EP0870865A2 - Patin de pressage - Google Patents

Patin de pressage Download PDF

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Publication number
EP0870865A2
EP0870865A2 EP98101781A EP98101781A EP0870865A2 EP 0870865 A2 EP0870865 A2 EP 0870865A2 EP 98101781 A EP98101781 A EP 98101781A EP 98101781 A EP98101781 A EP 98101781A EP 0870865 A2 EP0870865 A2 EP 0870865A2
Authority
EP
European Patent Office
Prior art keywords
piston
cylinder
pressure
subunits
shoe
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
EP98101781A
Other languages
German (de)
English (en)
Other versions
EP0870865A3 (fr
Inventor
Christian Schiel
Joachim Dr. Grabscheid
Wolfgang Schuwerk
Rudolf Hasenfuss
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Voith Patent GmbH
Original Assignee
Voith Sulzer Papiermaschinen GmbH
Voith Sulzer Papiertechnik Patent GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Voith Sulzer Papiermaschinen GmbH, Voith Sulzer Papiertechnik Patent GmbH filed Critical Voith Sulzer Papiermaschinen GmbH
Publication of EP0870865A2 publication Critical patent/EP0870865A2/fr
Publication of EP0870865A3 publication Critical patent/EP0870865A3/fr
Pending legal-status Critical Current

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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
    • D21F3/0209—Wet presses with extended press nip
    • D21F3/0218—Shoe presses

Definitions

  • the invention relates to a shoe press unit of a paper or Cardboard machine for the treatment of a fibrous web in one with a counter surface, in the direction of web travel extended press zone, with at least one press shoe, one flexible press belt guided over the press shoe and at least one supported on a carrier by a cylinder / piston unit formed force element through which the Press band can be pressed against the counter surface.
  • shoe press units of this type Presetting the setting pressure distribution unchangeable or to provide an adjustability of this pressure curve in such a way that the progression of the Pressing pressure is changeable over the length of the press zone.
  • the adjustability was either geometric by, for example, gradually moving the press shoe relative to the resultant of the contact pressure or by pressing the shoe by means of two rows of pressure cylinders achieved that can be acted upon with different pressure were, or by introducing a torque in a way that does not change the line force is (DE 196 31 638.3).
  • a gradual displacement of the shoe relative to the level of the resulting contact pressure brings among other things the disadvantage with the fact that the stages are too large due to the design and the machine for moving the shoe can be switched off must what a corresponding loss of production with it brings.
  • the aim of the invention is to provide an improved shoe press unit to create the type mentioned at the reduced Effort and correspondingly higher reliability optional allows an additional influence on the pressure profile, without accepting the disadvantages mentioned above Need to become.
  • the object is achieved according to the invention in that Pressure chamber of the cylinder / piston unit at least one Force element at least a pair of cylinder / piston subunits is provided, one behind the other in the web running direction arranged and so over separate pressure fluid lines can be acted upon by a tilting moment of the press shoe convey a respective tilt axis, which is at least in extends substantially perpendicular to the web running direction.
  • the cylinder / piston sub-units are used to achieve a particularly compact design preferably in the respective Integrated power element. At best, this is a minimal one Adapt the existing components.
  • cylinder / piston subunits are each one Row preferably via a common pressure fluid line actable.
  • the two subunits are advantageously one the respective pair of cylinder / piston subunits Fluid pressures controlled or regulated so that the Sum of the two fluid pressures is constant. This ensures that the line force with the same large piston areas not changed in both lines when tilted modified the pressure distribution curve in the press zone becomes.
  • Shoe press unit is through the cylinder / piston sub-units only a fraction of the total Contact pressure applied. Even greater control inaccuracies have practically no influence on the respective Business. This is especially true in the event that the hydraulic Support the shoe press unit and one with it cooperating counter roll from a common Pressure source to be fed, especially for damage the roller bearing of the one working with the shoe press unit, also hydraulically supported counter roll due to of deviations of the actual pressures from the target pressures avoid. To achieve a respective tilt, if necessary the two rows of cylinder / piston subunits to apply different pressures, what in practice about appropriate pressure control he follows. Will now through the cylinder / piston subunits only a fraction of the total pressure applied, So it is practically impossible that any occurring Control inaccuracies for larger, the roller bearings lead stressful forces.
  • the cylinder / piston subunits expediently at most about 25% and preferably about 7.5% to about 15% of the total contact pressure applied.
  • the two subunits of a respective pair of fluid pressures acting on cylinder / piston subunits are controlled or regulated so that the ratio between the one acting on the pressure chamber of the force element Fluid pressure and the sum of the two subunits Fluid pressures is constant.
  • the control respectively Control of the fluid pressures of the cylinder / piston subunits can in particular also take place in such a way that the sum of the contact forces of the cylinder / piston subunits changes analogously with the line force. This too Precautions prevent a disadvantageously high load on the bearing a hydraulically supported counter roller.
  • the shoe press unit is at least one piston Cylinder / piston subunit on the one hand in a carrier side Blind hole and on the other hand in one aligned with this Cylinder bore in the pressure piston of the force element can be tilted and used sealing.
  • the piston of a respective cylinder / piston subunit provided with a continuous flow channel be, via which the carrier-side can be acted upon with pressure fluid Blind bore with the section of the cylinder bore on the press shoe side is connected in the pressure piston.
  • the blind bore on the carrier side and the cylinder bore in the pressure piston can expediently have the same size Own diameter.
  • the piston of the relevant cylinder / piston subunit then hovers as a connection free of axial forces between the carrier and the pressure piston.
  • the axial stroke of the piston of a respective cylinder / piston subunit can preferably be provided on the carrier side Be limited.
  • the stroke to a few mm is conceivable.
  • the pressure fluid supply for the cylinder / piston subunits and / or the or the force elements is expediently carried out over a direction extending transversely to the web running direction carrier-side provided with separate pressurized fluid channels Distribution strip.
  • This distribution strip can be in one formed in the carrier, extending transversely to the web running direction Recess be used, in this case preferably at least part of the pressure fluid channels between the bar and the inner circumference of the recess can be.
  • a particularly advantageous practical embodiment of the The shoe press unit according to the invention is characterized in that that the two subunits of a respective pair of cylinder / piston subunits and if necessary the two Rows of cylinder / piston subunits through a common one Pressurized fluid source are supplied, with a cylinder / piston subunit of a respective pair or one Row of subunits above one pressure regulator and the other Subunit of the respective pair or the other row from subunits through a flow restrictor to the common one Pressurized fluid source are connected, and that the cylinder / piston subunits to a common addition valve are connected to the sum of the two subunits of a respective pair or the two rows of subunits pressurizing fluid pressures when tipping under constant line force to keep constant, each one desired tilting moment is adjustable via the pressure regulator.
  • the addition valve is preferably one with a Flow regulation provided pressure fluid line connected to the pressure chamber of the force element (s) and so interpreted that the relationship between the each Pressure space of the fluid pressure acting on the force elements and the sum of the two subunits of each Pair or the two rows of subunits acting fluid pressures is kept constant.
  • the flow rate regulation can, for example, be one Flow controller, a fixed throttle and / or a throttle include, the setting of which is in the press zone generated line force changes.
  • the pressure chamber of the force element is preferably one separate pressure fluid source supplied.
  • the shoe press unit can be used, for example, as a shoe press roll formed with a press jacket forming the flexible press belt be.
  • Figure 1 shows in a purely schematic, partially sectioned Side view provided in the form of a shoe press roll
  • Shoe press unit 10 with associated pressurized fluid supply and assigned tilt control. That of a paper or board machine assigned shoe press unit 10 is used for treatment a fibrous web in a formed with a counter surface 12, Press zone 14 extended in the direction of web travel L it comprises at least one press shoe 16, one over the Press shoe 16 guided, provided as a flexible press belt flexible press jacket 18 and at least one on a carrier 20th supported, formed by a cylinder / piston unit Force element 22 through which the flexible press jacket 18 against that formed in the present case by a counter roller 24 Counter surface 12 can be pressed.
  • At least one in the pressure chamber 26 of the cylinder / piston unit Force element 22 is at least a pair of cylinder / piston subunits 28, 30 provided in the web running direction L arranged one behind the other and via separate pressure fluid lines 32, 34 can be acted on so that they are the press shoe 16 convey a tilting moment about a respective tilting axis, which at least substantially perpendicular to the direction of web travel L extends.
  • the cylinder / piston sub-units 28, 30 are in the respective Force element 22 integrated.
  • each comprises Force element 22 a pressure piston 36, which is in a cylinder 38 is stored.
  • the press shoe 16 is thus via one or more pressure pistons 36, the one in one, respectively several preferably hydraulic cylinders 38 or beds are stored, pressed.
  • the majority of the resulting contact pressure is generated by the oil pressure in the pressure chamber 26 of the force element 22. This pressure is built up by a pump P 1 . It can be read on a PI 1 display.
  • the pump P 1 sucks the oil from an oil tank 40.
  • the control valves and the oil return lines etc. are omitted in the assigned hydraulic circuit.
  • a hydraulic pump P 2 which draws oil from an oil reservoir 42 and requests it into a pressure line 44, serves to generate the appropriate pressure.
  • the cylinder / piston subunit 30 is operated via a pressure regulator 48 supplied with adjustable pressure.
  • the corresponding pressure can be read on a display PI 2 and can be set from a value of zero to a maximum value which is less than or equal to the system pressure in the pressure line 44.
  • connecting line 52 Via one between the pressure chamber 26 and the addition valve 50 provided connecting line 52 is from the pressure chamber 26 a reference pressure is removed.
  • this connecting line 52 can be a flow rate regulation, for example in Form an adjustable throttle 54 to be built in to vibrate of the addition valve 50 to prevent.
  • a flow restrictor 58 is installed between the pressure line 44 and the pressure fluid line 32 leading to the cylinder / piston subunit 28, which ensures that the pressure in the pressure line 44 does not drop too much when 30 pressures are set in the cylinder / piston subunits that are significantly higher than the mean pressure p 3rd + p 2nd 2nd are.
  • the flow limiter 58 can be, for example, a throttle or a flow regulator, the regulated flow rate of which is smaller than the flow rate of the pump P 2 . This ensures that even at a pressure "zero" in the pressure fluid line 32 leading to the cylinder / piston subunit 28, the maximum system pressure in the pressure line 44 is maintained.
  • the desired tilt of the press shoe 16 and thus the Pressure distribution curve in the press zone 14 is carried out by a Regulation of the pressure in the cylinder / piston subunit leading pressure fluid line 34 by means of Pressure regulator 48.
  • the shoe press unit is the pressure piston pressed against the pressure shoe 16 vertically displaceable in a cylinder block 62 and tiltably guided in an elastic seal 64.
  • the cylinder / piston sub-units 28, 30 comprise in the illustrated Embodiment each have a cylinder bore 66 and 68 in the pressure piston 36 and one provided in the carrier 20 Blind hole 70 or 72.
  • Bores 82 and 84 or 86 and 88 ensure that oil through the pistons 74 and 76 can flow through.
  • the pistons 74, 76 can be moved vertically with elastic sealing rings 90 or 92 and tiltable in the cylinder and blind bores 66 and 70 or 68 and 72 led.
  • the cylinder bores 66 and 68 penetrate the pistons 74, 76 completely so that the hydraulic pressure of the cylinder / piston subunits 28, 30 directly onto the press shoe 16 works.
  • Axial seals 94, 96 seal the cylinder bores 66, 68 on the shoe side. For easier assembly of these axial seals 94, 96 each serve a pressed-in retaining ring 98 or 100.
  • each a cylinder / piston unit Comprehensive force elements 22 are connected to one another Oil supply channel 102 and bores 104 are supplied with pressurized oil. The supply of those serving to generate a tipping moment Cylinder / piston subunits 28, 30 take place via connecting channels 106 or 108 and bores 110 or 112.
  • the channels 102, 106 and 108 are just like the bores 104 provided in a distributor strip 114, which is in a groove or recess 116 is embedded in the carrier 20.
  • the distribution bar 114 is screwed to the carrier 20.
  • Elastic Seals 118 seal the different pressure chambers against each other from.
  • Figure 3 shows the pressure piston 36 of a shoe press unit in schematic top view.
  • this schematic top view are the cylinder bores 66 and 68 and the front or Axial seals 94 and 96 can be seen.
  • Figure 4 shows a schematic, partially sectioned side view an embodiment of the intended for tilt control Addition valve 50.
  • This includes a valve block 122 and a cover 124, which with the valve block 122 by means Screws not screwed axially in the cutting plane is.
  • a stepped piston 126 is arranged in the valve block 122, which comprises three sections of different diameters D 1 , D 2 and D 3 , which are fitted in cylinder bores 128, 130 and 132 in a sealing manner but vertically movable.
  • An annular space 134 surrounding the middle piston section with the diameter D 2 is connected via holes 136, 138 and 140 to an unpressurized return oil space 142.
  • a screw 144 closes the bore 138 downwards.
  • the annular piston area A 2 formed between the piston portion of diameter D 2 and the piston portion having the diameter D 3 is equal to that on the lower end side of the diameter D 3 having the piston section provided rotary piston area A third
  • the diameter D 1 can be selected as desired.
  • the top formed by the piston portion of diameter D 1 circular piston area A 1 to the pressure p 1 of the pressure chamber 26 (see also Figure 1), the annular piston area A 2 which the cylinder / piston subunit 30 applied pressure p 2 and the circular piston area A 3 the cylinder / piston subunit p 26 applied pressure 3 exposed.
  • the diameter D 1 within the technically manageable pressure levels for the cylinder / piston subunits 28, 30 becomes so large choose as possible.
  • the pressure p 2 acting on the cylinder / piston subunit 30 is predetermined via the pressure regulator 48 (see FIG. 1, for example) formed by a pressure regulator valve.
  • Figure 5 shows a schematic, partially sectioned side view another embodiment 50 'of such an additive valve.
  • valve 50 ' in turn comprises a valve block 122' and a cover 124 'which can be screwed thereto.
  • valve block 122 ' there is again a stepped piston 126' with the diameters D 1 , D 2 and D 3 .
  • the stepped piston 126 ' is provided with guide pins 146, 148, which in a bore 150 in the cover 124 'or a bore 152 in the valve block 122 'vertically displaceable are stored.
  • the stepped piston 126 ' is provided with sealing rings 154 and 156, each in a cylindrical bore 158 or 160 of the valve block 122 'run.
  • the holes 150 and 152 are each through a Screw 162 or 164 closed.
  • the pressure p 2 is preselected again via the pressure regulator 48 (see FIG. 1).
  • ring piston area A 2 is formed between the piston portion of diameter D 1 and the piston portion with the diameter D. 2
  • the space delimited by the bore 152 between the guide pin 148 and the screw 164 is kept depressurized.
  • Figure 6 is a practical embodiment for three different tilt settings a, b and c in the pressure profile in the web running direction an aging factor of the intended felting of 1.0.
  • the path along the is on the abscissa Web running direction in mm and on the coordinate the pressure in MPa applied.
  • FIG. 7 shows the corresponding pressure profiles for a comparable one practical embodiment with an aging factor the intended felting of 0.3.
  • the aging factor shows how much the compressibility of the felt has decreased compared to the new condition.

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  • Paper (AREA)
EP98101781A 1997-04-10 1998-02-03 Patin de pressage Pending EP0870865A3 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19714939A DE19714939A1 (de) 1997-04-10 1997-04-10 Schuhpreßeinheit
DE19714939 1997-04-10

Publications (2)

Publication Number Publication Date
EP0870865A2 true EP0870865A2 (fr) 1998-10-14
EP0870865A3 EP0870865A3 (fr) 1999-02-10

Family

ID=7826099

Family Applications (1)

Application Number Title Priority Date Filing Date
EP98101781A Pending EP0870865A3 (fr) 1997-04-10 1998-02-03 Patin de pressage

Country Status (4)

Country Link
US (1) US6036820A (fr)
EP (1) EP0870865A3 (fr)
JP (1) JPH10292285A (fr)
DE (1) DE19714939A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0896088A2 (fr) * 1997-08-08 1999-02-10 Beloit Technologies, Inc. Réglage du profil dans le sens de la machine du patin d'une presse à zone de pressage prolongée

Families Citing this family (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10028102A1 (de) * 2000-06-07 2001-12-13 Voith Paper Patent Gmbh Schuhpreßeinheit
US6610173B1 (en) 2000-11-03 2003-08-26 Kimberly-Clark Worldwide, Inc. Three-dimensional tissue and methods for making the same
US6752907B2 (en) * 2001-01-12 2004-06-22 Georgia-Pacific Corporation Wet crepe throughdry process for making absorbent sheet and novel fibrous product
DE10133531A1 (de) * 2001-07-11 2003-01-30 Kuesters Eduard Maschf Langspalt-Walzenpresse zum Entwässern einer Faserstoffbahn
DE10260202A1 (de) * 2002-06-25 2004-01-22 Voith Paper Patent Gmbh Vorrichtung zur Beeinflussung und/oder Überwachung eines Druckprofils
CN100348799C (zh) * 2002-08-30 2007-11-14 埃杜阿德库斯特斯机器厂两合公司 用于使纤维织物脱水的长辊隙辊压机
US8293072B2 (en) 2009-01-28 2012-10-23 Georgia-Pacific Consumer Products Lp Belt-creped, variable local basis weight absorbent sheet prepared with perforated polymeric belt
US20070062656A1 (en) * 2005-09-20 2007-03-22 Fort James Corporation Linerboard With Enhanced CD Strength For Making Boxboard
US8540846B2 (en) 2009-01-28 2013-09-24 Georgia-Pacific Consumer Products Lp Belt-creped, variable local basis weight multi-ply sheet with cellulose microfiber prepared with perforated polymeric belt
US8361278B2 (en) 2008-09-16 2013-01-29 Dixie Consumer Products Llc Food wrap base sheet with regenerated cellulose microfiber
US9309627B2 (en) 2011-07-28 2016-04-12 Georgia-Pacific Consumer Products Lp High softness, high durability bath tissues with temporary wet strength
SE538098C2 (sv) 2013-11-14 2016-03-01 Valmet Aktiebolag En långnypsvals med ett stödelement för behandling av en fiberbana

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3336462A1 (de) * 1982-10-14 1984-04-19 Valmet Oy, 00130 Helsinki Vorrichtung mit langer presszone zur pressbehandlung einer faserstoffbahn
US5167768A (en) * 1991-11-07 1992-12-01 Beloit Corporation Wide nip web press and method using a press shoe with two pivots
DE4425915A1 (de) * 1994-07-21 1996-02-01 Voith Sulzer Papiermasch Gmbh Langspalt-Presse
US5650048A (en) * 1996-01-31 1997-07-22 Beloit Technologies, Inc. Extended nip press with hydraulic pressure equalizer valve

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19631638A1 (de) * 1996-08-05 1998-02-12 Voith Sulzer Papiermasch Gmbh Pressenanordnung

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3336462A1 (de) * 1982-10-14 1984-04-19 Valmet Oy, 00130 Helsinki Vorrichtung mit langer presszone zur pressbehandlung einer faserstoffbahn
US5167768A (en) * 1991-11-07 1992-12-01 Beloit Corporation Wide nip web press and method using a press shoe with two pivots
DE4425915A1 (de) * 1994-07-21 1996-02-01 Voith Sulzer Papiermasch Gmbh Langspalt-Presse
US5650048A (en) * 1996-01-31 1997-07-22 Beloit Technologies, Inc. Extended nip press with hydraulic pressure equalizer valve

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0896088A2 (fr) * 1997-08-08 1999-02-10 Beloit Technologies, Inc. Réglage du profil dans le sens de la machine du patin d'une presse à zone de pressage prolongée
EP0896088A3 (fr) * 1997-08-08 1999-08-04 Beloit Technologies, Inc. Réglage du profil dans le sens de la machine du patin d'une presse à zone de pressage prolongée

Also Published As

Publication number Publication date
JPH10292285A (ja) 1998-11-04
EP0870865A3 (fr) 1999-02-10
DE19714939A1 (de) 1998-10-15
US6036820A (en) 2000-03-14

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