US3775242A

US3775242A - Single endless strands as support surfaces in various sections of papermaking machine having integrated convolutions

Info

Publication number: US3775242A
Application number: US00201323A
Authority: US
Inventors: F Orbison; H Helland
Original assignee: Appleton Mills
Current assignee: Appleton Mills
Priority date: 1971-11-23
Filing date: 1971-11-23
Publication date: 1973-11-27
Anticipated expiration: 1990-11-27
Also published as: CA981954A

Abstract

A porous supporting structure for a fluid-impregnated web or sheet which includes a series of supporting surfaces each of which is composed of a group of adjacent, parallel, machine direction convolutions of a single strand mounted to travel in a path over a roll assembly in a series of repeating convolutions. The supporting surfaces are integrated by intermingling a group of convolutions of one web supporting surface with a second group of convolutions of a second web supporting surface at an unsupported lease area. The web is conveyed from the first web supporting surface across the lease to the second web supporting surface to provide continuous support for the web. By varying the relative speed of travel of the strands forming the various web supporting surfaces, or by varying the angularity between the two integrated web supporting surfaces, the finish effects and degree of dewatering of the web can be varied.

Description

United States Patent [19 Orbison et a1.

[451. Nov. 27, 1973 [75] Inventors: Frank H. Orbison; Howard M.

I-Ielland, both of Appleton, Wis.

[73] Assignee: Appleton Mills, Appleton, Wis.

[22] Filed: Nov. 23, 1971 [21] Appl. No.: 201,323

[52] US. Cl 162/208, 34/162, 34/236, 100/118, 162/308, 162/350, l62/DIG. 1,

[51] Int. Cl. ..D21f 1/10, D21f1/26, 865g 15/12 [58] Field of Search 198/91, 99, 76, 190,

197, 202, 208, 308, 350, DIG. 1; 34/236, l62;100/118;226/170,ll1

FOREIGN PATENTS OR APPLICATIONS 634,224 1 3/1950 Great Britain 198/190 Primary Examinen s. Leon Bashore Assistant ExaminerRichard I-I. Tushin Att0rneyAndrus, Sceales, Starke & Sawall [5 7] ABSTRACT A porous supporting structure for a fluid-impregnated web or sheet which includes a series of supporting surfaces each of which is composed of a group of adjacent, parallel, machine direction convolutions of a single strand mounted to travel in a path over a roll assembly in a series of repeating convolutions. The supporting surfaces are integrated by intermingling a group of convolutions of one web supporting surface with a second group of convolutions of a second web supporting surface at an unsupported lease area. The web is conveyed from the first web supporting surface across the lease to the second web supporting surface to provide continuous support for the web. By varying the relative speed of travel of the strands forming the various web supporting surfaces, or by varying the angularity between the two integrated web supporting surfaces, the finish effects and degree of dewatering of the web can be varied.

11 Claims, 2 Drawing Figures SINGLE ENDLESS STRANDS AS SUPPORT SURFACES IN VARIOUS SECTIONS OF PAPERMAKING MACHINE HAVING INTEGRATED CONVOLUTIONS BACKGROUND OF THEINVENTION In a papermaking machine diluent water used to prepare cellulose fibers for sheet formation must be removed and the water carried by the formed sheet must be extracted, and most of the water absorbed by the pressed sheet must be driven out by heat in order to create a paper product. While these water removing operations are taking place, the paper. web or sheet must be supported and conveyed by a structure which satisfies the water removal requirements. Since gravity, vacuum, pressure absorption, and vaporization are successively used to control the appropriate rate of maximum water removal and also to satisfy the finish or smoothness requirements of the sheet, the structures which support and convey the paper web control the success of the papermaking operation.

The papermaking machine has three sections: forming, pressing and drying. Each section has distinctive supporting and conveying structures which provide different water removing rates and different paper surface smoothness influences in order to simultaneously provide for the imposed process and product requirements described above. The structures used to support and convey the paper web in each of these sections are respectively Fourdrinier wires or forming fabrics, wet felts and dryer felts.

Each of these distinctive structures has functional and practical shortcomings. Metal wires wear, or because of their fragile structure, become damaged, resulting in frequent and costly replacement. Wet felts become plugged with foreign materials and fail to drain the water being pressed from the formed sheet at a sustained high rate, thereby also resulting in frequent and costly replacement. Dryer felts are basically inefficient because the vaporized water is trapped by the fabric itself resulting in a return tothe sheet of the released water vapor.

It has been recognized that traditional web supporting structures of the papermaking machine, consisting of both machine direction elements or warp yarns and cross direction elements have limited effectiveness in the primary function of water removal. The co-pending U. S. Pat. application Ser. No. 10,412, filed Feb. 11, 1970, now abandoned, is directed to a supporting structure for a paper web or sheet in which the cross direction elements are eliminated and a single endless strand is arranged in a series of machine direction loops or convolutions and serves as a supporting surface to support the web in travel through each of the papermaking sections. The absence of cross machine elements in the supporting surface improves the rate of extraction of water and water vapor as well as reducing wear and facilitating cleaning of the supporting structure,

SUMMARY OF THE INVENTION The present invention is an improvement to the above mentioned patent application and serves to integrate the web supporting surface at a lease area to provide a continuous supporting surface for the web throughout the papermaking machine. More specifically, a strand is mounted to travel in a repeating path over a roll assembly and adjacent machine direction convolutions of the strand are in parallel relation and form a moving supporting surface for the paper web. Similarly, a second strand is mounted to travel in a repeating path over a second roll assembly and adjacent machine direction convolutions of that strand are also in parallel relation and form a second moving supporting surface for the web. According to the invention, the supporting surfaces are integrated by locating the convolutions of one web supporting surface in angular alternating relation with the convolutions of the second web supporting surface at a lease area. The paper web is conveyed from the first web supporting surface across the lease area to the second web supporting surface. By varying the angularity between the first and second web supporting surfaces, it is possible to control the dewatering.characteristics at the lease area, and by utilizing different speeds of travel for the strands in the first and second supporting surfaces, a variety of finish effects can be achieved, ranging from heavy crepeing to dilution or thinning.

As applied to a papermaking machine, the invention provides a continuous supporting surface for the paper web from the time the web is formed at the slice until it leaves the dryer section. As the paper web is supported at all times during forming pressing and drying, any possibility of the web breaking in unsupported areas is eliminated, and thus the speed of travel of the web can be substantially increased, thereby resulting in improved economy in the papermaking operation.

The physical characteristics of the web supporting surface can be varied by utilizing strands of different composition, construction or size. In this manner comingling or integrating of strands of different physical properties can vary the drainage and finish characteristics of the supporting surface as desired.

Other objects and advantages will appear in the course of the following description.

The drawings illustrate the best mode presently contemplated of carrying out the invention.

IN THE DRAWINGS FIG. 1 is a diagrammatic view of a papermaking machine utilizing the web supporting structure of the invention; and

FIG. 2 is a plan view of the structure shown in FIG. 1 with the upper strand and its associated rolls removed.

DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. 1 illustrates diagrammatically a papemaking machine including a Fourdrinier section I, a press section 2, and a dryer section 3. The Fourdrinier section includes a headbox 4 which supplies a slurry of paper pulp through a slice 5 onto a web supporting surface 6 to form a paper web or sheet 7. The supporting surface 6 is formed by a single endless strand 8 which is wound around a roll assembly so that the adjacent machine direction convolutions of the strand are in closely spaced parallel relation and define the moving supporting surface 6.

In forming, a very dilute suspension of fibers is extruded onto the freely draining surface 6 which acts as a filter, collecting the fibers in a wet mat and'permitting free passage of water between the machine direction elements or convolutions. Thus, the forming surface must filter fibers from the suspension and drain away excess amounts of water, while at the same time it supports and transports the web of loose fibers which have built up upon its surface. To do this effectively, the supporting surface 6 should be relatively open with uniform spacing between adjacent convolutions of the strand. Preferably to provide free drainage, the strand is impermeable, and may be formed of metal wire, monofilament plastic, such as nylon, polyester or polyacrylic; or plastic impregnated or non-impregnated textile yarn or braid formed of natural or synthetic fibers or blends of the two.

The roll assembly which supports the strand 8 includes a breast roll 9 located beneath the slice 5, and the slurry, which is discharged through the slice onto the supporting surface 6, is carried over a series of table rolls 10. As the paper web 7 passes over the table rolls 10, a portion of the water in the web is removed and passes through the spaces between the machine direction convolutions of the strand 8.

As the web is further advanced by the moving supporting surface 6 of the endless strand 8, it is subjected to the action of the series of dewatering foils 11 followed by a series of suction boxes 12 which also act to remove a portion of the water from the web. A third sequence of water removal can also be provided by utilizing suction glands which extend the length of the driven couch roll 13. Negative pressure applied to the suction glands serves to further extract water from the web.

The couch roll 13 can be driven in a conventional manner as diagrammatically illustrated in FIG. 2. The drive mechanism includes a motor and transmission unit 14 having its output shaft connected to the shaft of the couch roll 13.

The strand 8 is wound in a repeating pattern around the roll assembly so that the adjacent machine direction convolutions or loops of the strand are in closely spaced parallel relation and define the supporting surface 6. A typical winding pattern is illustrated in FIG. 1. Every other convolution of strand 8, which defines the web supporting surface 6, passes around the couch roll 13 and downwardly to the guide roll 15, around roll 16, and then upwardly to the breast roll 9. The strand then travels from the breast roll 9 to the couch roll 13, where it constitutes a portion of the supporting surface 6, then continues beyond the couch roll 13 to roll 17, then downwardly around roll 18, and upwardly around roll 16 to the breast roll 9, where the pattern is repeated.

It is preferred to mount the strand 8 for endless travel on the roll assembly, and to provide the endless path of travel, the convolution at one side edge of the pattern travels around pulley 19, then horizontally to the opposite side of the machine where it passes around a pulley 20 and reenters the pattern.

The portion of the supporting surface 6 extending between breast roll 9 and couch roll 13 contains a full complement of convolutions and one-half of the group of convolutions are dropped out or eliminated and are returned directly from the couch roll 13 to the roll 15, so that the zone between the couch roll 13 and the roll 17 contains only one-half of the full complement of convolutions of the strand 8.

While it is possible to employ a single strand for the supporting surface in the forming, pressing and drying sections, FIG. 1 illustrates a system in which a separate strand is utilized as the supporting surface in the forming, pressing and drying sections. In the press section 2, a strand 21 is arranged to travel over a roll assembly with the convolutions or loops of the strand travelling in the machine direction being located in closely parallel spaced relation to define a web supporting surface 22 which supports the web 7 and advances the web through the press section to the drying section. The convolutions of the strand 21 in the supporting surface 22 should be contiguous or relatively close together so as to provide maximum uniformity of support and pressure application. The strand should be permeable so as to accommodate water expressed from the paper web, compressible so as to respond to the pressure zone and apply uniform pressure, and resilient so as to recover from the pressure zone and continually provide voids for accepting expressed water. It has been found that textile yarns composed of either natural or synthetic fibers or filaments, or blends, in the form of continuous yarns, or braided or twisted structures, provide these desired characteristics and are particularly satisfactory for use as the strand 21 in the press roll section 2.

In the winding pattern as illustrated in FIG. 1, the strand 21 passes over the

guide roll

23 and 24 and into the nip zone between the press rolls 25 and 26 and the convolutions passing from the roll 23 to the nip zone constitutes a portion of the web supporting surface 22. After leaving the nip zone, the strand passes downwardly around the lower press roll 26, around roll 27 and returns to the roll 24. The strand then passes in a second machine direction convolution from the roll 24 through the nip zone between the press rolls 25 and 26 and continues to the roll 28. After passing around the roll 28, the strand travels around the

rolls

29 and 30 and returns to the roll 23 where the pattern is repeated.

The portion of the supporting surface 22 between the roll 24 and the nip between the

press roll

25 and 26 contains a full complement of the convolutions of the strand 21, while the portion of the supporting surface extending between

rolls

23 and 24 and that extending between the nip zone and the roll 28 contain only onehalf of the full complement of convolutions of strand 21.

According to the invention, the convolutions of strand 8 passing from couch roll 13 to roll 17 are intermingled in alternating sequence with the convolutions of strand 21 travelling from roll 23 to roll 24 at the lease area designed by 31. This results in the web supporting surface 6 and the web supporting surface 22 being located at an obtuse angle, indicated by A in FIG. 1, up to 180 with respect to each other, and preferably in the range of to 179. The paper web 7 is transferred from the web supporting surface 6 across the lease 31 to the web supporting surface 22. The web is advanced through the nip zone by the supporting surface 22, and as the web passes between the coacting press rolls 25 and 26 water is extracted from the web.

By integrating the convolutions of the strands 8 and 21 at the lease area 3] continuous support is provided for the paper web 7 in passing from the forming section 1 to the press roll section 2. As the web 7 is supported at all times during forming and pressing, any possibility of the web breaking in unsupported areas is eliminated. By providing this continuous support, the speed of travel of the paper 7 can be substantially increased thereby resulting in improved economy in the papermaking operation.

The strand 21 is preferably mounted to travel in an endless pattern and to provide the endless pattern the convolution atone side edge of the pattern travels from the guide roll 30 around a pulley 32, then travels horizontally to the opposite side of the machine there it passes upwardly around a second pulley 33 and returns upwardly to the roll 23 where it reenters the pattern.

The strand 21 is driven in the endless path of travel by a conventional drive mechanism which can be associated with one of the press rolls 25. As shown diagrammatically in FIG. 2, the shaft of the press roll 25 is connected to the output shaft of a motor and transmission unit 34.

By varying the speed of travel of the strand 8, as compared to the speed of travel of the strand 21, a variety of effects can be achieved inthe paper sheet 7. For example, if the speed of travel of the strand 8 is considerably faster than that of the strand 21, the fibrous web 7 will tend to pile up at the lease area 31 to provide a bulking or crepeing effect. This accumulation of the stock at the area of the lease 31 provides a more absorbent, bulky-type of product. Conversely, by driving the strand 21 at a faster speedthan the speed of the strand 8, a dilution or thinning out of the web results to thereby provide a thinner paper product. The relative speed of travel between strand 8 and strand 21 can be conveniently varied by utilizing conventional variable speed drive units for one or both of the drive mechanisms l4 and 34.

In addition to varying the speed of travel of the strands 8 and 21, various effects can also be achieved by varying the angularity between the

web supporting surface

6 and 22 as illustrated by the angle A. This change in angularity can be accomplished by repositioningthe various rolls in the roll assemblies, as for example, by raising or lowering the

rolls

17, 23 or both. For example, the roll 17 can be .raised or lowered by means of a bracket 58 which is pivoted to the shaftof roller 18. The upper end of the bracket 58 carries'the shaft for the roll 17. A screw jack 59 is connected to the lower surface of the bracket 58 and through operation of the jack, the. bracket can be raised and lowered to thereby raise or lower the roll 17 and change the angle A, as shown in FIG. 1. By decreasing the angle A, it is possibleto obtain an increase in bulking of the fibrous web and this would also tend to increase the dewatering effect due to the centrifugal action resulting from th change in direction of the the supporting surface. Conversely, increasing angle A will tend to decrease the bulking effect and reduce the dewatering action.

While FIG. 1 illustrates the press rolls 25 and 26 being located a substantial distance from the lease 31, it is contemplated that the press rolls can be positioned at the lease 31 or at any other location where the is a full complement of convolutions.

in the dryer section 3, moisture in the web 7 is driven off by means of heat energy. The dryer section, includes a series of heated upper dryer rolls 35 (only one of which is shown in the drawings) and lower dryer rolls 36 (only two of which are shown in the drawings) and the paper web travels alternately over the

rolls

35 and 36. A strand 37 is arranged to travel in an endless path over a roll assembly in a series of repeating convolutions and adjacent machine direction convolutions serve as a supporting surface 38 for the paper web 7 and apply uniform pressure against the lower dryer rolls 36 to increase the heat transfer from the rolls to the paper web.

in the winding pattern illustrate in FIGv l, the strand 37 passes over the guide rolls 39, 40 and 41 and then travels downwardly beneath the dryer rolls 36 and constitutes a portion of the web supporting surface 38. The

strand 37 then moves upwardly from dryer roll 36 around roll 42 and then downwardly around the second dryer roll 36 to the roll 43, and in traveling from dryer roll 36 to roll 43 the strand also comprises a portion of the web supporting surface 38.

The strand passes downwardly around roll 43, around rolls 44 and 45 and upwardly to roll 40.-The strand 37 then travels in a second machine direction convolution from roll 40 around roll 41, beneath the first dryer roll 36, upwardly around roll 42, beneath the second dryer roll 36 to roll 43. After leaving roll 43, the strand moves beneath rolls 44, 45 and 46 and then travels upwardly to roll 39 where the pattern is repeated. With this winding pattern, the portion of the web supporting surface 38 extending between roll 39 and the roll 40 contains only one-half of the full complement of convolutions of strand 37 while the remaining portion of the supporting surface contains a full complement of convolutions.

The convolutions of strand 21 passing from press rolls 25 and 26 to roll 28 are intermingled, preferably in alternating sequence, with the convolutions of strand 37 passing from roll 39 to roll 40 at a lease, indicated by 47. This results in the web supporting surface 22 and the web supporting surface 38 being located at an obtuse angle, indicated by B in FlG. 1, up to 180 with respect to each other and preferably in the range of 140 to 179. The web 7 is transferred from the surface 22 across the lease 47 to the surface 38 to provide continuous support for the paper web in travelling from the press section 2 to the dryer section 3. The web 7 is then advanced through the dryer section 3 by the supporting surface 38 and the surface 38 acts to press the web firmly against the surface of the heated dryer rolls 36 to increase the rate of moisture removed from the web.

The strand 37 is preferably mounted to travel in an endless path and to provide the endless path the convolution at one side edge of the pattern travels downwardly from roll 43 around pulley 48, then horizontally to the opposite side of the machine where it passes over a second pulley 49 and reenters the pattern.

Strand 37 is driven in its path of travel to advance the paper web '7 by a conventional drive mechanism. As illustrated in FIG. 2, the shaft of one of the dryer rolls 36 is connected to the output shaft of a motor and transmission unit 50.

By varying the speed of travel of strand 37 with respect to strand 21, or by changing the angularity of angle 13, a variety of effects can be achieved in the paper web 7, similar to that previously described with respect to lease area 31.

In addition to strand 37, a second strand 51 is wound over a roll assembly in the dryer section 3 in a series of repeating convolutions, with adjacent machine direction convolutions serving as a supporting surface for web 7 and applying pressure against the upper dryer rolls 35 to increase the heat transfer from the rolls 35 to the paper web.

As shown in FIG. 1, each convolution of strand 51 passes over dryer roll 35 and comprises a portion of the web supporting surface. The strand 51 then travels around rolls 52, 53, 54 and 55 and returns to dryer roll 35 where the pattern is repeated.

While not essential, it is preferred to mount the strand 51 for endless travel, and in this regard the convolution at one side edge of the pattern travels around pulley 56, then horizontally to the opposite side of the machine where it passes upwardly around pulley 57 and then reenters the pattern.

The strand 51 can be driven in its endless path of travel by dryer roll 35 which, in turn, is normally gear connected to the lower dryer rolls 36.

While the drawings show the dryer section 3 to be composed of a series of dryer rolls 35 and 36, other types of drying, such as straight-through drying, infrared drying, or dielectric drying can be substituted.

The invention has particular application to a papermaking machine, but it can also be utilized in other filtering applications where it is desired to convey and extract a fluid from a fluid-impregnated web or substrate.

While FIG. 2 shows the convolutions of

strands

8, 21 and 37 at the supporting

surfaces

6, 22 and 38, to be spaced a considerable distance apart, in practice, these convolutions would be in closely spaced relation and there may be hundreds or thousands of parallel convolutions which compose the web supporting surfaces.

The particular winding patterns of

strand

8, 21, 38 and 51, as illustrated in the drawings, are not critical to the invention and various patterns can be employed. Furthermore, while the above description has shown the convolutions of strands 8 and 21 to be in alternating sequence at the lease 31 and has similarly shown the convolutions of

strands

21 and 37 to be in alternating sequence at lease 47, this winding sequence is not critical to the invention, and it is contemplated that the convolutions of the strands can be integrated in any desired sequence at the lease.

Various modes of carrying out the invention are contemplated as being within the scope of the following claims particularly pointing out and specifically claiming the subject matter which is regarded as the invention.

We claim:

1. A supporting structure for a fluid impregnated web, comprising a first guide roll assembly including a plurality of generally parallel first guide rolls, a first endless strand wound in a repeating pattern on the first guide roll assembly, said pattern including a plurality of closely spaced machine direction convolutions constituting a first web supporting surface adapted to support a fluid-impregnated web, first drive means for driving said first strand in said pattern to thereby advance said web on said first supporting surface, a second guide roll assembly including a plurality of generally parallel second guide rolls, a second endless strand wound in a second repeating pattern on said second guide roll assembly, said second pattern including a plurality of parallel closely spaced machine direction convolutions constituting a second web supporting surface, said second supporting surface being at an obtuse angle with respect to the first supporting surface, and second drive means for driving said second strand in said second pattern, the convolutions of the first web supporting surface being integrated with the convolutions of the second supporting surface at a lease spaced from both said first guide rolls and said second guide rolls, whereby said lease is unsupported, said web being transferred from said first supporting surface across said lease to said second supporting surface.

2. The structure of claim 1, and including means for extracting fluid from the web when it is supported on at least one of said supporting surfaces.

3. The structure of claim 2, wherein said means for extracting fluid includes pressure means for applying pressure to said web to extract fluid therefrom.

4. The structure of claim 3, wherein the pressure means is disposed to apply pressure to the web along a line normal to the direction of movement of the strand.

5. The structure of claim 3, wherein said angle is in the range of l40 to 179.

6. The apparatus of claim 1, and including means for varying said obtuse angle to thereby change the physical characteristics of the web.

7. A supporting structure for a fluid impregnated web, comprising a first guide roll assembly including a plurality of generally parallel first guide rolls, a first endless strand wound in a repeating pattern on the first guide roll assembly, said pattern including a plurality of closely spaced machine direction convolutions constituting a first web supporting surface adapted to support a fluid-impregnated web, first drive means for driving said first strand in said pattern to thereby advance said web on said first supporting surface, a second guide roll assembly including a plurality of generally parallel second guide rolls, a second endless strand wound in a second repeating pattern on said second guide roll assembly, said second pattern including a plurality of parallel closely spaced machine direction convolutions constituting a second web supporting surface, said second supporting surface being at an obtuse angle with respect to the first supporting surface, second drive means for driving said second strand in said second pattern, the convolutions of the first web supporting surface being integrated with the convolutions of the second supporting surface at an unsupported lease location in spaced relation to both said first guide rolls and said second guide rolls, said web being transferred from the first supporting surface across said lease to said second supporting surface, and means for varying the relative speed of travel of said first and second supporting surfaces.

8. A method of papermaking, comprising the steps of supplying a water-impregnated fibrous paper web to a first moving supporting surface, said supporting surface consisting solely of a series of parallel machine direction first elements, said elements comprising convolutions of a first endless strand wound in a repeating pattern, driving said first strand in said pattern to thereby move said web on said first supporting surface, extracing water from the paper web as it is supported on said first supporting surface, intermingling the first elements of said first supporting surface with a series of a parallel machine direction second elements of a second supporting surface at an unsupported lease, said second elements comprising convolutions of a second endless strand wound in a second repeating pattern, driving said second strand in said second pattern, transferring the web from the first supporting surface across the lease to said second supporting surface, and extracting water from the paper web while it is supported on the second supporting surface.

9. The method of claim 8, and including the step of varying the relative speed of travel between said first strand and said second strand to thereby vary the physical characteristics of the paper web.

10. The method of claim 8, and including the step of driving the second strand at a slower speed than the type of paper web.

11. The method of claim 8, and including the step of varying the angularity between the first supporting surface and the second supporting surface to thereby first strand to thereby provide a build-up of the paper 5 change the physical characteristics of the paper web.

Claims

2. The structure of claim 1, and including means for extracting fluid from the web when it is supported on at least one of said supporting surfaces.
3. The structure of claim 2, wherein said means for extracting fluid includes pressure means for applying pressure to said web to extract fluid therefrom.
4. The structure of claim 3, wherein the pressure means is disposed to apply pressure to the web along a line normal to the direction of movement of the strand.
5. The structure of claim 3, wherein said angle is in the range of 140* to 179*.
6. The apparatus of claim 1, and including means for varying said obtuse angle to thereby change the physical characteristics of the web.
7. A supporting structure for a fluid impregnated web, comprising a first guide roll assembly including a plurality of generally parallel first guide rolls, a first endless strand wound in a repeating pattern on the first guide roll assembly, said pattern including a plurality of closely spaced machine direction convolutions constituting a first web supporting surface adapted to support a fluid-impregnated web, first drive means for driving said first strand in said pattern to thereby advance said web on said first supporting surface, a second guide roll assembly including a plurality of generally parallel second guide rolls, a second endless strand wound in a second repeating pattern on said second guide roll assembly, said second pattern including a plurality of parallel closely spaced machine direction convolutions constituting a second web supporting surface, said second supporting surface being at an obtuse angle with respect to the first supporting surface, second drive means for driving said second strand in said second pattern, the convolutions of the first web supporting surface being integrated with the convolutions of the second supporting surface at an unsupported lease location in spaced relation to both said first guide rolls and said second guide rolls, said web being transferred from the first supporting surface across said lease to said second supporting surface, and means for varying the relative speed of travel of said first and second supporting surfaces.
8. A method of papermaking, comprising the steps of supplyiNg a water-impregnated fibrous paper web to a first moving supporting surface, said supporting surface consisting solely of a series of parallel machine direction first elements, said elements comprising convolutions of a first endless strand wound in a repeating pattern, driving said first strand in said pattern to thereby move said web on said first supporting surface, extracing water from the paper web as it is supported on said first supporting surface, intermingling the first elements of said first supporting surface with a series of a parallel machine direction second elements of a second supporting surface at an unsupported lease, said second elements comprising convolutions of a second endless strand wound in a second repeating pattern, driving said second strand in said second pattern, transferring the web from the first supporting surface across the lease to said second supporting surface, and extracting water from the paper web while it is supported on the second supporting surface.
9. The method of claim 8, and including the step of varying the relative speed of travel between said first strand and said second strand to thereby vary the physical characteristics of the paper web.
10. The method of claim 8, and including the step of driving the second strand at a slower speed than the first strand to thereby provide a build-up of the paper web at the lease and provide a more bulky, absorbent-type of paper web.
11. The method of claim 8, and including the step of varying the angularity between the first supporting surface and the second supporting surface to thereby change the physical characteristics of the paper web.