GB1590763A - Manufacture of felts for papermaking machines - Google Patents
Manufacture of felts for papermaking machines Download PDFInfo
- Publication number
- GB1590763A GB1590763A GB45269/77A GB4526977A GB1590763A GB 1590763 A GB1590763 A GB 1590763A GB 45269/77 A GB45269/77 A GB 45269/77A GB 4526977 A GB4526977 A GB 4526977A GB 1590763 A GB1590763 A GB 1590763A
- Authority
- GB
- United Kingdom
- Prior art keywords
- felt
- sheet
- fibres
- surface layer
- layer
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21F—PAPER-MAKING MACHINES; METHODS OF PRODUCING PAPER THEREON
- D21F7/00—Other details of machines for making continuous webs of paper
- D21F7/08—Felts
- D21F7/083—Multi-layer felts
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B5/00—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts
- B32B5/22—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts characterised by the presence of two or more layers which are next to each other and are fibrous, filamentary, formed of particles or foamed
- B32B5/24—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts characterised by the presence of two or more layers which are next to each other and are fibrous, filamentary, formed of particles or foamed one layer being a fibrous or filamentary layer
- B32B5/26—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts characterised by the presence of two or more layers which are next to each other and are fibrous, filamentary, formed of particles or foamed one layer being a fibrous or filamentary layer another layer next to it also being fibrous or filamentary
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B5/00—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts
- B32B5/02—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts characterised by structural features of a fibrous or filamentary layer
- B32B5/024—Woven fabric
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B5/00—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts
- B32B5/02—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts characterised by structural features of a fibrous or filamentary layer
- B32B5/06—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts characterised by structural features of a fibrous or filamentary layer characterised by a fibrous or filamentary layer mechanically connected, e.g. by needling to another layer, e.g. of fibres, of paper
Description
(54) MANUFACTURE OF FELTS FOR PAPERMAKING
MACHINES
(71) We, HUYCK CORPORATION, a corporation organized under the laws of the
State of New York, United States of
America, of Wake Forest, North Carolina 27587, United States of America, do hereby declare the invention, for which we pray that a Patent may be granted to us, and the method by which it is to be performed, to be paricularly described in and by the following statement: This invention relates to a method of making a felt for use in the press section of the papermaking machine, and to a felt made by the method.
In general, press felts are used in papermaking machines to support the moist, freshly formed paper web as it encounters rolls which serve to extract water from the moist paper web. In addition to serving as a support for the paper web, the press felt serves as a temporary receptacle for the water removed from the paper sheet. The press felt normally has a conveyor belt-like shape and during the various operations previously mentioned, a large amount of water accumulates in the press felt which is removed by suction or various other drainage devices, usually after the paper web and press felt are no longer in direct contact.During the breaking-in or runningin period of most known felts, it is usually necessary to run the papermaking machine at a reduced speed and/or to increase the heat energy flowing into the dryer section above the level which will be necessary when the belt has been run-in. Since the amount of paper produced by a papermaking machine is largely dependent upon the speed of the machine, any slowing down caused by, for example, the required breakin period in papermakers' felts, results in the machine functioning at less than optimum economic efficiency.
Paper sheet dewatering, sheet surface smoothness, sheet pick-up and sheet carrying, as well as a variety of other performance characteristics, are sensitive to felt design. It has been observed that the phy- sical characteristics of felts change during their useful operating life, the greater change occurring during the first hours of felt operation. Most press felts require an initial breaking-in period before peak water removal efficiency is achieved. This breaking-in period usually lasts for several hours and, in some cases, lasts several days.During the breaking-in period, performance of the press felt may be unsatisfactory in terms of dptimum water removal from the paper web and pick-up and carrying of the paper web from the adjacent forming section or from an adjacent felt, thereby resulting in lost paper production and/or higher paper production costs due to lower operating speeds.
The present invention is concerned with a method of making a felt which will reduce the problem of relatively poor paper machine performance during the early part of the life of the felt.
According to this invention there is provided a method of making a felt for a papermaking machine comprising securing to a base fabric layer a surface layer made from fibres at least a minor proportion of which are fibres (flat fibres) having in crosssection a thickness less than the width thereof.
The invention also provides a felt for a papermaking machine made by a method as set forth in the preceding paragraph.
The invention will now be described in more detail with reference to the accompanying drawings in which:
Figure 1 is a schematic cross-sectional view showing on an enlarged scale the structure of the sheet-contacting surface layer applied to a woven base layer in one embodiment of the invention, and
Figure 2 is a schematic cross-sectional view similar to Figure 1 illustrating another embodiment of the present invention.
Referring first to Figure 1 of the drawings, a non-woven sheet-contacting surface layer 1 containing flat fibres 2 as well as conventional fibres 3 is deposited on and directly joined to a base layer 4, which in the embodiment illustrated, comprises a woven fabric. The sheet-contacting surface layer 1 may be joined to the base layer 4 in any conventional fashion, preferably by needling. In another embodiment of the invention illustrated in Figure 2, the sheetcontacting surface layer 1 is joined to the base layer 4 through an intermediate batt of nonwoven fibres which may comprise either natural or synthetic fibres, such batt layer adding additional bulk and water reception properties to the structure.As in the case of the sheet-contacting surface layer 1, the batt layer 5 may be joined to the fabric in any conventional manner and both the sheet-contacting surface layer and the batt layer may be joined to the base layer 4 by one or more joint needling operations.
In accordance with the invention, the sheet-contacting layer 1 in either of the foregoing embodiments may be composed entirely of flat fibres, although preferably it will comprise a blend of flat and conventional fibres, as has been illustrated. The flat fibres preferably have mutually perpendicular diameters having a ratio of 3:1 or greater, i.e. fibres with cross-sectional dimensions which are at least three times as long as they are wide, and are to be contrasted with the normal circular-section fibres which are currently used in constructing the batt or surface layer of prior art papermakers' felt. Preferably, the flat fibres will constitute at least 50% of the fibres of the sheet-contacting surface layer. However, depending upon the particular press configuration and paper machine design, as little as 10% flat fibres may be used.The cross-sectional dimensions of the flat fibres also will have a bearing on the composition of the sheet-contacting surface layer. For example, for best results, flat fibres having a 3:1 cross-sectional ratio should be mixed with fewer conventional (i.e. circularsection) fibres than flat fibres having a 4:1 or 7:1 ratio.
The flat fibres can be formed from any of the well-known natural or synthetic fibres which are usually used in constructing papermakers' felts, including such animal fibres as wool, as well as such synthetic fibres as polyacrylics, such as Orlon (R.T.M.), polyesters, such as Dacron (R.T.M.), and polyamides, such as Nylon.
Likewise, the remaining portion of the sheet-contacting surface layer may be made from any of the synthetic fibres which have been previously mentioned. Similarly, the batt layer 5 can be composed of any of the aforementioned types of fibres. The sheetcontacting layer 1 and the intermediate batt layer 5 can be formed by carding, air-laying or other well-known procedures which are effective to orient the fibres in a uniform manner as to thickness and density Alternatively, the intermediate batt layer may be of a woven construction.
Although not shown, it is contemplated that the use of flat fibres in the sheetcontacting layer 1 may be incorporated in a number of prior art felt structures, such as described in Fekete's U.S. Patent No.
3 928 699 and the Wicker et al U.S. Patent
No. 3 214 327, both of which teach dual layer felt construction to which the sheetcontacting layer of the present invention can be applied. In addition, one or more layers may be inserted in multiple planes between the base layer 4 and the sheetcontacting layer 1, and it is to be understood that the term sheet-contacting layer means the layer of the felt which comes into contact with the paper web. It will also be understood that the base layer 4 will be formed from either natural or synthetic materials of the types previously mentioned in connection with the sheetcontacting and batt layers. The sheetcontacting and the batt layers can be joined to one another by mechanical methods, such as needling in a needle loom, or by the use of adhesives.The base layer may be a woven structure having a plain weave, or any other suitable weave configuration may be used, such as twill or 4-harness satin. Alternately, the base layer may comprise a nonwoven fabric.
The following example illustrates a method of making a felt according to the teachings of the present invention:
A base layer was woven endless with a reverse broken twill weave containing approximately 4.2 warp yarns per centimetre and 7.1 weft yarns per centimetre.
The weft and warp yarns were Nylon and the weight of the base layer was approximately 560 g/m2.
The intermediate nonwoven batt layer was made of Nylon fibres, approximately 7.6 centimetres in length and 43 microns in diameter It was needled on top of the woven base layer in two layers whose combined weight was 435 gum2.
The sheet-contacting surface layer was made of a blend of Nylon fibres having a diameter of about 43 microns and modacrylic fibres having approximately a height of 8.4 microns, a width of 59 microns and a length of 11.4 centimetres.
The weight of Nylon fibres was about 92 g/m2 and that of the modacrylic was the same. The sheet-contacting layer was needled on top of the intermediate batt layer in a single layer weighing about 184 glum2. The total weight of the finished felt was approximately 1180 g/m2.
The described structure of the felt is based on the observation that the originally round or irregularly shaped felt surface fibres tend to flatten out during operation.
As surface fibres flatten, the area of interface between felt and paper increases lead ing to greater adhesion between felt and sheet and therefore to improved sheet pickup and sheet-carrying performance. In addition, the increased sheet/felt interface area provides a more effective sheet support in the press leading to more efficient sheet dewatering. However, since fibre flattening under papermaking conditions requires time, during the early part of felt life the papermaker must do without the resultant benefits.
The felts described above are made with flat fibres already present in the sheetcontacting surface of the new felt, rather than await the natural process of fibre deformation, in order to substantially, or in some cases totally, eliminate the early period of relatively poor performance.
In utilizing a sheet-contacting surface layer comprising flat fibres as opposed to round or irregularly shaped fibres as has been used in the prior art, it is possible to increase the actual area available on the surface of the felt for contact with the paper web. Without intending to present any particular theory of operation of the felts particularly described above, it is believed that felts having a sheet-contacting surface layer comprising flat fibres allow a more efficient transfer of water between the paper web and press felts when the mechanical forces of the presses present in the press section of the paper machine act on the paper web to transfer the water contained in the paper web to the press felt.
The use of flat fibres in the sheetcontacting surface layer allows for a relatively smooth surface to be presented to the paper web which comes in contact with the felt structure. The result of this is that marking of the paper web is minimized.
Further, by utilizing flat fibres in the sheetcontacting surface layer as described herein, it is also possible to reduce the tendency of the felt to fill up. By filling up, it is meant the action of wood fibres and small particles of other materials in the pulp to accumulate below the surface layer of a papermakers' felt so as to interfere with proper water removal, thereby reducing the efficiency of the papermaking process in the press section. The reduced filling up tendency is believed to occur because of the high fibre density present in the sheet-contacting surface layer of felts constructed in accordance with the invention.The high density flat fibres on the surface of the felt tend to retard the ability of the particles on the surface of the felt to work their way below the sheetcontacting surface layer so as to prevent their being easily removed by conventional feltWcleaning equipment which usually takes the form of a high pressure shower directed at the surface of the felt subsequent to its contact with the paper web.
In addition, felts constructed with a sheet-contacting surface layer comprised of flat fibres possess desirable properties with regard to paper web pick-up. By paper web pick-up, it is meant the ability of a press felt to transport the moist paper web as it leaves the forming fabric or wire which is the first step in the paper-forming process.
It is sometimes the case that the sheet, instead of attaching itself to the felt as it leaves the forming fabric, will instead move off the paper machine, thus causing a loss in the paper production process. Since the sheet-contacting surface layer of the webs particularly described above has a greater available surface area for contact with the paper web than known felts, it is believed that it will exhibit substantially better sheet pick-up properties than have heretofore been possible.
While the description above makes frequent reference to the term papermakers' felt, it should be understood that the invention is also applicable to dryer felts which are used to convey a paper web through the drying section of the paper machine.
WHAT WE CLAIM IS:
1. A method of making a felt for a papermaking machine comprising securing to a base fabric layer a surface layer made from fibres at least a minor proportion of which are fibres (flat fibres) having in cross-section a thickness less than the width thereof.
2. A method as claimed in claim 1, wherein said flat fibres constitute at least 10% by weight of said surface layer.
3. A method as claimed in claim 1, wherein said flat fibres constitute at least 50% by weight of said surface layer.
4. A method as claimed in any one of claims 1 to 3, wherein said surface layer is secured to the base layer and any intermediate layers by needling.
5. A method as claimed in any one of claims 1 to 3, wherein said base layer is a woven fabric.
6. A method as claimed in any one of claims 1 to 3, wherein a batt layer is secured to one surface of the base layer, and the surface layer is secured to the batt layer.
7. A method as claimed in claim 6, wherein the surface layer and the batt layer are needled to each other and to said base layer.
8. A method as claimed in claim 6 or claim 7 wherein the base layer is a woven fabric.
9. A method of making a felt for a papermaking machine which method is
**WARNING** end of DESC field may overlap start of CLMS **.
Claims (10)
1. A method of making a felt for a papermaking machine comprising securing to a base fabric layer a surface layer made from fibres at least a minor proportion of which are fibres (flat fibres) having in cross-section a thickness less than the width thereof.
2. A method as claimed in claim 1, wherein said flat fibres constitute at least 10% by weight of said surface layer.
3. A method as claimed in claim 1, wherein said flat fibres constitute at least 50% by weight of said surface layer.
4. A method as claimed in any one of claims 1 to 3, wherein said surface layer is secured to the base layer and any intermediate layers by needling.
5. A method as claimed in any one of claims 1 to 3, wherein said base layer is a woven fabric.
6. A method as claimed in any one of claims 1 to 3, wherein a batt layer is secured to one surface of the base layer, and the surface layer is secured to the batt layer.
7. A method as claimed in claim 6, wherein the surface layer and the batt layer are needled to each other and to said base layer.
8. A method as claimed in claim 6 or claim 7 wherein the base layer is a woven fabric.
9. A method of making a felt for a papermaking machine which method is
substantially as in the example hereinbefore described.
10. A felt for a papermaking machine made by a method as claimed in any one
of claims 1 to 9.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US73820876A | 1976-11-03 | 1976-11-03 | |
| US05/807,271 US4107367A (en) | 1976-11-03 | 1977-06-16 | Papermakers felts |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| GB1590763A true GB1590763A (en) | 1981-06-10 |
Family
ID=27113331
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB45269/77A Expired GB1590763A (en) | 1976-11-03 | 1977-10-31 | Manufacture of felts for papermaking machines |
Country Status (8)
| Country | Link |
|---|---|
| JP (1) | JPS5358007A (en) |
| AT (1) | AT363775B (en) |
| AU (1) | AU504765B2 (en) |
| BR (1) | BR7707350A (en) |
| CA (1) | CA1061621A (en) |
| DE (1) | DE2749043B2 (en) |
| FR (1) | FR2370123A1 (en) |
| GB (1) | GB1590763A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2200867A (en) * | 1987-01-21 | 1988-08-17 | Tamfelt Oy Ab | Papermakers felt leaving a smooth surface |
| WO2007124966A1 (en) * | 2006-04-28 | 2007-11-08 | Voith Patent Gmbh | Dewatering tissue press fabric for an atmos system and press section of a paper machine using the dewatering fabric |
Families Citing this family (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2847327C2 (en) * | 1978-05-17 | 1984-02-23 | JWI Ltd., Montreal, Quebec | Drying fabrics for paper machines |
| ZA815443B (en) * | 1980-12-10 | 1982-11-24 | Albany Int Corp | Wet press felt for papermaking machine |
| JPS5816598U (en) * | 1981-07-27 | 1983-02-01 | 日本原子力研究所 | Lead container for disc-shaped radioactive brachytherapy source |
| JPS58117773U (en) * | 1982-02-05 | 1983-08-11 | ユニチカ株式会社 | Short fibers for non-woven fabrics |
| US4414263A (en) * | 1982-07-09 | 1983-11-08 | Atlanta Felt Company, Inc. | Press felt |
| US4482601A (en) * | 1983-05-31 | 1984-11-13 | Albany International Corp. | Wet press papermakers felt and method of fabrication |
| AT395184B (en) * | 1990-07-04 | 1992-10-12 | Andritz Ag Maschf | DEVICE FOR TREATING CELLULOSE AND OR OR MULTIPLE MIXTURES OR SUSPENSIONS |
| DE9211776U1 (en) * | 1992-09-02 | 1992-11-12 | Wuerttembergische Filztuchfabrik D. Geschmay Gmbh, 7320 Goeppingen, De | |
| US6175996B1 (en) * | 1999-07-22 | 2001-01-23 | Weavexx Corporation | Method of forming a papermakers' felt |
| JP2006144149A (en) | 2004-11-17 | 2006-06-08 | Ichikawa Co Ltd | Transporting felt for papermaking, and press device of paper machine having the transporting felt for papermaking |
| JP4958447B2 (en) * | 2006-02-06 | 2012-06-20 | イチカワ株式会社 | Paper transport felt |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2959839A (en) * | 1955-05-18 | 1960-11-15 | Du Pont | Linear condensation polymer fiber |
| US2816349A (en) * | 1955-11-30 | 1957-12-17 | Du Pont | Fibers and fabrics |
| US3030690A (en) * | 1960-07-20 | 1962-04-24 | Appleton Mills | Method of making papermaker's felt |
| US3392079A (en) * | 1964-05-22 | 1968-07-09 | Huyck Corp | Papermakers' felt |
| GB1236780A (en) * | 1967-11-06 | 1971-06-23 | Huyck Corp | Improvements in papermaking apparatus |
| DE2134853A1 (en) * | 1971-07-13 | 1973-02-08 | Bayer Ag | EDGE REINFORCEMENT SYSTEM FOR THE MANUFACTURING OF HIGHLY DEMANDING FOAM CONSTRUCTIONS |
| JPS5013245B2 (en) * | 1972-06-10 | 1975-05-19 | ||
| JPS5218302A (en) * | 1975-08-01 | 1977-02-10 | Fuji Photo Film Co Ltd | Magnetic sheet recording/playing method |
-
1977
- 1977-10-31 GB GB45269/77A patent/GB1590763A/en not_active Expired
- 1977-10-31 CA CA289,944A patent/CA1061621A/en not_active Expired
- 1977-11-01 BR BR7707350A patent/BR7707350A/en unknown
- 1977-11-02 DE DE2749043A patent/DE2749043B2/en not_active Withdrawn
- 1977-11-02 FR FR7732960A patent/FR2370123A1/en active Granted
- 1977-11-02 AT AT0782577A patent/AT363775B/en not_active IP Right Cessation
- 1977-11-03 AU AU30291/77A patent/AU504765B2/en not_active Expired
- 1977-11-04 JP JP13239277A patent/JPS5358007A/en active Granted
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2200867A (en) * | 1987-01-21 | 1988-08-17 | Tamfelt Oy Ab | Papermakers felt leaving a smooth surface |
| GB2200867B (en) * | 1987-01-21 | 1991-04-17 | Tamfelt Oy Ab | A process band |
| WO2007124966A1 (en) * | 2006-04-28 | 2007-11-08 | Voith Patent Gmbh | Dewatering tissue press fabric for an atmos system and press section of a paper machine using the dewatering fabric |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5358007A (en) | 1978-05-25 |
| DE2749043A1 (en) | 1978-05-24 |
| JPS5631399B2 (en) | 1981-07-21 |
| FR2370123B1 (en) | 1979-07-13 |
| BR7707350A (en) | 1978-06-20 |
| AU3029177A (en) | 1979-05-10 |
| AT363775B (en) | 1981-08-25 |
| FR2370123A1 (en) | 1978-06-02 |
| ATA782577A (en) | 1981-01-15 |
| DE2749043B2 (en) | 1980-12-04 |
| CA1061621A (en) | 1979-09-04 |
| AU504765B2 (en) | 1979-10-25 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PS | Patent sealed [section 19, patents act 1949] | ||
| PCNP | Patent ceased through non-payment of renewal fee |