Abstract:
A method of manufacturing a fibrous web in a papermaking machine including the steps of forming, carrying and transferring the fibrous web. The forming step includes forming the fibrous web in a forming device. A first carrying step includes carrying the fibrous web from the forming device through an extended nip press apparatus. A second carrying step includes carrying the fibrous web from the extended nip press apparatus to a transfer point. The transferring step includes transferring the fibrous web at the transfer point to a drying cylinder.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS  
       [0001]     This is a divisional of U.S. patent application Ser. No. 10/768,936, entitled “A DEWATERING APPARATUS IN A PAPER MACHINE”, filed Jan. 30, 2004. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     1. Field of the Invention  
         [0003]     The present invention relates to a paper machine, and, more particularly, to a method and apparatus for removing water from a fibrous web using a dewatering fabric and a permeable press belt in a paper machine that reduces or eliminates mechanical pressing thus increasing sheet quality.  
         [0004]     2. Description of the Related Art  
         [0005]     The Voith Paper patented TissueFlex process substitutes a shoe press for the conventional suction pressure roll in a typical Tissue paper machine. The shoe press provides a wider nip that lowers peak pressure, which has shown an increase in sheet caliper and absorbency. These gains are in the 10% to 20% range depending on furnish and overall load. The suction pressure roll is relocated to a position prior to the nip to dewater the press fabric and sheet prior to reaching the shoe press as disclosed in U.S. Pat. No. 6,235,160.  
         [0006]     The sheet solids going into the shoe press when running a conventional press fabric on a Crescent former fitted with the TissueFlex process is about 23%. Post shoe press solids are in the 37% to 41% range depending on furnish and overall load.  
         [0007]     A fabric is utilized to carry the fiber web during the formation of the web. After the web takes form it is usually subjected to a drying process. The same fabric used during formation of the web or another fabric may come in contact with the web, to move the web across a vacuum section for the remove of moisture from the web. The fabric may additionally absorb moisture from the web and the moisture so absorbed is subsequently removed from the fabric at a later point in the process.  
         [0008]     A problem with conventional fabrics is that they carry too much water and rewetting is one of the major issues relative to light basis weight papers, such as tissue. Further, independent of the vacuum applied the sheet solids remain in the 23% to 25% range.  
         [0009]     What is needed in the art is a more efficient method of removing water from a fibrous web.  
       SUMMARY OF THE INVENTION  
       [0010]     The present invention provides a combination of a dewatering membrane used in conjunction with a permeable belt press in a paper machine.  
         [0011]     The invention comprises, in one form thereof, a dewatering system in a paper machine, the dewatering system including a dewatering fabric and a permeable extended nip press belt. The dewatering fabric includes a woven permeable fabric and a polymeric layer having openings therethrough, the polymeric layer is connected to the permeable fabric. The permeable extended nip press belt applying pressure to a portion of the dewatering fabric.  
         [0012]     An advantage of the present invention is that the combination of the dewatering fabric and the permeable extended nip belt enhance the water removal capacity of the dewatering system.  
         [0013]     Another advantage is that although a significant tension is applied to the extended nip press belt, the pressure per square inch, as applied to the web, is relatively low.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0014]     The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention will be better understood by reference to the following description of embodiments of the invention taken in conjunction with the accompanying drawings, wherein:  
         [0015]      FIG. 1  is a cross-sectional schematic diagram of a paper machine including a dewatering system using at least one of the embodiments of the dewatering fabric and the belt press of the present invention;  
         [0016]      FIG. 2  is a cross-sectional schematic view of an embodiment of a dewatering fabric used in the system of  FIG. 1 ;  
         [0017]      FIG. 3  is a perspective view of yet another embodiment of a dewatering fabric used in the system of  FIG. 1 ;  
         [0018]      FIG. 4  is a sectioned perspective view of yet another embodiment of a dewatering fabric used in the system of  FIG. 1 ;  
         [0019]      FIG. 5  is a sectioned perspective view of still yet another embodiment of a dewatering fabric used in the system of  FIG. 1 ;  
         [0020]      FIG. 6  is a surface view of one side of a permeable belt of the belt press of  FIG. 1 ;  
         [0021]      FIG. 7  is a view of an opposite side of the permeable belt of  FIG. 6 ;  
         [0022]      FIG. 8  is cross-sectional view of the permeable belt of  FIGS. 6 and 7 ;  
         [0023]      FIG. 9  is an enlarged cross-sectional view of the permeable belt of  FIGS. 6-8 ;  
         [0024]      FIG. 10  is a cross-sectional view of the permeable belt of  FIG.7 , taken along A-A of  FIG. 7 ;  
         [0025]      FIG. 11  is another cross-sectional view of the permeable belt of  FIG. 7 , taken along B-B of  FIG. 7 ;  
         [0026]      FIG. 12  is a cross-sectional view of another embodiment of the permeable belt of  FIG. 7 , taken along A-A of  FIG. 7 ;  
         [0027]      FIG. 13  is a cross-sectional view of another embodiment of the permeable belt of  FIG. 7 , taken along B-B of  FIG. 7 ;  
         [0028]      FIG. 14  is a surface view of another embodiment of the permeable belt of the present invention; and  
         [0029]      FIG. 15  is a side view of a portion of the permeable belt of  FIG. 14 .  
         [0030]      FIG. 16  is a cross-sectional schematic diagram of an embodiment of a portion of the paper machine of  FIG. 1 ;  
         [0031]      FIG. 17  is a cross-sectional schematic diagram of another embodiment of a portion of the paper machine of  FIG. 1 ;  
         [0032]      FIG. 18  is a cross-sectional schematic diagram of another embodiment of a portion of the paper machine of  FIG. 1 ;  
         [0033]      FIG. 19  is a cross-sectional schematic diagram of still another embodiment of a portion of the paper machine of  FIG. 1 ;  
         [0034]      FIG. 20A  illustrates an embodiment of the present invention and the moisture content of the fabric and web at various stages; and  
         [0035]      FIG. 20B  illustrates an embodiment of the TissueFlex process and the moisture content of the fabric and web at various stages. 
     
    
       [0036]     Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate one preferred embodiment of the invention, in one form, and such exemplifications are not to be construed as limiting the scope of the invention in any manner.  
       DETAILED DESCRIPTION OF THE INVENTION  
       [0037]     Referring now to the drawings, and more particularly to  FIG. 1 , there is shown a papermaking machine  10 , for the processing of fibrous web  12 . Headbox  11  provides a fibrous slurry to a nip that is formed by a fabric  13  and a dewatering fabric  14 . Moisture is removed through fabric  13  allowing web  12  to form. Web  12  proceeds in machine direction M to dewatering apparatus  15 . Dewatering apparatus  15  includes a suction roll  18 , an optional fabric  20  and a belt press assembly  22 . Belt press assembly  22  includes a fabric  24 , which is also known as a belt  24 . Web  12  proceeds from dewatering apparatus  15  to shoe press  26 , which defines a transfer point with its proximity to Yankee roll  28 . At this transfer point web  12  separates from fabric  14  and attaches to the surface of Yankee roll  28 , which at least partially dries web  12 .  
         [0038]     After forming fibrous web  12  proceeds in machine direction M it comes into contact with fabric  20 . Web  12  then proceeds toward vacuum roll  18  between dewatering fabric  14  and fabric  20 . Fabric  20  is a course mesh fabric. Vacuum roll  18  is operated at a vacuum level to draw moisture from web  12 . Fabric  20 , web  12  and dewatering fabric  14  are pressed against vacuum roll  18  by belt press assembly  22 . A vacuum present in vacuum zone Z pulls a drying fluid, such as air, through permeable belt  24 , then through fabric  20 , then through web  12  and then through dewatering fabric  14 . Moisture collected in vacuum roll  18  is then discharged.  
         [0039]     Now, additionally referring to  FIGS. 2-5 , there are shown several embodiments of dewatering fabric  14  of the present invention. In  FIG. 2 , there is shown fabric  14  having a permeable woven base fabric  50  connected to a batt layer  58 . Fabric  50  includes machine direction yarns  54  and cross-directional yarns  56 . The cross-sectional area of machine direction yarns  54  is larger than the cross-sectional area of cross-direction yarns  56 . Machine direction yarn  54  is a multifilament yarn that may include thousands of fibers. Base fabric  50  is connected to batt layer  58  by a needling process that results in straight through drainage channels therethrough.  
         [0040]     Now, additionally referring to  FIG. 3  there is illustrated another embodiment of dewatering fabric  14 . In this embodiment, base fabric  50  has attached thereto a lattice grid  74  made of a polymer, such as polyurethane, that is put on top of base fabric  50 . The side of dewatering fabric  14  that runs against a roll is illustrated in  FIG. 3 . The opposite side of dewatering fabric  14  (not shown), which is an opposite side of base fabric  50 , is the side that contacts web  12 . Grid  74  may be put on base fabric  50  by utilizing various known procedures, such as, for example, an extrusion technique or a screen-printing technique. As shown in  FIG. 3 , lattice  74  is put on base fabric  50  with an angular orientation relative to machine direction yarns  54  and cross direction yarns  56 . Although this orientation is such that no part of lattice  74  is aligned with machine direction yarns  54  as shown in  FIG. 3 , other orientations such as that shown in  FIG. 4  can also be utilized. Although lattice  74  is shown as a rather uniform grid pattern, this pattern can actually be discontinuous in part. Further, the material between the interconnections of the lattice structure may take a circuitous path rather than being substantially straight, as that shown in  FIG. 3 . Lattice grid  74  is made of a synthetic, such as a polymer or specifically a polyurethane, which attaches itself to base fabric  50  by its natural adhesion properties.  
         [0041]     Lattice grid  74  being a polyurethane has good frictional properties, such that it seats well against the vacuum roll. This then forces vertical airflow and eliminates any x, y plane leakage. The velocity of the air is sufficient to prevent any rewetting once the water makes it through lattice  74   
         [0042]     Additionally, grid  74  may be a thin perforated hydrophobic film  74  having an air permeability of 35 cfm or less, preferably 25 cfm or less having pores therein of approximately 15 microns. Here too we have vertical airflow at high velocity to prevent rewet.  
         [0043]     Now, additionally referring to  FIG. 4 , which illustrates the vacuum roll contacting side of dewatering fabric  14 . This is yet another embodiment of dewatering fabric  14  that includes permeable base fabric  50  having machine direction multifilament yarns  54  and cross-direction monofilament yarns  56 , that are adhered to grid  76 , also known as an anti-rewet layer  76 . Grid  76  is made of a composite material, which may be an elastomeric material the may be the same as that used in lattice grid  74 . Grid  76  includes machine direction yarns  78  and a composite material  80  formed therearound. Grid  76  is a composite structure formed of elastomeric material  80 , and machine direction yarn  78 . Machine direction yarn  78  may be pre-coated with elastomeric material  80  before being placed in rows that are substantially parallel in a mold that is used to reheat elastomeric material  80  causing it to re-flow into the pattern shown as grid  76  in  FIG. 4 . Additional elastomeric material  80  may be put into the mold as well. Grid structure  76 , also known as composite layer  76 , is then connected to base fabric  50  by one of many techniques including laminating grid  76  to permeable fabric  50 , melting elastomeric coated yarn  78  as it is held in position against permeable fabric  50  or by re-melting grid  76  onto base fabric  50 . Additionally, an adhesive may be utilized to attach grid  76  to permeable fabric  50 . Composite layer  76  seals well against the vacuum roll preventing x, y plane leakage and allowing vertical airflow to prevent rewet.  
         [0044]     Now, additionally referring to  FIG. 5 , which illustrates the roll side of dewatering fabric  14 . This structure includes the elements that are shown in  FIG. 4  with the addition of batt fiber  82 . Batt fiber  82  is needled into the structure shown in  FIG. 4  to mechanically bind the two layers together, thereby forming a dewatering fabric  14  having a smooth needled batt fiber surface. Batt material  82  is porous by its nature, additionally the needling process not only connects the layers together, it also creates numerous small porous cavities extending into or completely through the structure of dewatering fabric  14 .  
         [0045]     Dewatering fabric  14  has an air permeability of from 5 to 100 cubic feet/minute preferably 19 cubic feet/minute or higher and more preferably 35 cubic feet/minute or higher. Mean pore diameters, as measured using a Coulter method, are from 5 to 75 microns, preferably 25 microns or higher and more preferably 35 microns or higher. Either surface of dewatering fabric  14  can be treated with a material to make it hydrophobic. Lattice composite layer  76  may be made of a synthetic polymeric material or a polyamide that is laminated to fabric  50 .  
         [0046]     Batt fiber layers are made from fibers ranging from 0.5 d-tex to 22 d-tex and may contain an adhesive to supplement fiber to fiber bonding in each of the layers. The bonding may result, for example, from a low temperature meltable fiber, particles and/or resin. The layers of dewatering fabric  14 , when combined are less than 2.0 millimeters thick, preferably less than 1.50 millimeters, and more preferably less than 1.25 millimeters and even more preferably less than 1.0 millimeter thick.  
         [0047]     Machine direction yarns  54 , shown in  FIGS. 3, 4  and  5 , also known as weft yarns  54  in an endless weaving process, are made of a multi-filament yarn, normally twisted/plied or can be a solid monolithic strand usually of less than 0.40 millimeter diameter, with a preferable diameter of 0.20 millimeter or as low as 0.10 millimeter. Cross direction yarns  56 , shown in  FIGS. 3, 4  and  5 , also known as warp yarns  56  when woven in an endless weaving process are made of a monofilament yarn, of a diameter greater than or equal to 0.2 mm, preferably 0.38 mm. The multifilament yarns are formed in a single strand, twisted cabled or joined side by side to form a flat shaped fabric  50 . Woven permeable fabric  50  may have straight through channels needled through fabric  50 , thereby causing a straight through drainage channel through dewatering fabric  14 . Additionally, a hydrophobic layer may be applied to at least one surface.  
         [0048]     As to the uses of dewatering fabric  14  in papermaking machine  10 , web  12  continues with fabric  14  from its formation until it encounters Yankee roll  28 , where web  12  separates from fabric  14 . At drying apparatus  15  gentle pressure is applied by belt press  22  against web  12  as a mechanical force that helps to accelerate the moisture removal from web  12 . The squeezing action is coupled with a vacuum at zone Z of vacuum roll  18 , to drive moisture from web  12  and through dewatering permeable membrane  14 . Advantageously, moisture is removed through the combination of the pressure applied by the extended nip press contact of belt  24  and the introduction of air through belt  24  and fabrics  14  and  20  enhance the dewatering capability of the present invention.  
         [0049]     Now, additionally referring to  FIGS. 6-9  there are shown details of permeable belt  24  of belt press  22  having holes  36  therethrough, holes  36  are arranged in a hole pattern  38  and grooves  40  are located on one side of belt  24 . Permeable belt  24  is routed so as to engage a surface of dewatering fabric  14  and thereby press dewatering fabric  14  further against web  12 , and web  12  against dewatering fabric  14 , which is supported thereunder by vacuum roll  18 . As this temporary coupling around vacuum roll  18  continues in machine direction M, it encounters a vacuum zone Z causing air to be passed through permeable belt  24 , dewatering fabric  14 , drying web  12  and the moisture picked up by the airflow proceeds further through dewatering fabric  14  and through a porous surface of vacuum roll  18 . There is a low pressing load applied to web  12  over the extended nip as air flows through belt  24 , web  12 , fabric  14  and roll  18 .  
         [0050]     Permeable belt  24 , used in belt press  22 , may be an extended nip press belt made of a flexible reinforced polyurethane. The advantage of a flexible reinforced polyurethane belt is that it provides a low level of pressing in the range of 50-300 KPa and preferably greater than 100 KPa. This allows a suction roll with a 1.2 meter diameter to work in concert with belt  24  having a tension of greater than 30 KN/m and preferably greater than 60 KN/m. The pressing length of permeable belt  24  against dewatering fabric  14 , which is indirectly supported by vacuum roll  18 , is at least as long as suction zone Z in roll  18 . Although the contact portion of permeable belt  24  can be shorter than suction zone Z. Even though significant tension can be applied to belt  24 , since there is a large interface area of belt  24  with roll  18 , the pressure per square centimeter is low so that compression on web  12  is minimized. Further if fabric  14  has a structure associated therewith, significant portions of web  12  will lie in valleys and may not receive any mechanical compression at all.  
         [0051]     Permeable belt  24  has a pattern  38  of holes  36  therethrough, which may, for example, be drilled, laser cut, etched formed or woven therein. Permeable belt  24  may be monoplanar without the grooves shown in  FIGS. 7-9 . In one embodiment of the present invention, the surface having grooves  40  as shown in  FIG. 3  is placed in contact with fabric  20  along a portion of the travel of permeable belt  24  in belt press  22 . Each groove  40  connects with a set of holes  36  to allow the passage and distribution of air in belt  24 . Air is distributed along grooves  40 , which constitutes an open area adjacent to contact areas, where the surface of belt  24  applies pressure against web  12 . Air enters permeable belt  24  through holes  36  and then migrates along grooves  40  passing through fabric  20 , web  12  and dewatering fabric  14 . The diameter of holes  36  is larger than the width of grooves  40 . Although grooves  40  are shown having a generally rectangular cross-sectional, grooves  40  may have a different cross-section contour, such as, triangular, trapezoidal, semi-circular or semi-elliptical. The combination of permeable belt  24 , associated with vacuum roll  18 , is a combination that has been shown to increase sheet solids by at least 15%.  
         [0052]     Permeable belt  24  is capable of running at high running tensions of at least 30 KN/m or 60 KN/m or higher with a relatively high surface contact area of 25% or greater and a high open area of 25% or greater. The composition of permeable belt  24  may include a thin spiral link having a support layer within permeable belt  24 . Alternatively, belt  24  may be a link fabric and fabric  20  may be eliminated, allowing link fabric  24  to both encounter web  12  and to pass drying air therethrough.  
         [0053]     In one embodiment of permeable belt  24 , as illustrated in  FIGS. 10 and 11 , a polyurethane matrix  126  has a permeable structure in the form of a woven structure with reinforcing machine direction yarns  128  and cross direction yarns  130  at least partially embedded within polyurethane matrix  126 .  
         [0054]     In another embodiment of permeable belt  24 , as illustrated in  FIGS. 12 and 13 , a polyurethane matrix  126  has a permeable structure in the form of a spiral link fabric  132  at least partially embedded within polyurethane matrix  126 . Holes  120  extend through belt  24  and may at least partially sever portions of spiral link fabric  132 .  
         [0055]     In yet another embodiment of permeable belt  24 , as illustrated in  FIGS. 14 and 15 , yarns  134  are interlinked by the entwining of generally spiral woven yarns  134  with cross yarns  136  to form link fabric  132 .  
         [0056]     Permeable belt  24  is capable of applying a line force over an extremely long nip, thereby ensuring a long dwell time in which pressure is applied against web  12  as compared to a standard shoe press. There is a simultaneous airflow while web  12  is passing through the long nip. This results in a much lower specific pressure, thereby reducing the sheet compaction and enhancing sheet quality. The present invention further allows for a simultaneous vacuum and pressing dewatering with airflow through the web at the nip itself.  
         [0057]     Advanced dewatering system  15  utilizes belt press  22  to remove water from web  12 , which is formed prior to reaching belt press  22 . Permeable belt  24  is routed in belt press  22  so as to engage a surface of fabric  20  and thereby press fabric  20  further against web  12 , and web  12  against dewatering fabric  14 , which is supported thereunder by vacuum roll  18 . As this coupling of web  12  with fabrics  14  and  20 , and belt  24  continues around vacuum roll  18  in machine direction M, it encounters a vacuum zone Z by which air is drawn through permeable belt  24 , dewatering fabric  14 , drying web  12  and the moisture picked up by the air flow proceeds further through dewatering fabric  14  and through a porous surface of vacuum roll  18 . Drying air passes through holes  36  is distributed along grooves  40  before passing through dewatering fabric  14 . As web  12  leaves belt press  22 , belt  24  and fabric  20  separate from web  12 .  
         [0058]     Web  12  proceeds from dewatering apparatus  15  to transfer device  26  and Yankee  28 . Transfer device  26  may be in the form of a shoe press  26  as illustrated in  FIG. 1 , a suction press roll, a solid press roll or a drilled press roll. Now additionally referring to  FIGS. 16-19 , there are shown alternatives ways in which transfer device  26  may be embodied in which the nip is lengthened. In  FIG. 16 , a roll  27  precedes roll  26 , in machine direction M, and is arranged to cause web  12  to contact Yankee roll  28  prior to roll  26 . In  FIG. 17 , roll  27  precedes roll  26  and roll  29  follows roll  26 , in machine direction M, with roll  29  arranged to cause web  12  to contact Yankee roll  28  at and subsequent to roll  26 . In  FIG. 18 , roll  27  precedes roll  26  and roll  29  follows roll  26 , in machine direction M, with rolls  27  and  29  arranged to cause web  12  to contact Yankee roll  28  prior to and subsequent to roll  26 . In  FIG. 19 , roll  27  precedes roll  26 , in machine direction M, and roll  26  is a shoe press causing web  12  to contact Yankee roll  28 . In each case reduced pressure is used in contacting web  12  with Yankee  28  than in conventional paper machines, because the solids in web  12  are high enough that less pressing is required. This advantageously allows less compaction of web  12  thereby enhancing quality, strength and absorbency of web  12 . A benefit of the present invention is that the caliper and absorbency of the web produced is increased by 25% to 35% over that produced by conventional technology.  
         [0059]     The dewatering that occurs at dewatering apparatus  15  presents a web  12  to Yankee  28  having sheet solids of greater than 30%, preferably greater than 35% and more preferably greater than 40%. This greatly reduces the need for additional mechanical pressing at Yankee  28 .  
         [0060]     The present invention may be applied to other configurations, for example a suction breast roll machine, a twin wire or a Fourdrinier machine. A shoe press may be optionally utilized. If a shoe press is used it will require an additional dewatering apparatus, such as a vacuum turning roll or a multi-slot vacuum box prior to the pressure roll nip at Yankee  28 . The paper web is formed, for example on a Crescent Former between an inner and an outer fabric. The outer fabric can be a conventional or a drainage fabric having differing zonal drainage characteristics. The inner fabric is dewatering fabric  14 . Web  12  is carried by fabric  14  to and around suction roll  18  whereby the dryness of web  12  is increased from about 12% to 23% or higher than 30%. Press apparatus  22  enhances the dewatering effect. The wrapping angle of fabric  14  around roll  18  can be greater or smaller than vacuum zone Z. A pressure is applied by belt  24  to web  12  and fabric  14 . Fabric  20  is optionally present to prevent web  12  from following belt  24 .  
         [0061]     After web  12  passes from dewatering apparatus  15 , web  12  is carried to a press nip between Yankee  28  and shoe press  26 . Shoe press  26  preferably has a shoe width of 80 mm or higher, preferably 120 mm or higher. A maximum peak pressure applied in the length of contact is less that 1.5 MPa, preferably less than 1.0 MPa, and more preferably less than 0.5 MPa. The solids content of web  12  as it enters the Yankee nip is preferably greater than 30%, more preferably greater than 35%, and even more preferably greater than 40%. This eliminates or greatly reduces the need for additional mechanical pressing at the Yankee. With substantially less pressing, the dewatering structures can be less robust than prior art structures an still provide acceptably acceptable service.  
         [0062]     Now, additionally referring to  FIG. 20A  there is shown vacuum roll  18  also known as a suction press roll  18  and a Yankee  28 . Dewatering fabric  14  carries web  12  as water is removed from web  12 . At position A the water content of fabric  14 , also known as felt  14  is 1,200 g/m 2  and the water content of web  12  also known as sheet  12  is 100 g/m 2 . At point C after web  12  is transferred to Yankee  28  the water content of felt  14  is 750 g/m 2  and the water content of sheet  12  is 35 g/m 2 .  
         [0063]     Now, additionally referring to  FIG. 20B  there is shown vacuum roll  18 , shoe press  26  and Yankee  28 . Dewatering fabric  14  carries web  12  as water is removed from web  12 . At position A the water content of fabric  14 , also known as felt  14  is 1,200 g/m 2  and the water content of web  12  also known as sheet  12  is 100 g/m 2 . At point B the water content of felt  14  is 800 g/m 2  and the water content of sheet  12  is 50 g/m 2 . At point C after web  12  is transferred to Yankee  28  the water content of felt  14  is 810 g/m 2  and the water content of sheet  12  is 35 g/m 2 .  
         [0064]     The press fabric strategy for this process as well as other Tissue processes is to provide a fabric  14  for carrying web  12  that is robust enough to withstand repeated compactions in a press nip to thereby provide adequate life of fabric  14 . This has translated into a state of the art press fabric that typically carries around 1,200 g/m 2  of water when saturated. The TissueFlex process, see U.S. Pat. No. 6,235,160, partially illustrated in  FIG. 20B  has separated a suctioning effect from the pressing effect. During the first dewatering process, the press fabric loses up to 400 g/m 2  of water and the sheet loses up to 50 g/m 2  resulting in web  12  having approximately 23% solids. During mechanical pressing in shoe press  26  web  12  will lose another 15 g/m 2 , which is absorbed into the fabric  14 . Comparing this with a standard Crescent former ( FIG. 20A  without TissueFlex, fabric  14  and web  12  simultaneously lose 450 g/m 2  and 65 g/m 2  respectively).  
         [0065]     The ratio of water still in fabric  14  remaining post press is disproportional to the water remaining in web  12 , approximately 20:1 for a conventional Crescent former and for a Crescent former retrofitted to the TissueFlex process. It has been shown that by either reducing residual fabric water in the press fabric or minimizing the rewetting effect with the dewatering fabric of the present invention that sheet solids can increase above 23%, which in turn can yield a dryer sheet after pressing.  
         [0066]     While this invention has been described as having a preferred design, the present invention can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims.