BACKGROUND OF THE INVENTION
1. FIELD OF THE INVENTION
[0001] The present invention relates to the papermaking arts. More specifically, the present
invention relates to papermaker's fabrics, namely the forming, press, dryer fabrics,
and through air dryer (TAD) fabrics, also known as paper machine clothing, on which
paper is manufactured on a paper machine. Also, the invention may be used as a substrate
for a shoe press or transfer or calender belt, any of which can also be used on a
paper machine. In addition, the present invention may be applied in other industrial
settings where industrial belts arc used to dewater a material. Furthermore, the present
invention may be used as a belt and/or sleeve used in the production of nonwovens
by processes such as airlaid, melt blowing, spunbonding, and hydroentangling.
2. DESCRIPTION OF THE PRIOR ART
[0002] During the papermaking process, a cellulosic fibrous web is formed by depositing
a fibrous slurry, that is, an aqueous dispersion of cellulose fibers, on a moving
forming fabric in the forming section a paper machine. A large amount of water is
drained from the slurry through the forming fabric, leaving the cellulosic fibrous
web on the surface of the forming fabric.
[0003] The newly formed cellulosic fibrous web proceeds from the forming section to a press
section, which includes a series of press nips. The cellulosic fibrous web passes
through the press nips supported by a press fabric, or, as is often the case, between
two such press fabrics. In the press nips, the cellulosic fibrous web is subjected
to compressive forces which squeeze water therefrom, and which adhere the cellulose
fibers in the web to one another to turn the cellulosic fibrous web into a paper sheet.
The water is accepted by the press fabric or fabrics and, ideally, does not return
to the paper sheet.
[0004] The paper sheet finally proceeds to a dryer section, which includes at least one
series of rotatable dryer drums or cylinders, which are internally heated by steam.
The newly formed paper sheet is directed in a serpentine path sequentially around
each in the series of drums by a dryer fabric, which holds the paper sheet closely
against the surfaces of the drums. The heated drums reduce the water content of the
paper sheet to a desirable level through evaporation.
[0005] It should be appreciated that the forming, press and dryer fabrics all take the form
of endless loops on the paper machine and function in the manner of conveyors. It
should further be appreciated that paper manufacture is a continuous process which
proceeds at considerable speed. That is to say, the fibrous slurry is continuously
deposited onto the forming fabric in the forming section, while a newly manufactured
paper sheet is continuously wound onto rolls after it exits from the dryer section.
[0006] It should also be appreciated that the vast majority of forming, press and dryer
fabrics are, or at least include as a component, a woven fabric in the form of an
endless loop having a specific length, measured longitudinally therearound, and a
specific width, measured transversely thereacross. Because paper machine configurations
vary widely, paper machine clothing manufacturers are required to produce forming,
press and dryer fabrics to the dimensions required to fit particular positions in
the forming, press and dryer sections of the paper machines of their customers. Needless
to say, this requirement makes it difficult to streamline the manufacturing process,
as each fabric must typically be made to order.
[0007] Moreover, because the surface of a woven fabric is necessarily uneven to some degree,
as knuckles formed where yarns lying in one direction of the fabric wrap around those
lying in another direction lie on the surface, it is difficult to produce a paper
product entirely free of sheet marking.
[0008] The prior art includes several attempts to solve these problems. For example,
U.S. Pat. No. 3,323,226 to Beaumont et al. relates to a synthetic dryer belt comprising one or more plies of polyester film.
Perforations through the belt are formed by mechanical punching.
U.S. Pat. No. 4,495,680 to Beck shows a method and apparatus for forming a base fabric composed solely of warp yarns
to be used in making a papermaker's belt. Essentially, the warp yarns are helically
wound about two parallel rolls. Subsequently, fibrous batting or other nonwoven material
is applied and adhered to the helical array of warp yarns to provide a fillingless
papermaker's belt, which is to say that it has no cross-machine direction yarns.
[0009] U.S. Pat. No. 4,537,658 to Albert shows a papermaker's fabric made from a plurality of elongated, linked, slotted elements.
The elongated elements are linked one to the next either by an integral tongue or
through the use of a pintle connecting means which extends from one elongated element
to the adjacent element. The elongated elements extend in the cross-machine direction
of the disclosed papermaker's fabric, and have flat, parallel top and bottom surfaces.
[0010] U.S. Pat. No. 4,541,895 to Albert describes a papermaker's fabric made up of a plurality of nonwoven sheets laminated
together to define a fabric or belt. The nonwoven sheets are perforated by laser drilling.
Such sheets are composed of unoriented polymer material, and if produced in the fineness
needed for papermaking applications, would lack sufficient dimensional stability to
operate as endless belts on paper machines.
[0011] U.S. Pat. No. 4,842,905 to Stech shows a tessellated papermaker's fabric and elements for making the fabric. The elements
are formed so as to have male or projection members which interlock with female or
recess members. The papermaker's fabric comprises a plurality of the tessellated elements
which have been interconnected to produce a tessellation of a desired length and width.
[0013] WO 2010/068765 discloses an industrial fabric such as an endless belt or sleeve for use in the production
of nonwovens, and a method of making thereof. The industrial fabric is produced by
spirally winding strips of polymeric material, such as an industrial strapping or
ribbon material, and joining the adjoining sides of the strips of material using ultrasonic
welding or laser welding techniques. The fabric may then be perforated using a suitable
technique to make it permeable to air and/or water.
[0014] WO 2010/030570 discloses a support member such as a belt or sleeve which includes a topographical
pattern on its sheet contact side. A plurality of land areas, corresponding depressions,
through voids, and/or groove areas are formed on the top surface of the support member
to produce the topographical pattern. The land areas, corresponding depressions, through
voids, and/or groove areas may be formed by graving, cutting, etching, embossing,
mechanical perforation or a combination thereof. The improved belt or sleeve imparts
desired physical characteristics, such as bulk, appearance, texture, absorbency, strength,
and hand to a nonwoven product produced thereon.
[0015] U.S. Pat. No. 6,630,223 to Hansen shows an industrial belt made from a plurality of spirally wound shaped (non-circular
cross-section) monofilaments which are abutted to each other, side to side of adjacent
turns and secured to one another by a suitable means.
[0016] U.S. Pat. No. 6,989,080 to Hansen shows a nonwoven papermaker's fabric made from a spirally wound MD base layer of
raw stock, overlaid with a CD layer of similar or dissimilar raw stock and mated by
suitable means.
[0018] Fabrics in modern papermaking machines may have a width of from 1.524m to over 10.0584m,
a length of from 12.192m to over 121.92m and weigh from approximately 45.359kg to
over 1360.777kg. These fabrics wear out and require replacement. Replacement of fabrics
often involves taking the machine out of service, removing the worn fabric, setting
up to install a fabric and installing the new fabric. While many fabrics are endless,
many of those used today are on-machine-seamable. Installation of the fabric includes
pulling the fabric body onto a machine and joining the fabric ends to form an endless
belt.
[0019] In response to this need to produce fabrics in a variety of lengths and widths more
quickly and efficiently, fabrics have been produced in recent years using a spiral
winding technique disclosed in commonly assigned
U.S. Pat. No. 5,360,656 to Rexfelt et al. (hereinafter "the '656 patent"). The '656 patent shows a fabric comprising a base
fabric having one or more layers of staple fiber material needled thereinto. The base
fabric comprises at least one layer composed of a spirally wound strip of woven fabric
having a width which is smaller than the width of the base fabric. The base fabric
is endless in the longitudinal, or machine, direction. Lengthwise threads of the spirally
wound strip make an angle with the longitudinal direction of the fabric. The strip
of woven fabric may be flat-woven on a loom which is narrower than those typically
used in the production of paper machine clothing.
SUMMARY OF THE INVENTION
[0020] The present invention provides an alternative solution to the problems addressed
by these prior-art patents/patent applications.
[0021] Accordingly, one embodiment of the present invention is an industrial fabric or belt
for the forming, press and dryer sections, including a through air dryer (TAD), of
a paper machine. The fabric or belt of the present invention may also be used as a
sheet-transfer, long nip press (LNP) or calender belt, or as other industrial process
belts, such as corrugator belts. The fabric may also be used as part of a textile
finishing belt, such as a sanforizing belt or tannery belt, for example. Moreover,
the fabric of the invention may be used in other industrial settings where industrial
belts are used to dewater a material. For example, the fabric may be used in a pulp-forming
or pulp-pressing belt, in a belt used to dewater recycled paper during the deinking
process, such as a dewatering belt on a double-nip-thickener (DNT) deinking machine;
or in a sludge dewatering belt. The inventive fabric may also be used in a belt and/or
sleeve used in the production of nonwovens by processes such as airlaid, spunbonding,
melt blowing or hydroentangling. The belt and/or sleeve is in the form of an endless
loop, and has an inner surface and an outer surface.
[0022] In an exemplary embodiment, the endless belt is formed from strips of material that
are spiral wound around two rolls in a side to side abutting manner. The strips are
firmly attached to each other by a suitable method to form an endless loop at the
required length and width for the particular use. In the case of a sleeve, the strips
may be wound around the surface of a single roll or mandrel which is approximately
the size of the diameter and CD length of the drum on which the sleeve will be used.
The strips of material used are commonly produced as industrial strapping material.
Strapping, especially plastic strapping material, is usually defined as a relatively
thin plastic band used for fastening or clamping objects together. Surprisingly, it
was discovered that this type of plastic material has the appropriate characteristics
to be the material strips to form the inventive belt.
[0023] The difference in definition between (plastic) strapping and monofilament is related
to size, shape and application. Both strapping and monofilament are made by extrusion
processes that have the same basic steps of extrusion, uniaxial orientation and winding.
Monofilament is generally smaller in size than strapping and usually round in shape.
Monofilament is used in a wide variety of applications such as fishing lines and industrial
fabrics, including papermachine clothing. Strapping is generally much larger in size
than monofilament and always basically wider along a major axis, and as such, being
rectangular in shape for its intended purpose.
[0024] It is well known in the art of extrusion that plastic strapping is made by an extrusion
process. It is also well known that this process includes uniaxial orientation of
the extruded material. It is also well known that there are two basic extrusion processes
using uniaxial orientation. One process is the extrusion and orientation of a wide
sheet that is slit into individual straps. The other process is the extrusion of individual
strapping that is oriented. This second process is very much like the process of making
monofilament as evidenced by the similarity in equipment for both processes.
[0025] An advantage of using strapping material versus monofilament is the number of spiral
windings needed to produce a fabric. Monofilaments are usually considered to be yarns
that are no larger than 5 mm in their largest axis. Uniaxial monofilament sizes used
for paper machine clothing and the other uses aforementioned seldom exceed 1.0 mm
in their largest axis. The strapping material used is usually at least 10 mm in width
and sometimes exceeds 100 mm in width. It is envisioned that strapping up to 1000
mm in width could be also used. Suppliers of strapping material which may be used
include companies such as Signode.
[0026] The instant invention provides an improved fabric, belt or sleeve that functions
in place of a traditional belt or sleeve, and imparts desired physical characteristics,
such as bulk, appearance, texture, absorbency, strength, and hand to the paper or
nonwoven product produced thereon.
[0027] Other advantages such as, but not limited to, improved fiber support and release
(no picking) over prior art woven fabrics, and easier cleanability as a result of
no yarn crossovers to trap elementary fibers are provided. If the belt/sleeve has
a surface texture, then more effective patterning/texture is transferred to the paper/nonwoven,
and it also results in better physical properties such as bulk/absorbency.
[0028] Yet another advantage is thickness versus tensile modulus. Polyester (PET) films
in the prior art, for example, have a tensile modulus in the long axis (or machine
direction - MD) of about 3.5 GPa. PET strapping (or ribbon) material has a tensile
modulus ranging from 10 GPa to 12.5 GPa. To achieve the same modulus with a film,
a structure would have to be 3 to 3.6 times thicker.
[0029] The invention therefore, according to one exemplary embodiment, is a fabric, belt
or sleeve formed as a single or multi layer structure from these spiral wound ribbons.
The fabric, belt or sleeve may have planar, smooth top and bottom surfaces. The fabric,
belt or sleeve may also be textured in some manner using any of the means known in
the art, such as for example, sanding, graving, embossing or etching. The belt can
be impermeable to air and/or water. The belt can also be perforated by some mechanical
or thermal (laser) means so it may be permeable to air and/or water.
[0030] In another exemplary embodiment, the ribbon is formed such that is has an interlocking
profile. The belt is formed by spirally winding these interlocking strips and would
have greater integrity than just abutting parallel and/or perpendicular sides of adjacent
ribbon strips. This belt can also be impermeable to air and/or water or perforated
to be made permeable.
[0031] The fabric, belt or sleeve of the present invention may optionally include a functional
coating on one or both of its surfaces. The functional coating may have a top surface
that is planar or smooth, or may alternatively be textured in some manner using any
of the means known in the art, such as for example, sanding, graving, embossing or
etching. The functional coating can be any of the materials known to one of ordinary
skill in the art, such as for example, polyurethane, polyester, polyamide, or any
other polymeric resin material or even rubber, and the functional coating may optionally
include particles such as nano fillers, which can improve resistance to flex fatigue,
crack propagation or wear characteristics of the inventive fabric, belt or sleeve.
[0032] The fabric, belt or sleeve of the present invention may also be used as a reinforcing
base or substrate in a forming fabric, press fabric, dryer fabric, through air dryer
(TAD) fabric, shoe press or transfer or calender belt, a process belt used in airlaid,
melt blowing, spunbonding, or hydroentangling processes, sheet-transfer belt, long
nip press (LNP) or calender belt, corrugator belt, sanforizing belt, tannery belt,
pulp-forming or pulp-pressing belt, dewatering belt on a double-nip-thickener (DNT)
deinking machine, or sludge dewatering belt.
[0033] While the embodiments above are for a single layer of strips of spirally wound ribbon,
there may be advantages to use strips with various geometries that form a belt of
two or more layers. Therefore, according to one exemplary embodiment the belt may
have two or more layers where the strips may be formed such that the two or more layers
mechanically interlock or are attached together by other means known to those skilled
in the art. Again the structure can be either impermeable or perforated to be permeable
to either air and/or water.
[0034] Another exemplary embodiment is a multilayer structure formed using the concept of
a "welding strip" used to further improve the belt integrity. The structure can be
impermeable or perforated to be permeable to either air and/or water.
[0035] While the term fabric and fabric structure is used, fabric, belt, conveyor, sleeve,
support member, and fabric structure are used interchangeably to describe the structures
of the present invention. Similarly, the terms strapping, ribbon, strip of material,
and material strips are used interchangeably throughout the description.
[0036] The various features of novelty which characterize the invention are pointed out
in particularity in the claims annexed to and forming a part of this disclosure. For
a better understanding of the invention, its operating advantages and specific objects
attained by its uses, reference is made to the accompanying descriptive matter in
which preferred, but non-limiting, embodiments of the invention are illustrated in
the accompanying drawings in which corresponding components are identified by the
same reference numerals.
BRIEF DESCRIPTION OF THE DRAWINGS
[0037] The accompanying drawings, which are included to provide a further understanding
of the invention, are incorporated in and constitute a part of this specification.
The drawings presented herein illustrate different embodiments of the invention and
together with the description serve to explain the principles of the invention. In
the drawings:
FIG. 1 is a perspective view of a fabric, belt or sleeve according to one aspect of
the present invention;
FIG. 2 illustrates a method by which the fabric, belt or sleeve of the present invention
may be constructed;
FIGS. 3(a) through 3(i) are cross-sectional views taken in a widthwise direction of
several embodiments of the strip of the material used to manufacture the inventive
fabric, belt or sleeve;
FIGS. 4(a) through 4(d) are cross-sectional views taken in a widthwise direction of
several embodiments of the strip of the material used to manufacture the inventive
fabric, belt or sleeve;
FIGS. 5(a) through 5(c) are cross-sectional views taken in a widthwise direction of
several embodiments of the strip of the material used to manufacture the inventive
fabric, belt or sleeve;
FIGS. 6(a) through 6(d) are cross-sectional views taken in a widthwise direction of
several embodiments of the strip of the material used to manufacture the inventive
fabric, belt or sleeve;
FIGS. 7(a) through 7(d) are cross-sectional views taken in a widthwise direction of
several embodiments of the strip of the material used to manufacture the inventive
fabric, belt or sleeve;
FIGS. 8(a) through 8(c) are cross-sectional views taken in a widthwise direction of
several embodiments of the strip of the material used to manufacture the inventive
fabric, belt or sleeve;
FIG. 9 is a bar graph depicting the advantages of using a uniaxially oriented material
(strap/ribbon) over a biaxially oriented material (film) and an extruded material
(molded part);
FIGS. 10(a) through 10(d) illustrate steps involved in a method by which the fabric,
belt or sleeve of the present invention may be constructed;
FIGS. 11(a) and 11(b) are schematics of an apparatus that may be used in forming the
fabric, belt or sleeve according to one aspect of the present invention;
FIG. 12 is a schematic of an apparatus that may be used in forming the fabric, belt
or sleeve according to one aspect of the present invention;
FIG. 13 is a cross-sectional view of a fabric, belt or sleeve according to one aspect
of the present invention; and
FIG. 14 is an apparatus used in the manufacture of a fabric, belt or sleeve according
to one aspect of the present invention.
DETAILED DESCRIPTION OF THE PREFERED EMBODIMENTS
[0038] Now turning to the figures, FIG. 1 is a perspective view of the industrial fabric,
belt or sleeve 10 of the present invention. The fabric, belt or sleeve 10 has an inner
surface 12 and an outer surface 14, and is fashioned by spirally winding a strip of
polymeric material 16, for example an industrial strapping material, in a plurality
of abutting and mutually adjoined turns. The strip of material 16 spirals in a substantially
longitudinal direction around the length of the fabric 10 by virtue of the helical
fashion in which the fabric, belt or sleeve 10 is constructed.
[0039] An exemplary method by which the fabric, belt or sleeve 10 may be manufactured is
illustrated in FIG. 2. Apparatus 20 includes a first process roll 22 and a second
process roll 24, each of which is rotatable around its longitudinal axis. The first
process roll 22 and the second process roll 24 are parallel to one another, and are
separated by a distance which determines the overall length of the fabric, belt or
sleeve 10 to be manufactured thereon, as measured longitudinally therearound. At the
side of the first process roll 22, there is provided a supply reel (not shown in the
figures) rotatably mounted about an axis and displaceable parallel to process rolls
22 and 24. The supply reel accommodates a reeled supply of the strip of material 16
having a width of 10 mm or more, for example. The supply reel is initially positioned
at the lefthand end of the first process roll 22, for example, before being continuously
displaced to the right or other side at a predetermined speed.
[0040] To begin the manufacture of the fabric, belt or sleeve 10, the beginning of the strip
of polymeric strapping material 16 is extended in taut condition from the first process
roll 22 toward the second process roll 24, around the second process roll 24, and
back to the first process roll 22 forming a first coil of a closed helix 26. To close
the first coil of the closed helix 26, the beginning of the strip of material 16 is
joined to the end of the first coil thereof at point 28. As will be discussed below,
adjacent turns of the spirally wound strip of material 16 are joined to one another
by mechanical and/or adhesive means.
[0041] Therefore, subsequent coils of closed helix 26 are produced by rotating first process
roll 22 and second process roll 24 in a common direction as indicated by the arrows
in FIG. 2, while feeding the strip of material 16 onto the first process roll 22.
At the same time, the strip of material 16 being freshly wound onto the first process
roll 22 is continuously joined to that already on the first process roll 22 and the
second process roll 24 by, for example, mechanical and/or adhesive or any other suitable
means to produce additional coils of closed helix 26.
[0042] This process continues until the closed helix 26 has a desired width, as measured
axially along the first process roll 22 or the second process roll 24. At that point,
the strip of material 16 not yet wound onto the first process roll 22 and the second
process roll 24 is cut, and the closed helix 26 produced therefrom is removed from
the first process roll 22 and the second process roll 24 to provide the fabric, belt
or sleeve 10 of the present invention.
[0043] Although a two roll set up is described herein, it may be apparent to one of ordinary
skill in the art that the strips may be wound around the surface of a single roll
or mandrel to form the instant fabric, belt or sleeve. A roll or mandrel of appropriate
size may be selected based on the desired dimension of the fabric, belt or sleeve
to be produced.
[0044] The present method for producing fabric, belt or sleeve 10 is quite versatile and
adaptable to the production of papermaker's and/or industrial fabrics or belts of
a variety of longitudinal and transverse dimensions. That is to say, the manufacturer,
by practicing the present invention, need no longer produce a woven fabric of appropriate
length and width for a given paper machine. Rather, the manufacturer need only separate
the first process roll 22 and the second process roll 24 by the appropriate distance,
to determine the approximate length of the fabric, belt or sleeve 10, and wind the
strip of material 16 onto the first process roll 22 and the second process roll 24
until the closed helix 26 has reached the approximate desired width.
[0045] Further, because the fabric, belt or sleeve 10 is produced by spirally winding a
strip of polymeric strapping material 16, and is not a woven fabric, the outer surface
12 of the fabric, belt or sleeve 10 is smooth and continuous, and lacks the knuckles
which prevent the surfaces of a woven fabric from being perfectly smooth. The fabrics,
belts, or sleeves of the present invention may, however, have geometrical characteristics
that provide enhanced topography and bulk to the paper or nonwoven product produced
thereon. Other advantages of the instant support members include easier sheet or web
release, improved contamination resistance, and reduced fiber picking. Yet another
advantage is that it avoids the constraints of and need for a conventional weaving
loom since the through voids can be placed in any desired location or pattern. The
fabric, belt or sleeve may also have a texture on one or both surfaces, produced using
any of the means known in the art, such as for example, sanding, graving, embossing
or etching. Alternatively, the fabric, belt or sleeve may be smooth on one or both
surfaces. FIGS. 3(a) through 3(i) are cross-sectional views, taken in a widthwise
direction, of several embodiments of the strip of material used to produce the present
fabric, belt or sleeve. Each embodiment includes upper and lower surfaces which may
be flat (planar) and parallel to one another, or may have a certain profile intended
to suit a particular application. Turning to FIG. 3(a), material strip 16 has an upper
surface 15, a lower surface 17, a first planar side 18 and a second planar side 19,
according to one embodiment of the invention. The upper surface 15 and the lower surface
17 may be flat (planar) and parallel to one another, and the first planar side 18
and the second planar side 19 may be slanted in parallel directions, so that the first
planar side 18 of each spirally wound strip of material 16 abuts closely against the
second planar side 19 of the immediately preceding turn thereof. Each turn of the
strip of material 16 is joined to its adjacent turns by joining their respective first
and second planar sides 18, 19 to one another by an adhesive, for example, which may
be a heat-activated, room-temperature-cured (RTC) or hot-melt adhesive, for example,
or any other suitable means.
[0046] In FIG. 3(b), material strip 16 may have a cross-sectional structure that enables
a mechanical interlock for joining adjacent strips of material 16 in the spirally
formed fabric, belt or sleeve. Adjacent strips of material 16 can be the same or different
in size and/or profile, but each has a locking position, as shown in FIG. 3(b). Other
examples of mechanical interlock structures are shown in FIGS. 3(c) through 3(g) where
the cross section of individual strips of material 16 is illustrated. In each case,
one side of the strip of material 16 may be designed to mechanically interlock or
connect with the other side of the adjacent strip of material 16. For example, referring
to the embodiment shown in FIG. 3(g), the strip of material 16 may have an upper surface
42, a lower surface 44, a tongue 46 on one side and a corresponding groove 48 on the
other side. The tongue 46 may have dimensions corresponding to those of the groove
48, so that the tongue 46 on each spirally wound turn of strip 16 fits into the groove
48 of the immediately preceding turn thereof. Each turn of the strip of material 16
is joined to its adjacent turns by securing tongues 46 in the grooves 48. The upper
surface 42 and the lower surface 44 may be flat (planar) and parallel to one another,
or non-planar and non-parallel depending on the application, or even may be convexly
or concavely rounded in the widthwise direction thereof, as shown in FIG. 3(f). Similarly,
either side of the strip may be cylindrically convex or concave shaped with the same
radius of curvature. FIG. 3(h) shows another embodiment of the present invention.
[0047] In addition to having an extruded strip of material with opposing hemispheres or
profiles as described above, various other shapes could be extruded or machined from
rectangular extrusions to have mating edges with raised rails, which may facilitate
bonding by mechanical and/or adhesive means. One such structure, according to one
exemplary embodiment of the invention is shown in FIG. 3(i). Alternatively, the material
strip may not require a right and left side that mate or join together. For example,
as shown in FIG. 4(a), the cross section of strip of material 16 may have interlocking
grooves on its upper surface or top side, or material strip 16 may have interlocking
grooves on its lower surface or bottom side, as shown in FIG. 4(b).
[0048] FIG. 4(c), for example, shows the material strips of FIGS. 4(a) and 4(b) positioned
for interlocking. The arrows in FIG. 4(c) indicate, for example, the direction that
each of the material strips 16 would have to be moved in order to engage the grooves
and interlock the two strips. FIG. 4(d) shows the two material strips 16 after they
have been interlocked or joined together. Although only two of the mating material
strips are shown in the exemplary embodiments, it should be noted that the final fabric,
belt or sleeve is formed of several of the material strips interlocked together. Clearly,
if one interlocks the material strips in a spiral winding process, one can form a
sheet of material in the form of an endless loop. It should also be noted that while
mechanical interlocks are shown, the strength of the interlocks can be improved by,
for example, thermal bonding, especially by a technique known as selective bonding
as exemplified by a commercial process known as 'Clearweld.' (See www.clearweld.com).
[0049] FIG. 5(a) shows a cross-sectional view of a material strip 16 that has grooves both
on the top side and bottom side thereof. FIG. 5(b) shows how two material strips 16
having the cross-sectional shape shown in FIG. 5(a) can be interlocked. The interlocked
structure results in grooves on the top and bottom surface of the end product.
[0050] Referring to the embodiment shown in FIG. 5(c), FIG. 5(c) shows the interlocking
of the two material strips 16 shown in FIG. 5(a) and FIG. 4(b). This results in a
sheet product that has grooves on the bottom surface with a flat top surface. Likewise,
one may also form a structure having grooves on the top surface with a flat bottom
surface.
[0051] Another exemplary embodiment is a fabric, belt or sleeve formed from material strips
16 that have knob-like interlocks or "positive" locks that form stronger interlocks
due to their mechanical design. The designs have "positive" interlocks in the sense
that the pins and the receptors for the pins have mechanical interference that require
considerable force either to join the ribbons together or to separate them. FIG. 6(a),
for example, illustrates the features of knoblike interlocks in individual ribbon-like
material strips 16. FIG. 6(b) illustrates the features of knoblike interlocks in individual
ribbon-like material strips 16 of opposite configuration that are designed to interlock
with the structure shown in FIG. 6(a). FIG. 6(c) shows the individual ribbon-like
material strips of FIGS. 6(a) and 6(b) positioned for interlocking. It is to be noted
here that the staggered position of the top and bottom ribbons is in order to accommodate
another material strip 16 of opposite configuration. Finally, FIG. 6(d) illustrates
these same strips after they have been pressed together to form an interlocked structure.
Several ribbon-like material strips like these may be interlocked together to form
the final fabric, belt or sleeve.
[0052] Another exemplary embodiment is a fabric, belt or sleeve formed from material strips
16 that have grooves on both the top and bottom sides thereof, for example, as shown
in FIG. 7(a). These two ribbon-like material strips 16 are designed to be joined together
to form a positive interlock, as shown in FIG. 7(b). It is to be noted that the top
and bottom surfaces both retain grooves in their respective surfaces. Also, looking
at FIGS. 7(a) and 7(b) it may be apparent to one of ordinary skill in the art to combine
three or more strips to make a multi-layered structure, or if just two strips are
used, the groove profile of the grooves in the top strip may be the same or different
on top versus bottom sides. Similarly, the groove profile of the grooves in the bottom
strip may be the same or different on either sides. As noted earlier, while the embodiments
described herein are for a single layer of spirally wound ribbons or strips, there
may be advantages to use strips with various geometries that form a belt of two or
more layers. Therefore, according to one exemplary embodiment the belt may have two
or more layers where the strips may be formed such that the two or more layers mechanically
interlock. Each layer may be spirally wound in an opposite direction or angled in
the MD to provide additional strength.
[0053] FIG. 7(c) shows an interlocked structure that results in a grooved bottom surface
and a flat top surface, whereas FIG. 7(d) shows an interlocked structure that results
in a flat bottom surface and a grooved top surface, for example.
[0054] As it may be obvious to one of ordinary skill in the art, many shapes may be considered
for making positive interlocks as described above. For example, the previous few embodiments
focused on round knob-like protrusions and round receptacles. However, it is also
possible to use other shapes such as a trapezoid to accomplish the same effect. An
example of a positive interlock having such a shape is shown in FIG. 8(a). Alternatively,
one can mix shapes to accomplish a positive interlock. An example of mixed shapes
is shown in FIGS. 8(b) and 8(c).
[0055] The mechanical interlock thus formed between adjacent strips of material as described
in the above embodiments increases the ease with which a spiral wound base fabric
or structure can be made, because without such a lock, it is possible for adjacent
strips of material to wander and separate during the process of making the spirally
wound fabric. By mechanically interlocking adjacent spirals, one may prevent wandering
and separation between adjacent spirals. Additionally, one may not need to depend
solely on the strength of the mechanical lock for joining strength as one may also
form thermal welds in the mechanically locked zones of the fabric. According to one
embodiment of the invention, this can be accomplished by placing a near infrared or
infrared or laser absorbing dye prior to locking the male/female components together
followed by exposing the mechanical lock to a near infrared or infrared energy or
laser source that causes thermal welding of the mechanical lock without melting material
external to the zone of the mechanical lock.
[0056] The strip of material described in the above embodiments may be extruded from any
polymeric resin material known to those of ordinary skill in the art, such as for
example, polyester, polyamide, polyurethane, polypropylene, polyether ether ketone
resins, etc. Industrial strapping is attractive as a base material, given that it
is uniaxally oriented, i.e., it has at least twice the tensile modulus of a biaxially
oriented material (film) and up to ten times the modulus of an extruded material (molded).
That is to say, the structure resulting from a uniaxially oriented material requires
less than half the thickness of biaxially oriented material (film) and less than one-tenth
the thickness of an extruded material (molded). This feature is illustrated in FIG.
9 where results are shown for designing a part that has been designed for a specific
force and strain for width. The equation used in this design problem is the relationship
between stress and strain shown as follows:

[0057] The force (or load) is kept constant along with the width and strain in this illustration.
The equation shows that the required thickness is inversely proportional to the modulus
of the material. This equation is representative of the problem of designing paper
machine clothing for dimensional stability, i.e., the load is known, the maximum strain
is known and the width of the machine is fixed. The result is shown in terms of the
final thickness of the part required depending upon the modulus of the material employed.
Clearly, uniaxial materials such as strappings or ribbons have a significant advantage
over films and molded polymers as shown by FIG. 9. The instant fabrics, belts or sleeves,
however, are not limited to uniaxial or biaxial orientation of the strapping, in that
either or both orientations may be used in the practice of the instant invention.
The strip of material or strapping material described in the above embodiments includes
a reinforcing material to improve the mechanical strength of the overall structure.
The reinforcing material may be fibers, yarns, monofilaments or multifilament yarns
oriented in the MD of the fabric, sleeve or belt, along the length of the strapping
material. The reinforcing material may be included through an extrusion or pultrusion
process where the fibers or yarns may be extruded or pultruded along with the material
forming the strip of material or strapping material. They may be fully embedded within
the material of the strapping or they may be partially embedded onto one or both surfaces
of the strapping material, or both. Reinforcing fibers or yarns may be formed of a
high-modulus material, such as for example, aramids, including but not limited to
Kevlar
® and Nomex
®, and may provide extra strength, tensile modulus, tear and/or crack resistance, resistance
to abrasion and/or chemical degradation to the strip of material or strapping material.
Broadly, the reinforcing fibers or yarns may be made from thermoplastic and/or thermosetting
polymers. Non-limiting examples of suitable fiber materials include glass, carbon,
polyester, and polyethylene. The melting temperature of said reinforcing fibers or
yarns is higher than the melting temperature of said strip of material or strapping
material. Strapping is usually supplied in continuous lengths with the product having
a rectangular cross section. It is a tough, general purpose, usually untreated polyester
strip with excellent handling characteristics, which makes it suitable for many industrial
applications. It has excellent mechanical strength and dimensional stability as noted
earlier, and does not become brittle with age under normal conditions. Strapping has
good resistance to moisture and most chemicals, and can withstand temperatures of
-70 degrees C to 150 degrees C or more. Typical cross-sectional dimensions of a strapping
material that may be used in the present invention are, for example, 0.30mm (or more)
thickness and 10mm (or more) width. While strapping can be spirally wound, the adjacent
wraps of strapping that do not have any means of interlocking to be held together
may need to welded or joined in some manner. In such cases, laser welding or ultrasonic
welding may be used in to fix or weld the adjacent ribbons or material strips together
so as to improve cross-machine direction ("CD") properties, such as strength, and
reducing the risk of separation of neighboring material strips.
[0058] While uniaxial strapping is found to have the maximum MD modulus, properties other
than modulus may also be important. For example, if the MD modulus is too high for
the strapping material, then crack and flex fatigue resistance of the final structure
may be unacceptable. Alternatively, CD properties of the final structure may also
be important. For instance, when referring to PET material and material strips of
the same thickness, non-oriented strips may have a typical MD modulus of about 3GPa
and strength of about 50MPa. On the other hand, a biaxially oriented strip may have
a MD modulus of about 4.7GPa and strength of about 170MPa. It is found that modifying
the processing of a uniaxial strip such that the MD modulus may be between 6-10GPa
and strength may be equal to or greater than 250MPa, may result in a strip with CD
strength approaching, approximately, 100MPa. Further the material may be less brittle,
i.e. it may not crack when repeatedly flexed, and may process better when joining
the strips together. The bond between the strips may also resist separation during
the intended use on the production machine.
[0059] One method to hold together the adjacent strips, according to one embodiment of the
invention, is to ultrasonically weld adjacent strips edge to edge while simultaneously
providing a sideways pressure to keep the edges in contact with each other. For example,
one part of the welding device can hold one strip, preferably the strip that has already
been wound into a spiral, down against a supporting roll while another part of the
device pushes the other strip, preferably the strip being unwound, up against the
strip being held down. This edge to edge welding is illustrated in FIG. 11(a), for
example.
[0060] The application of ultrasonic gap welding results in a particularly strong bond.
By contrast, ultrasonic welding in either a time mode or energy mode, which is also
known as conventional ultrasonic welding, results in a bond that can be described
as brittle. Therefore, it may be concluded that a bond formed via ultrasonic gap welding
is preferred versus conventional ultrasonic welding.
[0061] Another exemplary method to hold together adjacent strips, according to one embodiment
of the invention, is to apply an adhesive 30 to ends 34, 36 of adjacent strips 16,
16, and joining them is shown in FIGS. 10(a) -10(d). It is to be noted that a filler
material 32, may be used to fill gaps or portions where the strips do not contact
each other.
[0062] Another method to hold together adjacent strips of material or functional strips,
according to one embodiment of the invention, is to use a "welding strip" comprised
of the same basic material as the strip of material. For example, this welding strip
is shown in FIG. 11(b) as a thin material appearing above and below the strips of
material. In such an arrangement, the welding strip provides a material for the strips
of material to be welded such that the assembled structure does not depend upon the
edge to edge welding depicted in FIG. 11(a). Using the welding strip method, edge
to edge welding may result; however, it is neither required nor preferred. Using the
welding strip method, a "sandwich" or laminate type of structure may be formed with
the horizontal surface of the strip of material being welded to the horizontal surface
of the welding strip, as shown in FIG. 11(b). It is to be noted here that the welding
strip does not have to be located both above and below the strips of material, in
that the welding strip may be located either just above or just below the strips of
material. According to one aspect, the welding strip may also be the central part
of the sandwiched structure with the strip of material being above and/or below the
welding strip. Additionally, the welding strip is shown as being thinner than the
strip of material and as being the same width as the strip of material merely for
exemplary purposes. The welding strip may well be narrower or broader than the strip
of material, and may be of the same thickness or even thicker than the strip of material.
The welding strip may also be another piece of strip of material rather than being
a special material made solely for the purpose of the welding strip. The welding strip
may also have adhesive applied to one of its surfaces to assist in holding the welding
strip in place for the welding operation. However, if such an adhesive is used, it
is preferred that the adhesive be partially applied to the welding strip versus the
entire surface, because partial application may promote a strong weld between like
materials (polyester to polyester, for example) of the strip of material and the welding
strip upon ultrasonic or laser welding.
[0063] If the welding strip is made from an extruded polymer with no orientation, then it
is preferred that the welding strip be much thinner than the strip of material, because
a non-oriented extruded welding strip is less capable of maintaining the dimensional
stability of the final structure as illustrated earlier in this disclosure. However,
if the welding strip is made from an oriented polymer, it is preferred that the welding
strip in combination with the strip of material be as thin as possible. As noted earlier,
the welding strip may be another piece of strip of material. However, if this is the
case, it is preferred that the thickness of the individual materials be selected such
that the total thickness of the sandwich or laminate can be minimized. As also noted
earlier, the welding strip may be coated with an adhesive that is used to hold the
structure together for further processing. According to one aspect, the welding strip
with adhesive may be used, for example, to create a structure that goes directly to
a perforation step, which could be laser drilling without any ultrasonic bonding such
that the laser drilling or laser perforation produces spot welds that can hold the
sandwich structure together.
[0064] Another method to hold together adjacent strips of material, according to one embodiment
of the invention, is to weld the adjacent strips using a laser welding technique.
[0065] FIG. 14 illustrates an exemplary apparatus 320 that may be used in the laser welding
process, according to one aspect of the invention. In this process, fabric, belt or
sleeve 322 as shown in FIG. 14 should be understood to be a relatively short portion
of the entire length of the final fabric, belt or sleeve. While the fabric, belt or
sleeve 322 may be endless, it may most practically be mounted about a pair of rolls,
not illustrated in the figure, but known to those of ordinary skill in the art. In
such an arrangement, apparatus 320 may be disposed on one of the two surfaces, most
conveniently the top surface, of the fabric 322 between the two rolls. Whether endless
or not, fabric 322 may preferably be placed under an appropriate degree of tension
during the process. Moreover, to prevent sagging, fabric 322 may be supported from
below by a horizontal support member as it moves through apparatus 320.
[0066] Referring now more specifically to FIG. 14, where fabric 322 is indicated as moving
in an upward direction through the apparatus 320 as the method of the present invention
is being practiced. The laser heads that are used in the welding process may traverse
across the fabric in a CD or widthwise "X" direction while the fabric may move in
the MD or "Y" direction. It may also be possible to setup a system where the fabric
is moved in three-dimensions relative to a mechanically fixed laser welding head.
[0067] The advantage of laser welding over ultrasonic welding is that laser welding can
be accomplished at speeds in the range of 100 meters per minute while ultrasonic welding
has a top end speed of about 10 meters per minute. The addition of a light absorptive
dye or ink absorber to the edges of the strips may also assist in concentrating the
thermal effect of the laser. Absorbers could be black ink or near IR dyes that are
not visible to the human eye, such as for example those utilized by "Clearweld." (See
www.clearweld.com)
[0068] Once the final fabric, belt or sleeve is made and adjacent strips in the fabric,
belt or sleeve have been welded or joined in some manner, holes or through voids allowing
fluids (air and/or water) to pass from one side of the fabric to the other side of
the fabric can be provided by means such as laser drilling. It should be noted that
these through holes or through voids that allow fluid to pass from one side of the
fabric to the other can be made either before or after the spiral winding and joining
process. Such holes or through voids can be made via laser drilling or any other suitable
hole/perforation making process, for example, using a mechanical or thermal means,
and can be of any size, shape, orientation, form and/or pattern, depending on the
intended use. The through voids or holes can have a nominal diameter in the range
of 0.0127cm to 0.0254cm or more. An exemplary embodiment is shown in FIG. 13, which
is a cross section, taken in a transverse, or cross-machine, direction, of a fabric
80 of the present invention, strips of material 82 are provided along their entire
lengths with a plurality of holes 84 for the passage of air and/or water.
[0069] The inventive fabric, as noted earlier, may be used as a substrate for use in a forming
fabric, press fabric, dryer fabric, through air dryer (TAD) fabric, shoe press or
transfer or calender belt, or a process belt used in airlaid, melt blowing, spunbonding,
or hydroentangling processes. The inventive fabric, belt or sleeve may include one
or more additional layers, for example textile layers, on top of or under the substrate
formed using the strips of material, merely to provide functionality, and not reinforcement.
For example, a MD yarn array may be laminated to the backside of the belt or sleeve
to create void spaces. Alternatively, the one or more layers may be provided in between
two layers of strapping. The additional layers used may be any of woven or nonwoven
materials, MD or CD yarn arrays, spirally wound strips of woven material that have
a width less than the width of the fabric, fibrous webs, films, or a combination thereof,
and may be attached to the substrate using any suitable technique known to one of
ordinary skill in the art. Needle punching, thermal bonding and chemical bonding are
but few examples.
[0070] As noted earlier, the industrial fabric, belt or sleeve of the invention may be used
in the forming, press and dryer sections, including a through air dryer (TAD), of
a paper machine. The fabric, belt or sleeve may also be used as a sheet-transfer,
long nip press (LNP) or calender belt, or as other industrial process belts, such
as corrugator belts. The inventive fabric, belt or sleeve may have a texture on one
or both surfaces, which can be produced using any of the means known in the art, such
as for example, sanding, graving, embossing or etching. The fabric may also be used
as part of a textile finishing belt, such as a sanforizing belt or tannery belt, for
example. Moreover, the fabric, belt or sleeve of the invention may be used in other
industrial settings where industrial belts are used to dewater a material. For example,
the fabric, belt or sleeve may be used in a pulp-forming or pulp-pressing belt, in
a belt used to dewater recycled paper during the deinking process, such as a dewatering
belt on a double-nip-thickener (DNT) deinking machine; or in a sludge dewatering belt.
The inventive fabric, belt or sleeve may also be used as a belt used in the production
of nonwovens by processes such as airlaid, spunbonding, melt blowing or hydroentangling.
[0071] According to one exemplary embodiment, the fabric, belt or sleeve of the present
invention may optionally include a functional coating on one or both of its surfaces.
The functional coating may have a top surface that is planar or smooth, or may alternatively
be textured in some manner using any of the means known in the art, such as for example,
sanding, graving, embossing or etching. The functional coating can be any of the materials
known to one of ordinary skill in the art, such as for example, polyurethane, polyester,
polyamide, or any other polymeric resin material or even rubber, and the functional
coating may optionally include particles such as nano fillers, which can improve resistance
to flex fatigue, crack propagation or wear characteristics of the inventive fabric,
belt or sleeve.
[0072] The fabric, belt or sleeve of the present invention may also be used as a reinforcing
base or substrate in a forming fabric, press fabric, dryer fabric, through air dryer
(TAD) fabric, shoe press or transfer or calender belt, a process belt used in airlaid,
melt blowing, spunbonding, or hydroentangling processes, sheet-transfer belt, long
nip press (LNP) or calender belt, corrugator belt, sanforizing belt, tannery belt,
pulp-forming or pulp-pressing belt, dewatering belt on a double-nip-thickener (DNT)
deinking machine, or sludge dewatering belt. The reinforcing base or substrate can
have a smooth planar surface or it can be textured. The reinforcing base or substrate
can optionally include a functional coating on one or both of its surfaces, which
in turn can have a smooth planar surface or may be textured.
[0073] Although preferred embodiments of the present invention and modifications thereof
have been described in detail herein, it is to be understood that the invention is
not limited to these precise embodiments and modifications, and that other modifications
and variations may be effected by one skilled in the art without departing from the
scope of the invention as defined by the appended claims.
1. An endless industrial fabric, belt or sleeve (10) comprising:
one or more spirally wound strips of polymeric material (16) wherein said one or more
strips of polymeric material is an industrial strapping or ribbon material,
wherein the strapping or ribbon material is uniaxially oriented and has at least twice
the tensile modulus of a biaxially oriented material and up to ten times the modulus
of an extruded material,
characterised in that said industrial strapping or ribbon material includes a reinforcing material oriented
in the MD of the belt or sleeve selected from the group consisting of fibers, yarns,
monofilaments and multifilament yarns,
wherein the reinforcing material is made of a material selected from the group consisting
of aramids, thermoplastic polymers, thermosetting polymers, glass, and carbon,
and wherein the melting temperature of the strapping or ribbon material is lower than
the melting temperature of the reinforcing material.
2. The fabric, belt or sleeve according to claim 1, wherein said fabric, belt or sleeve
is a substrate for use in a forming fabric, press fabric, dryer fabric, through air
dryer (TAD) fabric, shoe press or transfer or calender belt, a process belt used in
airlaid melt blowing, spunbonding, or hydroentangling processes, sheet-transfer belt,
long nip press (LNP) or calender belt, corrugator belt, sanforizing belt, tannery
belt, pulp-forming or pulp-pressing belt, dewatering belt on a double-nip-thickener
(DNT) deinking machine, or sludge dewatering belt.
3. The fabric, belt or sleeve according to claim 1, wherein said industrial strapping
or ribbon material has a thickness of 0.30 mm or more, and a width of 10 mm or more.
4. The fabric, belt or sleeve according to claim 1, wherein said belt or sleeve is permeable
or impermeable to air and/or water.
5. The fabric, belt or sleeve according to claim 4, wherein said belt or sleeve is permeable
to air and/or water, and through voids or holes in said belt or sleeve are created
using a mechanical or thermal means.
6. The fabric, belt or sleeve according to claim 5, wherein said through voids or holes
are formed in a predetermined size, shape or orientation.
7. The fabric, belt or sleeve according to claim 6, wherein said through voids or holes
have a nominal diameter in the range of 0.0127 cm (0.005 inches) to 0.0254 cm (0.01
inches) or more.
8. The fabric, belt or sleeve according to claim 1, further comprising one or more layers
of woven or nonwoven materials, MD or CD yarn arrays, spirally wound strips of woven
material having a width less than the width of the belt or sleeve.
9. The fabric, belt or sleeve according to claim 1, wherein said belt or sleeve has a
texture on one or both surfaces.
10. The fabric, belt or sleeve according to claim 9, wherein said texture is provided
by sanding, graving, embossing or etching.
11. The fabric, belt or sleeve according to claim 1, wherein said belt or sleeve is smooth
on one or both surfaces.
12. The fabric, belt or sleeve according to claim 1, wherein said belt or sleeve comprises
at least two layers of strapping materials spirally wound in opposite directions to
each other, or opposite to the MD.
13. The fabric, belt or sleeve according to claim 1, further comprising a functional coating
on one or both sides of the belt or sleeve.
14. The fabric, belt or sleeve according to claim 8, wherein said one or more layers is
provided on one or both sides of the belt or sleeve, or in between two layers of strapping.
15. The fabric, belt or sleeve according to claim 1, wherein adjacent strips of polymeric
material are mechanically interlocked.
16. The fabric, belt or sleeve according to claim 13, wherein the functional coating has
a texture on its top surface.
17. A method for forming an endless fabric, belt or sleeve (1), the method comprising
the steps of: spirally winding one or more strips of polymeric material (16) around
a plurality of rolls,
wherein said one or more strips of polymeric material is an industrial strapping or
ribbon material; and
joining edges of adjacent strips of material;
wherein the strapping or ribbon material is uniaxially oriented and has at least twice
the tensile modulus of a biaxially oriented material and up to ten times the modulus
of an extruded material;
and reinforcing said industrial strapping or ribbon material in the MD of the fabric,
belt or
sleeve with fibers, yarns, monofilaments or multifilament yarns,
wherein the reinforcing material is made of a material selected from the group consisting
of aramids, thermoplastic polymers, thermosetting polymers, glass and carbon,
wherein the melting temperature of the strapping or ribbon material is lower than
the melting temperature of the reinforcing material.
18. The method according to claim 17, wherein one or more strapping or ribbon materials
are joined by laser, infrared or ultrasonic welding.
19. The method according to claim 17, wherein said industrial strapping or ribbon material
has a thickness of 0.30 mm or more, and a width of 10 mm or more.
20. The method according to claim 17, wherein said belt or sleeve is made permeable or
impermeable to air and/or water.
21. The method according to claim 20, where said belt or sleeve is made permeable to air
and/or water by creating through voids or holes in said belt or sleeve using a mechanical
or thermal means.
22. The method according to claim 21, wherein said through voids or holes are formed in
a predetermined size, shape or orientation.
23. The method according to claim 22, wherein said through voids or holes have a nominal
diameter in the range of 0.0127 cm (0.005 inches) or 0.0254 cm (0.01 inches) or more.
24. The method according to claim 17, further comprising the step of:
applying to an upper and/or lower surface of said belt or sleeve one or more layers
of woven or nonwoven materials, MD or CD yarn arrays, spirally wound strips of woven
material having a width less than the width of the belt or sleeve.
25. The method according to claim 17, wherein adjacent strips of polymeric material are
mechanically interlocked.
26. The method according to claim 17, wherein said belt or sleeve is provided with a texture
on one or both surfaces.
27. The method according to claim 26, wherein said texture is provided by sanding, graving,
embossing or etching.
28. The method according to claim 17, wherein said belt or sleeve is smooth on one or
both surfaces.
29. The method according to claim 17, wherein said belt or sleeve comprises at least two
layers of strapping materials spirally wound in opposite directions to each other,
or opposite to the MD.
30. The method according to claim 17, further comprising the step of coating on one or
both sides of the belt or sleeve with a functional coating.
31. The method according to claim 24, wherein said one or more layers is provided on one
or both sides of the belt or sleeve, or in between two layers of strapping.
32. The method according to claim 30, further comprising the step of providing a texture
to the functional coating.
1. Endloses technisches Gewebe, Band oder Hülse (10) umfassend:
einen oder mehrere spiralförmig gewickelte Streifen von Polymermaterial (16), wobei
der eine oder mehrere Streifen von Polymermaterial ein technisches Umreifungs- oder
Bandmaterial sind,
wobei das Umreifungs- oder Bandmaterial uniaxial ausgerichtet ist und zumindest das
Zweifache des Zugmoduls eines biaxial ausgerichteten Materials und bis zum Zehnfachen
des Moduls eines extrudierten Materials aufweist,
dadurch gekennzeichnet, dass das technische Umreifungs- oder Bandmaterial ein Verstärkungsmaterial enthält, das
in der MD des Bandes oder der Hülse, ausgewählt aus der Gruppe bestehend aus Fasern,
Garnen, Monofilamenten und Multifilamentgarnen, ausgerichtet ist, wobei das Verstärkungsmaterial
aus einem Material hergestellt ist, das aus der aus Aramiden, thermoplastischen Polymeren,
wärmehärtbaren Polymeren, Glas und Kohlenstoff bestehenden Gruppe ausgewählt ist,
und wobei die Schmelztemperatur des Umreifungs- oder Bandmaterials niedriger als die
Schmelztemperatur des Verstärkungsmaterials ist.
2. Gewebe, Band oder Hülse nach Anspruch 1, wobei das Gewebe, das Band oder die Hülse
ein Substrat zur Verwendung in einem Formungsgewebe, Pressgewebe, Trockensieb, Durchlufttrockner-(TAD)-Gewebe,
einer Schuhpresse oder Transfer- oder Kalanderband, einem Prozessband, angewandt in
einem Airlaid-Schmelzblasen-, Spun-Bonding- oder Wasserstrahlverfestigungsverfahren,
Bogentransferband, Langspaltpresse (LNP) oder Kalanderband, Wellenpappenband, Sanforierband,
Gerberband, Zellstoffbildungs- oder Zellstoffpressband, Entwässerungsband auf einer
Double-Nip-Thickener-(DNT)-Deinking-Maschine oder einem Schlammentwässerungsband ist.
3. Gewebe, Band oder Hülse nach Anspruch 1, wobei das technische Umreifungs- oder Bandmaterial
eine Dicke von 0,30 mm oder mehr und eine Breite von 10 mm oder mehr aufweist.
4. Gewebe, Band oder Hülse nach Anspruch 1, wobei das Band oder die Hülse für Luft und/oder
Wasser durchlässig oder undurchlässig ist.
5. Gewebe, Band oder Hülse nach Anspruch 4, wobei das Band oder die Hülse für Luft und/oder
Wasser durchlässig ist, und durchgehende Hohlräume oder Löcher in dem Band oder der
Hülse unter Anwendung eines mechanischen oder thermischen Mittels erzeugt sind.
6. Gewebe, Band und Hülse nach Anspruch 5, wobei die durchgehenden Hohlräume oder Löcher
in einer vorgegebenen Größe, Form oder Ausrichtung gebildet sind.
7. Gewebe, Band oder Hülse nach Anspruch 6, wobei die durchgehenden Hohlräume oder Löcher
einen Nenndurchmesser im Bereich von 0,0127 cm (0,005 Zoll) bis 0,0254 cm (0.01 Zoll)
oder mehr aufweisen.
8. Gewebe, Band oder Hülse nach Anspruch 1, zusätzlich umfassend eine oder mehrere Schichten
von Gewebe- oder Vliesmaterialien, MD- oder CD-Garnanordnungen, spiralförmig gewickelten
Streifen eines Gewebematerials mit einer Breite, die kleiner als die Breite des Bandes
oder der Hülse ist.
9. Gewebe, Band oder Hülse nach Anspruch 1, wobei das Band oder die Hülse eine Textur
auf einer oder beiden Flächen aufweist.
10. Gewebe, Band oder Hülse nach Anspruch 9, wobei die Textur durch Schleifen, Gravieren,
Prägen oder Ätzen vorgesehen ist.
11. Gewebe, Band oder Hülse nach Anspruch 1, wobei das Band oder die Hülse auf einer oder
beiden Flächen glatt ist.
12. Gewebe, Band oder Hülse nach Anspruch 1, wobei das Band oder die Hülse zumindest zwei
Schichten von Umreifungsmaterialien umfasst, die in entgegengesetzten Richtungen zueinander
oder entgegengesetzt zur MD spiralförmig gewickelt sind.
13. Gewebe, Band oder Hülse nach Anspruch 1, zusätzlich umfassend eine funktionelle Beschichtung
auf einer oder beiden Seiten des Bandes oder der Hülse.
14. Gewebe, Band oder Hülse nach Anspruch 8, wobei die eine oder mehrere Schichten auf
einer oder beiden Seiten des Bandes oder der Hülse oder zwischen zwei Umreifungsschichten
vorgesehen sind.
15. Gewebe, Band oder Hülse nach Anspruch 1, wobei angrenzende Streifen von Polymermaterial
mechanisch miteinander verbunden sind.
16. Gewebe, Band oder Hülse nach Anspruch 13, wobei die funktionelle Beschichtung eine
Textur auf ihrer oberen Fläche aufweist.
17. Verfahren zum Bilden eines endlosen Gewebes, Bandes oder einer Hülse (1), welches
Verfahren die folgenden Schritte umfasst:
spiralförmiges Wickeln von einem oder mehreren Streifen von Polymermaterial (16) um
eine Vielzahl von Rollen, wobei der eine oder mehrere Streifen von Polymermaterial
ein technisches Umreifungs- oder Bandmaterial sind; und Verbinden von Kanten benachbarter
Materialstreifen;
wobei das Umreifungs- oder Bandmaterial uniaxial ausgerichtet ist und zumindest das
Zweifache des Zugmoduls eines biaxial ausgerichteten Materials und bis zum Zehnfachen
des Moduls eines extrudierten Materials aufweist;
und Verstärken des technischen Umreifungs- oder Bandmaterials in der MD des Gewebes,
Bandes oder der Hülse mit Fasern, Garnen, Monofilamenten oder Multifilamentgarnen,
wobei das Verstärkungsmaterial aus einem Material hergestellt ist, das aus der aus
Aramiden, thermoplastischen Polymeren, wärmehärtbaren Polymeren, Glas und Kohlenstoff
bestehenden Gruppe ausgewählt ist,
wobei die Schmelztemperatur des Umreifungs- oder Bandmaterials niedriger als die Schmelztemperatur
des Verstärkungsmaterials ist.
18. Verfahren nach Anspruch 17, wobei ein oder mehrere Umreifungs- oder Bandmaterialien
durch Laser-, Infrarot- oder Ultraschallschweißen zusammengefügt werden.
19. Verfahren nach Anspruch 17, wobei das technische Umreifungs- oder Bandmaterial eine
Dicke von 0,30 mm oder mehr und eine Breite von 10 mm oder mehr aufweist.
20. Verfahren nach Anspruch 17, wobei das Band oder die Hülse für Luft und/oder Wasser
durchlässig oder undurchlässig gemacht wird.
21. Verfahren nach Anspruch 20, wobei das Band oder die Hülse durch das Erzeugen von durchgehenden
Hohlräumen oder Löchern in dem Band oder der Hülse unter Anwendung eines mechanischen
oder thermischen Mittels für Luft und/oder Wasser durchlässig gemacht wird.
22. Verfahren nach Anspruch 21, wobei die durchgehenden Hohlräume oder Löcher in einer
vorgegebenen Größe, Form oder Ausrichtung gebildet werden.
23. Verfahren nach Anspruch 22, wobei die durchgehenden Hohlräume oder Löcher einen Nenndurchmesser
im Bereich von 0,0127 cm (0,005 Zoll) oder 0,0254 cm (0.01 Zoll) oder mehr aufweisen.
24. Verfahren nach Anspruch 17, ferner umfassend den folgenden Schritt:
Aufbringen von einer oder mehreren Schichten von Gewebe- oder Vliesmaterialien, MD-
oder CD-Garnanordnungen, spiralförmig gewickelten Streifen eines Gewebematerials mit
einer Breite, die kleiner als die Breite des Bandes oder der Hülse ist, auf eine untere
und/oder obere Fläche des Bandes oder der Hülse.
25. Verfahren Anspruch 17, wobei angrenzende Streifen von Polymermaterial mechanisch miteinander
verbunden werden.
26. Verfahren nach Anspruch 17, wobei das Band oder die Hülse mit einer Textur auf einer
oder beiden Flächen versehen wird.
27. Verfahren nach Anspruch 26, wobei die Textur durch Schleifen, Gravieren, Prägen oder
Ätzen vorgesehen wird.
28. Verfahren nach Anspruch 17, wobei das Band oder die Hülse auf einer oder beiden Flächen
glatt ist.
29. Verfahren nach Anspruch 17, wobei das Band oder die Hülse zumindest zwei Schichten
von Umreifungsmaterialien umfasst, die in entgegengesetzten Richtungen zueinander
oder entgegengesetzt zur MD spiralförmig gewickelt sind.
30. Verfahren nach Anspruch 17, zusätzlich umfassend den Schritt des Beschichtens auf
einer oder beiden Seiten des Bandes oder der Hülse mit einer funktionellen Beschichtung.
31. Verfahren nach Anspruch 24, wobei die eine oder mehrere Schichten auf einer oder beiden
Seiten des Bandes oder der Hülse oder zwischen zwei Umreifungsschichten vorgesehen
werden.
32. Verfahren nach Anspruch 30, zusätzlich umfassend den Schritt des Vorsehens einer Textur
für die funktionelle Beschichtung.
1. Tissu industriel sans fin, courroie ou manchon (10) comprenant :
une ou plusieurs bandes enroulées en spirale de matériau polymère (16), ladite une
ou plusieurs bandes de matériau polymère étant un matériau industriel de cerclage
ou de ruban,
le matériau de cerclage ou de ruban étant uniaxialement orienté et présentant au moins
deux fois le module de traction d'un matériau orienté biaxialement et jusqu'à dix
fois le module d'un matériau extrudé,
caractérisé en ce que le matériau industriel de cerclage ou de ruban comprend un matériau de renforcement
orienté dans le MD de la courroie ou le manchon choisi dans le groupe constitué de
fibres, fils, fils monofilaments et multifilaments, le matériau de renforcement étant
fait d'un matériau choisi dans le groupe constitué par les aramides, les polymères
thermoplastiques, les polymères thermodurcissables, le verre et le carbone,
et la température de fusion du matériau de cerclage ou de ruban étant inférieure à
la température de fusion du matériau de renforcement.
2. Tissu, courroie ou manchon selon la revendication 1, dans lequel ledit tissu, courroie
ou manchon est un substrat destiné à être utilisé dans un tissu de formage, tissu
de presse, tissu de séchage, tissu de séchage par l'air (TAD), courroie de presse
à sabot ou de transfert ou de calandrage, une courroie de procédé utilisée dans les
procédés de soufflage à l'état fondu par voie aérolique, de liaison par filage ou
d'emmêlement hydraulique, courroie de transfert de feuille, courroie de calandrage
ou a longue ligne de pincement (LNP), courroie onduleuse, courroie de sanforisation,
courroie de tannerie, courroie de formation ou de pression de pulpage, courroie de
déshydratation sur une machine de désencrage d'épaississement à double pincement (DNT)
ou une courroie de déshydratation des boues.
3. Tissu, courroie ou manchon selon la revendication 1, dans lequel ledit matériau industriel
de cerclage ou de ruban présente une épaisseur de 0,30 mm ou plus, et une largeur
de 10 mm ou plus.
4. Tissu, courroie ou manchon selon la revendication 1, dans lequel ladite courroie ou
ledit manchon est perméable ou imperméable à l'air et / ou à l'eau.
5. Tissu, courroie ou manchon selon la revendication 4, dans lequel ladite courroie ou
ledit manchon est perméable à l'air et / ou à l'eau, et des vides traversants ou des
trous dans ladite courroie ou ledit manchon sont créés en utilisant un moyen mécanique
ou thermique.
6. Tissu, courroie ou manchon selon la revendication 5, dans lequel lesdits vides traversants
ou trous sont formés selon une taille, une forme ou une orientation prédéterminée.
7. Tissu, courroie ou manchon selon la revendication 6, dans lequel lesdits vides traversants
ou trous présentent un diamètre nominal dans la plage de 0,0127 cm (0,005 pouce) à
0,0254 cm (0,01 pouce) ou plus.
8. Tissu, courroie ou manchon selon la revendication 1, comprenant en outre une ou plusieurs
couches de matériaux tissés ou non tissés, réseaux de fils MD ou CD, bandes enroulées
en spirale de matériau tissé ayant une largeur inférieure à la largeur de la courroie
ou du manchon.
9. Tissu, courroie ou manchon selon la revendication 1, dans lequel ladite courroie ou
ledit manchon a une texture sur une ou les deux surfaces.
10. Tissu, courroie ou manchon selon la revendication 9, dans lequel ladite texture est
fournie par ponçage, gravure, gaufrage ou gravure.
11. Tissu, courroie ou manchon selon la revendication 1, dans lequel ladite courroie ou
ledit manchon est lisse sur une ou les deux surfaces.
12. Tissu, courroie ou manchon selon la revendication 1, dans lequel ladite courroie ou
ledit manchon comprend au moins deux couches de matériaux de cerclage enroulées en
spirale dans des directions opposées l'une à l'autre, ou opposées à la MD.
13. Tissu, courroie ou manchon selon la revendication 1, comprenant en outre un revêtement
fonctionnel sur un ou les deux côtés de la courroie ou du manchon.
14. Tissu, courroie ou manchon selon la revendication 8, dans lequel ladite une ou plusieurs
couches est prévue sur un ou les deux côtés de la courroie ou du manchon, ou entre
deux couches de cerclage.
15. Tissu, courroie ou manchon selon la revendication 1, dans lequel des bandes adjacentes
de matériau polymère sont interverrouillées mécaniquement.
16. Tissu, courroie ou manchon selon la revendication 13, dans lequel le revêtement fonctionnel
a une texture sur sa surface supérieure.
17. Procédé de formation d'un tissu sans fin, d'une courroie ou d'un manchon (1), le procédé
comprenant les étapes consistant à :
enrouler en spirale une ou plusieurs bandes de matériau polymère (16) autour d'une
pluralité de rouleaux, ladite une ou plusieurs bandes de matériau polymère étant un
matériau industriel de cerclage ou de ruban ; et
joindre des bords de bandes de matériau adjacentes ;
le matériau de cerclage ou de ruban étant uniaxialement orienté et présentant au moins
deux fois le module de traction d'un matériau orienté biaxialement et jusqu'à dix
fois le module d'un matériau extrudé ;
et renforcer ledit matériau industriel de cerclage ou de ruban dans le MD du tissu,
de la courroie ou du manchon avec fibres, fils, fils monofilaments et multifilaments,
le matériau de renforcement étant fait d'un matériau choisi dans le groupe constitué
par les aramides, les polymères thermoplastiques, les polymères thermodurcissables,
le verre et le carbone,
la température de fusion du matériau de cerclage ou de ruban étant inférieure à la
température de fusion du matériau de renforcement.
18. Procédé selon la revendication 17, dans lequel l'un ou plusieurs matériaux de cerclage
ou de ruban sont joints par le soudage par laser, infrarouge ou par ultrasons.
19. Procédé selon la revendication 17, dans lequel ledit matériau industriel de cerclage
ou de ruban présente une épaisseur de 0,30 mm ou plus, et une largeur de 10 mm ou
plus.
20. Procédé selon la revendication 17, dans lequel ladite courroie ou ledit manchon est
perméable ou imperméable à l'air et / ou à l'eau.
21. Procédé selon la revendication 20, dans lequel ladite courroie ou ledit manchon est
perméable à l'air et / ou à l'eau en créant des vides traversants ou des trous dans
ladite courroie ou ledit manchon en utilisant un moyen mécanique ou thermique.
22. Procédé selon la revendication 21, dans lequel lesdits vides traversants ou trous
sont formés selon une taille, une forme ou une orientation prédéterminée.
23. Procédé selon la revendication 22, dans lequel lesdits vides traversants ou trous
présentent un diamètre nominal dans la plage de 0,0127 cm (0,005 pouce) à 0,0254 cm
(0,01 pouce) ou plus.
24. Procédé selon la revendication 17, comprenant en outre l'étape consistant à :
appliquer sur une surface supérieure et / ou inférieure de ladite courroie ou dudit
manchon une ou plusieurs couches de matériaux tissés ou non tissés, réseaux de fils
MD ou CD, bandes enroulées en spirale de matériau tissé ayant une largeur inférieure
à la largeur de la courroie ou du manchon.
25. Procédé selon la revendication 17, dans lequel des bandes adjacentes de matériau polymère
sont interverrouillées mécaniquement.
26. Procédé selon la revendication 17, dans lequel ladite courroie ou ledit manchon est
pourvu d'une texture sur une ou les deux surfaces.
27. Procédé selon la revendication 26, dans lequel ladite texture est fournie par ponçage,
gravure, gaufrage ou gravure.
28. Procédé selon la revendication 17, dans lequel ladite courroie ou ledit manchon est
lisse sur une ou les deux surfaces.
29. Procédé selon la revendication 17, dans lequel ladite courroie ou ledit manchon comprend
au moins deux couches de matériaux de cerclage enroulées en spirale dans des directions
opposées l'une à l'autre, ou opposées à la MD.
30. Procédé selon la revendication 17, comprenant en outre l'étape de revêtement sur un
ou les deux côtés de la courroie ou du manchon avec un revêtement fonctionnel.
31. Procédé selon la revendication 24, dans lequel ladite une ou plusieurs couches est
prévue sur un ou les deux côtés de la courroie ou du manchon, ou entre deux couches
de cerclage.
32. Procédé selon la revendication 30, comprenant en outre l'étape consistant à fournir
une texture au revêtement fonctionnel.