular a reductivr~. of the line Force produced in the winding nip ig possible_ Accvrd$rig to an expedient practical eoti~iguraLior~, of the method according Lo Lhe invex~tion, the line tome produced in the winding nip between the earriex drum and the spool is cho~an to be leas thar~ or equal. to 0.B kN/m, in particular less than or equal to 0.5 kN/m and preferably leas thax~ car equal, to 0.2 k1Q/m. Since ID no drive power has to be transmitted betweetl the carriex' drum and the reel, the pressure in the minding nip ox contact nip can be reduced.
6inae tiesue paper is creped. exhibits high eLretch, Z5 that ~,S to Say a high mvdulus of elapticity, and has a loW tensile strength, ne substantial web Lension can be applied in order to ixlcreaae the wir~ding hardaese of the reel.
20 The maximum difference between the cizcumferera,ti~l speed of Lhe reel a~.d th,e c~,xcumterential speed of the carrier roll is preferably less 'Chan 10~ of the eircumferential speed of the earriex roll.
25 According to a preferred pxaatical eorifigura.tion of the method according to the irlveriCioz~., the web tension between the drying cylinder and the carrieY drum is eet, in partiCU~.a~' Controlled and/or regulated, to a pzedefinable desired value via the drive assigned Co 30 the carrier dxuril. ~.zldependently of the line force produced in thn winding n.ip.
on aocourst o~ the crapxr,~g at the ere~7ir~,g doctor, the carrier drum eircumferential speed is lower than the 35 ciroumferential speed of the drying cylinder.
The drive assigned to the spool is advantageously coritx~Qlled and/or xogulated as a function of the speed of the carrier drum.
a -O~ particular zxnportanoe during the production of a.
' soft reel is the control of the "low" line force iii the windir~g nip or eoz~.taet axp. According to a preferz~ed practi,eal configuration of the method according to the lliveritiOT7,, a reel-up is used for this purpose iri which the carrier drurit is mounted in e~ f fixed poe~.tioa and the spool can be moYee~- Accordingly, the growth in the reel diameter ea~1 be compensated for bar means of to appropriate movement o~ the ~poal. In addi'Cian, the line force iz1 xhe winding nip ca,n be set i.n the desired mannex via the mo~crable spool. Ix1 order to compensate for the gXOwth in di~.meter of the reel and in order to set the line ~oroe ix1 the winding rllp, a ComTnon cvntxol loop cars advantageously be used. One expedient configuration of the method aCCOrdirig to the invention ie distinguished bar the fact that. the lin~ foxes in the winding n~.p is determined via a'C leaSZ one force sensor an,d Lh~.s line ~oroe is regulated by means of appropriate moo~ment of the Spool. In priz~ciple, however, for example the spool cax~ also be fixed iri position and the carrier druril can be movable.
Fuzthex~more, such designs ~.n which bath the carrier drum arlq~ the spool Carx respectively be moved are also Z5 conceivable.
~t ~.s possible that the measuxsment accuracy Ot Lhe aera.sors and the setting accuracy (friction) ie no t longer sufficient at iota line foroeQ anal with large, i 30 heavy reels. Iri particular iT1 the cane of line forces in the windir~g nip which are less than or eBual 'Co ' 0.5 kN/m arid in particular less thar~ or equal to 0.2 kN/m, the movable spool is therefore preferably moved away under Control. xr~ this case, the measured 35 vaxiablee used for the moveme~lt away uz~der control can I
in particular be the reel diameter and the position of the spool or the real formed thereon. relative tv the carr~,er drum.
_ g _ Rccord~,~.g to a fuxther advancagevua coxr~~.guratxon of the ~ethvd according to the invention, in order to set, contra. and/or regulate the line farce in the winding nip, the region, of the winding nip can be monitored appropriately by means O~ a CCD camera. Ira. this case, by means of the CCD camera, preferably the reSpeczive distance betweeTl the Carrier dru,t~c~ arid the spool ox the reel Formed oxa. the latter is registered. With such observation of the winding nip region, for example by meaza,~ of a CCD camera, the result is therefore a further possibility o~ monitoring anal setting the winding force. Tt is therefore possible to measure allc~.
display the di~st~nee between the carrier drum sad the reel, . 8y u~si,rng az~. evaluation of the image, it is then again posaib7,e Lo reach a desired value of the hydraulic cylinder pxessure that influences the mo~'able reel arid, via a control device, to execute the i displacement or shift as far as the desired distance or wizld.~.rig force . The gain in bulk can lie, for example, in a rax~.ge From 4 to 8~ . R further advantage is that the "bulk" gain achieved by the Shoe press ie not destroy~d, and therefore the quality of the Web is maintained.
It is also of advara,tage if th.a drive assigned to the ' spool and therefore to the reel i~ rlot changed during the winding operation, that ie to say in part~.cular not when the anew spool is moved beyond th,e primary or winding start position,, in. which tie drive is coupled 3o up and the s8ool is accelerated, to the secondary position on the rails. Controlled winding from start to end therefore results.
The paper qualify can be increased f~.rther by the mesa par unit. ar~a of th.~ tissue ~casb in the uncreped state lying in a range front about 11 g/mo to about 20 g/m~
and a.n t~~ creped state lying in a range from about 14 I g/m'to about 24 g/m~.
- l~ -since, above all in the case of thin papers and ire particular ire, the case of "facial tissue" arid "toilet"
tissue, the formation, that iS Lo say uniformity of the fiber arrangement, playa as important role, the use of s a crescent former is of pdr~icular advantage in these cases in particular. Ts~ this ease, the Web is dawatered, transported, pressed and passed on to the drying cylinder or Yar~kee oylindex an a felt. At Lhe start of dewatexing, an outer ror~.re is still provided.
l0 In addition to improved formation, the result iS also improved strength with possible MD/CMD breakir~g length ratios of 1:1 to 4:1. This ma)Ces it possible to beat the fibers less. This increases the "hulk~~ value. Hy meazl.a of this former 'type, "strength" sari be converted 15 into "bulk". This former typo improves the ppeeifia vvlu~~ ~bulJt) by + 5~ in combination with at least one of the design variants described.
In this case, use can be made in particular of a 20 crescent former, iahose inner or supporting bell, formed by a fell, together with the tissue web, is led over at J.eaet one evacuated device in the Web running direct~,on before 'Che press nip. The evacu4.ted device provided can be, in particular, a suction, roll. As already 25 mentioned, the outer belt provided in the region of the forging el~ment of the crescent former can be formed in particular by a meth belt (wire).
Also of particul,ax advantage, in particular, is the use 30 of a shoe press with a shoe length as measured iz~. the web ria,nn~.ng dixnction of greater thars ox ~quaZ to BD mm and preferably greater than or equal tv 12o mm. ~y means of the shoe press, a lixla force which lies the range from 60 kN/m Lo about 90 kN/m is preferably 35 produced, The maximum pressing pressure in Lhe pXess nip of the shoe px'eSS ils preferably leas than or egual Co 2 bar arid preferably less than or equal to 1.5 bar.
Moreover, the shoe press can comprise a shoe press unit ~rith a blind-drilled press cover. As co~pared wish a suction press roll, a, bulk gain in a rar~.ge from about 15$ to about 20~ oan therefore be achieved.
Ae~oxding to an expedient practical corif igurativz~. of the method acCOxc9,ii~.g to the invention., use is mad~a o~ a dr~ring cyla.nder or Yat~.kee cylinder provided with reinforcing r~b$ in the irrtex~,or, by which means the lint force produced ~.r~ the preSS rl~.p curl also be increased, substantially above 90 kN,/m. This makes the tissue machine mor~ flexible, iri part~.eular for the ease in vyhich, in addition to the S~facial~~ arid "toilct~~
tissue pap~rs, tissue grades are alSO run in which the "hand feel" and the specific volume (bulk? do ~.ot have the first priority but rather the dryz~ess, that is to pay the praduetivn level..
AS already mentioned, a relatively thin cxeping doctor' ie preferably used. Iri this case, the thickr~.~sa of the ereping doctor taxi in particular be leap than or equal 2o to o.~ mm.
the angle of attack between the tangent to the drying cy2~,nder ar~.d the creping doctor is preferably less Lhar1 or equal to 20°.
Ia the case of this cx'epirig doctor, whet is mown as the "rake angle" cam be in particular gz'eater khan or ecN.al to 15 ° .
3 o According to zhe ~.nven.t~.vra., the obj ect epeca.f ied at the begisxning ia, moreover, achieved by means o~ a machlrie for the produc2~ion of a web of tieeu~ material comprieix~,g a flow box and an ezidless supporting belt, with which the tissue web i,s led through a press nip fos~tned betureen a drying cylinder' arid a~1 opposizlg unit, atzd also comprising a reel-up fox subsequently reeling up the tissue web, the flow box provided being a multilayex flow box, to which at least two stock grades can be supplied, drid means preferably being provided in order to influence in a predefined. way the haxdneps of the reel produced ae the tissue web is reeled up, i~
particular to control and/oz regulate it.
~re~erred embodiirients of the tissue machine according to the invention are specified in the subClaims.
The ,invention w~.ll be e~cplaiz~ed in more detail in the following text by using exmrnplary embodiments and with re~ax~nce to the drawing, in ~.rhieh:
figure s ~hows a schematic illustration of an eXetttplary embodiment of the tieaue machirie accorda.ng to the inventi.On, Figure 2 shows a schematic illustration of an exemplary embodiment of the flow box of the t~.s~us machine according to the invention, Figure 3 shows a schematic parL~.a~, illustration of a creping doctor assigned to the drying cylinder of the tis8ue machine according to the invention, z5 figure 4 shows a eahematia illustration of a conventional reel-up for tissue, figure 5 shows a schematic illustration of~ az~
axcmpla~ry embodiment o~ a real-.up according to the invention, with a spool or reel that can be moved away and~r control, figure 6 shows a schematic ~.J.lustration of a further' etribod~,ment of the reel-up according to the invention belonging to the tissue machine accasding to the inventa.ox~, with a movab~.e spool or reel with associaCed pressure snd/or force censors, _ 7.3 figure 7 shows a graph wh~.eh reproduces the influec.ce of the line force in the winding nip on the specific vo7,ume (bulJc) of the tissue web in the reel, figure B ehoiae a gxaph which, as compared with a suetiort press roll (SPR), reproduces the ix~fluenc~ of a shoe prxss (T~') provided in acpordanoe w~.th the invention on the specific ~srolume (bulb) as a fur~etion of the liz~e force of Lhe press, what is as~,owr~ as a "T_r~.b"
Yankee cylinder, that is to say a Yankee cylinder pxovided with internal reinforcing ribs, b~ing used above 90 kN/m, ~iguxe 9 shows a graph, comparable with the graph Of figure 8, but in this case for the "hand feel", figure 10 shows a graph, comparable with Che graph of figure 8, but in thi9 case for the drxness after the press, figure 11 shows a graph which reproduces the ~.rlfluence ' 25 of drying coz~.ditions such ae, in particular, the dxying ratio between Y'a~.kee cy~.index/$x~yirtg hood, figure 12 shows a graph which reproduces the influence 3 0 of the thieycness of zhe ereplng doctor on the thickzzess of the tissue paper (bulk) , ar~.d ' figure 13 ahowe a graph rahieh r~pxod.~oes the irW~.uerice of the multilayer pxoduc2iox~ of the tissue 35 paper on the specific volume (bulk) ~.n, different presses, it being possible ~.z~
parta,cular to see the advantage resultiTlg from the use of a shoe press (TF) as compared ' w~.th a suction press roll (SPR) .
FigLtz'e 1 shows, in a 9cher~atic illustration, ate a~cemglary embodiment of a tttaehine to according to the z~verrtion for the pxoduation of a tissue web 12_ The tissue machir~e l0 compris~~a a flow bQx 1~ and an endles$ supporting bell 16, with which the tissue v~reb 12 is led through a press r~~.p 22 formed between a drying cylinder 1B, hexe a Yankee cylinder 18, and an opposing unit 20.
The tissue machir~e 20 also comQxises a reel-up 24 for subsequently reeling up the ti$sue web 12.
x5 The flow box 14 provided is a multilayer flow box, in the prepent case a two-layer flew box, to which at least two different stock grades caa be supplied.
Furthermore, nteana described in morn detail Further below are provided in order to influence the hax'driess of the reel produced in a predefinable manner when reeling up the tissue web 12, that is to say in particular to control and/or regulate it. rz~ this case, the line force produced in the winding nip 26 is px'eferably kept below or equal to 0. A kN/m, A former hav~.ng two circulating endless belts 16, 2B is prov~.dec~,, one o~ these two endless ciraulatis~,g belts 6, a8 simultaneously forming the tra~lSporL bell 16.
As can be seen by using figure 1, the two endless belts 16, 28 ru.n togethax, formir~g a stock ir~,let gap 30, in order then to be led over a forming element 32, in particular a formirsg or breapt roll. sn this cafe, the wrap angle with respect Zo the outer belt 28 is smaller than that with reepeat to tea inner supporting belt 16.
zn the pxeseat case, a crescent former is provided.
whose inner belt (supporting belt? Z6 ie formed by a felt.
- 7,5 ZnCO Che il~~.et gap 30 formed between the suppoxtir~,g belt Z6 ax~c~ the outer wire 28, by means of the mulLilayex~ flow box 7.~k, different stock grades, ixi the present ease a stock grade HG~ of sibers made from hardwood and a stock grade 6W of fibers made from poftwood, are introduced_ The fibers m8de of hardwood oazi be, i,n particular, shert fibered chernieal pulps, arzd the fibers made of softwood sari be, ~.n particular, long-fiberad chemical pulps.
After the wrap region of the forGni.rsg roll 32 , the tissue web forming iri 'the process, together with the supporting belt 16, is supplied to tha press nip 22, urhioh is extended in the web runrl~.ng direction L .
8e~ore reaching Chi ex~C~rlded press nip 22, the suppvr~ting belt 16 carry3.r~g the tissue web 12 with it wraps around ari evacu.aLed device, designed here ae a ZO suction roll. 3~, The suction roll. 34 removes a substantial parfi~ of the water from the supporting belt 16 a,nd evexi somewhat from the outer tissue web 12, Tha oppoain.g unit 20 assigned to the drying Cylinder 18 is formed in zhe present case by a shoe press unit, ixs particular a shoe press roll. The press nip Z2 is therefore the ex'Cended press sip of a ahoy press comprising the drying cylinder 18 and shoe press unit 20.
A ereping doctor 4r bar, iz~. par~i.cular a thin craping doctor or bar 36, is assigned to the drying cylinder 1S.
k~ollowa,ng the pxe9s nip 22, the ta,ssue web 12 is led around the drying eyli,nder 18. Tn Lhis case, a drying hood 38 is provided in order to intensify the drying in the relevant wrap region.
As can be seen by us~.F~.g Figure 1, a meaeuriag frame 39 is provided between the drying cylinder 18 and the reel-up 24. In this case, the meaa~red values obtained caz~., for example, also be used for cross-machine profiile regulation, of specific web properties.
In the reel-up 24, the tissue web 12 ie first led over a carrier drum d0 and tJ:~en wound on to a spool 42. zzi this cdse, preferably both the carrier drum 4~0 and the 20 spool 42 ars each assigned a separate drive 44.
As can be sacra by using figure 1. the stock grade HW
made of short .~ibera obtained from hardwood is used for the layer Y facing the surface of the drying cylinder 18, and the stuck grade made of ~.ong fibers obtained ~rom softwood is used for the layer provided on the opposite web side.
Figure 2 shows, in ~. edhematiG illustration, an exemp~a~'y embodiment of the flow box 14 of the tissue ma,ck~,ine according to the inventioz~. In this case, t~,e no~2~e 46 of this flow box 7.4 is at least substantially divided into two chanzxe~,e 50, 5a by a sJ.at 48 extez~ding over the entire machine width. The slat 4B extends outward beyond the nozale 46 a.n the region of the outlet gap 54. The slat length 1z measured staxti,r~,g froTn the turbulez~,ae generator 56 of the flow box 14, just like the nozzle length ll, is therefore greater than the nossle length 11.
Fuxtl~~armox~e, the cross-machir~a disfir~.l~utor pipes 58, 60 for the two s'OOCk grades can be sewn ira, figure 2.
zn Lhe preser~t case, moreover, dilution water 36 rAgulation and/or control sect~.ori by section is p2'ov~.ded o~rer the machine width only for the layer ' facing the forming roll 32 (cf. Eig. l). 1n figure 2, a cross-mach~,ne diatributiors pip~a 61 for dilution grater, for example, can be seen.
xn the region. of the outlet gap 54 of the nozzle 46, one or snore slieeS 62 Cari be provided. I~owerrer, ouch slices are not imperative.
The proportzot~, of the drying contributed by the drying hood 38 to Lhe dxying of the tiesue ~aeb x2 is prefer~ly greater than the pxoportiori of the dry3~g contributed by tY~e dry~,ng cylinder 18.
Figure 3 show, in a schematic partial zlluetration, a creping doctor 36 asszgr~ad to the drying cylinder or Yankee e~r11T1der 18 0~ the tissue machine 10 according to the invention (af. Figure 1).
In the preAerit exemplary embodiment, illustraCed izz figure 3 , Zhe th~,ckncas b of the oreping doctor 36 ~.s l~sa thaz~ or equal to 0 _ 9 mm. The angle of aLLack or clearance angle « between the tangent 76 to th~ dry~.ng cyl~,ader 1.8 passir~g thxough the point os contact 78 arid the creping doctor 36 is lass than or equal to 20~.
The "rake angle" o~ the erep~.z~g dOCLOr 36, desigz~ated "~i" in figure 3, Can ire particular be greater than or equal to 15~.
Figure 4 shows, in a schemar~ic illustration, a conventional real-up 64 for tissue, ~.n which the carrier drum 6B provided wiCh a drive 66 is pressed aga.~,nst the xeel 70 onto which the tissue web produced ~.s wou.~d up, as a result of which the reel 7o is driven. The carriez~ drum 68 is Fixed in position. The reel 7Q can be moved orl rails 72. The pressir~g forc~
must be suffi,ca,aatly high For the necessary drive power to be transmitted. The lira,c forces pxodueed in the winding nip 74 is around 0.8 1~1/m (width) . The line force here is so high that the carriex drum 68 dips into the soft reel '74 and thus destroys ox reduces the specific volume (bulk) . The growth izi the diameter of the reel '70 is ta~Cet~, irate account by moving th~ reel 7Q
away ~xQm the carrier dx~.tm 68 _ Figures 5 a~.c~ 6 show, in a sehet'ri~~~.C illustratioxi, two e~ramplary etribodiments of the reel-up 24 aaaording to the invention.
In the xeepeative reel-up 24, the tisSUe web 12 is ~.cd over a carrier dxum ~k0 and then wound up onto a spool to ~42. Tn both the exemplary embodiments, bath the Caxxier drum 40 and the ppool 42 are each assigned a drive 44.
Between the reel 8 D tormin,g pri the spov~. 42 axed the carrier dx~.m 40, a winding nip or oontact nip 26 is formed, in which a line force is produced which criLica~.ly iafluencep the reaulf,ant winding hardness .
At least the spool 42 can be tTtoved in the x direction, LhaC is to day for example horizora.tally, along rails 82 ox the like.
The embodiment shown in figure 6 of the reel-up 24 is an example o~ a possible solution for the reguJ,acion of the line fioree.
i 25 - In the present case, the carr~.ar drum 4o is mounted in I a, fixed position on the raz.~.s 82. 8y con'Crast, z~.s spool 42 and, ~r~, a cerreaponding way, the reel 80 formed ors the latter can be moved. In this case, the spool 42 can have its position chax~,ged, for example by I mean9 0~ tranalational actuators provided on both i sides, st~.ch a~ threaded rods with associated motor, hydraulic cylinders and so on.
Preferred criteria for the displ$cement of tha spool 42 and the reel b0 formed on the latter are the growth in -' the winding d~.ame'ter D and the line ford in the I winding nip 26.
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In this embodiment, both criter~.a can be satisfied by a control loop, Sensory 63 which nleaeur~ the r~~,p force F in the region 0~ the press rii8 26 directly or indirectly can be integrated in the bearix~gs of the spool ~k2. The aforementioried s?nsox's can be, for example, pressure sensors, force eensoxs, strain gages and so o~n.
lp Fvr ir~.9tar~.co, if the measured toxce diffezs from the predefined force, t~hax is tv say an ap~rvpri.ate des~.~~ed val.u~, then the pxesaure of a relevant hydraulic eylirider, for example, is changed by a controller 84, ~or example via a hydraulic unit, in such a way that ~,5 the d~.~terer~ae between the desired value and the measured value becomes zero.
Of course, a modifieatior~ of this embodiment in which only the Carrier drum ~40 ox both the carrier drum 40 2d ancj. the epoo~. 42 can be moved or displaced is also eoneeiva~le. Zn the case of a movable aarr~.Ar dxum 40, the latter has the relevant sez~sors via which the r~,ip force R ,is regulated.
25 The reel displacement in this case only compensates for the grov,rth ire the reel diameter D .
The distance between Lhe axes of the carrier drum 40 and of the spool 42 or o~ the reel A0, which is 30 iz~creasingly enlarged during the winding opexatio~,, is designated "A" in figure 6.
rn the c~ae of lower line forces and large. heavy reels, it is poss~.b~.e t4r the cage to occur in which 35 tha measurement accuracy of the sensors and the s~ttiz~.g accuracy (fr~.eziotl) are r~o longer adequate.
I11 parLiculax in the case o~ line forces in the winding nip 36 vrhieh are less than or equal tv 0.5 kN/m and in paxt~,cul,ar Less than or equal tv p . 2 krT/m, fox example the movable spool and, ire. a ooxxespor~ding way, the reel 80 formed on the later are preferably designed such that xhey can be moved away under control. The embodiment shown ~.n figure 5 cvn.cerna a corresponding desigxi.
The mee~aured variables provided fox this away movement under cora.tro7. are, in particular, the following 1.0 variables - diameter D cf the reel 84 - 8osition of the z-eel 80 or of the spool 42 r~lative to the carrier drum 40.
Ire this vase, the position of the reel 80 Ca.ri be meaSUred, fvr example, by means of aeasors such as i L'~'DTs (linear variable differential transformers), and Lhe diameter of the reel, c~,n be determined by a a0 distance sensor, fox example optically or acoustically.
The actuators 86 (cf, figure 6), which van be hydraulic cylinders arid so on, for example, position the reel so ' accurately such that the latter just touches the carrier drum 4 D , for example . In this case, the liza.e force FL produced izz the w~.nding nip 26 is therefore equal tc~ zero. Tf FL ~ 0 kN/m ~.s to be the case, tln.er~
the reel. 80 can be moved further orito the carr~.cx drum ao by a predefined distance which, ~.n particular, dep~rid~ on the softness o~ the reel 80. Therefore, a slight desired pressure in the press rip ar coritact nip 26 0~, for example, F~, s O.a kN/m is produced. The distance A (ct. also figure 6) is therefore ~, c d/2 ~- D/2 or A ~ d/2 + D/2 - x, ~rhsre ~~x~~ is the measure of how far the Carrier drum 40 dips into the reel BO formed on the spool ~2.
A ~urther possible way of monitoring and setting Lhe nip forco ree~~ilt~, fox 2xa~lple, from Lhe observation of the nip region with a CCD camera. Us~.ng Zhe Ia,LLer, in partiaul.ar the distance between the Carrier drum 40 arid the reel BO c~tn be measured. and displayed. Hy using ari appropriate evaluatioT7, of the itrtage obtained, a desired value, for example for a hydraulic cylinder pressure.
can again be calculated and, via a control device, can effect the displacement as far as the desired distance or nip force _ The bulb gain lies in a range from ~ to 8%.
Zr~ order to illustrate the outws.xd movement control, iri the illustration according to figure 5 the spool 42 is aa~igned a poir~t.er 98, whose position with respect Lo a stationary scale 90 ultim2.Cely ~.ndicates the poeitioz~
of the spool. 42 and therefore aE the reel 80 formed on the latter.
Furthermore, i~. figu,re 5 it is posa~.ble to see a ssr~aor 92, which can iz~ particular be a serisOr of the aforementio~ted type, for example only a CCD camera or the like.
F~,gure 7 shows a graph. which reproduces the ir~,fluen.ce of the line force LF in the wir~ding rxip ors. the specific voJ.ume (bulk) cf the tissue web in Lhe reel. "HW"
desigTlates a stock grade of fibers made from harduraad axzd. "SWp c~eeigr~,ates a stock grade of fibers made from softwood.
Figure 8 shows a graph which, is Comparison with a auction press roll (SPR) , r2pt'oduce~ the in~luezice of a shoe press (TF) provided in accordance vuith the ~.nveation on the specific volt~~e (bulk) as a function of the lir~,e force of the press. In this case, begizzning at 90 kN/m, what is known as s "T-xib~~ Yankee cylirsder, 'that is to say a Yankee eylindeX provi~,ed with ~.nterna7, reinforcing jibs, zs used.
_ 22 Figure 9 shows a graph that is comparable with the graph of figure 8, but in this ease fer the "hand feel"
alread~r mentioned az the beginning.
zn addition, figure 20 again, shows a graph that ~.s comparable with th,e graph of figure 8, but fn this case for Lhe dryness after the press.
The graph of figure ~.1 reproducQa the in~luenca of dx~ring cond~.tiona, such as in particular the r3rying raL~.o Yankee cylinder/drying hood.
The graph o~ figure 12 shows the influenoe o~ the thiaknass~ of the ereping doctor on the thickness of the Z5 tissue p~.per, which here corxesponda to the ppecific volume (bulk). on the other hand, an improved "hand feel" value is also possible ac a constant "bulk"' val~a. 2n the graph, the abbreviation ~GMT'~ stands for the expression "geometric mean ter~eile strength".
Figure Z3 shows a graph which reproduces the in fluanee ef the multilayer production of the tissue paper on the specific volume (bulk) is the case of differez~.t presses, it being possible to nee in particular the advantage re~ul~,ir~g from the use of a shoe press (Tk') as compared with a sueL,ion press roll (SpR).
Kist of deli uationa ~.0 Ta.ssue machine 12 Ti9sue web 14 Flow box 16 Endlcas circulating belt, support~.ng belt 18 Drying cylinder. Yankee cylizlc~er 20 Oppor~ing unit, Whoa press u~,it 22 Press nip, contact nip 24 Re~l,up 26 winding niP
28 ~Indless oiraulating belt, outer wire 30 Stock inlet gap i . 32 Forming element, forming X011, breast roll 34 Evacuated device, suction roll 36 Creping doctor, doctor bar 38 Drying hood 39 Measuring gams ' 40 Carrier drum 42 8poo1 44 Drive 46 Nozzle 4B Slat I
0 Chansze 1 52 Charmel 5a Outlet gap 56 'I'u~bulence generator 58 Croas-maehixle distribution pipe 60 Crvrs-machine distribution pipe 61 cross-machine distribution pipe 62 slice 64 Reel-up 66 Drive 68 Carrier drum ' 70 Reed.
72 Rails i 74 Winda.ng nip 7 6 Tangent 7g k~oint of contact 90 Reel 82 Rails 83 Sensor 84 Contro~.ler 86 3~etuator 88 Pointer 90 Seale 92 8era.sor A 'Distance D Reel d~.ameter F Nip force, force in the Winding rii8 b Thickness ly Nozzle length 1, Slat length ,An.gle of attack, clearance angle ~i 'Rake angle°
A high-temperature hood Can be provided, above the dx'y~.ng cylinder or Yankee cyl~.nder.
A further improvenletzt ire the tissue product properties can else be achieved in parL~.cular by the tise~.e web being doctored off the drying cylinder by means oL a crepi~g doctor, ~.n parLiCUlar a th~.n crep~.ng doctox.
one or more of the following stock grades ~.a preferably used:
- fibers made ox haxdwood, in particular short-fiber chemical. pulps ' 20 - fibers made of softwood, in particular long-fiber ' chemical pulps - CTMP (chemiC~l-thermojnechaaical pulp).
r Prefereriee is given. to stock grace mixtures in which the proportion of fibers made of hazdwood lies in a I range from about 50% to about BO~S, the proportion of ~ibere made of softwood lies in a range from about 20%
to abou'G 50% and/or the proportion of CTMQ (chemzcal thermomeahanical pulp) lies iz~ a range from 0% to about 20%.
Tht~e, amongst others, for example the following stock grad~ mixtures are conceivable:
Ex. "a" Ex. "b" Ex. "a~.
I Hardwood (50 to 80%) 50 60 Softwood (20 t0 50%) 30 40 20 CTMP (0 to 20k) 20 0 10 I
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~z~ this case, in particular the C'fflP in a respective stock grade mixture ~,mpro~cres the specific volume (bulk) According to a preferred pract~.ca1 configuration of the method accordir~g to th~ invantion, the LisSue web is led around the drying cy~.inder after the press nip, the drying in the x~levant wrap region preferably being intensified by a drying hood, in partivular a high t~ntpera.ture hood.
2t is of particular advantage it Lhe Tnultilayer flow box is supplied with eat least two differer~t stQCk grades axed in this case for short fibers obtained from hardwood LO be used fox the layer of the t~.ssue zueb that faces tha dryiz~.g cylinder surface and for l.oag fibers 4bxained fzorn softwood to be used far the layer on the opposite side of the web, It is also of advantage in particular if the ~low box i~ loaded with at least two layers with different fibrous stocks, the stock with the short fibers obtained from hardwood being add~d into the layer of th~ flocu bo~c which forms the Side of the tissue web Z5 that faced the drying ox Yankee cylinder surface. The second layer is exped~.ently loaded with long fibers made Pram softwood. Alterr,~atively or additiozially, ' this second layer Can also be loaded with ~.oz~,g ~sbera and C'~tF and/or with long Fibers and CMF arid short 3o fibers. Th~.s layer forms the second layer of the tissue web, which faces the drying hood in the drying process. Tt therefore never comes into contact with i the dryixig or Yankee cylinder surface. Using these i method Steps, Che "hand f~cl"' and ~~bulk" values are 35 improved by s.bout 5~ and more.
Use i~ preferably made of a multilayer flow box, who~sa nozzle is subdivided into at leapt two channels by mews of at least one slat extending over the entzre .l f rnaehine~ width. zn this case, the nozzle is expedieritl.y subd~.vided at least s,.a.batantially symtt~etrieally into two charu~,els by a slat .
Particular~,y good results are achieved if the slat exter~.ds outward beyond the noazle in the region of the outlet gap. This counteracts any mixing of the plies.
Advantageously, uSe can be rilaCle of a flow box havi~,g l0 dilution water regulation and/or control section by section ever the machine width, in order to be able to set a respectively desir~d cross-machine grammage prof i~,e _ xn specific cases i,t ~.s advaritagevus if in each vape dilut~.on w~.t~r regu~,ation and/or contrel is provided fcr at least Lwo Layers. P'or example, when a two-layer flow box is used, in each case dilution water' regulation or control can therefore be provided in both layers. if appropriate.
Dilution water regulation ar~d/or control is preferably provided at least in the layez~ facir~.g the forming ox breast roll. In this case, appropriate dilution water regulation and/or control can in particular be providBd only for this one layer, that is to say the outer layer with, respect to the foaming or breast roll. The forming or breast roll can be closed, open yr else evacuated.
The drying of the web by the drying or 'S.'ar~.kee cylir~.der and a drying or hat-air hood is important for the drying process, aacorc~ir~,g to a preferred practical oonfiguration of the method accord~.ng to the invez~tlon, the proportion, of th~ drying contributed by the dx'Yirlg h4od to the drying of the tissue web being choacn tv be greater than the proportion of the drying Con'~z'ibuted by the drying cylinder.
Tn this case, the ratio between the propoz~t~.on o~ the drying from the dxyi~g hood and the proportion of zhe drying from the 8rying cylinder is advantageously chosez~ to be gre~.ter than 55:e~5, in pat'ticul8r greater than or equal 'to 60:80, in particular greater than or equal to 65 ; 35 and preferably greater than Or equal to 7a:3o_ The drying hood is pxefexa,bly operated at a t~mperature ZO which is gxeater than. or equal to 400°C, in par'Cicular gxeater Lhari or equal to 500°C, in particular greater than ox equal to 600aC and preferably greaLex than or equal to 700°C.
The steajn pressure in the dxY~.ng cylinder oan additionally be reduced_ For example, for Lhe steam pressuxe in the drying cylinder, a value is advaatageov.a.sly chosen which is less than Or equal zo 0.7 MPa, in particular lea9 than or equal to 0.6 M8a ar~.d preferably leSS than or ec~tlal zo 0.5 MFa.
As a result, the course of the drying can be raised further. By mea.a~a of the aforementioned rrieasurea, an increase in the "bulk" value by up to 5~ and an improvement xn the "hand feel" value are achiev~ed_ Particulax importance is also attached to wizZding vp the t~.~sue web at the ehd ofi 'Che tissue machine.
3o According to a pxeterred practical configuration of the method according to the invention, a re~1-up ~.s used in which the tissue web is led over a carrier drum and is then wound up onto a spool, in each case a drive prefera~?1y being assigned both. to the carrier drum and to the spool. As a xesult, optimum reeling of zhe web is achieved, without destroying the specific volume bulk) of the paper web produced. Thus. with the use of two d~-zves for the carriex drum arid the spool or the real, in partscular a reductivr~. of the line Force produced in the winding nip ig possible_ Accvrd$rig to an expedient practical eoti~iguraLior~, of the method according Lo Lhe invex~tion, the line tome produced in the winding nip between the earriex drum and the spool is cho~an to be leas thar~ or equal. to 0.B kN/m, in particular less than or equal to 0.5 kN/m and preferably leas thax~ car equal, to 0.2 k1Q/m. Since ID no drive power has to be transmitted betweetl the carriex' drum and the reel, the pressure in the minding nip ox contact nip can be reduced.
6inae tiesue paper is creped. exhibits high eLretch, Z5 that ~,S to Say a high mvdulus of elapticity, and has a loW tensile strength, ne substantial web Lension can be applied in order to ixlcreaae the wir~ding hardaese of the reel.
20 The maximum difference between the cizcumferera,ti~l speed of Lhe reel a~.d th,e c~,xcumterential speed of the carrier roll is preferably less 'Chan 10~ of the eircumferential speed of the earriex roll.
25 According to a preferred pxaatical eorifigura.tion of the method according to the irlveriCioz~., the web tension between the drying cylinder and the carrieY drum is eet, in partiCU~.a~' Controlled and/or regulated, to a pzedefinable desired value via the drive assigned Co 30 the carrier dxuril. ~.zldependently of the line force produced in thn winding n.ip.
on aocourst o~ the crapxr,~g at the ere~7ir~,g doctor, the carrier drum eircumferential speed is lower than the 35 ciroumferential speed of the drying cylinder.
The drive assigned to the spool is advantageously coritx~Qlled and/or xogulated as a function of the speed of the carrier drum.
a -O~ particular zxnportanoe during the production of a.
' soft reel is the control of the "low" line force iii the windir~g nip or eoz~.taet axp. According to a preferz~ed practi,eal configuration of the method according to the lliveritiOT7,, a reel-up is used for this purpose iri which the carrier drurit is mounted in e~ f fixed poe~.tioa and the spool can be moYee~- Accordingly, the growth in the reel diameter ea~1 be compensated for bar means of to appropriate movement o~ the ~poal. In addi'Cian, the line force iz1 xhe winding nip ca,n be set i.n the desired mannex via the mo~crable spool. Ix1 order to compensate for the gXOwth in di~.meter of the reel and in order to set the line ~oroe ix1 the winding rllp, a ComTnon cvntxol loop cars advantageously be used. One expedient configuration of the method aCCOrdirig to the invention ie distinguished bar the fact that. the lin~ foxes in the winding n~.p is determined via a'C leaSZ one force sensor an,d Lh~.s line ~oroe is regulated by means of appropriate moo~ment of the Spool. In priz~ciple, however, for example the spool cax~ also be fixed iri position and the carrier druril can be movable.
Fuzthex~more, such designs ~.n which bath the carrier drum arlq~ the spool Carx respectively be moved are also Z5 conceivable.
~t ~.s possible that the measuxsment accuracy Ot Lhe aera.sors and the setting accuracy (friction) ie no t longer sufficient at iota line foroeQ anal with large, i 30 heavy reels. Iri particular iT1 the cane of line forces in the windir~g nip which are less than or eBual 'Co ' 0.5 kN/m arid in particular less thar~ or equal to 0.2 kN/m, the movable spool is therefore preferably moved away under Control. xr~ this case, the measured 35 vaxiablee used for the moveme~lt away uz~der control can I
in particular be the reel diameter and the position of the spool or the real formed thereon. relative tv the carr~,er drum.
_ g _ Rccord~,~.g to a fuxther advancagevua coxr~~.guratxon of the ~ethvd according to the invention, in order to set, contra. and/or regulate the line farce in the winding nip, the region, of the winding nip can be monitored appropriately by means O~ a CCD camera. Ira. this case, by means of the CCD camera, preferably the reSpeczive distance betweeTl the Carrier dru,t~c~ arid the spool ox the reel Formed oxa. the latter is registered. With such observation of the winding nip region, for example by meaza,~ of a CCD camera, the result is therefore a further possibility o~ monitoring anal setting the winding force. Tt is therefore possible to measure allc~.
display the di~st~nee between the carrier drum sad the reel, . 8y u~si,rng az~. evaluation of the image, it is then again posaib7,e Lo reach a desired value of the hydraulic cylinder pxessure that influences the mo~'able reel arid, via a control device, to execute the i displacement or shift as far as the desired distance or wizld.~.rig force . The gain in bulk can lie, for example, in a rax~.ge From 4 to 8~ . R further advantage is that the "bulk" gain achieved by the Shoe press ie not destroy~d, and therefore the quality of the Web is maintained.
It is also of advara,tage if th.a drive assigned to the ' spool and therefore to the reel i~ rlot changed during the winding operation, that ie to say in part~.cular not when the anew spool is moved beyond th,e primary or winding start position,, in. which tie drive is coupled 3o up and the s8ool is accelerated, to the secondary position on the rails. Controlled winding from start to end therefore results.
The paper qualify can be increased f~.rther by the mesa par unit. ar~a of th.~ tissue ~casb in the uncreped state lying in a range front about 11 g/mo to about 20 g/m~
and a.n t~~ creped state lying in a range from about 14 I g/m'to about 24 g/m~.
- l~ -since, above all in the case of thin papers and ire particular ire, the case of "facial tissue" arid "toilet"
tissue, the formation, that iS Lo say uniformity of the fiber arrangement, playa as important role, the use of s a crescent former is of pdr~icular advantage in these cases in particular. Ts~ this ease, the Web is dawatered, transported, pressed and passed on to the drying cylinder or Yar~kee oylindex an a felt. At Lhe start of dewatexing, an outer ror~.re is still provided.
l0 In addition to improved formation, the result iS also improved strength with possible MD/CMD breakir~g length ratios of 1:1 to 4:1. This ma)Ces it possible to beat the fibers less. This increases the "hulk~~ value. Hy meazl.a of this former 'type, "strength" sari be converted 15 into "bulk". This former typo improves the ppeeifia vvlu~~ ~bulJt) by + 5~ in combination with at least one of the design variants described.
In this case, use can be made in particular of a 20 crescent former, iahose inner or supporting bell, formed by a fell, together with the tissue web, is led over at J.eaet one evacuated device in the Web running direct~,on before 'Che press nip. The evacu4.ted device provided can be, in particular, a suction, roll. As already 25 mentioned, the outer belt provided in the region of the forging el~ment of the crescent former can be formed in particular by a meth belt (wire).
Also of particul,ax advantage, in particular, is the use 30 of a shoe press with a shoe length as measured iz~. the web ria,nn~.ng dixnction of greater thars ox ~quaZ to BD mm and preferably greater than or equal tv 12o mm. ~y means of the shoe press, a lixla force which lies the range from 60 kN/m Lo about 90 kN/m is preferably 35 produced, The maximum pressing pressure in Lhe pXess nip of the shoe px'eSS ils preferably leas than or egual Co 2 bar arid preferably less than or equal to 1.5 bar.
Moreover, the shoe press can comprise a shoe press unit ~rith a blind-drilled press cover. As co~pared wish a suction press roll, a, bulk gain in a rar~.ge from about 15$ to about 20~ oan therefore be achieved.
Ae~oxding to an expedient practical corif igurativz~. of the method acCOxc9,ii~.g to the invention., use is mad~a o~ a dr~ring cyla.nder or Yat~.kee cylinder provided with reinforcing r~b$ in the irrtex~,or, by which means the lint force produced ~.r~ the preSS rl~.p curl also be increased, substantially above 90 kN,/m. This makes the tissue machine mor~ flexible, iri part~.eular for the ease in vyhich, in addition to the S~facial~~ arid "toilct~~
tissue pap~rs, tissue grades are alSO run in which the "hand feel" and the specific volume (bulk? do ~.ot have the first priority but rather the dryz~ess, that is to pay the praduetivn level..
AS already mentioned, a relatively thin cxeping doctor' ie preferably used. Iri this case, the thickr~.~sa of the ereping doctor taxi in particular be leap than or equal 2o to o.~ mm.
the angle of attack between the tangent to the drying cy2~,nder ar~.d the creping doctor is preferably less Lhar1 or equal to 20°.
Ia the case of this cx'epirig doctor, whet is mown as the "rake angle" cam be in particular gz'eater khan or ecN.al to 15 ° .
3 o According to zhe ~.nven.t~.vra., the obj ect epeca.f ied at the begisxning ia, moreover, achieved by means o~ a machlrie for the produc2~ion of a web of tieeu~ material comprieix~,g a flow box and an ezidless supporting belt, with which the tissue web i,s led through a press nip fos~tned betureen a drying cylinder' arid a~1 opposizlg unit, atzd also comprising a reel-up fox subsequently reeling up the tissue web, the flow box provided being a multilayex flow box, to which at least two stock grades can be supplied, drid means preferably being provided in order to influence in a predefined. way the haxdneps of the reel produced ae the tissue web is reeled up, i~
particular to control and/oz regulate it.
~re~erred embodiirients of the tissue machine according to the invention are specified in the subClaims.
The ,invention w~.ll be e~cplaiz~ed in more detail in the following text by using exmrnplary embodiments and with re~ax~nce to the drawing, in ~.rhieh:
figure s ~hows a schematic illustration of an eXetttplary embodiment of the tieaue machirie accorda.ng to the inventi.On, Figure 2 shows a schematic illustration of an exemplary embodiment of the flow box of the t~.s~us machine according to the invention, Figure 3 shows a schematic parL~.a~, illustration of a creping doctor assigned to the drying cylinder of the tis8ue machine according to the invention, z5 figure 4 shows a eahematia illustration of a conventional reel-up for tissue, figure 5 shows a schematic illustration of~ az~
axcmpla~ry embodiment o~ a real-.up according to the invention, with a spool or reel that can be moved away and~r control, figure 6 shows a schematic ~.J.lustration of a further' etribod~,ment of the reel-up according to the invention belonging to the tissue machine accasding to the inventa.ox~, with a movab~.e spool or reel with associaCed pressure snd/or force censors, _ 7.3 figure 7 shows a graph wh~.eh reproduces the influec.ce of the line force in the winding nip on the specific vo7,ume (bulJc) of the tissue web in the reel, figure B ehoiae a gxaph which, as compared with a suetiort press roll (SPR), reproduces the ix~fluenc~ of a shoe prxss (T~') provided in acpordanoe w~.th the invention on the specific ~srolume (bulb) as a fur~etion of the liz~e force of Lhe press, what is as~,owr~ as a "T_r~.b"
Yankee cylinder, that is to say a Yankee cylinder pxovided with internal reinforcing ribs, b~ing used above 90 kN/m, ~iguxe 9 shows a graph, comparable with the graph Of figure 8, but in this case for the "hand feel", figure 10 shows a graph, comparable with Che graph of figure 8, but in thi9 case for the drxness after the press, figure 11 shows a graph which reproduces the ~.rlfluence ' 25 of drying coz~.ditions such ae, in particular, the dxying ratio between Y'a~.kee cy~.index/$x~yirtg hood, figure 12 shows a graph which reproduces the influence 3 0 of the thieycness of zhe ereplng doctor on the thickzzess of the tissue paper (bulk) , ar~.d ' figure 13 ahowe a graph rahieh r~pxod.~oes the irW~.uerice of the multilayer pxoduc2iox~ of the tissue 35 paper on the specific volume (bulk) ~.n, different presses, it being possible ~.z~
parta,cular to see the advantage resultiTlg from the use of a shoe press (TF) as compared ' w~.th a suction press roll (SPR) .
FigLtz'e 1 shows, in a 9cher~atic illustration, ate a~cemglary embodiment of a tttaehine to according to the z~verrtion for the pxoduation of a tissue web 12_ The tissue machir~e l0 compris~~a a flow bQx 1~ and an endles$ supporting bell 16, with which the tissue v~reb 12 is led through a press r~~.p 22 formed between a drying cylinder 1B, hexe a Yankee cylinder 18, and an opposing unit 20.
The tissue machir~e 20 also comQxises a reel-up 24 for subsequently reeling up the ti$sue web 12.
x5 The flow box 14 provided is a multilayer flow box, in the prepent case a two-layer flew box, to which at least two different stock grades caa be supplied.
Furthermore, nteana described in morn detail Further below are provided in order to influence the hax'driess of the reel produced in a predefinable manner when reeling up the tissue web 12, that is to say in particular to control and/or regulate it. rz~ this case, the line force produced in the winding nip 26 is px'eferably kept below or equal to 0. A kN/m, A former hav~.ng two circulating endless belts 16, 2B is prov~.dec~,, one o~ these two endless ciraulatis~,g belts 6, a8 simultaneously forming the tra~lSporL bell 16.
As can be seen by using figure 1, the two endless belts 16, 28 ru.n togethax, formir~g a stock ir~,let gap 30, in order then to be led over a forming element 32, in particular a formirsg or breapt roll. sn this cafe, the wrap angle with respect Zo the outer belt 28 is smaller than that with reepeat to tea inner supporting belt 16.
zn the pxeseat case, a crescent former is provided.
whose inner belt (supporting belt? Z6 ie formed by a felt.
- 7,5 ZnCO Che il~~.et gap 30 formed between the suppoxtir~,g belt Z6 ax~c~ the outer wire 28, by means of the mulLilayex~ flow box 7.~k, different stock grades, ixi the present ease a stock grade HG~ of sibers made from hardwood and a stock grade 6W of fibers made from poftwood, are introduced_ The fibers m8de of hardwood oazi be, i,n particular, shert fibered chernieal pulps, arzd the fibers made of softwood sari be, ~.n particular, long-fiberad chemical pulps.
After the wrap region of the forGni.rsg roll 32 , the tissue web forming iri 'the process, together with the supporting belt 16, is supplied to tha press nip 22, urhioh is extended in the web runrl~.ng direction L .
8e~ore reaching Chi ex~C~rlded press nip 22, the suppvr~ting belt 16 carry3.r~g the tissue web 12 with it wraps around ari evacu.aLed device, designed here ae a ZO suction roll. 3~, The suction roll. 34 removes a substantial parfi~ of the water from the supporting belt 16 a,nd evexi somewhat from the outer tissue web 12, Tha oppoain.g unit 20 assigned to the drying Cylinder 18 is formed in zhe present case by a shoe press unit, ixs particular a shoe press roll. The press nip Z2 is therefore the ex'Cended press sip of a ahoy press comprising the drying cylinder 18 and shoe press unit 20.
A ereping doctor 4r bar, iz~. par~i.cular a thin craping doctor or bar 36, is assigned to the drying cylinder 1S.
k~ollowa,ng the pxe9s nip 22, the ta,ssue web 12 is led around the drying eyli,nder 18. Tn Lhis case, a drying hood 38 is provided in order to intensify the drying in the relevant wrap region.
As can be seen by us~.F~.g Figure 1, a meaeuriag frame 39 is provided between the drying cylinder 18 and the reel-up 24. In this case, the meaa~red values obtained caz~., for example, also be used for cross-machine profiile regulation, of specific web properties.
In the reel-up 24, the tissue web 12 ie first led over a carrier drum d0 and tJ:~en wound on to a spool 42. zzi this cdse, preferably both the carrier drum 4~0 and the 20 spool 42 ars each assigned a separate drive 44.
As can be sacra by using figure 1. the stock grade HW
made of short .~ibera obtained from hardwood is used for the layer Y facing the surface of the drying cylinder 18, and the stuck grade made of ~.ong fibers obtained ~rom softwood is used for the layer provided on the opposite web side.
Figure 2 shows, in ~. edhematiG illustration, an exemp~a~'y embodiment of the flow box 14 of the tissue ma,ck~,ine according to the inventioz~. In this case, t~,e no~2~e 46 of this flow box 7.4 is at least substantially divided into two chanzxe~,e 50, 5a by a sJ.at 48 extez~ding over the entire machine width. The slat 4B extends outward beyond the nozale 46 a.n the region of the outlet gap 54. The slat length 1z measured staxti,r~,g froTn the turbulez~,ae generator 56 of the flow box 14, just like the nozzle length ll, is therefore greater than the nossle length 11.
Fuxtl~~armox~e, the cross-machir~a disfir~.l~utor pipes 58, 60 for the two s'OOCk grades can be sewn ira, figure 2.
zn Lhe preser~t case, moreover, dilution water 36 rAgulation and/or control sect~.ori by section is p2'ov~.ded o~rer the machine width only for the layer ' facing the forming roll 32 (cf. Eig. l). 1n figure 2, a cross-mach~,ne diatributiors pip~a 61 for dilution grater, for example, can be seen.
xn the region. of the outlet gap 54 of the nozzle 46, one or snore slieeS 62 Cari be provided. I~owerrer, ouch slices are not imperative.
The proportzot~, of the drying contributed by the drying hood 38 to Lhe dxying of the tiesue ~aeb x2 is prefer~ly greater than the pxoportiori of the dry3~g contributed by tY~e dry~,ng cylinder 18.
Figure 3 show, in a schematic partial zlluetration, a creping doctor 36 asszgr~ad to the drying cylinder or Yankee e~r11T1der 18 0~ the tissue machine 10 according to the invention (af. Figure 1).
In the preAerit exemplary embodiment, illustraCed izz figure 3 , Zhe th~,ckncas b of the oreping doctor 36 ~.s l~sa thaz~ or equal to 0 _ 9 mm. The angle of aLLack or clearance angle « between the tangent 76 to th~ dry~.ng cyl~,ader 1.8 passir~g thxough the point os contact 78 arid the creping doctor 36 is lass than or equal to 20~.
The "rake angle" o~ the erep~.z~g dOCLOr 36, desigz~ated "~i" in figure 3, Can ire particular be greater than or equal to 15~.
Figure 4 shows, in a schemar~ic illustration, a conventional real-up 64 for tissue, ~.n which the carrier drum 6B provided wiCh a drive 66 is pressed aga.~,nst the xeel 70 onto which the tissue web produced ~.s wou.~d up, as a result of which the reel 7o is driven. The carriez~ drum 68 is Fixed in position. The reel 7Q can be moved orl rails 72. The pressir~g forc~
must be suffi,ca,aatly high For the necessary drive power to be transmitted. The lira,c forces pxodueed in the winding nip 74 is around 0.8 1~1/m (width) . The line force here is so high that the carriex drum 68 dips into the soft reel '74 and thus destroys ox reduces the specific volume (bulk) . The growth izi the diameter of the reel '70 is ta~Cet~, irate account by moving th~ reel 7Q
away ~xQm the carrier dx~.tm 68 _ Figures 5 a~.c~ 6 show, in a sehet'ri~~~.C illustratioxi, two e~ramplary etribodiments of the reel-up 24 aaaording to the invention.
In the xeepeative reel-up 24, the tisSUe web 12 is ~.cd over a carrier dxum ~k0 and then wound up onto a spool to ~42. Tn both the exemplary embodiments, bath the Caxxier drum 40 and the ppool 42 are each assigned a drive 44.
Between the reel 8 D tormin,g pri the spov~. 42 axed the carrier dx~.m 40, a winding nip or oontact nip 26 is formed, in which a line force is produced which criLica~.ly iafluencep the reaulf,ant winding hardness .
At least the spool 42 can be tTtoved in the x direction, LhaC is to day for example horizora.tally, along rails 82 ox the like.
The embodiment shown in figure 6 of the reel-up 24 is an example o~ a possible solution for the reguJ,acion of the line fioree.
i 25 - In the present case, the carr~.ar drum 4o is mounted in I a, fixed position on the raz.~.s 82. 8y con'Crast, z~.s spool 42 and, ~r~, a cerreaponding way, the reel 80 formed ors the latter can be moved. In this case, the spool 42 can have its position chax~,ged, for example by I mean9 0~ tranalational actuators provided on both i sides, st~.ch a~ threaded rods with associated motor, hydraulic cylinders and so on.
Preferred criteria for the displ$cement of tha spool 42 and the reel b0 formed on the latter are the growth in -' the winding d~.ame'ter D and the line ford in the I winding nip 26.
I
In this embodiment, both criter~.a can be satisfied by a control loop, Sensory 63 which nleaeur~ the r~~,p force F in the region 0~ the press rii8 26 directly or indirectly can be integrated in the bearix~gs of the spool ~k2. The aforementioried s?nsox's can be, for example, pressure sensors, force eensoxs, strain gages and so o~n.
lp Fvr ir~.9tar~.co, if the measured toxce diffezs from the predefined force, t~hax is tv say an ap~rvpri.ate des~.~~ed val.u~, then the pxesaure of a relevant hydraulic eylirider, for example, is changed by a controller 84, ~or example via a hydraulic unit, in such a way that ~,5 the d~.~terer~ae between the desired value and the measured value becomes zero.
Of course, a modifieatior~ of this embodiment in which only the Carrier drum ~40 ox both the carrier drum 40 2d ancj. the epoo~. 42 can be moved or displaced is also eoneeiva~le. Zn the case of a movable aarr~.Ar dxum 40, the latter has the relevant sez~sors via which the r~,ip force R ,is regulated.
25 The reel displacement in this case only compensates for the grov,rth ire the reel diameter D .
The distance between Lhe axes of the carrier drum 40 and of the spool 42 or o~ the reel A0, which is 30 iz~creasingly enlarged during the winding opexatio~,, is designated "A" in figure 6.
rn the c~ae of lower line forces and large. heavy reels, it is poss~.b~.e t4r the cage to occur in which 35 tha measurement accuracy of the sensors and the s~ttiz~.g accuracy (fr~.eziotl) are r~o longer adequate.
I11 parLiculax in the case o~ line forces in the winding nip 36 vrhieh are less than or equal tv 0.5 kN/m and in paxt~,cul,ar Less than or equal tv p . 2 krT/m, fox example the movable spool and, ire. a ooxxespor~ding way, the reel 80 formed on the later are preferably designed such that xhey can be moved away under control. The embodiment shown ~.n figure 5 cvn.cerna a corresponding desigxi.
The mee~aured variables provided fox this away movement under cora.tro7. are, in particular, the following 1.0 variables - diameter D cf the reel 84 - 8osition of the z-eel 80 or of the spool 42 r~lative to the carrier drum 40.
Ire this vase, the position of the reel 80 Ca.ri be meaSUred, fvr example, by means of aeasors such as i L'~'DTs (linear variable differential transformers), and Lhe diameter of the reel, c~,n be determined by a a0 distance sensor, fox example optically or acoustically.
The actuators 86 (cf, figure 6), which van be hydraulic cylinders arid so on, for example, position the reel so ' accurately such that the latter just touches the carrier drum 4 D , for example . In this case, the liza.e force FL produced izz the w~.nding nip 26 is therefore equal tc~ zero. Tf FL ~ 0 kN/m ~.s to be the case, tln.er~
the reel. 80 can be moved further orito the carr~.cx drum ao by a predefined distance which, ~.n particular, dep~rid~ on the softness o~ the reel 80. Therefore, a slight desired pressure in the press rip ar coritact nip 26 0~, for example, F~, s O.a kN/m is produced. The distance A (ct. also figure 6) is therefore ~, c d/2 ~- D/2 or A ~ d/2 + D/2 - x, ~rhsre ~~x~~ is the measure of how far the Carrier drum 40 dips into the reel BO formed on the spool ~2.
A ~urther possible way of monitoring and setting Lhe nip forco ree~~ilt~, fox 2xa~lple, from Lhe observation of the nip region with a CCD camera. Us~.ng Zhe Ia,LLer, in partiaul.ar the distance between the Carrier drum 40 arid the reel BO c~tn be measured. and displayed. Hy using ari appropriate evaluatioT7, of the itrtage obtained, a desired value, for example for a hydraulic cylinder pressure.
can again be calculated and, via a control device, can effect the displacement as far as the desired distance or nip force _ The bulb gain lies in a range from ~ to 8%.
Zr~ order to illustrate the outws.xd movement control, iri the illustration according to figure 5 the spool 42 is aa~igned a poir~t.er 98, whose position with respect Lo a stationary scale 90 ultim2.Cely ~.ndicates the poeitioz~
of the spool. 42 and therefore aE the reel 80 formed on the latter.
Furthermore, i~. figu,re 5 it is posa~.ble to see a ssr~aor 92, which can iz~ particular be a serisOr of the aforementio~ted type, for example only a CCD camera or the like.
F~,gure 7 shows a graph. which reproduces the ir~,fluen.ce of the line force LF in the wir~ding rxip ors. the specific voJ.ume (bulk) cf the tissue web in Lhe reel. "HW"
desigTlates a stock grade of fibers made from harduraad axzd. "SWp c~eeigr~,ates a stock grade of fibers made from softwood.
Figure 8 shows a graph which, is Comparison with a auction press roll (SPR) , r2pt'oduce~ the in~luezice of a shoe press (TF) provided in accordance vuith the ~.nveation on the specific volt~~e (bulk) as a function of the lir~,e force of the press. In this case, begizzning at 90 kN/m, what is known as s "T-xib~~ Yankee cylirsder, 'that is to say a Yankee eylindeX provi~,ed with ~.nterna7, reinforcing jibs, zs used.
_ 22 Figure 9 shows a graph that is comparable with the graph of figure 8, but in this ease fer the "hand feel"
alread~r mentioned az the beginning.
zn addition, figure 20 again, shows a graph that ~.s comparable with th,e graph of figure 8, but fn this case for Lhe dryness after the press.
The graph of figure ~.1 reproducQa the in~luenca of dx~ring cond~.tiona, such as in particular the r3rying raL~.o Yankee cylinder/drying hood.
The graph o~ figure 12 shows the influenoe o~ the thiaknass~ of the ereping doctor on the thickness of the Z5 tissue p~.per, which here corxesponda to the ppecific volume (bulk). on the other hand, an improved "hand feel" value is also possible ac a constant "bulk"' val~a. 2n the graph, the abbreviation ~GMT'~ stands for the expression "geometric mean ter~eile strength".
Figure Z3 shows a graph which reproduces the in fluanee ef the multilayer production of the tissue paper on the specific volume (bulk) is the case of differez~.t presses, it being possible to nee in particular the advantage re~ul~,ir~g from the use of a shoe press (Tk') as compared with a sueL,ion press roll (SpR).
Kist of deli uationa ~.0 Ta.ssue machine 12 Ti9sue web 14 Flow box 16 Endlcas circulating belt, support~.ng belt 18 Drying cylinder. Yankee cylizlc~er 20 Oppor~ing unit, Whoa press u~,it 22 Press nip, contact nip 24 Re~l,up 26 winding niP
28 ~Indless oiraulating belt, outer wire 30 Stock inlet gap i . 32 Forming element, forming X011, breast roll 34 Evacuated device, suction roll 36 Creping doctor, doctor bar 38 Drying hood 39 Measuring gams ' 40 Carrier drum 42 8poo1 44 Drive 46 Nozzle 4B Slat I
0 Chansze 1 52 Charmel 5a Outlet gap 56 'I'u~bulence generator 58 Croas-maehixle distribution pipe 60 Crvrs-machine distribution pipe 61 cross-machine distribution pipe 62 slice 64 Reel-up 66 Drive 68 Carrier drum ' 70 Reed.
72 Rails i 74 Winda.ng nip 7 6 Tangent 7g k~oint of contact 90 Reel 82 Rails 83 Sensor 84 Contro~.ler 86 3~etuator 88 Pointer 90 Seale 92 8era.sor A 'Distance D Reel d~.ameter F Nip force, force in the Winding rii8 b Thickness ly Nozzle length 1, Slat length ,An.gle of attack, clearance angle ~i 'Rake angle°
Claims (77)
1. A method for production of a web of tissue material, comprising: supplying at least two stock grades to a multilayer flow box; winding up the tissue web on a reel of a reel-up; and maintaining a winding nip having a line pressure of less than or equal to 0.8 kN/m to influence the hardness of the reel produced.
2. The method in accordance with claim 1, wherein the influencing comprises at least one of controlling and regulating the reel hardness.
3. The method in accordance with claim 1, wherein the web is produced in a tissue machine composed of a multilayer flow box, an endless supporting belt, and a drying cylinder and an opposing unit arranged to form a press nip, and the method further includes: guiding the tissue web through the press nip.
4. The method in accordance with claim 3, wherein the reel-up positioned after the press nip.
5. The method in accordance with claim 1, wherein the drying cylinder comprises a Yankee cylinder.
6. The method in accordance with claim 1, wherein the reel-up includes the reel and a carrier drum arranged to form a winding nip.
7. The method in accordance with claim 1, further comprising forming the web on a former having two circulating endless belts, which run together, forming a stock inlet gap, and then over a forming element, such that the inner belt that comes into contact with the forming element.
8. The method in accordance with claim 7, wherein the forming element comprises a forming roll and the inner belt comprises a transport belt.
9. The method in accordance with claim 1, further comprising forming the web on a crescent former having an inner belt formed by a felt.
10. The method in accordance with claim 1, further comprising supporting the tissue web on a supporting belt and guiding the supported web through at least one shoe press.
11. The method in accordance with claim 10, wherein a shoe press unit is assigned to a drying cylinder to form a press nip, and the web is guided through the press nip.
12. The method in accordance with claim 1, further comprising doctoring the tissue web off of the drying cylinder with a creping doctor.
13. The method in accordance with claim 12, wherein the creping doctor is a thin creping doctor.
14. The method in accordance with claim 1, wherein the at least two stock grades comprise at least one of the following stock grades: fibers made of hardwood, in particular short-fiber chemical pulps fibers made of softwood, in particular long-fiber chemical pulps CTMP
(chemical-thermomechanical pulp).
(chemical-thermomechanical pulp).
15. The method in accordance with claim 1, wherein the at least two stock grades comprise a stock grade mixture in which a proportion of fibers made of hardwood lies in a range from about 50% to about 80%.
16. The method in accordance with claim 1, wherein the at least two stock grades comprise a stock grade mixture in which the proportion of fibers made of softwood lies in a range from about 20% to about 50%.
17. The method in accordance with claim 1, wherein the at least two stock grades comprise a stock grade mixture in which a proportion of chemical-thermomechanical pulp (CTMP) lies in a range from 0% to about 20%.
18. The method in accordance with claim 1, further comprising drying the tissue web on a drying cylinder located after a press nip.
19. The method in accordance with claim 18, wherein drying in a relevant wrap region is intensified by a drying hood.
20. The method in accordance with claim 1, wherein the at least two different stock grades comprise short fibers obtained from hardwood, which are used for a layer of the tissue web to face a drying cylinder surface and long fibers obtained from softwood, which are used for a layer on an opposite side of the web.
21. The method in accordance with claim 20, wherein chemical-thermomechanical pulp (CTMP) is additionally used for the layer provided on the opposite side of the web.
22. The method in accordance with claim 21, wherein the layer on the opposite side of the web further includes short fibers.
23. The method in accordance with claim 1, wherein the multilayer flow box comprises a nozzle subdivided into at least two channels by at least one slat extending over an entire machine width.
24. The method in accordance with claim 23, wherein the nozzle is subdivided at least substantially symmetrically into two channels by the slat.
25. The method in accordance with claim 23, wherein the slat extends outward beyond the nozzle in a region of an outlet gap.
26. The method in accordance with claim 1, wherein the multilayer flow box includes at least one of dilution water regulation and section by section control over a machine width.
27. The method in accordance with claim 26, wherein the at least one of dilution water regulation and section by section control over the machine width is provided for the at least two layers.
28. The method in accordance with claim 26, wherein the dilution water regulation and the control is provided at least for a layer of the web arranged to face a forming roll.
29. The method in accordance with claim 1, wherein the web is dried on a drying cylinder under a drying hood, and a proportion of the drying contributed by the drying hood is greater than a proportion of the drying contributed by the drying cylinder.
30. The method in accordance with claim 29, wherein a ratio between the proportion of the drying from the drying hood and the proportion of the drying from the drying cylinder is greater than 55:45.
31. The method in accordance with claim 30, wherein the ratio is greater than or equal to 60:40.
32. The method in accordance with claim 30, wherein the ratio is greater than or equal to 65:35.
33. The method in accordance with claim 30, wherein the ratio is greater than or equal to 70:30.
34. The method in accordance with claim 29, wherein the drying hood is operated at a temperature greater than or equal to 400°C.
35. The method in accordance with claim 34, wherein the drying hood is operated at a temperature greater than or equal to 500°C.
36. The method in accordance with claim 34, wherein the drying hood is operated at a temperature greater than or equal to 600°C.
37. The method in accordance with claim 34, wherein the drying hood is operated at a temperature greater or equal to 700°C.
38. The method in accordance with claim 29, wherein a steam pressure in the drying cylinder is less than or equal to 0.7 MPa.
39. The method in accordance with claim 38, wherein the steam pressure is less than or equal to 0.6 MPa.
40. The method in accordance with claim 38, wherein the steam pressure is less than or equal to 0.5 MPa.
41. The method in accordance with claim 1, wherein at the reel-up, the method includes guiding the tissue web over a carrier drum and winding the web onto a spool.
42. The method in accordance with claim 41, wherein a drive is provided to both the carrier drum and the spool.
43. The method in accordance with claim 41, wherein the carrier drum and spool are arranged to form a winding nip.
44. The method in accordance with claim 43, wherein the line force is less than or equal to 0.5 kN/m.
45. The method in accordance with claim 43, wherein the line force is less than or equal to 0.2 kN/m.
46. The method in accordance with claim 42, wherein a maximum difference between a circumferential speed of the reel and a circumferential speed of the carrier drum is less than 10% of the circumferential speed of the carrier drum.
47. The method in accordance with claim 42, wherein a web tension between a drying cylinder and the carrier drum is set to a predefinable desired value via the drive assigned to the carrier drum, independently of the line force produced in the winding nip.
48. The method in accordance with claim 47, wherein the web tension is at least one of controlled and regulated.
49. The method in accordance with claim 42, wherein the drive assigned to the spool is at least one of controlled and regulated as a function of the speed of the carrier drum.
50. The method in accordance with claim 42, wherein the carrier drum is mounted in a fixed position and the spool is movable.
51. The method in accordance with claim 50, wherein growth in a reel diameter is compensated by appropriate movement of the spool.
52. The method in accordance with claim 42, wherein a winding nip is formed between the carrier roll and a movable spool, and a line force in the winding nip is set via the movable spool.
53. The method in accordance with claim 52, wherein, in order to compensate for growth in diameter of the reel and in order to set the line force in the winding nip, a common control loop is used.
54. The method in accordance with claim 52, further comprising determining the line force in the winding nip via at least one force sensor and regulating the line force by appropriate movement of the spool.
55. The method in accordance with claim 52, wherein, when the line forces in the winding nip are less than or equal to 0.5 kN/m, the movable spool is moved away under control.
56. The method in accordance with claim 52, wherein, when the line forces in the winding nip are less than or equal to 0.2 kN/m, the movable spool is moved away under control.
57. The method in accordance with claim 55, wherein measured variables used for moving the movable spool away under control are reel diameter and the position of the spool or the reel formed on the spool relative to the carrier drum.
58. The method in accordance with claim 57, wherein the position of the reel is measured by sensors.
59. The method in accordance with claim 58, wherein the sensors comprise linear variable differential transformers (LVDT).
60. The method in accordance with claim 52, wherein, to set, control and/or regulate the line force in the winding nip, the method further includes monitoring a region of the winding nip with a CCD camera.
61. The method in accordance with claim 60, wherein a respective distance between the carrier drum and the spool or the reel formed on the spool is registered.
62. The method in accordance with claim 52, wherein the drive assigned to the spool is not changed during the winding operation.
63. The method in accordance with claim 1, wherein a mass per unit area of the tissue web in an uncreped state lies in a range from about 11 g/m2 to about 20 g/m2 and in a creped state lies in a range from about 14 g/m2 to about 24 g/m2 .
64. The method in accordance with claim 1, further comprising forming the web on a crescent former having an inner supporting belt formed by a felt, and guiding the tissue web and felt over at least one evacuated device in a web running direction before a press nip.
65. The method in accordance with claim 64, wherein the evacuated device comprises a suction roll.
66. The method in accordance with claim 64, wherein an outer belt of the crescent former, provided in a region of a forming element, comprises a mesh belt.
67. The method in accordance with claim 1, further comprising pressing the tissue web in a press nip formed between a shoe press having a shoe length in the web running direction greater than or equal to 80 mm.
68. The method in accordance with claim 67, wherein the shoe length is greater than or equal to 120 mm.
69. The method in accordance with claim 67, further comprising producing a line force in the shoe press that lies in the range from about 60 kN/m to about 90 kN/m.
70. The method in accordance with claim 69, wherein a maximum pressing pressure in the press nip is less than or equal to 2 bar.
71. The method in accordance with claim 69, wherein the maximum pressing pressure is less than or equal to 1.5 bar.
72. The method in accordance with claim 67, wherein the shoe press comprises a shoe press unit with a blind-drilled press cover.
73. The method in accordance with claim 1, further comprising drying the web on a drying cylinder with reinforcing ribs in the interior.
74. The method in accordance with claim 73, wherein the drying cylinder comprises a Yankee cylinder.
75. The method in accordance with claim 73, wherein the web is creped from the drying cylinder by a creping doctor having a thickness of less than or equal to 0.9 mm.
76. The method in accordance with claim 75, wherein an angle of attack between a tangent to the drying cylinder and the creping doctor is less than or equal to 20°.
77. The method in accordance with claim 75, wherein a rake angle of the creping doctor is greater than or equal to 15°.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA2713601A CA2713601C (en) | 2002-04-25 | 2003-03-20 | Method for the production of a web of tissue material |
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE2002118509 DE10218509A1 (en) | 2002-04-25 | 2002-04-25 | Process for making a tissue web |
| DE10218509.3 | 2002-04-25 | ||
| PCT/EP2003/050074 WO2003091499A1 (en) | 2002-04-25 | 2003-03-20 | Method for production of a tissue web |
Related Child Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA2713601A Division CA2713601C (en) | 2002-04-25 | 2003-03-20 | Method for the production of a web of tissue material |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2483818A1 CA2483818A1 (en) | 2003-11-06 |
| CA2483818C true CA2483818C (en) | 2010-11-23 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA2483818A Expired - Lifetime CA2483818C (en) | 2002-04-25 | 2003-03-20 | Method for the production of a web of tissue material |
| CA2713601A Expired - Fee Related CA2713601C (en) | 2002-04-25 | 2003-03-20 | Method for the production of a web of tissue material |
Family Applications After (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA2713601A Expired - Fee Related CA2713601C (en) | 2002-04-25 | 2003-03-20 | Method for the production of a web of tissue material |
Country Status (7)
| Country | Link |
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| EP (2) | EP1501981B1 (en) |
| JP (2) | JP4338081B2 (en) |
| AU (1) | AU2003219169A1 (en) |
| BR (1) | BRPI0308838B1 (en) |
| CA (2) | CA2483818C (en) |
| DE (1) | DE10218509A1 (en) |
| WO (1) | WO2003091499A1 (en) |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE10326304A1 (en) * | 2003-06-11 | 2005-02-03 | Voith Fabrics Patent Gmbh | Method and device for producing a tissue web |
| FI117171B (en) | 2004-04-07 | 2006-07-14 | Metso Paper Inc | Rolling control method and apparatus |
| SE529130C2 (en) * | 2004-05-26 | 2007-05-08 | Metso Paper Karlstad Ab | Paper machine for manufacturing fiber web of paper, comprises clothing that exhibits three-dimensional structure for structuring fiber web |
| DE102006062237A1 (en) * | 2006-12-22 | 2008-06-26 | Voith Patent Gmbh | Machine for producing a fibrous web |
| JP5184920B2 (en) * | 2008-03-04 | 2013-04-17 | キヤノン株式会社 | Broadcast receiving apparatus, control method thereof, management apparatus, and control method thereof |
| DE102012110790B4 (en) * | 2012-11-09 | 2017-04-27 | Windmöller & Hölscher Kg | Method for determining the winding quality of a film roll |
| SE1651680A1 (en) * | 2016-12-19 | 2018-04-24 | Valmet Oy | A method for making tissue paper |
| EP3737792B1 (en) * | 2018-01-11 | 2024-07-31 | A.Celli Paper S.P.A. | Machine and method for manufacturing tissue paper |
| SE542214C2 (en) * | 2018-10-12 | 2020-03-10 | Valmet Oy | A tissue paper making machine and a method of operating a tissue paper making machine |
| DE102019120122A1 (en) | 2019-07-25 | 2021-01-28 | Saint-Gobain Isover G+H Ag | Method for winding up a material web, in particular made of a compressible, compressible material and device for carrying out the method |
Family Cites Families (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA2098327A1 (en) * | 1993-03-02 | 1994-09-03 | Steven Lawrence Edwards | Method for making soft layered tissues |
| JPH0841793A (en) * | 1994-07-29 | 1996-02-13 | Ishikawajima Harima Heavy Ind Co Ltd | Controller for orienting property of wire cloth part in paper machine |
| US5487813A (en) * | 1994-12-02 | 1996-01-30 | The Procter & Gamble Company | Strong and soft creped tissue paper and process for making the same by use of biodegradable crepe facilitating compositions |
| US6332952B1 (en) * | 1996-04-26 | 2001-12-25 | Kimberly-Clark Worldwide, Inc. | Tissue with strikethrough resistance |
| DE19745005A1 (en) * | 1997-01-25 | 1998-07-30 | Voith Sulzer Papiertech Patent | Winding machine for continuously winding up a material web on spool, especially paper or cardboard |
| US5944273A (en) * | 1997-07-03 | 1999-08-31 | Kimberly-Clark Worldwide, Inc. | Parent roll for tissue paper |
| DE19756422A1 (en) * | 1997-12-18 | 1999-06-24 | Voith Sulzer Papiertech Patent | Machine for producing a fibrous web, in particular a tissue paper web |
| FI110622B (en) * | 1998-04-30 | 2003-02-28 | Metso Paper Inc | A method and apparatus for improving the drying capacity of a blanket of a Yankee cylinder |
| US6036137A (en) * | 1998-12-17 | 2000-03-14 | Valmet-Karlstad Ab | Apparatus and method for winding paper |
| JP3640592B2 (en) * | 2000-03-31 | 2005-04-20 | ユニ・チャーム株式会社 | Multi-layered water-decomposable fiber sheet |
| US6432267B1 (en) * | 1999-12-16 | 2002-08-13 | Georgia-Pacific Corporation | Wet crepe, impingement-air dry process for making absorbent sheet |
| DE10030199A1 (en) * | 2000-06-20 | 2002-01-03 | Voith Paper Patent Gmbh | Method and winding machine for the continuous winding of a material web |
| US6365000B1 (en) * | 2000-12-01 | 2002-04-02 | Fort James Corporation | Soft bulky multi-ply product and method of making the same |
-
2002
- 2002-04-25 DE DE2002118509 patent/DE10218509A1/en not_active Withdrawn
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2003
- 2003-03-20 BR BRPI0308838A patent/BRPI0308838B1/en active IP Right Grant
- 2003-03-20 AU AU2003219169A patent/AU2003219169A1/en not_active Abandoned
- 2003-03-20 CA CA2483818A patent/CA2483818C/en not_active Expired - Lifetime
- 2003-03-20 JP JP2003588016A patent/JP4338081B2/en not_active Expired - Fee Related
- 2003-03-20 EP EP03714965A patent/EP1501981B1/en not_active Expired - Lifetime
- 2003-03-20 WO PCT/EP2003/050074 patent/WO2003091499A1/en active Application Filing
- 2003-03-20 CA CA2713601A patent/CA2713601C/en not_active Expired - Fee Related
- 2003-03-20 EP EP12165116A patent/EP2481849A1/en not_active Withdrawn
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2009
- 2009-04-13 JP JP2009097186A patent/JP2009185442A/en active Pending
Also Published As
| Publication number | Publication date |
|---|---|
| JP2005521808A (en) | 2005-07-21 |
| EP1501981B1 (en) | 2013-02-27 |
| AU2003219169A1 (en) | 2003-11-10 |
| BR0308838A (en) | 2005-03-22 |
| CA2483818A1 (en) | 2003-11-06 |
| DE10218509A1 (en) | 2003-11-06 |
| JP2009185442A (en) | 2009-08-20 |
| WO2003091499A1 (en) | 2003-11-06 |
| BRPI0308838B1 (en) | 2016-03-15 |
| CA2713601A1 (en) | 2003-11-06 |
| CA2713601C (en) | 2013-08-06 |
| EP2481849A1 (en) | 2012-08-01 |
| JP4338081B2 (en) | 2009-09-30 |
| EP1501981A1 (en) | 2005-02-02 |
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| EEER | Examination request | ||
| MKEX | Expiry |
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