US2083817A - Water extracting device for paper machines and method of making paper - Google Patents

Description

June 15, 1937. BERRY 2,083,817

WATER EXTRACTING DEVICE FOR PAPER MACHINES AND METHOD OF MAKING PAPER Filed May 5, 1955 2 sheets sheet 1 N'-\ n @J zwzz-lser/ E. E. BERRY June 15, 1937.

WATER EXTRACTING DEVICE FOR PAPER MACHINES AND METHOD OF MAKING PAPER Filed May 3, 1935 2 Sheets-Sheet 2 MED U5 Zar/Zfeny Patented June 15, 1937 WATER EXTRACTING DEVICE FOR PAPER MACHINES AND METHOD OF MAKING PAPER Earl E. Berry, new; Wis., assignor to Beloit Iron Works, Beloit, Wis.,' a corporation of Wiscousin Application May .3, l

935; S erialNo. 19,590

- 9 Claims. (01. 92-38) This invention relates to a water extracting device for receiving the wet web ofpaper directly from theforming part of a paper machine,

More specifically this invention relates to an improved form of suction and extraction device for removing moisture from paper webs formed on a cylinder machine without the 'aidof the large number of primary or baby presses heretoforerequired on cylinder. type paperi machines.

The invention also includes" a process for removing water from cylinder for'med paper webs In the conventional multi-cylinder type of paper ,machine,'the pickup felt: is contacted with thetopportion of each cylinder mold to thereby remove. the wet fibrous web from the revolving cylinder. A built-upfibrous 'web is thus caused to adhere to the under side of the-pickup felt. After leaving the last cylindermold, the'web and felt is trained around'a roll positioned at the rearofthe machine and travel back over the cylinder molds. ,I )u'ring its travel back over the 'm'olds;the fibrous web, which'is now on the upper surfacelof'the pickup felt is'covered with .a top felt an d pressed :while between the two felts by.

- means ofjprimar y. press. rolls arranged in batqteri'estqimparta graduallyincreasing pressure a's the-wateris'removed from the web and felt.

Itis essential thatlthe primary pressing action 4 be .ve'ry -jgentle at first and gradually increased 730 .until the web is suflic'iently dry so that it can be subjected-to. high pressures without severe crush- The pheretofore' considered necessary primary pressrolls-have many disadvantageous features,

most" objectionable of which i may be listed as followsz t (1);- High initialexpense to purchase and nstall 1 3 required number'of rollsf.

. (2) High maintenance cost in l'reeping the rolls synchronize-and drive the sets or batteries of ro ll s.- 3 i (5 Passage of wet web through thelarge numk vber of. nips between 'the rolls t'ends todistort and 50 spoil the fiber formation of the web;

(.6) Air often enters between the web and Y 'feltsand punctures or blows the wbiduring the-pressing operation between the lrolls. (7) Multi-ply webs often separate at the plies 55 as they-pass betweenthe nips of the rolls be- I i i ground and'in replacing worn rubber covers for web by pressure at the nip of the rolls, and

cause the web has to conform with the radius of the rolls.

I have now provided a. water extracting device to replace the primary press rolls in cylinder type paper machines. ,My 7 device removes la ge amounts of thewater from the cylinder formed web bysuction and thereafter presses the web against the suctiondevice itself to remove further quantities of water so that the web may be subjected to high pressures without damage or maybe directly passed to the driers. In accordance with my invention, I provide a suction roll withsmali holes drilled through its periphery and spaced as close together as possible. The holes are so shaped and spaced, as will be hereinafter described,to reduce the resistance of entering air 'and water as much as possible. The' suctionroll is provided with the usual type of floating head suction manifold but is arranged so as to h ave a relatively wide suetion 'ar'ea. Apress roll is mounted above the suction roll so that the nip between the rolls occurs either inside the suction area or justat, or beyond the end of the suction area, as defined by the suction manifold within the perforated drum.

This combination suction cylinder type paper machine and the pickup felt is trained around the suction roll and passe'sbetween the nip of the press roll and suction roll.

' suction roll'to remove further quantities of water and sufficientlyform the web so that it may be passed directly to heavy duty presses or to the drying cylinders. Since the felt is somewhat V drum and press rollis mounted after the last cylinder mold on the dried by 'the precedi'ng suction treatment; it absorbs water which has beenliberated from the thereby aids the drying of the web.

The suction-,roll must be provided with small diameter holes soithat the web and felt are not suckedor pressed. into'the holes and thus dam-4 aged. The entry of theweb and felt into the holes would also space the weband felt somewhat from' the toppress roll and thereby make a the application-of pressure less effective.

In'rny :copendingapplication entitled Cylinder paper machine and method of making paper, Serial No.19,5 91, filed of even date here-V.

with, I have described and claimed a cylinder type of paper making machine in which a P up felt emoves the fibrous mats from the cylinder molds, carries the mats through a water extracting device according to'this invention and immediately thereafter transfers the so formed fibrous web to another felt or carrier before the web canreabsorb moisture from the pick-up felt.

' In my copending application entitled Cylinder paper machine and process of making paper, Serial No. 26,181, filed June 12, 1935, I have described and claimed a cylinder type of paper making machine having the pick-up felt travelling over the cylinder molds to remove the fibrous mats therefrom and carry the mats through a water extracting device according to this inven tion to form a fibrous web therefrom. The direction of travel of the web is reversed after passage through the water extracting device and the web is carried by another felt or carrier with the pick-up felt side of the web exposed.

It is therefore an object of this invention to provide a water removing device for cylinder formed webs which dispenses with the heretofore necessary primary presses, extractor rolls and the like, normally used on this type of paper machines.

Another object of this invention is to provide a. water extracting device including a suction drum and co-operating press roll for removing water from the pickup felt and fibrous web formed on cylinder type paper machines.

A further object of this invention is to provide a suction-roll with holes of a sufficiently small size and so closely spaced that a cylinder formed fibrous web may be subjected thereon, without damage, to suction of a high degree' A further object of this invention is to provide a process for removing water from cylinder formed fibrous webs without the aid of primary presses and extractor rolls.

A further object of this invention is to provide a process for removing water from newly formed wet fibrous webs by suction and subsequent pressure onthe suction device.

Other and further objects of this inventio will be apparent from the following detailed description of the annexed sheets of drawings which disclose a preferred embodiment of the invention.

. On the drawings:

Figure l is a fragmentary elevational view with parts in vertical cross section of a cylinder type paper machine showing the last cylinder mold and the water removing device of this invention.

Figure 2 is an enlarged plan view of the outside periphery of the suction roll drum used in this invention illustrating the manner in which the roll is perforated.

Figure 3 is a vertical cross sectional view of the suction roll drum showing the holes drilled therethrough.

Figure 4 is a broken elevational view with parts in vertical cross section of an alternative form of cylinder type paper machine embodying the water removing device of this invention and illustrating-the manner in which a top' felt may be used on the machine if desired.

Figure 5 is an enlarged fragmentary cross sectional view of a suction slice.

As shown on the drawings:

In Figures 1 and 4, the reference numeral l0 designates cylinder molds of the conventional type rotating in vats ll containing the paper stock. A pickup felt I2 is directed over the top of the cylinder molds Ill and is pressed against the periphery of the cylinder molds by coucher rolls l3 of the conventional type. The fibrous web formed on the cylinder molds i0 is thustransferred to the pickup felt II which travels toward the rear of the machine as indicated and around a roll [4.

The water extracting device of this invention is mounted above the roll 14 between the vertical legs l5 and I6 of a frame structure. The water removing device comprises a suction roll I! and a co-operating press roll I8. The suction roll i1 is mounted at its ends in bearings l9 and is connected through a hollow trunnion 20 located in one or both ends of the roll to a drain pipe 2| which is connected with a suction pump (not shown). A suction box 22 is mounted within the roll I! and carried by the trunnion 20. The suction box 22 is provided with a floating head 22a which rubs or bears against the inner periphery of this roll to define a suction area indicated generally at A. The suction roll may be of any suitable construction known to the art such as the roll described in my United States Patent No. 1,679,598. However, in the present installation, the floating head 22a defines a larger suction area than is customary in suction rolls. Furthermore, the holes 23 (Figs. 2 and 3) drilled through the roll I! are of smaller diameter and are spaced closer together than in the customary suction roll. The holes 23 are countersunk for about an eighth of an inch as shown at 24. Whereas the holes of the customary suction roll average about of an inch in diameterand are countersunk on the surface to provide openings of inch to inch in diameter, the holes of the suction roll used in this invention are reduced to a diameter of about to inch with the largest diameter of the countersunk portion being about ito 1 3' inch. The holes are arranged so as to provide a minimum of solid surface on the roll. Because the holes are small and are close together, the countersinks 24 can be very gradual to eliminate the vortex draining effect produced by larger holes, spaced further apart and provided with flat eountersinks to reduce the land area. between the holes which reduces the resistance to drainage.

As shown in Fig. 2, the holes are arranged in and the rows are staggered so that the center of a hole in one row is positioned at a point mid-way between the holes in an azfiacent row.

When holes having a diamter of inch are drilled in the suction drum, the centers of the holes in each row are spaced about .28 inch apart while the centers of the adjacent rows are spaced about .254 inch apart. The tops of the holes are then countersunk to have a surface diameter of about inch. This arrangement leaves a minimum of solid metal between each hole and at the same time provides a rigid structure. In this manner, all portions of the pickup felt and fibrous web passing over the suction area of the suction roll are subjected to suction. At the same time, the holes are of comparatively small diameter and the felt and web are not pressed away from the top press roll or damaged by being sucked into these holes.

If desired the suction roll I! may be covered with a resilient covering or cushion which is perforated in the manner described and claimed in my United States Patent No. 1,947,636.

30 horizontal leg 31 below the, suction roll.

The press roll it is mounted above the suction roll 11 in horizontal bearing brackets 25 eccentricallypivoted at 26 'on a supporting angle 21 carried by the vertical legs l6 of the frame strucr; ture. The roll i8 is thus adjustable horizontally relative to the suction roll 11 by a rotation of the eccentric pivot 26. The brackets 25 have an extending arm portion 28 thereon for receiving a link rod 29 which extends vertically toward the bottom of the machine and is secured at 30 to a horizontal arm 3! pivoted at 32 to the vertical leg I5 of the frame structure. The lever arm 3! may have weights 33 mounted thereon for holding the press roll 58 against the suction roll i1 with any desired pressure which may be regulated by a movement and/or replacement of the weight 33. It is obvious that other pressure adjusting devices may be used in place of the link arm arrangement shown. i For raising the roll W, a device 36 is provided comprising boltsscrewed through the bracket arms and adapted to engage the supporting roll l1 sothat the water drops into the save-all angle 21 as shown.

A save-alltray 35 is mounted around the lower 25 portion of the suction roll I! and is adapted to 1 receive water removed from the web andfelt by the pressing operation. This, save-all tray is preferably V-shaped as shown having a vertical,

. leg 36 extending behind the suction roll H and a Adjacent the end of the leg 31 is mounted a wiping device 38 adapted to scrape against the periphery of the suction roll. The wiping device '38 is pivoted .at 39 'and 'may be urged against the roll 3 IT by any suitable counterbalance or spring means. A thin metal strip 40 is carried by the wiping member 38 to direct any of the water removed from the periphery of the suction roll into press roll to rub off anywater carried by the p roll. -The angle 4| and the rubber 'strip 43 extend across thewidth of the roll l8 so that any water scraped therefrom may drop into the saveall tray 35-, which also extends beyond the length ofthe suction roll I 1. V

50' In the arrangement shown in Figure 1. the

water removing device is operated without the use of a top press felt. In Figure 4, however, a top press felt 45 is directed overthe suction. roll i1v and travels with the pickup felt i2 and fibrous web thereon between thenip' of the suction and press rolls. It is then directed away from the fibrous-web carried bythe pick up felt l2 and over guide rolls 46. The top felt 45 may be guided by means of an adiustable guide roll 41 tomeet the pick up felt and fibrous web thereon at varying points on the suction roll and vary the amount of wrap of this felt around the roll. Thus if the pickup felt follows the path indicated in solid line it contacts the fiibrous web on the pickup felt I? at a point about midway between the ends of the suction zone A. However, if the felt guide roll 81 is raised to the position indicated in dotted line the top felt 45 merely contacts the fibrous web on the pickup felt 62 at the top portion of the roll and travels with the web through the nip between the rolls.

It is desirable tovarythe amount of wrap of the top felt around the suction roll depending upon the weight and porosity of the paper being produced. When light weight papers are run over the suction area, the amount of wrap of the J top felt around the suction roll should be increased to cover all or most of the suction area to seal the same, tlfereby permitting the pulling of a higher vacuum on the sheet to more thoroughly 5 dry the sheet. When heavier and less porous #35 is guided over the machine by means of guide rolls 48.

Since water is pressed up through the top felt it as it passes through the nip between the rolls, a resilient plain slice 49 may be positioned above the suction roll i1 to wipe against the felt 45. The plain slice 49 extends across the width of the felt and prevents the water from running back 2f on the felt and being reabsorbed by the sheet.

It directs this water over the edges of the'felt and tray 35. The plain slice 49 may be carried by suitable journals 50 mounted at its ends in the 25 frame structure. i A suctionslice 5i (Figure 5) may be used in place of the plain slice49. This slice 5| is vertically adjustable-at each end on supports 52 by means of nuts 53 and. 54 threaded on the supports 30 52 and engaging lugs 55 and 56 respectively extending from the suction manifold 51 of. the slice. The. supports 52 extend through the lugs 55 and 55 and are carried by the frame structure of the machine. A lip 58, having a passageway 59, ora plurality of such passageways extending therethrough is mounted at one'end in the manifold .51, as shown, and projects into the space between the'press roll I 8 and the suction drum l1. This lip 58, likethe plain slice 49,- 40 extends. across the width of the top felt 45 but instead of merely directing the water on the top felt over the edges ofthe felt it draws the water throughthe passageways therein into the suction manifold 51. The manifold 51 is connected 45 at one or -both endswith a suction drain line (notjshown) From the above description. it will be understood that 'I have now provided a combination suction and press device for removing water from cylinder formed fibrous .webs without crushing or distorting the web so that a sheet of maximum strength per unit weight is obtained. The small holes in the suction roll permit pressure to be exerted on the web as it passes over. the roll for 55 the removal of further quantities of water without damaging the Web or felt. These small holes also preventthe web and felt from being drawn away from the top roll. The combination suction and press rolls therefore sumcien'tly remove the 60 water from the wet web Without damage and without the use of the large number of extractor rolls, primary press rolls and'the like water removing means used heretofore.

The wet web emerging from the last cylinder mold of a cylinder type paper machine generally contains about 88% by-weight of water, while the pickup felt may contain even higher amounts depending upon the pressure exerted by the 70 coucher rolls. The suction roll part of this invention before the nip of the press part reduces the water content'of the web about 10% to about 78% water. The pressure roll then squeezes out further quantities of water drying the web to 75 about 70% water or less depending upon the pressure exerted. The web is thus suificiently dried and formed to be passed directly to the heavy duty presses or to the driers.

The suction roll as shown on the drawings has a very wide suction area defined by a floating head on the suction box. This construction makes it possible to pull a vacuum of 12 inches of mercury or more without deflecting the roll or looking the suction box against the roll. The 7 high vacuum combined with the large suction area makes possible a very large extraction of water before the pressing operation.

I am aware that many changes may be made and numerous details of construction may be varied through a wide range without departing from the principles of this invention and I, therefore, do not purpose limiting the patent granted hereon otherwise than necessitated by the prior art.

I claim as my invention:

1. In a cylinder type paper machine, in combination, a plurality of cylinder molds, a plurality of couch rolls cooperating with said cylinder molds, a pickup felt cooperating with said cylinder molds and couch rolls to receive the fibrous webs formed on the cylinder molds, a suction roll positioned after the last cylinder mold, a relatively wide floating head in said suction roll to define a wide suction area on the on the pickup felt at a point on the suction roll near-the end of the suction area thereof, means for adjusting the horizontal position of said press roll relative to said suction roll, means for adjusting the pressure between the rolls, a water collecting trough around the lower portion of said suction roll, an apron member extending axially across said press roll and beyond the ends of the press roll for removing. water from the press roll and directing the same into the trough, a wiper device urged against the bottom of said suction roll for removing water therefrom and means associated with said wiper device for directing the water removed thereby into the trough.

2. The process of extracting water from wet fibrous webs just subsequent to their formation on a cylinder paper machine which comprises conveying a pick up felt carrying the newly formed wet web removed thereon directly from the cylinders away from the cylinders, wrapping the felt and web around the suction area of a suction roll, wrapping a top felt around the suction area of the roll to cover the wet web thereon, sucking water from the web and pick up felt as they pass over the suction area, and squeezing additional amounts of water therefrom;

3. In a cylinder paper machine including cylinder molds and a pick up felt for receiving a wet fibrous web therefrom, a suction drum located after the last cylinder mold in spaced relation therefrom, a press roll urged thereagainst, means for directing the pick up felt and web around said drum and between the nip of the roll and drum, a top felt and an adjustable top felt guide roll to wrap the top felt over the web around the aoaasrr drum for a predetermined amount of travel thereover.

4. The process of extracting water from the wet, soggy, cylinder-formed fibrous mats removed from the cylinder molds on a pick-up feitwhich comprises conveying the mat on the 'felt away from the cylinder m'olds, wrapping the felt with the mat thereon around the suction area of a suction roll to remove water from the mat by suction, contacting the mat with a top felt, and pressing the two felts together with the mat therebetween to remove more water therefrom and thereby form a self-supporting fibrous web from the mat.

5. In a cylinder type paper making machine, a pick-up felt for directly receiving the wet, soggy, fibrous mats from the cylinder molds, a directing roll positioned after the last cylinder mold for receiving the pick-up felt therearound, a water extracting device above the directing roll for receiving thereover the mats and felt from the directing roll, a top felt for covering said mats on the pick-up felt as they pass over the water extracting device, and means for pressing the top felt and the pick-up felt together with the mats therebetween.

6. The process of removing water from the wet, soggy mats picked up by a felt from the cylinder molds of a cylinder type paper machine which comprises training the pick-up felt with the mats thereunder around a guide roll positioned after the last cylinder mold, directing the pick-up felt upwardly from the guide roll around a suction drum, covering the fibrous mats with a top felt as they pass around the suction drum, and extracting water from the fibrous mats through the pick-up felt by suction to form a fibrous web from the mats.

7. The process of extracting water from wet fibrous webs just subsequent to their formation on a paper machine which comprises pickingup the wet fibrous web on a pick-up felt directly from the'forming surface of the paper machine, conveying ,the web on the felt away from the forming surface, wrapping said pick-up felt with the web thereon around the suction area of a suction roll, wrapping a top felt around part of the suction roll to cover the wet web thereon,

sucking water from the web and pick-up felt as they pass over the suction area of the roll, and squeezing additional amounts of water therefrom.

8. In a paper machine, a fibrous web forming part, a pick-up felt for receiving a wet fibrous web therefrom, a suction drum located after the fibrous web forming part of the machine, a press roll urged against said suction roll, means for directing the pick-up felt and web around said drum and between the nip of the roll and drum, a top felt for covering said web, and an adiustable top felt guide roll to wrap the top felt over the web around the drum fpr a predetermined amount of travel thereover.

9. In a paper machine having a fibrous web forming surface, a pick-up felt for receiving a wet, soggy web from the forming surface, a suction roll spaced from said forming surface, said suction roll having a wide suction head therein for defining a large suction area on the periphery of the roll, means for training the felt with the web, thereon over said suction area, said suction roll being perforated with closely spaced holes of small diameter so that the web and pick-up felt will not be deformed as they rolls relative to the suction area, means for adjusting the pressure between the rolls, and a wiper device urged against the periphery of the suction roll ahead of the suction area to remove water therefrom.

EARL E. BERRY.

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