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Publication numberUS3861996 A
Publication typeGrant
Publication dateJan 21, 1975
Filing dateMar 16, 1971
Priority dateMar 17, 1970
Also published asDE2112395A1
Publication numberUS 3861996 A, US 3861996A, US-A-3861996, US3861996 A, US3861996A
InventorsGerhard Walter Dorfel
Original AssigneeAhlstroem Oy
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Paper web transfer system carrying the web from forming wire to press section
US 3861996 A
Abstract
Apparatus for transferring a paper web from a papermaking machine forming wire to a press section. A suction pick-up roll located adjacaent the forward run of the forming wire is wrapped in part by a first endless pick-up felt which picks the web up from the forming wire and carries it through the first press nip of the press section. Prior to contacting the paper web the first felt passes through a press nip (for liquid removal) formed between the suction pick-up roll and a press roll. A second felt (i.e., lower support felt) contacts the web carried by the first pick-up felt between the forming wire and press section.
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Description  (OCR text may contain errors)

Umted States Patent [191 [111 3,861,996 Dorfel Jan. 21, 1975 [54] PAPER WEB TRANSFER SYSTEM 2,709,398 5 1955 Beachler 162/306 CARRYING THE WEB FROM FORMING 3,207,657 9/1965 Wagner et al. 162/361 X 3,526,574 9/l970 Beachler,etal..... 162/358 X WIRE T0 PRESS SECTION 3,629,056 l2/l971 Forrest 162/305 75 Inventor: Ge h d W lter D fl 1 fg "16h" f f g FOREIGN PATENTS OR APPLICATIONS [73] Assigneez A. Ahlstrom Osakeyhtio, 565,550 ll/l958 Canada 162/360 Noormarkhv Finland Primary Examiner-S. Leon Bashore [22] Filed: Mar. 16, 1971 Assistant ExaminerRichard H. Tushin [21] Appl No 124 766 Attorney, Agent, or Firm-Brooks, Haidt & Haffner [30] Foreign Application Priority Data [57] ABSTRACT Mar 7 1970 Finland 714/70 Apparatus for transferring a paper web from a papermaking machine forming wire to a press section. A [52] Cl. 162/274 162/306 162/358 suction pick-up roll located adjacaent the forward run 162/366 of the forming wire is wrapped in part by a first end- Inti. less pick-Up felt picks the Wb up from the [58] Field of 'i; 16 210 360 forming wire and carries it through the first press nip "fag of the press section. Prior to contacting the paper web the first felt passes through a press nip (for liquid re- [56] References Cited moval) formed between the suction pickup roll and a press roll. A second felt (i.e., lower support felt) UNITED STATES PATENTS contacts the web carried by the first pick-up felt belii ii a1 162/113 x en the forming wire and press section. 1 spaug 2,694,346 11/1954 Goodwillie 162/306 X 1 Claim, 6 Drawing Figures PATENTEDJANZHQYB 3.86139 SHEETIUF 2 Fig. 3

PATEMED 3.861.996

SHEET 2 BF 2 Fig. 5

PAPER WEB TRANSFER SYSTEM CARRYING THE WEB FROM FORMING WIRE TO PRESS SECTION BACKGROUND OF THE INVENTION 1. Field of the Invention The invention relates to the field of pressing a fiber web in a press section.

2. Description of the Prior Art Various arrangements have been introduced previously for the pressing of a paper web. US. Pat. No. 2,911,040 introduces a pressing part which is situated at a distance from the pick-up roll in the moving direction of the paper. The arrangement introduced in this patent has, however, the disadvantage that the part of the felt between the pick-up point and the first pressing point is under tension and the wet paper web stretches in this area. This takes place, in spite of the fact that the pick-up roll and the pressing roll rotate at the same peripheral speed, since slipping of the felt occurs at the pick-up roll. Due to stretching of the paper web, an orientation of the fibers takes place in the longitudinal direction which diminishes the longitudinal elasticity of the finished paper. Owing to the different longitudinal and transversal orientations of the fibers the finished paper sheet will not remain even.

SUMMARY OF THE INVENTION According to the invention the pick-up felt is pressed against the pick-up roll by means of a press roll to eliminate slipping of the felt and stretching of the web.

The paper produced in accordance with the invention has better elasticity than paper manufactured by prior known methods.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 illustrates schematically a press section of a paper machine for carrying out the method according to the invention, and

FIGS. 2-6 illustrate schematically alternative embodiments of the press section.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1, 13 is the wire of the web-forming part, from where the suction roll 2 working as a pick-up roll moves the paper web 12 with the suction effect of the roll to the endless felt 8. The suction roll, together with roll 1, forms a press nip through which the felt 8 runs. The felt and the paper web run to roll 3 at a distance from roll 2; roll 3 and roll 4 together form another press nip, where liquid is pressed out of the paper web 12. Thereafter the paper web is separated from the felt and it runs to the next pressing point which is formed by roll 4 together with roll 5. A suitable roll combination is a suction roll 3, a stone roll 4, and a grooved roll 5. The direction of the movement of the paper web is illustrated by arrows.

Because the felt runs through two press nips at a distance from each other, with no slipping occuring at the pressing points, it is possible, by choosing a somewhat lower peripheral speed for roll 3 than for roll 2, to obtain a longitudinal shrinking of the felt and thus also of the paper web between the pressing points, in which case the elasticity of the finished paper increases. FIG. 1 also illustrates the drying and cleaning devices of the endless felt 8 and the respective devices 16 of the pressing felt l4.

To keep the felt and the paper track essentially horizontal between the pressing points, an endless, synchronically moving, wire 9 can be placed below them. An arrangement like this is illustrated in FIG. 2. FIG. 5 illustrates a corresponding arrangement in a case in which the rolls 6 and 7 of the supporting wire 9 participate in forming the pressing points.

The felt and the web can be supported in other ways as well. In the application according to FIG. 3, a suction box 10 has been fitted above the felt to keep the felt part horizontal. In the case according to FIG. 4, a blowing device 11 has been respectively fitted below the felt; this device creates a cushion of air to support the felt part.

The pair of rolls 1 and 2 forms the so-called washing press of the felt and removes from the felt liquid that has been absorbed by it. Because the paper web is supported between rolls 2 and 3, the felt can be relatively dry there, in which case the proportionate dryness of the paper web, also, will be high after the first pressing point.

According to another embodiment, shown in FIG. 6, the paper web travels from the upper pick-up felt 8 running around the pick-up roll 2, to the lower support felt 9 at the pressing point formed by pressing roll 6, which is inside the lower felt, together with the pick-up felt. The paper track, supported by the lower felt, runs to the next pressing point formed by pressing roll 7, which is inside the lower-felt loop, together with pressing roll 3, onto which the paper web moves following the pressing point. Thus the embodiment of FIGS. 5 and 6 have in common the passage of the upper pick-up felt alone through a press nip, a second press nip through which the web is passed between two felts, and a third nip through which the paper web passes along with the support felt. In both of these cases the web is separated from the felt by appropriate guide means as shown by the arrows and the small rolls for the departing felts 8 and 9 in the two embodiments.

On the straight part of the felt between the pressing points of shrinking, or in certain cases also a so-called microcreping, of the paper web can be obtained which improved the elasticity of the paper. The pick-up roll is a positive one and the pressing roll in contact with it may also be positive. Both or one of the rolls of the pressing point after the straight felt part may be positive. The numbers of revolutions of the first and the second pressing points can be changed without gradation so that the speed of the felt at these points may be the same or greater at the first pressing point than at the second.

Suction rolls, rolls with different coatings, smooth rolls, or grooved rolls, in suitable combinations, can be used as pressing rolls, as in paper machines in general.

What is claimed is:

1. An improved press section in a web forming machine of the type having at least two traveling endless felts for contacting and carrying the web, which includes a pick-up roll urging a pick-up felt against the web for transferring the web to the felt, said pick-up felt passing around said pick-up roll and through a press nip for the pick-up felt defined between a press roll and said pick-up roll, a second press roll opposedly positioned to said pick-up roll and defining a second press nip between said pick-up roll and said second press roll through which the web, said pick-up felt and a support felt pass, the web being carried through said ing the web between said second and third press nips; one roll of each of said second and third press nips constituting a guiding roll for said support felt, and roll means for separating the web from the felt after said third press nip.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US2043351 *Jun 1, 1935Jun 9, 1936Int Cellucotton ProductsMethod of making a tissue paper product
US2204426 *Jun 19, 1936Jun 11, 1940Sandusky Foundry And Machine CPapermaking machine
US2694346 *Mar 25, 1950Nov 16, 1954Beloit Iron WorksWeb transfer assembly
US2709398 *Jun 2, 1950May 31, 1955Beloit Iron WorksSuction transfer assembly with deckle edge control
US3207657 *Jan 22, 1963Sep 21, 1965Huyck CorpMethod and apparatus for making paper by contracting the forming carrier to compact the web
US3526574 *Mar 27, 1967Sep 1, 1970Beloit CorpVacuum transfer device in papermaking machine
US3629056 *Apr 3, 1969Dec 21, 1971Beloit CorpApparatus for forming high bulk tissue having a pattern imprinted thereon
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US4016032 *Apr 14, 1975Apr 5, 1977Valmet OySuction roll for transferring a web away from a press section
US4056433 *Sep 15, 1976Nov 1, 1977Valmet OyAscending twin-wire paper machine without web pick-up
US4059482 *Sep 24, 1975Nov 22, 1977Valmet OyPaper machine pickup and crepe-setting press section
US4075056 *Mar 8, 1977Feb 21, 1978Beloit CorporationPress section structure
US4086131 *May 6, 1975Apr 25, 1978Beloit CorporationMethod for pressing bagasse webs
US4110156 *Jun 6, 1977Aug 29, 1978Escher Wyss LimitedCompact press at the web transfer position of a paper making machine
US4113557 *Apr 14, 1977Sep 12, 1978Valmet OyPaper manufacturing structure particularly for detaching a web from a wire
US4163688 *Apr 25, 1977Aug 7, 1979Valmet OyApparatus for dewatering in a paper machine
US4172759 *Sep 12, 1977Oct 30, 1979Valmet OyPaper-machine structure and method for subjecting a web to suction
US4188262 *Feb 23, 1977Feb 12, 1980ValmetMethod for dewatering paper in a paper machine press section
US4197158 *Mar 16, 1978Apr 8, 1980Beloit CorporationPaper making machine press section
US4209361 *Apr 25, 1977Jun 24, 1980Valmet OyMethod of multi-nip pressing in a paper machine
US4257844 *Mar 19, 1979Mar 24, 1981Beloit CorporationPress section arrangement
US4285766 *Oct 5, 1979Aug 25, 1981Valmet OyPress method in a paper machine
US4551203 *Apr 2, 1984Nov 5, 1985Valmet OyMethod and arrangement for guiding a paper web from the press section to the drying section
US4792381 *Sep 11, 1987Dec 20, 1988Valmet OyClosed and compact press section of a paper machine with double S shaped path or mirror image thereof
US4909905 *Jun 2, 1987Mar 20, 1990Valmet Paper Machinery Inc.Closed press section of a paper machine and a frame construction for same
US4919762 *Jun 17, 1988Apr 24, 1990Valmet Paper Machinery Inc.Press section and press section/frame construction combination in a paper machine
US5308450 *Apr 15, 1992May 3, 1994Sulzer Escher Wyss GmbhPress section of a papermaking machine
US5431787 *Oct 25, 1993Jul 11, 1995Sulzer-Escher Wyss GmbhPress section of a papermaking machine
US5501775 *Jan 21, 1994Mar 26, 1996J. M. Voith GmbhWet press for a paper making machine
US5520782 *Jan 21, 1994May 28, 1996J. M. Voith GmbhMethod and apparatus for removing water from a web by means of presses
US5639351 *Nov 22, 1994Jun 17, 1997Valmet CorporationPress section of a paper machine, in particular for printing paper qualities
US5670023 *May 27, 1994Sep 23, 1997Voith Sulzer Papiermaschinen GmbhPress of a paper machine for thin papers
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US5792318 *Jul 20, 1997Aug 11, 1998Mancini; RalphMethod to stabilize sheet between press section and dryer section of a paper-making machine
US5820731 *Jun 10, 1994Oct 13, 1998Valmet CorporationMethod and apparatus in a paper or board machine for dewatering the web
US5830321 *Jan 29, 1997Nov 3, 1998Kimberly-Clark Worldwide, Inc.Method for improved rush transfer to produce high bulk without macrofolds
US5865954 *Jun 18, 1997Feb 2, 1999Valmet CorporationMethod for dewatering a web in a paper making machine employing an extended nip press
US5888354 *Apr 2, 1997Mar 30, 1999Valmet CorporationTransfer of a web in a paper machine from a two-felt press nip to a dryer section
US5891308 *Feb 2, 1996Apr 6, 1999Beloit Technologies, Inc.Method of pressing a paper web of tropical hardwood fibers
US5951821 *Sep 25, 1998Sep 14, 1999Valmet CorporationArrangement and method for transferring a web in a paper machine from a two-felt press nip to a dryer section
US6030499 *Mar 20, 1998Feb 29, 2000Valmet CorporationMethod and apparatus in a paper or board machine for dewatering the web
US6090244 *Jan 28, 1998Jul 18, 2000Voith Sulzer Papiermaschinen GmbhPress section
US6228216 *Jul 10, 1998May 8, 2001Kimberly-Clark Worldwide, Inc.Transfer of a cellulosic web between spaced apart transport means using a moving air as a support
US6260287Apr 27, 2000Jul 17, 2001Raffaele ManciniWet web stability method and apparatus
US6368466 *Nov 15, 1995Apr 9, 2002Valmet CorporationPress section of a paper making machine employing an extended nip press
DE3942396A1 *Dec 21, 1989Jun 28, 1990Tampella Oy AbVerfahren und anordnung zum leiten einer faserbahn von einem sieb durch eine pressenpartie
Classifications
U.S. Classification162/274, 162/360.3, 162/306, 162/358.1
International ClassificationD21F1/36
Cooperative ClassificationD21F1/36
European ClassificationD21F1/36