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US 6,616,812 B2Granted
Anti-rewet felt for use in a papermaking machine
AssigneeVoith Paper Patent GmbH
InventorDavid A. Beck
Life of this patent
Estimating the term…
Abstract
An anti-rewet fabric is used for carrying a fiber web through an air press. The anti-rewet fabric includes at least one air distribution fabric layer, one air distribution fabric layer being configured for contacting the fiber web, and a perforated film layer, the perforated film layer being made of a polyester film. The perforated film layer has a first film side and a second film side, the first film side being one of laminated and attached to the one air distribution fabric layer.
Claims31
A press unit for dewatering a fiber web, said press unit comprising:
- first and second opposing press elements, said first press element and said second press element together forming a nip therebetween;
- at least one anti-rewet fabric configured for carrying the fiber web through said nip, each said anti-rewet fabric having a first fabric side and a second fabric side, each said anti-rewet fabric including:
- at least one air distribution fabric layer, one air distribution fabric layer being configured for contacting the fiber web;
- a perforated film layer, said perforated film layer being comprised of one of a polyester film and a plastic film, said perforated film layer defining a plurality of holes therethrough separated from each other by a perforate distance, said perforated film layer having a first film side and a second film side, said first film side being one of laminated and attached to said one air distribution fabric layer, said second film side being directed toward one of said first and second press elements;
- and
- said air distribution fabric layer being structured and arranged with said perforated film layer to spread air in said air distribution fabric layer a distance greater than said perforate distance.
3 more elements
A press unit for dewatering a fiber web, said press unit comprising:
- first and second opposing press elements, said first press element and said second press element together forming a nip therebetween;
- at least one anti-rewet fabric configured for carrying the fiber web through said nip, each said anti-rewet fabric having a first fabric side and a second fabric side, each said anti-rewet fabric including:
- at least one air distribution fabric layer, one air distribution fabric layer being configured for contacting the fiber web;
- and
- a perforated film layer, said perforated film layer being comprised of one of a polyester film and a plastic film, said perforated film layer having a first film side and a second film side, said first film side being one of laminated and attached to said one air distribution fabric layer, said second film side being directed toward one of said first and second press elements;
- wherein said first press element is an enclosure, said second press element being a counter element positioned opposite said enclosure, said second film side being directed toward said counter element;
- said at least one anti-rewet fabric includes a first anti-rewet fabric, said press unit further comprising a second fabric, said first anti-rewet fabric being configured so as to be arranged between the fiber web and said counter element, said second fabric being configured so as to be arranged between the fiber web and said enclosure;
- and the press unit is part of a papermaking machine, said second fabric being configured for transferring the fiber web to a next station of said papermaking machine.
5 more elements
An anti-rewet fabric for carrying a fiber web through an air press, the anti-rewet fabric comprising:
- at least one air distribution fabric layer, one said air distribution fabric layer being configured for contacting the fiber web;
- a perforated film layer, said perforated film layer being comprised of one of a polyester film and a plastic film, said perforated film layer defining a plurality of holes therethrough separated from each other by a perforate distance, said perforated film layer having a first film side and a second film side, said first film side being one of laminated and attached to said one said air distribution fabric layer;
- and
- said air distribution fabric layer being structured and arranged with said perforated film layer to spread air in said air distribution fabric layer a distance greater than said perforate distance.
1 more element
An anti-rewet fabric for carrying a fiber web through an air press, the anti-rewet fabric comprising:
- at least one air distribution fabric layer, one said air distribution fabric layer being configured for contacting the fiber web;
- and
- a perforated film layer, said perforated film layer being comprised of one of a polyester film and a plastic film, said perforated film layer having a first film side and a second film side, said first film side being one of laminated and attached to said one said air distribution fabric layer;
- wherein each said air distribution fabric layer includes a multi-float weave.
1 more element
An anti-rewet fabric for carrying a fiber web through an air press, the anti-rewet fabric comprising:
- at least one air distribution fabric layer, one said air distribution fabric layer being configured for contacting the fiber web;
- and
- a perforated film layer, said perforated film layer being comprised of one of a polyester film and a plastic film, said perforated film layer having a first film side and a second film side, said first film side being one of laminated and attached to said one said air distribution fabric layer;
- wherein said perforated film layer has a series of perforate holes therein, each set of most-closely spaced perforate holes being separated by a perforate distance, each said air distribution fabric layer having a fabric weave associated therewith, said fabric weave having a weave repeat distance, said weave repeat distance being greater than said perforate distance.
1 more element
A method of conveying a fiber web into an air press, said air press having a nip, said method comprising the steps of:
- providing an anti-rewet fabric for carrying the fiber web through said air press, said anti-rewet fabric comprising:
- at least one air distribution fabric layer configured for contacting the fiber web;
- a perforated film layer, said perforated film layer being comprised of one of a polyester film and a plastic film, said perforated film layer defining a plurality of holes therethrough separated from each other by a perforate distance, said perforated film layer having a first film side and a second film side, said first film side being one of laminated and attached to one said air distribution fabric layer;
- and
- said air distribution fabric layer being structured and arranged with said perforated film layer to spread air in said air distribution fabric layer a distance greater than said perforate distance;
- and
- carrying the fiber web on one said air distribution fabric layer of said anti-rewet fabric into said air press through said nip;
- and
- spreading air in said air distribution fabric layer a distance greater than said perforate distance.
6 more elements
A papermaking machine for making a fiber web, said papermaking machine comprising:
- a plurality of conveyor rolls for carrying the fiber web;
- first and second opposing press elements, said first press element and said second press element together forming a nip therebetween;
- at least a first anti-rewet fabric configured for carrying the fiber web through said nip, said first anti-rewet fabric including:
- at least one air distribution fabric layer, one said air distribution fabric layer being configured for contacting the fiber web;
- and
- a perforated film layer, said perforated film layer being comprised of one of a polyester film and a plastic film, said perforated film layer defining a plurality of holes therethrough separated from each other by a perforate distance, said perforated film layer having a first film side and a second film side, said first film side being one of laminated and attached to said one said air distribution fabric layer, said second film side being directed toward one of said first and second opposing press elements, air distribution fabric layer being structured and arranged with said perforated film layer to spread air in said air distribution fabric layer a distance greater than said perforate distance.
3 more elements
A method of dewatering a fiber web, the fiber web initially containing water therein, said method comprising the steps of:
- providing an air press for dewatering the fiber web, said air press having a nip and an air pressure chamber, said air pressure chamber having air under pressure therein;
- providing at least a first fabric and a second fabric for carrying the fiber web through said air press, at least one of said first fabric and said second fabric including:
- at least one air distribution fabric layer configured for contacting the fiber web;
- a perforated film layer, said perforated film layer being comprised of one of a polyester film and a plastic film, said perforated film layer defining a plurality of holes therethrough separated from each other by a perforate distance, said perforated film layer having a first film side and a second film side, said first film side being one of laminated and attached to one said air distribution fabric layer;
- and
- said air distribution fabric layer being structured and arranged with said perforated film layer to spread air in said air distribution fabric layer a distance greater than said perforate distance;
- and
- carrying the fiber web between said first fabric and said second fabric through said nip and into said air pressure chamber of said air press;
- displacing the water initially contained in said fiber web with the air in said air pressure chamber;
- transferring at least some of the displaced water into said at least one of said first fabric and said second fabric;
- and
- spreading air in said air distribution fabric layer a distance greater than said perforate distance.
9 more elements
A method of dewatering a fiber web, the fiber web initially containing water therein, said method comprising the steps of:
- providing an air press for dewatering the fiber web, said air press having a nip and an air pressure chamber, said air pressure chamber having air under pressure therein;
- providing a first fabric and a second fabric for carrying the fiber web through said air press;
- carrying the fiber web between said first fabric and said second fabric through said nip and into said air pressure chamber of said air press;
- and
- displacing the water initially contained in said fiber web with the air in said air pressure chamber;
- wherein at least said first fabric is an anti-rewet fabric, said anti-rewet fabric being configured for promoting only a one-way flow of water therethrough, said one-way flow being directed away from the fiber web;
- and
- wherein at least one of said first fabric and said second fabric has a three-dimensional structure configured for creating an imprint thereof in the fiber web.
5 more elements
A press unit for dewatering a fiber web, said press unit comprising:
- first and second opposing press elements, said first press element and said second press element together forming a nip therebetween, said first press element being an enclosure, and said second press element being a counter element positioned opposite said enclosure;
- at least one anti-rewet fabric configured for carrying the fiber web through said nip, each said anti-rewet fabric having a first fabric side and a second fabric side, each said anti-rewet fabric including:
- at least one air distribution fabric layer, one air distribution fabric layer being configured for contacting the fiber web;
- and
- a perforated film layer, said perforated film layer being comprised of one of a polyester film and a plastic film, said perforated film layer having a first film side and a second film side, said first film side being one of laminated and attached to said one air distribution fabric layer, said second film side being directed toward said counter element;
- and
- wherein said at least one anti-rewet fabric includes a first anti-rewet fabric, said press unit further comprising a second fabric, said first anti-rewet fabric being configured so as to be arranged between the fiber web and said counter element, said second fabric being configured so as to be arranged between the fiber web and said enclosure, said first anti-rewet fabric and said second fabric have a first permeability and a second permeability, respectively, said first permeability being one of equal to and greater than said second permeability.
4 more elements
Dependencies are inferred from the claim text.