Abstract: This invention pertains to papermaking felts, methods of making such felts, methods of using the felts, and methods of making paper using such felts. A felt of the invention contains at least one substrate web having a fuse-bonded joint extending across the width of the felt. The joint is preferably formed by superposing, onto each other, end portions of a flat-woven substrate web element, with the end portions extending away from the ends in a common direction, and concurrently severing the ends from the end portions, and fuse bonding the end portions to each other, along a common cut line.

Abstract: A felt for use in a papermaking machine consists of a textile base fabric and a batt layer for supporting the paper web. A flow control layer is interposed between the base layer and the batt layer, to prevent rewetting of the paper web upon the paper web exiting the press nip of the paper making machine. The flow control layer is formed of a porous hydrophobic material. Pressure exerted by the press nip forces water from the paper through the upper batt layer and the flow control layer into the base layer. When such pressure is relieved, the hydrophobicity of the flow control layer prevents backflow of water to the upper batt layer and the paper web, to prevent rewetting of the web. The flow control layer is preferably formed of a spunbonded filamentary nylon material treated with a hydrophobic chemical composition, which maintains its integrity during the needling process in which the batt layer and the base layer are secured together.

Abstract: An apparatus for measuring air permeability and boundary air flow for a papermaking fabric, such as a dryer felt. The apparatus includes a housing having an open front end bordered by a lower straight edge. An air flow measuring device, such as an anemometer is mounted in the rear surface of the housing a funnel-shaped deflector directs air entering the open front end of the housing to the anemometer. Air flowing through the anemometer generates an electrical signal in proportion to air flow. The electrical signal actuates a visual display mounted on the housing which provides a visual indication of air flow. A thin blade is mounted at the open front edge of the housing and is adapted to ride along the moving fabric when the apparatus is used. A handle is secured to the upper surface of the housing and extends forwardly of the front end and is adapted to be grasped by an operator.

Abstract: A component to be used in a papermaking machine for extracting moistu re from a paper web. The component includes a supporting structure and a water permeable member is mounted on the supporting structure and is adapted to support a paper web. The water permeable member comprises a rigid mass of ceramic foam having a plurality of interconnected cells. The ceramic foam has an air permeability in the range of 10 to 1,000 cubic feet per square foot of surface area per minute and has a density of 5 to 100 lbs/cubic foot. When a pressure differential is applied to the permeable member to the paper web, moisture will be extracted from the web and passes through the permeable member.

Abstract: A gauge for measuring the pressure of a shower or water spray used in a papermaking machine. The gauge includes a body and an arm extends laterally outward from one end of the body and is adapted to be supported on a water conduit or pipe that contains a shower of nozzles. An alignment plate is mounted on the body and has an opening to receive the liquid stream being discharged from the nozzle. A pressure sensing device is located on the opposite side of the alignment plate, and the liquid stream passing through the opening in the alignment plate will strike the pressure sensing device to generate an electrical signal in proportion to the pressure. The electrical signal is then transformed into a measurement of pressure in psi which is displayed on a readout or gauge mounted on the body. The arm can be adjustably connected to the body to thereby adjust the spacing between the nozzle and the pressure sensor, depending upon the diameter of the water conduit.

Abstract: The invention is directed to a method for extracting water from a paper web in a paper making machine using a ceramic foam component. The component includes a supporting structure and a water permeable member is mounted on the supporting structure and is adapted to support a paper web. The water permeable member comprises a rigid mass of ceramic foam having a plurality of interconnected cells. The ceramic foam has an air permeability in the range of 10 to 1,000 cubic feet per square foot of surface area per minute and has a density of 5 to 100 lbs/cubic foot. When a pressure differential is applied to the permeable member to the paper web, moisture will be extracted from the web and passes through the permeable member.

Abstract: A papermaker's felt having improved water extraction characteristics. The felt is composed of a base fabric, and a layer of a closed cell polymeric foam is disposed on a face of the base fabric. A batt of fibrous material is needled to the base fabric and foam layer. The needling operation penetrates the fibers of the batt into the foam layer, intersecting the cells. The resiliency of the foam tends to close the cell walls against the penetrated fibers so that under uncompressed conditions, the felt is substantially impervious. Under compressive forces, as occurs in the nip between press rolls, the interfaces between the penetrated fibers and the cell walls will open to enable water to be extracted through the felt.

Abstract: An instrument for measuring the air flow through a papermaker's felt at a location in registry with a vacuum box. The instrument includes a housing having a generally rectangular discharge outlet which is placed in contact with the felt in registry with the slot of a vacuum box. The housing includes an inlet chamber which houses an anemometer, and as the air is drawn into the inlet chamber by virtue of the vacuum created in the vacuum box, the air flow will rotate the anemometer vanes. A sensor produces an electrical signal in accordance with the speed of rotation of the anemometer and the signal generates, through suitable circuitry, a visual readout of the air flow. The device can be used to measure the permeability of the felt, as well as the air flow through the vacuum box.