US3733711A - Apparatus for and method of treating a web - Google Patents

Apparatus for and method of treating a web Download PDF

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Publication number
US3733711A
US3733711A US00178361A US3733711DA US3733711A US 3733711 A US3733711 A US 3733711A US 00178361 A US00178361 A US 00178361A US 3733711D A US3733711D A US 3733711DA US 3733711 A US3733711 A US 3733711A
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United States
Prior art keywords
web
cylinder
air pressure
suction
immediately adjacent
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Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
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US00178361A
Inventor
J Haythornthwaite
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Scapa Blackburn Ltd
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Scapa Dryers Ltd
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Publication of US3733711A publication Critical patent/US3733711A/en
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F26—DRYING
    • F26B—DRYING SOLID MATERIALS OR OBJECTS BY REMOVING LIQUID THEREFROM
    • F26B13/00—Machines and apparatus for drying fabrics, fibres, yarns, or other materials in long lengths, with progressive movement
    • F26B13/24—Arrangements of devices using drying processes not involving heating
    • F26B13/28—Arrangements of devices using drying processes not involving heating for applying pressure; for brushing; for wiping
    • 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
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F26—DRYING
    • F26B—DRYING SOLID MATERIALS OR OBJECTS BY REMOVING LIQUID THEREFROM
    • F26B13/00—Machines and apparatus for drying fabrics, fibres, yarns, or other materials in long lengths, with progressive movement
    • F26B13/10—Arrangements for feeding, heating or supporting materials; Controlling movement, tension or position of materials
    • F26B13/14—Rollers, drums, cylinders; Arrangement of drives, supports, bearings, cleaning
    • F26B13/18—Rollers, drums, cylinders; Arrangement of drives, supports, bearings, cleaning heated or cooled, e.g. from inside, the material being dried on the outside surface by conduction

Abstract

A web is treated, for example dried, by passing it around a rotary cylinder, and deflecting it by air pressure, positive and/or suction, applied to the web immediately adjacent the junction of the web and the cylinder to cause the web to contact a greater portion of the circumferential surface of the cylinder than it would in the absence of the air pressure.

Description

United States Patent [191 Haythornthwaite [451 May 22, 1973 [22] Filed:
[54] APPARATUS FOR AND METHOD OF TREATING A WEB [75] Inventor: James Haythornthwnite,
Quebec, Canada [73] Assignee: Scapa Dryers (Canada) Ltd.,
Joliette, Quebec, Canada Sept. 7, 1971 [21] Appl. No.: 178,361
Joliette,
[52] U.S. Cl. ..34/23, 34/114, 34/155, 226/95 [51] Int. Cl. ..B65b 17/28, F26b 13/08 [58] Field of Search ..34/23, 114, 155, 34/160; 226/95 [5 6] References Cited UNITED STATES PATENTS 1/1972 Rodwin ..34/114 2,777,213 1/1957 Dungler ..34/160 3,316,657 5/1967 Haywood ..34/160 X 3,384,973 5/1968 Johansson ..34/23 3,406,464 10/1968 Clark ..34/155 X Primary Examiner-William F. ODea Assistant ExaminerPeter D. Ferguson Attorney-Spencer & Kaye [57] ABSTRACT A web is treated, for example dried, by passing it around a rotary cylinder, and deflecting it by air pressure, positive and/or suction, applied to the Web immediately adjacent the junction of the web and the cylinder to cause the web to contact a greater portion of the circumferential surface of the cylinder than it would in the absence of the air pressure.
4 Claims, 8 Drawing Figures PAIENTEDmmze I975 SHEET 1 BF 4 FIG. I.
FIGS.
FIGZ.
PAIENTEDMAY22|975 3 733 711 SHEET 2 OF 4 FIG. 4.
FIG. 5.
PATENTEUHAY 22 I975 SHEET 3 BF 4 FIG. 7.
PATENTEDHAYEZ 0975 3. 733, 711
SHEET l UF 4 APPARATUS FOR AND METHOD OF TREATING A WEB This invention relates to apparatus for and a method of treating a web by passing a web around one or more rotary cylinders.
In papermaking for example, the paper web is passed around one or more rotary cylinders for drying purposes. Usually a drying felt is also passed around the drying cylinder, with the paper web between the felt and the cylinder, to press the web against the cylinder to obtain close contact between the cylinder and the web.
According to this invention, the web is deflected by air pressure applied immediately adjacent the junction of the web and a cylinder, so as to cause the web to contact a greater portion of the circumferential surface of the cylinder than would be the case if the air pressure was not applied. The increased contact between the cylinder and the web enables the treatment, for example the drying, to be carried out more effectively. In paper drying, the increase in drying efficiency may in fact be such that the dryer felt can be omitted.
The air pressure may be applied to the web as it approaches the cylinder and/or as it leaves the cylinder.
The air pressure may be negative, i.e., suction, applied in the throat between the web and the cylinder. The suction may be produced by an apropriately shaped foil suitably positioned in the throat, the suction being produced by the air flow around the foil caused by the motion of the web and the cylinder. Alternatively, the suction may be produced by a suction bar positioned in the throat, with suction being applied to the interior of the suction bar from an external source,
'and the suction bar having aperture means directed to wards the web so that the web is sucked against the cylinder.
Alternatively or additionally, the air pressure may be positive and applied to the web on the oppposite side thereof to the cylinder. In this case, the pressure may be produced by a foil positioned immediately adjacent the junction of the web and the cylinder on the opposite side of the web to the cylinder, the air pressure being produced by the air flow around the foil caused by the motion of the web. Alternatively, the air pressure may be produced by a pressure bar positioned immediately adjacent the junction of the web and the cylinder on the opposite side of the web to the cylinder, the air pressure being supplied to the interior of the pressure bar from an external source, and the pressure bar having aperture means directed towards the web so that the web is forced by the air pressure into contact with the cylinder.
Both positive air pressure and suction may be applied to the web. In this case, the air sucked into the suction bar may subsequently be ejected from the pressure bar. The air may be heated before it is ejected from the pressure bar to increase the drying efficiency.
The rate of air sucked or blown may be adjustable to vary the tension in the web and obtain optimum conditions. In particular, the rate of air sucked or blown may be separately adjustable at different positions along the width of the web to cater for varying conditions across the web.
Embodiments of the invention will now be described, by way of example, with reference to the accompanying diagrammatic drawings, of which:
FIG. 1 is a side view of paper drying apparatus using suction,
FIGS. 2 and 3 are side views of part of the apparatus of FIG. 1 showing different suction producing means,
FIG. 4 is a side view of paper drying apparatus using positive air pressure,
FIGS. 5 and 6 are side views of part of the apparatus of FIG. 4 showing different positive air pressure producing means,
FIG. 7 is a side view of paper drying apparatus using suction and positive air pressure, and
FIG. 8 is a perspective view of paper drying apparatus using suction and air pressure.
Referring first to FIG. 1', the drying section of papermaking apparatus includes a series of rotary drying cylinders 1 to 5 over which the paper web 6 successively passes. No drying felt is used. Immediately adjacent each junction of the web 6 and cylinder (except the first and last junctions), suction indicated by arrows S is applied between the web 6 and the cylinder to deflect the web into greater contact with the cylinder. The straight path which the web 6 would follow in the absence of the suction is shown in dotted lines. It will be seen that the application of suction causes the web 6 to engage a greater proportion of the circumferential surface of each cylinder than would otherwise be the case. The amount of suction required for optimum performance in any particular set of circumstances can readily be ascertained by routine trial and experiment.
FIG. 2 shows how the suction can be obtained by appropriately shaped stationary foils 7 positioned between the web 6 and cylinders, immediately adjacent the junctions thereof, and extending across the width of the web. The suction is caused by air flow around the foils 7 which results from the motion of the cylinders and the web 6.
FIG. 3 shows how the suction can be obtained by suction bars 8 positioned between the web 6 and the cylinders, immediately adjacent the junctions thereof, and extending across the width of the web with aperture means directed towards the web 6. The suction bars 8 are connected to an external source of suction (not shown) which applies suction to the interior of the suction bars 8.
FIG. 4 is similar to FIG. 1, but shows the application of positive air pressure, indicated by arrows P, instead of suction, the positive air pressure being applied to the web immediately adjacent its junctions with the cylinders on the opposite side of the web 6 to the cylinders. FIG. 5 shows the positive air pressure obtained by foils 9 positioned immediately adjacent the junctions of the web 6 and the cylinders, on the opposite side of the web 6 to the cylinders. The positive air pressure is produced by the flow of air around the foils 9 caused by the movement of the web 6. FIG. 6 shows the positive air pressure being obtained by pressure bars 10 which are similar to the suction bars 8, except that they are on the opposite side of the web, and positive air pressure is applied to them.
FIG. 7 is similar to FIGS. 1 and 4, but shows the use of suction and positive air pressure, the suction being applied as the web 6 contacts a cylinder, and the positive air pressure being applied as the web 6 leaves a cylinder. Such an arrangement is shown in more detail in FIG. 8. The two suction bars 8 shown are connected by ducting 11 to the intake of an air blower 12, whose outlet is connected by ducting 13 to the two pressure bars shown via a heat exchanger 14 and a damper controller 15.
Thus, air sucked into the suction bars 8 is subsequently ejected from the pressure bars 10, after first being heated in heat exchanger 14. Hot fluid from any convenient source flows through the heat exchanger 14 through lines 16. The damper controller 15 is adjustable to vary the rate of air flow in the system. if desired, the suction bars 8 and pressure bars 10 may be equipped with adjustable slides to vary the size of the apertures therein differently from place to place across the width of the web 6.
It is also possible to apply suction and positive air pressure immediately adjacent to the samejunction, for example by a suction bar 8 on one side of the web and a pressure bar 10 on the opposite side of the web 6.
Since no drying felt is necessary, all the usual accessories needed for driving the felt are not required. Also, no pockets are produced between the web and a felt, and consequently pocket ventilators are not required. Thus, the drying apparatus is simplified and reduced in cost, and the drying of the web is improved both at different stages in the apparatus and also across the width of the web at any stage.
I claim: s
1. A method of treating a web including passing the web around a rotary cylinder, and deflecting the web by air pressure applied to the web immediately adjacent the junction of the web and the cylinder to cause the web to contact a greater portion of the circumferential surface of the cylinder than it would in the absence of the air pressure, the air pressure being suction applied between the web and the cylinder and positive air pressure applied on the opposite side of the web to the cylinder.
2. A method according to claim 1 wherein the positive air pressure is air from the suction subsequently pressurized.
3. A method according to claim 1 wherein the web is a paper web and the cylinder is a drying cylinder.
4. Apparatus for treating a web including a rotary cylinder around which the web is passed, and means for applying air pressure to the web immediately adjacent the junction of the web and the cylinder to deflect the web and cuase the web to contact a greater portion of the circumferential surface of the cylinder than it would in the absence of the air pressure, the pressure applying means applying suction between the web and the cylinder and applying positive air pressure to the web on the opposite side thereof to the cylinder.

Claims (4)

1. A method of treating a web including passing the web around a rotary cylinder, and deflecting the web by air pressure applied to the web immediately adjacent the junction of the web and the cylinder to cause the web to contact a greater portion of the circumferential surface of the cylinder than it would in the absence of the air pressure, the air pressure being suction applied between the web and the cylinder and positive air pressure applied on the opposite side of the web to the cylinder.
2. A method according to claim 1 wherein the positive air pressure is air from the suction subsequently pressurized.
3. A method according to claim 1 wherein the web is a paper web and the cylinder is a drying cylinder.
4. Apparatus for treating a web including a rotary cylinder around which the web is passed, and means for applying air pressure to the web immediately adjacent the junction of the web and the cylinder to deflect the web and cuase the web to contact a greater portion of the circumferential surface of the cylinder than it would in the absence of the air pressure, the pressure applying means applying suction between the web and the cylinder and applying positive air pressure to the web on the opposite side thereof to the cylinder.
US00178361A 1971-09-07 1971-09-07 Apparatus for and method of treating a web Expired - Lifetime US3733711A (en)

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Cited By (25)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3874997A (en) * 1973-03-21 1975-04-01 Valmet Oy Multiple cylinder drier in a paper machine
JPS51119279U (en) * 1975-03-24 1976-09-28
US4183451A (en) * 1977-10-14 1980-01-15 Lindauer Dornier Gesellschaft Mbh Equipment for transferring an unstable run of material from a processing machine to a tenter chain
US4190964A (en) * 1977-03-19 1980-03-04 J. M. Voith Gmbh Web drying section for paper machine
US4231164A (en) * 1978-08-31 1980-11-04 Eastman Kodak Company Apparatus and method for uniformly heating or cooling a moving web
WO1982001410A1 (en) * 1980-10-10 1982-04-29 Kodak Co Eastman Method and apparatus for changing the temperature of a moving continuous web
US4369584A (en) * 1981-04-16 1983-01-25 W. R. Grace & Co. Preventing air film between web and roller
DE3236576A1 (en) * 1982-10-02 1984-04-05 J.M. Voith Gmbh, 7920 Heidenheim AIR GUIDE BOX FOR THE DRYING SECTION OF A PAPER MACHINE
US4441263A (en) * 1979-11-20 1984-04-10 Valmet Oy Device in the drying section of a paper machine
US4462169A (en) * 1982-02-19 1984-07-31 W. R. Grace & Company Web dryer solvent vapor control means
US4516330A (en) * 1980-12-12 1985-05-14 Valmet Oy Method and apparatus for the drying section of a paper machine
US4566946A (en) * 1982-11-02 1986-01-28 Valmet Oy Transfer arrangement for guiding the paper web from the press section of a paper machine to it's drying section
WO1987005063A1 (en) * 1986-02-21 1987-08-27 Beloit Corporation Preventing sheet flutter in paper web dryers
EP0239950A1 (en) * 1986-04-03 1987-10-07 Flakt Ross Inc. System for drying paper and nozzle for use therin
EP0313806A1 (en) * 1987-10-28 1989-05-03 Hilmar Vits Process and apparatus for stabilizing the flatter of edges of free moving webs guided over cylinders
US4862600A (en) * 1987-05-08 1989-09-05 Angelo Cremona & Figlio S.P.A. Opposed belt drier for wood veneers
US4988471A (en) * 1989-09-15 1991-01-29 Sano, Inc. Apparatus and method of forming a continuous layer of thermoplastic material
AT395447B (en) * 1988-03-10 1992-12-28 Voith Gmbh J M METHOD FOR DRYING A MATERIAL RAIL AND DEVICE FOR CARRYING OUT THIS METHOD
US5416984A (en) * 1993-11-18 1995-05-23 Heidelberg Druckmaschinen Ag Apparatus and method for deflecting a web
US5426535A (en) * 1993-07-29 1995-06-20 Eastman Kodak Company Apparatus for removing air from between a master magnetic medium and a slave magnetic medium preceding anhysteretic transfer of signals from master to slave
EP0679849A2 (en) * 1994-04-30 1995-11-02 Kabushiki Kaisha Seibu Giken Method and apparatus for dehydrating and drying a wet article
US5475934A (en) * 1993-02-19 1995-12-19 Valmet Paper Machinery, Inc. Method and device for ensuring the run of the web in the multi-cylinder dryer of a papermachine
US5522151A (en) * 1995-01-27 1996-06-04 Beloit Technologies, Inc. Single tier dryer section with dual reversing rolls
US20030175430A1 (en) * 2001-10-29 2003-09-18 Fuji Photo Film Co., Ltd. Coating method and apparatus
US20040261637A1 (en) * 2003-06-26 2004-12-30 Yukio Kobayashi Method and aqueous gravure printing and apparatus therefor

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2777213A (en) * 1952-07-02 1957-01-15 Dungler Julien Supporting and transporting means for web or sheet material in nozzle driers
US3316657A (en) * 1965-10-23 1967-05-02 Huyck Corp Air deflector utilizing coanda effect
US3384973A (en) * 1966-06-09 1968-05-28 Svenska Flaektfabriken Ab Ventilating dryers
US3406464A (en) * 1967-05-09 1968-10-22 Huyck Corp Ventilation system for a papermaking machine
US3633284A (en) * 1969-07-07 1972-01-11 Dominion Eng Works Ltd Web drying

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2777213A (en) * 1952-07-02 1957-01-15 Dungler Julien Supporting and transporting means for web or sheet material in nozzle driers
US3316657A (en) * 1965-10-23 1967-05-02 Huyck Corp Air deflector utilizing coanda effect
US3384973A (en) * 1966-06-09 1968-05-28 Svenska Flaektfabriken Ab Ventilating dryers
US3406464A (en) * 1967-05-09 1968-10-22 Huyck Corp Ventilation system for a papermaking machine
US3633284A (en) * 1969-07-07 1972-01-11 Dominion Eng Works Ltd Web drying

Cited By (32)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3874997A (en) * 1973-03-21 1975-04-01 Valmet Oy Multiple cylinder drier in a paper machine
JPS51119279U (en) * 1975-03-24 1976-09-28
JPS5335352Y2 (en) * 1975-03-24 1978-08-29
US4190964A (en) * 1977-03-19 1980-03-04 J. M. Voith Gmbh Web drying section for paper machine
US4183451A (en) * 1977-10-14 1980-01-15 Lindauer Dornier Gesellschaft Mbh Equipment for transferring an unstable run of material from a processing machine to a tenter chain
US4231164A (en) * 1978-08-31 1980-11-04 Eastman Kodak Company Apparatus and method for uniformly heating or cooling a moving web
US4441263A (en) * 1979-11-20 1984-04-10 Valmet Oy Device in the drying section of a paper machine
WO1982001410A1 (en) * 1980-10-10 1982-04-29 Kodak Co Eastman Method and apparatus for changing the temperature of a moving continuous web
US4516330A (en) * 1980-12-12 1985-05-14 Valmet Oy Method and apparatus for the drying section of a paper machine
US4369584A (en) * 1981-04-16 1983-01-25 W. R. Grace & Co. Preventing air film between web and roller
US4462169A (en) * 1982-02-19 1984-07-31 W. R. Grace & Company Web dryer solvent vapor control means
DE3236576A1 (en) * 1982-10-02 1984-04-05 J.M. Voith Gmbh, 7920 Heidenheim AIR GUIDE BOX FOR THE DRYING SECTION OF A PAPER MACHINE
US4566946A (en) * 1982-11-02 1986-01-28 Valmet Oy Transfer arrangement for guiding the paper web from the press section of a paper machine to it's drying section
WO1987005063A1 (en) * 1986-02-21 1987-08-27 Beloit Corporation Preventing sheet flutter in paper web dryers
EP0239950A1 (en) * 1986-04-03 1987-10-07 Flakt Ross Inc. System for drying paper and nozzle for use therin
US4716660A (en) * 1986-04-03 1988-01-05 Hercules Incorporated Unifelt air suction system
US4862600A (en) * 1987-05-08 1989-09-05 Angelo Cremona & Figlio S.P.A. Opposed belt drier for wood veneers
EP0313806A1 (en) * 1987-10-28 1989-05-03 Hilmar Vits Process and apparatus for stabilizing the flatter of edges of free moving webs guided over cylinders
AT395447B (en) * 1988-03-10 1992-12-28 Voith Gmbh J M METHOD FOR DRYING A MATERIAL RAIL AND DEVICE FOR CARRYING OUT THIS METHOD
US4988471A (en) * 1989-09-15 1991-01-29 Sano, Inc. Apparatus and method of forming a continuous layer of thermoplastic material
US5475934A (en) * 1993-02-19 1995-12-19 Valmet Paper Machinery, Inc. Method and device for ensuring the run of the web in the multi-cylinder dryer of a papermachine
US5426535A (en) * 1993-07-29 1995-06-20 Eastman Kodak Company Apparatus for removing air from between a master magnetic medium and a slave magnetic medium preceding anhysteretic transfer of signals from master to slave
US5416984A (en) * 1993-11-18 1995-05-23 Heidelberg Druckmaschinen Ag Apparatus and method for deflecting a web
EP0679849A3 (en) * 1994-04-30 1996-04-03 Seibu Giken Kk Method and apparatus for dehydrating and drying a wet article.
EP0679849A2 (en) * 1994-04-30 1995-11-02 Kabushiki Kaisha Seibu Giken Method and apparatus for dehydrating and drying a wet article
US5522151A (en) * 1995-01-27 1996-06-04 Beloit Technologies, Inc. Single tier dryer section with dual reversing rolls
US20030175430A1 (en) * 2001-10-29 2003-09-18 Fuji Photo Film Co., Ltd. Coating method and apparatus
US6818062B2 (en) * 2001-10-29 2004-11-16 Fuji Photo Film Co., Ltd. Coating method and apparatus
US20050019499A1 (en) * 2001-10-29 2005-01-27 Fuji Photo Film Co., Ltd. Coating method and apparatus
US20040261637A1 (en) * 2003-06-26 2004-12-30 Yukio Kobayashi Method and aqueous gravure printing and apparatus therefor
US7059244B2 (en) * 2003-06-26 2006-06-13 Nakamoto Packs Co., Ltd. Method for aqueous gravure printing and apparatus therefor
CN100408328C (en) * 2003-06-26 2008-08-06 中本包装株式会社 Method for aqueous gravure printing and apparatus therefor

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